1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2015 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
22 #include "coretypes.h"
29 #include "fold-const.h"
30 #include "stor-layout.h"
32 #include "stringpool.h"
34 #include "internal-fn.h"
36 #include "insn-config.h"
44 #include "insn-codes.h"
48 #include "diagnostic-core.h"
52 #include "langhooks.h"
58 #include "tree-chkp.h"
62 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
63 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
65 /* Data structure and subroutines used within expand_call. */
69 /* Tree node for this argument. */
71 /* Mode for value; TYPE_MODE unless promoted. */
73 /* Current RTL value for argument, or 0 if it isn't precomputed. */
75 /* Initially-compute RTL value for argument; only for const functions. */
77 /* Register to pass this argument in, 0 if passed on stack, or an
78 PARALLEL if the arg is to be copied into multiple non-contiguous
81 /* Register to pass this argument in when generating tail call sequence.
82 This is not the same register as for normal calls on machines with
85 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
86 form for emit_group_move. */
88 /* If value is passed in neither reg nor stack, this field holds a number
89 of a special slot to be used. */
91 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
92 there is no such pointer. */
94 /* If pointer_arg refers a structure, then pointer_offset holds an offset
95 of a pointer in this structure. */
97 /* If REG was promoted from the actual mode of the argument expression,
98 indicates whether the promotion is sign- or zero-extended. */
100 /* Number of bytes to put in registers. 0 means put the whole arg
101 in registers. Also 0 if not passed in registers. */
103 /* Nonzero if argument must be passed on stack.
104 Note that some arguments may be passed on the stack
105 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
106 pass_on_stack identifies arguments that *cannot* go in registers. */
108 /* Some fields packaged up for locate_and_pad_parm. */
109 struct locate_and_pad_arg_data locate;
110 /* Location on the stack at which parameter should be stored. The store
111 has already been done if STACK == VALUE. */
113 /* Location on the stack of the start of this argument slot. This can
114 differ from STACK if this arg pads downward. This location is known
115 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
117 /* Place that this stack area has been saved, if needed. */
119 /* If an argument's alignment does not permit direct copying into registers,
120 copy in smaller-sized pieces into pseudos. These are stored in a
121 block pointed to by this field. The next field says how many
122 word-sized pseudos we made. */
127 /* A vector of one char per byte of stack space. A byte if nonzero if
128 the corresponding stack location has been used.
129 This vector is used to prevent a function call within an argument from
130 clobbering any stack already set up. */
131 static char *stack_usage_map;
133 /* Size of STACK_USAGE_MAP. */
134 static int highest_outgoing_arg_in_use;
136 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
137 stack location's tail call argument has been already stored into the stack.
138 This bitmap is used to prevent sibling call optimization if function tries
139 to use parent's incoming argument slots when they have been already
140 overwritten with tail call arguments. */
141 static sbitmap stored_args_map;
143 /* stack_arg_under_construction is nonzero when an argument may be
144 initialized with a constructor call (including a C function that
145 returns a BLKmode struct) and expand_call must take special action
146 to make sure the object being constructed does not overlap the
147 argument list for the constructor call. */
148 static int stack_arg_under_construction;
150 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
151 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
153 static void precompute_register_parameters (int, struct arg_data *, int *);
154 static void store_bounds (struct arg_data *, struct arg_data *);
155 static int store_one_arg (struct arg_data *, rtx, int, int, int);
156 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
157 static int finalize_must_preallocate (int, int, struct arg_data *,
159 static void precompute_arguments (int, struct arg_data *);
160 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
161 static void initialize_argument_information (int, struct arg_data *,
162 struct args_size *, int,
164 tree, tree, cumulative_args_t, int,
165 rtx *, int *, int *, int *,
167 static void compute_argument_addresses (struct arg_data *, rtx, int);
168 static rtx rtx_for_function_call (tree, tree);
169 static void load_register_parameters (struct arg_data *, int, rtx *, int,
171 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
172 machine_mode, int, va_list);
173 static int special_function_p (const_tree, int);
174 static int check_sibcall_argument_overlap_1 (rtx);
175 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
177 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
179 static tree split_complex_types (tree);
181 #ifdef REG_PARM_STACK_SPACE
182 static rtx save_fixed_argument_area (int, rtx, int *, int *);
183 static void restore_fixed_argument_area (rtx, rtx, int, int);
186 /* Force FUNEXP into a form suitable for the address of a CALL,
187 and return that as an rtx. Also load the static chain register
188 if FNDECL is a nested function.
190 CALL_FUSAGE points to a variable holding the prospective
191 CALL_INSN_FUNCTION_USAGE information. */
194 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
195 rtx *call_fusage, int reg_parm_seen, int sibcallp)
197 /* Make a valid memory address and copy constants through pseudo-regs,
198 but not for a constant address if -fno-function-cse. */
199 if (GET_CODE (funexp) != SYMBOL_REF)
200 /* If we are using registers for parameters, force the
201 function address into a register now. */
202 funexp = ((reg_parm_seen
203 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
204 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
205 : memory_address (FUNCTION_MODE, funexp));
208 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
209 funexp = force_reg (Pmode, funexp);
212 if (static_chain_value != 0
213 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
214 || DECL_STATIC_CHAIN (fndecl_or_type)))
218 chain = targetm.calls.static_chain (fndecl_or_type, false);
219 static_chain_value = convert_memory_address (Pmode, static_chain_value);
221 emit_move_insn (chain, static_chain_value);
223 use_reg (call_fusage, chain);
229 /* Generate instructions to call function FUNEXP,
230 and optionally pop the results.
231 The CALL_INSN is the first insn generated.
233 FNDECL is the declaration node of the function. This is given to the
234 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
237 FUNTYPE is the data type of the function. This is given to the hook
238 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
239 own args. We used to allow an identifier for library functions, but
240 that doesn't work when the return type is an aggregate type and the
241 calling convention says that the pointer to this aggregate is to be
242 popped by the callee.
244 STACK_SIZE is the number of bytes of arguments on the stack,
245 ROUNDED_STACK_SIZE is that number rounded up to
246 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
247 both to put into the call insn and to generate explicit popping
250 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
251 It is zero if this call doesn't want a structure value.
253 NEXT_ARG_REG is the rtx that results from executing
254 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
255 just after all the args have had their registers assigned.
256 This could be whatever you like, but normally it is the first
257 arg-register beyond those used for args in this call,
258 or 0 if all the arg-registers are used in this call.
259 It is passed on to `gen_call' so you can put this info in the call insn.
261 VALREG is a hard register in which a value is returned,
262 or 0 if the call does not return a value.
264 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
265 the args to this call were processed.
266 We restore `inhibit_defer_pop' to that value.
268 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
269 denote registers used by the called function. */
272 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
273 tree funtype ATTRIBUTE_UNUSED,
274 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
275 HOST_WIDE_INT rounded_stack_size,
276 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
277 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
278 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
279 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
281 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
282 rtx call, funmem, pat;
283 int already_popped = 0;
284 HOST_WIDE_INT n_popped
285 = targetm.calls.return_pops_args (fndecl, funtype, stack_size);
287 #ifdef CALL_POPS_ARGS
288 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
291 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
292 and we don't want to load it into a register as an optimization,
293 because prepare_call_address already did it if it should be done. */
294 if (GET_CODE (funexp) != SYMBOL_REF)
295 funexp = memory_address (FUNCTION_MODE, funexp);
297 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
298 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
302 /* Although a built-in FUNCTION_DECL and its non-__builtin
303 counterpart compare equal and get a shared mem_attrs, they
304 produce different dump output in compare-debug compilations,
305 if an entry gets garbage collected in one compilation, then
306 adds a different (but equivalent) entry, while the other
307 doesn't run the garbage collector at the same spot and then
308 shares the mem_attr with the equivalent entry. */
309 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
311 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
316 set_mem_expr (funmem, t);
319 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
321 if (ecf_flags & ECF_SIBCALL)
324 pat = targetm.gen_sibcall_value (valreg, funmem,
325 rounded_stack_size_rtx,
326 next_arg_reg, NULL_RTX);
328 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
329 next_arg_reg, GEN_INT (struct_value_size));
331 /* If the target has "call" or "call_value" insns, then prefer them
332 if no arguments are actually popped. If the target does not have
333 "call" or "call_value" insns, then we must use the popping versions
334 even if the call has no arguments to pop. */
335 else if (n_popped > 0
337 ? targetm.have_call_value ()
338 : targetm.have_call ()))
340 rtx n_pop = GEN_INT (n_popped);
342 /* If this subroutine pops its own args, record that in the call insn
343 if possible, for the sake of frame pointer elimination. */
346 pat = targetm.gen_call_value_pop (valreg, funmem,
347 rounded_stack_size_rtx,
348 next_arg_reg, n_pop);
350 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
351 next_arg_reg, n_pop);
358 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
359 next_arg_reg, NULL_RTX);
361 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
362 GEN_INT (struct_value_size));
366 /* Find the call we just emitted. */
367 rtx_call_insn *call_insn = last_call_insn ();
369 /* Some target create a fresh MEM instead of reusing the one provided
370 above. Set its MEM_EXPR. */
371 call = get_call_rtx_from (call_insn);
373 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
374 && MEM_EXPR (funmem) != NULL_TREE)
375 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
377 /* Mark instrumented calls. */
379 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
381 /* Put the register usage information there. */
382 add_function_usage_to (call_insn, call_fusage);
384 /* If this is a const call, then set the insn's unchanging bit. */
385 if (ecf_flags & ECF_CONST)
386 RTL_CONST_CALL_P (call_insn) = 1;
388 /* If this is a pure call, then set the insn's unchanging bit. */
389 if (ecf_flags & ECF_PURE)
390 RTL_PURE_CALL_P (call_insn) = 1;
392 /* If this is a const call, then set the insn's unchanging bit. */
393 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
394 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
396 /* Create a nothrow REG_EH_REGION note, if needed. */
397 make_reg_eh_region_note (call_insn, ecf_flags, 0);
399 if (ecf_flags & ECF_NORETURN)
400 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
402 if (ecf_flags & ECF_RETURNS_TWICE)
404 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
405 cfun->calls_setjmp = 1;
408 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
410 /* Restore this now, so that we do defer pops for this call's args
411 if the context of the call as a whole permits. */
412 inhibit_defer_pop = old_inhibit_defer_pop;
417 CALL_INSN_FUNCTION_USAGE (call_insn)
418 = gen_rtx_EXPR_LIST (VOIDmode,
419 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
420 CALL_INSN_FUNCTION_USAGE (call_insn));
421 rounded_stack_size -= n_popped;
422 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
423 stack_pointer_delta -= n_popped;
425 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
427 /* If popup is needed, stack realign must use DRAP */
428 if (SUPPORTS_STACK_ALIGNMENT)
429 crtl->need_drap = true;
431 /* For noreturn calls when not accumulating outgoing args force
432 REG_ARGS_SIZE note to prevent crossjumping of calls with different
434 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
435 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
437 if (!ACCUMULATE_OUTGOING_ARGS)
439 /* If returning from the subroutine does not automatically pop the args,
440 we need an instruction to pop them sooner or later.
441 Perhaps do it now; perhaps just record how much space to pop later.
443 If returning from the subroutine does pop the args, indicate that the
444 stack pointer will be changed. */
446 if (rounded_stack_size != 0)
448 if (ecf_flags & ECF_NORETURN)
449 /* Just pretend we did the pop. */
450 stack_pointer_delta -= rounded_stack_size;
451 else if (flag_defer_pop && inhibit_defer_pop == 0
452 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
453 pending_stack_adjust += rounded_stack_size;
455 adjust_stack (rounded_stack_size_rtx);
458 /* When we accumulate outgoing args, we must avoid any stack manipulations.
459 Restore the stack pointer to its original value now. Usually
460 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
461 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
462 popping variants of functions exist as well.
464 ??? We may optimize similar to defer_pop above, but it is
465 probably not worthwhile.
467 ??? It will be worthwhile to enable combine_stack_adjustments even for
470 anti_adjust_stack (GEN_INT (n_popped));
473 /* Determine if the function identified by NAME and FNDECL is one with
474 special properties we wish to know about.
476 For example, if the function might return more than one time (setjmp), then
477 set RETURNS_TWICE to a nonzero value.
479 Similarly set NORETURN if the function is in the longjmp family.
481 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
482 space from the stack such as alloca. */
485 special_function_p (const_tree fndecl, int flags)
487 tree name_decl = DECL_NAME (fndecl);
489 /* For instrumentation clones we want to derive flags
490 from the original name. */
491 if (cgraph_node::get (fndecl)
492 && cgraph_node::get (fndecl)->instrumentation_clone)
493 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
495 if (fndecl && name_decl
496 && IDENTIFIER_LENGTH (name_decl) <= 17
497 /* Exclude functions not at the file scope, or not `extern',
498 since they are not the magic functions we would otherwise
500 FIXME: this should be handled with attributes, not with this
501 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
502 because you can declare fork() inside a function if you
504 && (DECL_CONTEXT (fndecl) == NULL_TREE
505 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
506 && TREE_PUBLIC (fndecl))
508 const char *name = IDENTIFIER_POINTER (name_decl);
509 const char *tname = name;
511 /* We assume that alloca will always be called by name. It
512 makes no sense to pass it as a pointer-to-function to
513 anything that does not understand its behavior. */
514 if (((IDENTIFIER_LENGTH (name_decl) == 6
516 && ! strcmp (name, "alloca"))
517 || (IDENTIFIER_LENGTH (name_decl) == 16
519 && ! strcmp (name, "__builtin_alloca"))))
520 flags |= ECF_MAY_BE_ALLOCA;
522 /* Disregard prefix _, __, __x or __builtin_. */
527 && !strncmp (name + 3, "uiltin_", 7))
529 else if (name[1] == '_' && name[2] == 'x')
531 else if (name[1] == '_')
540 && (! strcmp (tname, "setjmp")
541 || ! strcmp (tname, "setjmp_syscall")))
543 && ! strcmp (tname, "sigsetjmp"))
545 && ! strcmp (tname, "savectx")))
546 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
549 && ! strcmp (tname, "siglongjmp"))
550 flags |= ECF_NORETURN;
552 else if ((tname[0] == 'q' && tname[1] == 's'
553 && ! strcmp (tname, "qsetjmp"))
554 || (tname[0] == 'v' && tname[1] == 'f'
555 && ! strcmp (tname, "vfork"))
556 || (tname[0] == 'g' && tname[1] == 'e'
557 && !strcmp (tname, "getcontext")))
558 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
560 else if (tname[0] == 'l' && tname[1] == 'o'
561 && ! strcmp (tname, "longjmp"))
562 flags |= ECF_NORETURN;
568 /* Similar to special_function_p; return a set of ERF_ flags for the
571 decl_return_flags (tree fndecl)
574 tree type = TREE_TYPE (fndecl);
578 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
582 attr = TREE_VALUE (TREE_VALUE (attr));
583 if (!attr || TREE_STRING_LENGTH (attr) < 1)
586 switch (TREE_STRING_POINTER (attr)[0])
592 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
603 /* Return nonzero when FNDECL represents a call to setjmp. */
606 setjmp_call_p (const_tree fndecl)
608 if (DECL_IS_RETURNS_TWICE (fndecl))
609 return ECF_RETURNS_TWICE;
610 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
614 /* Return true if STMT is an alloca call. */
617 gimple_alloca_call_p (const gimple *stmt)
621 if (!is_gimple_call (stmt))
624 fndecl = gimple_call_fndecl (stmt);
625 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
631 /* Return true when exp contains alloca call. */
634 alloca_call_p (const_tree exp)
637 if (TREE_CODE (exp) == CALL_EXPR
638 && (fndecl = get_callee_fndecl (exp))
639 && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
644 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
645 function. Return FALSE otherwise. */
648 is_tm_builtin (const_tree fndecl)
653 if (decl_is_tm_clone (fndecl))
656 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
658 switch (DECL_FUNCTION_CODE (fndecl))
660 case BUILT_IN_TM_COMMIT:
661 case BUILT_IN_TM_COMMIT_EH:
662 case BUILT_IN_TM_ABORT:
663 case BUILT_IN_TM_IRREVOCABLE:
664 case BUILT_IN_TM_GETTMCLONE_IRR:
665 case BUILT_IN_TM_MEMCPY:
666 case BUILT_IN_TM_MEMMOVE:
667 case BUILT_IN_TM_MEMSET:
668 CASE_BUILT_IN_TM_STORE (1):
669 CASE_BUILT_IN_TM_STORE (2):
670 CASE_BUILT_IN_TM_STORE (4):
671 CASE_BUILT_IN_TM_STORE (8):
672 CASE_BUILT_IN_TM_STORE (FLOAT):
673 CASE_BUILT_IN_TM_STORE (DOUBLE):
674 CASE_BUILT_IN_TM_STORE (LDOUBLE):
675 CASE_BUILT_IN_TM_STORE (M64):
676 CASE_BUILT_IN_TM_STORE (M128):
677 CASE_BUILT_IN_TM_STORE (M256):
678 CASE_BUILT_IN_TM_LOAD (1):
679 CASE_BUILT_IN_TM_LOAD (2):
680 CASE_BUILT_IN_TM_LOAD (4):
681 CASE_BUILT_IN_TM_LOAD (8):
682 CASE_BUILT_IN_TM_LOAD (FLOAT):
683 CASE_BUILT_IN_TM_LOAD (DOUBLE):
684 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
685 CASE_BUILT_IN_TM_LOAD (M64):
686 CASE_BUILT_IN_TM_LOAD (M128):
687 CASE_BUILT_IN_TM_LOAD (M256):
688 case BUILT_IN_TM_LOG:
689 case BUILT_IN_TM_LOG_1:
690 case BUILT_IN_TM_LOG_2:
691 case BUILT_IN_TM_LOG_4:
692 case BUILT_IN_TM_LOG_8:
693 case BUILT_IN_TM_LOG_FLOAT:
694 case BUILT_IN_TM_LOG_DOUBLE:
695 case BUILT_IN_TM_LOG_LDOUBLE:
696 case BUILT_IN_TM_LOG_M64:
697 case BUILT_IN_TM_LOG_M128:
698 case BUILT_IN_TM_LOG_M256:
707 /* Detect flags (function attributes) from the function decl or type node. */
710 flags_from_decl_or_type (const_tree exp)
716 /* The function exp may have the `malloc' attribute. */
717 if (DECL_IS_MALLOC (exp))
720 /* The function exp may have the `returns_twice' attribute. */
721 if (DECL_IS_RETURNS_TWICE (exp))
722 flags |= ECF_RETURNS_TWICE;
724 /* Process the pure and const attributes. */
725 if (TREE_READONLY (exp))
727 if (DECL_PURE_P (exp))
729 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
730 flags |= ECF_LOOPING_CONST_OR_PURE;
732 if (DECL_IS_NOVOPS (exp))
734 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
737 if (TREE_NOTHROW (exp))
738 flags |= ECF_NOTHROW;
742 if (is_tm_builtin (exp))
743 flags |= ECF_TM_BUILTIN;
744 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
745 || lookup_attribute ("transaction_pure",
746 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
747 flags |= ECF_TM_PURE;
750 flags = special_function_p (exp, flags);
752 else if (TYPE_P (exp))
754 if (TYPE_READONLY (exp))
758 && ((flags & ECF_CONST) != 0
759 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
760 flags |= ECF_TM_PURE;
765 if (TREE_THIS_VOLATILE (exp))
767 flags |= ECF_NORETURN;
768 if (flags & (ECF_CONST|ECF_PURE))
769 flags |= ECF_LOOPING_CONST_OR_PURE;
775 /* Detect flags from a CALL_EXPR. */
778 call_expr_flags (const_tree t)
781 tree decl = get_callee_fndecl (t);
784 flags = flags_from_decl_or_type (decl);
785 else if (CALL_EXPR_FN (t) == NULL_TREE)
786 flags = internal_fn_flags (CALL_EXPR_IFN (t));
789 t = TREE_TYPE (CALL_EXPR_FN (t));
790 if (t && TREE_CODE (t) == POINTER_TYPE)
791 flags = flags_from_decl_or_type (TREE_TYPE (t));
799 /* Return true if TYPE should be passed by invisible reference. */
802 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
803 tree type, bool named_arg)
807 /* If this type contains non-trivial constructors, then it is
808 forbidden for the middle-end to create any new copies. */
809 if (TREE_ADDRESSABLE (type))
812 /* GCC post 3.4 passes *all* variable sized types by reference. */
813 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
816 /* If a record type should be passed the same as its first (and only)
817 member, use the type and mode of that member. */
818 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
820 type = TREE_TYPE (first_field (type));
821 mode = TYPE_MODE (type);
825 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
829 /* Return true if TYPE, which is passed by reference, should be callee
830 copied instead of caller copied. */
833 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
834 tree type, bool named_arg)
836 if (type && TREE_ADDRESSABLE (type))
838 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
843 /* Precompute all register parameters as described by ARGS, storing values
844 into fields within the ARGS array.
846 NUM_ACTUALS indicates the total number elements in the ARGS array.
848 Set REG_PARM_SEEN if we encounter a register parameter. */
851 precompute_register_parameters (int num_actuals, struct arg_data *args,
858 for (i = 0; i < num_actuals; i++)
859 if (args[i].reg != 0 && ! args[i].pass_on_stack)
863 if (args[i].value == 0)
866 args[i].value = expand_normal (args[i].tree_value);
867 preserve_temp_slots (args[i].value);
871 /* If we are to promote the function arg to a wider mode,
874 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
876 = convert_modes (args[i].mode,
877 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
878 args[i].value, args[i].unsignedp);
880 /* If the value is a non-legitimate constant, force it into a
881 pseudo now. TLS symbols sometimes need a call to resolve. */
882 if (CONSTANT_P (args[i].value)
883 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
884 args[i].value = force_reg (args[i].mode, args[i].value);
886 /* If we're going to have to load the value by parts, pull the
887 parts into pseudos. The part extraction process can involve
888 non-trivial computation. */
889 if (GET_CODE (args[i].reg) == PARALLEL)
891 tree type = TREE_TYPE (args[i].tree_value);
892 args[i].parallel_value
893 = emit_group_load_into_temps (args[i].reg, args[i].value,
894 type, int_size_in_bytes (type));
897 /* If the value is expensive, and we are inside an appropriately
898 short loop, put the value into a pseudo and then put the pseudo
901 For small register classes, also do this if this call uses
902 register parameters. This is to avoid reload conflicts while
903 loading the parameters registers. */
905 else if ((! (REG_P (args[i].value)
906 || (GET_CODE (args[i].value) == SUBREG
907 && REG_P (SUBREG_REG (args[i].value)))))
908 && args[i].mode != BLKmode
909 && (set_src_cost (args[i].value, args[i].mode,
910 optimize_insn_for_speed_p ())
913 && targetm.small_register_classes_for_mode_p (args[i].mode))
915 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
919 #ifdef REG_PARM_STACK_SPACE
921 /* The argument list is the property of the called routine and it
922 may clobber it. If the fixed area has been used for previous
923 parameters, we must save and restore it. */
926 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
931 /* Compute the boundary of the area that needs to be saved, if any. */
932 high = reg_parm_stack_space;
933 if (ARGS_GROW_DOWNWARD)
936 if (high > highest_outgoing_arg_in_use)
937 high = highest_outgoing_arg_in_use;
939 for (low = 0; low < high; low++)
940 if (stack_usage_map[low] != 0)
943 machine_mode save_mode;
949 while (stack_usage_map[--high] == 0)
953 *high_to_save = high;
955 num_to_save = high - low + 1;
956 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
958 /* If we don't have the required alignment, must do this
960 if ((low & (MIN (GET_MODE_SIZE (save_mode),
961 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
964 if (ARGS_GROW_DOWNWARD)
969 addr = plus_constant (Pmode, argblock, delta);
970 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
972 set_mem_align (stack_area, PARM_BOUNDARY);
973 if (save_mode == BLKmode)
975 save_area = assign_stack_temp (BLKmode, num_to_save);
976 emit_block_move (validize_mem (save_area), stack_area,
977 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
981 save_area = gen_reg_rtx (save_mode);
982 emit_move_insn (save_area, stack_area);
992 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
994 machine_mode save_mode = GET_MODE (save_area);
996 rtx addr, stack_area;
998 if (ARGS_GROW_DOWNWARD)
999 delta = -high_to_save;
1001 delta = low_to_save;
1003 addr = plus_constant (Pmode, argblock, delta);
1004 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1005 set_mem_align (stack_area, PARM_BOUNDARY);
1007 if (save_mode != BLKmode)
1008 emit_move_insn (stack_area, save_area);
1010 emit_block_move (stack_area, validize_mem (save_area),
1011 GEN_INT (high_to_save - low_to_save + 1),
1012 BLOCK_OP_CALL_PARM);
1014 #endif /* REG_PARM_STACK_SPACE */
1016 /* If any elements in ARGS refer to parameters that are to be passed in
1017 registers, but not in memory, and whose alignment does not permit a
1018 direct copy into registers. Copy the values into a group of pseudos
1019 which we will later copy into the appropriate hard registers.
1021 Pseudos for each unaligned argument will be stored into the array
1022 args[argnum].aligned_regs. The caller is responsible for deallocating
1023 the aligned_regs array if it is nonzero. */
1026 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1030 for (i = 0; i < num_actuals; i++)
1031 if (args[i].reg != 0 && ! args[i].pass_on_stack
1032 && GET_CODE (args[i].reg) != PARALLEL
1033 && args[i].mode == BLKmode
1034 && MEM_P (args[i].value)
1035 && (MEM_ALIGN (args[i].value)
1036 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1038 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1039 int endian_correction = 0;
1041 if (args[i].partial)
1043 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1044 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1048 args[i].n_aligned_regs
1049 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1052 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1054 /* Structures smaller than a word are normally aligned to the
1055 least significant byte. On a BYTES_BIG_ENDIAN machine,
1056 this means we must skip the empty high order bytes when
1057 calculating the bit offset. */
1058 if (bytes < UNITS_PER_WORD
1059 #ifdef BLOCK_REG_PADDING
1060 && (BLOCK_REG_PADDING (args[i].mode,
1061 TREE_TYPE (args[i].tree_value), 1)
1067 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1069 for (j = 0; j < args[i].n_aligned_regs; j++)
1071 rtx reg = gen_reg_rtx (word_mode);
1072 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1073 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1075 args[i].aligned_regs[j] = reg;
1076 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1077 word_mode, word_mode);
1079 /* There is no need to restrict this code to loading items
1080 in TYPE_ALIGN sized hunks. The bitfield instructions can
1081 load up entire word sized registers efficiently.
1083 ??? This may not be needed anymore.
1084 We use to emit a clobber here but that doesn't let later
1085 passes optimize the instructions we emit. By storing 0 into
1086 the register later passes know the first AND to zero out the
1087 bitfield being set in the register is unnecessary. The store
1088 of 0 will be deleted as will at least the first AND. */
1090 emit_move_insn (reg, const0_rtx);
1092 bytes -= bitsize / BITS_PER_UNIT;
1093 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1099 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1102 NUM_ACTUALS is the total number of parameters.
1104 N_NAMED_ARGS is the total number of named arguments.
1106 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1109 FNDECL is the tree code for the target of this call (if known)
1111 ARGS_SO_FAR holds state needed by the target to know where to place
1114 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1115 for arguments which are passed in registers.
1117 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1118 and may be modified by this routine.
1120 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1121 flags which may be modified by this routine.
1123 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1124 that requires allocation of stack space.
1126 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1127 the thunked-to function. */
1130 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1131 struct arg_data *args,
1132 struct args_size *args_size,
1133 int n_named_args ATTRIBUTE_UNUSED,
1134 tree exp, tree struct_value_addr_value,
1135 tree fndecl, tree fntype,
1136 cumulative_args_t args_so_far,
1137 int reg_parm_stack_space,
1138 rtx *old_stack_level, int *old_pending_adj,
1139 int *must_preallocate, int *ecf_flags,
1140 bool *may_tailcall, bool call_from_thunk_p)
1142 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1143 location_t loc = EXPR_LOCATION (exp);
1145 /* Count arg position in order args appear. */
1150 args_size->constant = 0;
1153 bitmap_obstack_initialize (NULL);
1155 /* In this loop, we consider args in the order they are written.
1156 We fill up ARGS from the back. */
1158 i = num_actuals - 1;
1160 int j = i, ptr_arg = -1;
1161 call_expr_arg_iterator iter;
1163 bitmap slots = NULL;
1165 if (struct_value_addr_value)
1167 args[j].tree_value = struct_value_addr_value;
1170 /* If we pass structure address then we need to
1171 create bounds for it. Since created bounds is
1172 a call statement, we expand it right here to avoid
1173 fixing all other places where it may be expanded. */
1174 if (CALL_WITH_BOUNDS_P (exp))
1176 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1178 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1179 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1180 EXPAND_NORMAL, 0, false);
1181 args[j].pointer_arg = j + 1;
1185 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1187 tree argtype = TREE_TYPE (arg);
1189 /* Remember last param with pointer and associate it
1190 with following pointer bounds. */
1191 if (CALL_WITH_BOUNDS_P (exp)
1192 && chkp_type_has_pointer (argtype))
1195 BITMAP_FREE (slots);
1197 if (!BOUNDED_TYPE_P (argtype))
1199 slots = BITMAP_ALLOC (NULL);
1200 chkp_find_bound_slots (argtype, slots);
1203 else if (POINTER_BOUNDS_TYPE_P (argtype))
1205 /* We expect bounds in instrumented calls only.
1206 Otherwise it is a sign we lost flag due to some optimization
1207 and may emit call args incorrectly. */
1208 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1210 /* For structures look for the next available pointer. */
1211 if (ptr_arg != -1 && slots)
1213 unsigned bnd_no = bitmap_first_set_bit (slots);
1214 args[j].pointer_offset =
1215 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1217 bitmap_clear_bit (slots, bnd_no);
1219 /* Check we have no more pointers in the structure. */
1220 if (bitmap_empty_p (slots))
1221 BITMAP_FREE (slots);
1223 args[j].pointer_arg = ptr_arg;
1225 /* Check we covered all pointers in the previous
1233 if (targetm.calls.split_complex_arg
1235 && TREE_CODE (argtype) == COMPLEX_TYPE
1236 && targetm.calls.split_complex_arg (argtype))
1238 tree subtype = TREE_TYPE (argtype);
1239 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1241 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1244 args[j].tree_value = arg;
1249 BITMAP_FREE (slots);
1252 bitmap_obstack_release (NULL);
1254 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1255 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1257 tree type = TREE_TYPE (args[i].tree_value);
1261 /* Replace erroneous argument with constant zero. */
1262 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1263 args[i].tree_value = integer_zero_node, type = integer_type_node;
1265 /* If TYPE is a transparent union or record, pass things the way
1266 we would pass the first field of the union or record. We have
1267 already verified that the modes are the same. */
1268 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1269 && TYPE_TRANSPARENT_AGGR (type))
1270 type = TREE_TYPE (first_field (type));
1272 /* Decide where to pass this arg.
1274 args[i].reg is nonzero if all or part is passed in registers.
1276 args[i].partial is nonzero if part but not all is passed in registers,
1277 and the exact value says how many bytes are passed in registers.
1279 args[i].pass_on_stack is nonzero if the argument must at least be
1280 computed on the stack. It may then be loaded back into registers
1281 if args[i].reg is nonzero.
1283 These decisions are driven by the FUNCTION_... macros and must agree
1284 with those made by function.c. */
1286 /* See if this argument should be passed by invisible reference. */
1287 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1288 type, argpos < n_named_args))
1291 tree base = NULL_TREE;
1294 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1295 type, argpos < n_named_args);
1297 /* If we're compiling a thunk, pass through invisible references
1298 instead of making a copy. */
1299 if (call_from_thunk_p
1301 && !TREE_ADDRESSABLE (type)
1302 && (base = get_base_address (args[i].tree_value))
1303 && TREE_CODE (base) != SSA_NAME
1304 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1306 /* We may have turned the parameter value into an SSA name.
1307 Go back to the original parameter so we can take the
1309 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1311 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1312 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1313 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1315 /* Argument setup code may have copied the value to register. We
1316 revert that optimization now because the tail call code must
1317 use the original location. */
1318 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1319 && !MEM_P (DECL_RTL (args[i].tree_value))
1320 && DECL_INCOMING_RTL (args[i].tree_value)
1321 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1322 set_decl_rtl (args[i].tree_value,
1323 DECL_INCOMING_RTL (args[i].tree_value));
1325 mark_addressable (args[i].tree_value);
1327 /* We can't use sibcalls if a callee-copied argument is
1328 stored in the current function's frame. */
1329 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1330 *may_tailcall = false;
1332 args[i].tree_value = build_fold_addr_expr_loc (loc,
1333 args[i].tree_value);
1334 type = TREE_TYPE (args[i].tree_value);
1336 if (*ecf_flags & ECF_CONST)
1337 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1341 /* We make a copy of the object and pass the address to the
1342 function being called. */
1345 if (!COMPLETE_TYPE_P (type)
1346 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1347 || (flag_stack_check == GENERIC_STACK_CHECK
1348 && compare_tree_int (TYPE_SIZE_UNIT (type),
1349 STACK_CHECK_MAX_VAR_SIZE) > 0))
1351 /* This is a variable-sized object. Make space on the stack
1353 rtx size_rtx = expr_size (args[i].tree_value);
1355 if (*old_stack_level == 0)
1357 emit_stack_save (SAVE_BLOCK, old_stack_level);
1358 *old_pending_adj = pending_stack_adjust;
1359 pending_stack_adjust = 0;
1362 /* We can pass TRUE as the 4th argument because we just
1363 saved the stack pointer and will restore it right after
1365 copy = allocate_dynamic_stack_space (size_rtx,
1369 copy = gen_rtx_MEM (BLKmode, copy);
1370 set_mem_attributes (copy, type, 1);
1373 copy = assign_temp (type, 1, 0);
1375 store_expr (args[i].tree_value, copy, 0, false);
1377 /* Just change the const function to pure and then let
1378 the next test clear the pure based on
1380 if (*ecf_flags & ECF_CONST)
1382 *ecf_flags &= ~ECF_CONST;
1383 *ecf_flags |= ECF_PURE;
1386 if (!callee_copies && *ecf_flags & ECF_PURE)
1387 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1390 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1391 type = TREE_TYPE (args[i].tree_value);
1392 *may_tailcall = false;
1396 unsignedp = TYPE_UNSIGNED (type);
1397 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1398 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1400 args[i].unsignedp = unsignedp;
1401 args[i].mode = mode;
1403 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1404 argpos < n_named_args);
1406 if (args[i].reg && CONST_INT_P (args[i].reg))
1408 args[i].special_slot = args[i].reg;
1412 /* If this is a sibling call and the machine has register windows, the
1413 register window has to be unwinded before calling the routine, so
1414 arguments have to go into the incoming registers. */
1415 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1416 args[i].tail_call_reg
1417 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1418 argpos < n_named_args);
1420 args[i].tail_call_reg = args[i].reg;
1424 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1425 argpos < n_named_args);
1427 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1429 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1430 it means that we are to pass this arg in the register(s) designated
1431 by the PARALLEL, but also to pass it in the stack. */
1432 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1433 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1434 args[i].pass_on_stack = 1;
1436 /* If this is an addressable type, we must preallocate the stack
1437 since we must evaluate the object into its final location.
1439 If this is to be passed in both registers and the stack, it is simpler
1441 if (TREE_ADDRESSABLE (type)
1442 || (args[i].pass_on_stack && args[i].reg != 0))
1443 *must_preallocate = 1;
1445 /* No stack allocation and padding for bounds. */
1446 if (POINTER_BOUNDS_P (args[i].tree_value))
1448 /* Compute the stack-size of this argument. */
1449 else if (args[i].reg == 0 || args[i].partial != 0
1450 || reg_parm_stack_space > 0
1451 || args[i].pass_on_stack)
1452 locate_and_pad_parm (mode, type,
1453 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1458 reg_parm_stack_space,
1459 args[i].pass_on_stack ? 0 : args[i].partial,
1460 fndecl, args_size, &args[i].locate);
1461 #ifdef BLOCK_REG_PADDING
1463 /* The argument is passed entirely in registers. See at which
1464 end it should be padded. */
1465 args[i].locate.where_pad =
1466 BLOCK_REG_PADDING (mode, type,
1467 int_size_in_bytes (type) <= UNITS_PER_WORD);
1470 /* Update ARGS_SIZE, the total stack space for args so far. */
1472 args_size->constant += args[i].locate.size.constant;
1473 if (args[i].locate.size.var)
1474 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1476 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1477 have been used, etc. */
1479 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1480 type, argpos < n_named_args);
1484 /* Update ARGS_SIZE to contain the total size for the argument block.
1485 Return the original constant component of the argument block's size.
1487 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1488 for arguments passed in registers. */
1491 compute_argument_block_size (int reg_parm_stack_space,
1492 struct args_size *args_size,
1493 tree fndecl ATTRIBUTE_UNUSED,
1494 tree fntype ATTRIBUTE_UNUSED,
1495 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1497 int unadjusted_args_size = args_size->constant;
1499 /* For accumulate outgoing args mode we don't need to align, since the frame
1500 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1501 backends from generating misaligned frame sizes. */
1502 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1503 preferred_stack_boundary = STACK_BOUNDARY;
1505 /* Compute the actual size of the argument block required. The variable
1506 and constant sizes must be combined, the size may have to be rounded,
1507 and there may be a minimum required size. */
1511 args_size->var = ARGS_SIZE_TREE (*args_size);
1512 args_size->constant = 0;
1514 preferred_stack_boundary /= BITS_PER_UNIT;
1515 if (preferred_stack_boundary > 1)
1517 /* We don't handle this case yet. To handle it correctly we have
1518 to add the delta, round and subtract the delta.
1519 Currently no machine description requires this support. */
1520 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1521 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1524 if (reg_parm_stack_space > 0)
1527 = size_binop (MAX_EXPR, args_size->var,
1528 ssize_int (reg_parm_stack_space));
1530 /* The area corresponding to register parameters is not to count in
1531 the size of the block we need. So make the adjustment. */
1532 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1534 = size_binop (MINUS_EXPR, args_size->var,
1535 ssize_int (reg_parm_stack_space));
1540 preferred_stack_boundary /= BITS_PER_UNIT;
1541 if (preferred_stack_boundary < 1)
1542 preferred_stack_boundary = 1;
1543 args_size->constant = (((args_size->constant
1544 + stack_pointer_delta
1545 + preferred_stack_boundary - 1)
1546 / preferred_stack_boundary
1547 * preferred_stack_boundary)
1548 - stack_pointer_delta);
1550 args_size->constant = MAX (args_size->constant,
1551 reg_parm_stack_space);
1553 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1554 args_size->constant -= reg_parm_stack_space;
1556 return unadjusted_args_size;
1559 /* Precompute parameters as needed for a function call.
1561 FLAGS is mask of ECF_* constants.
1563 NUM_ACTUALS is the number of arguments.
1565 ARGS is an array containing information for each argument; this
1566 routine fills in the INITIAL_VALUE and VALUE fields for each
1567 precomputed argument. */
1570 precompute_arguments (int num_actuals, struct arg_data *args)
1574 /* If this is a libcall, then precompute all arguments so that we do not
1575 get extraneous instructions emitted as part of the libcall sequence. */
1577 /* If we preallocated the stack space, and some arguments must be passed
1578 on the stack, then we must precompute any parameter which contains a
1579 function call which will store arguments on the stack.
1580 Otherwise, evaluating the parameter may clobber previous parameters
1581 which have already been stored into the stack. (we have code to avoid
1582 such case by saving the outgoing stack arguments, but it results in
1584 if (!ACCUMULATE_OUTGOING_ARGS)
1587 for (i = 0; i < num_actuals; i++)
1592 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
1595 /* If this is an addressable type, we cannot pre-evaluate it. */
1596 type = TREE_TYPE (args[i].tree_value);
1597 gcc_assert (!TREE_ADDRESSABLE (type));
1599 args[i].initial_value = args[i].value
1600 = expand_normal (args[i].tree_value);
1602 mode = TYPE_MODE (type);
1603 if (mode != args[i].mode)
1605 int unsignedp = args[i].unsignedp;
1607 = convert_modes (args[i].mode, mode,
1608 args[i].value, args[i].unsignedp);
1610 /* CSE will replace this only if it contains args[i].value
1611 pseudo, so convert it down to the declared mode using
1613 if (REG_P (args[i].value)
1614 && GET_MODE_CLASS (args[i].mode) == MODE_INT
1615 && promote_mode (type, mode, &unsignedp) != args[i].mode)
1617 args[i].initial_value
1618 = gen_lowpart_SUBREG (mode, args[i].value);
1619 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1620 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
1626 /* Given the current state of MUST_PREALLOCATE and information about
1627 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1628 compute and return the final value for MUST_PREALLOCATE. */
1631 finalize_must_preallocate (int must_preallocate, int num_actuals,
1632 struct arg_data *args, struct args_size *args_size)
1634 /* See if we have or want to preallocate stack space.
1636 If we would have to push a partially-in-regs parm
1637 before other stack parms, preallocate stack space instead.
1639 If the size of some parm is not a multiple of the required stack
1640 alignment, we must preallocate.
1642 If the total size of arguments that would otherwise create a copy in
1643 a temporary (such as a CALL) is more than half the total argument list
1644 size, preallocation is faster.
1646 Another reason to preallocate is if we have a machine (like the m88k)
1647 where stack alignment is required to be maintained between every
1648 pair of insns, not just when the call is made. However, we assume here
1649 that such machines either do not have push insns (and hence preallocation
1650 would occur anyway) or the problem is taken care of with
1653 if (! must_preallocate)
1655 int partial_seen = 0;
1656 int copy_to_evaluate_size = 0;
1659 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1661 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1663 else if (partial_seen && args[i].reg == 0)
1664 must_preallocate = 1;
1665 /* We preallocate in case there are bounds passed
1666 in the bounds table to have precomputed address
1667 for bounds association. */
1668 else if (POINTER_BOUNDS_P (args[i].tree_value)
1670 must_preallocate = 1;
1672 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1673 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1674 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1675 || TREE_CODE (args[i].tree_value) == COND_EXPR
1676 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1677 copy_to_evaluate_size
1678 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1681 if (copy_to_evaluate_size * 2 >= args_size->constant
1682 && args_size->constant > 0)
1683 must_preallocate = 1;
1685 return must_preallocate;
1688 /* If we preallocated stack space, compute the address of each argument
1689 and store it into the ARGS array.
1691 We need not ensure it is a valid memory address here; it will be
1692 validized when it is used.
1694 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1697 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1701 rtx arg_reg = argblock;
1702 int i, arg_offset = 0;
1704 if (GET_CODE (argblock) == PLUS)
1705 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1707 for (i = 0; i < num_actuals; i++)
1709 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1710 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1712 unsigned int align, boundary;
1713 unsigned int units_on_stack = 0;
1714 machine_mode partial_mode = VOIDmode;
1716 /* Skip this parm if it will not be passed on the stack. */
1717 if (! args[i].pass_on_stack
1719 && args[i].partial == 0)
1722 /* Pointer Bounds are never passed on the stack. */
1723 if (POINTER_BOUNDS_P (args[i].tree_value))
1726 if (CONST_INT_P (offset))
1727 addr = plus_constant (Pmode, arg_reg, INTVAL (offset));
1729 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1731 addr = plus_constant (Pmode, addr, arg_offset);
1733 if (args[i].partial != 0)
1735 /* Only part of the parameter is being passed on the stack.
1736 Generate a simple memory reference of the correct size. */
1737 units_on_stack = args[i].locate.size.constant;
1738 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1740 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1741 set_mem_size (args[i].stack, units_on_stack);
1745 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1746 set_mem_attributes (args[i].stack,
1747 TREE_TYPE (args[i].tree_value), 1);
1749 align = BITS_PER_UNIT;
1750 boundary = args[i].locate.boundary;
1751 if (args[i].locate.where_pad != downward)
1753 else if (CONST_INT_P (offset))
1755 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1756 align = align & -align;
1758 set_mem_align (args[i].stack, align);
1760 if (CONST_INT_P (slot_offset))
1761 addr = plus_constant (Pmode, arg_reg, INTVAL (slot_offset));
1763 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1765 addr = plus_constant (Pmode, addr, arg_offset);
1767 if (args[i].partial != 0)
1769 /* Only part of the parameter is being passed on the stack.
1770 Generate a simple memory reference of the correct size.
1772 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1773 set_mem_size (args[i].stack_slot, units_on_stack);
1777 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1778 set_mem_attributes (args[i].stack_slot,
1779 TREE_TYPE (args[i].tree_value), 1);
1781 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1783 /* Function incoming arguments may overlap with sibling call
1784 outgoing arguments and we cannot allow reordering of reads
1785 from function arguments with stores to outgoing arguments
1786 of sibling calls. */
1787 set_mem_alias_set (args[i].stack, 0);
1788 set_mem_alias_set (args[i].stack_slot, 0);
1793 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1794 in a call instruction.
1796 FNDECL is the tree node for the target function. For an indirect call
1797 FNDECL will be NULL_TREE.
1799 ADDR is the operand 0 of CALL_EXPR for this call. */
1802 rtx_for_function_call (tree fndecl, tree addr)
1806 /* Get the function to call, in the form of RTL. */
1809 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1810 TREE_USED (fndecl) = 1;
1812 /* Get a SYMBOL_REF rtx for the function address. */
1813 funexp = XEXP (DECL_RTL (fndecl), 0);
1816 /* Generate an rtx (probably a pseudo-register) for the address. */
1819 funexp = expand_normal (addr);
1820 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1825 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
1828 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
1829 or NULL_RTX if none has been scanned yet. */
1830 rtx_insn *scan_start;
1831 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
1832 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
1833 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
1834 with fixed offset, or PC if this is with variable or unknown offset. */
1836 } internal_arg_pointer_exp_state;
1838 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
1840 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
1841 the tail call sequence, starting with first insn that hasn't been
1842 scanned yet, and note for each pseudo on the LHS whether it is based
1843 on crtl->args.internal_arg_pointer or not, and what offset from that
1844 that pointer it has. */
1847 internal_arg_pointer_based_exp_scan (void)
1849 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
1851 if (scan_start == NULL_RTX)
1852 insn = get_insns ();
1854 insn = NEXT_INSN (scan_start);
1858 rtx set = single_set (insn);
1859 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
1862 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
1863 /* Punt on pseudos set multiple times. */
1864 if (idx < internal_arg_pointer_exp_state.cache.length ()
1865 && (internal_arg_pointer_exp_state.cache[idx]
1869 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
1870 if (val != NULL_RTX)
1872 if (idx >= internal_arg_pointer_exp_state.cache.length ())
1873 internal_arg_pointer_exp_state.cache
1874 .safe_grow_cleared (idx + 1);
1875 internal_arg_pointer_exp_state.cache[idx] = val;
1878 if (NEXT_INSN (insn) == NULL_RTX)
1880 insn = NEXT_INSN (insn);
1883 internal_arg_pointer_exp_state.scan_start = scan_start;
1886 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
1887 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
1888 it with fixed offset, or PC if this is with variable or unknown offset.
1889 TOPLEVEL is true if the function is invoked at the topmost level. */
1892 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
1894 if (CONSTANT_P (rtl))
1897 if (rtl == crtl->args.internal_arg_pointer)
1900 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
1903 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
1905 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
1906 if (val == NULL_RTX || val == pc_rtx)
1908 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
1911 /* When called at the topmost level, scan pseudo assignments in between the
1912 last scanned instruction in the tail call sequence and the latest insn
1913 in that sequence. */
1915 internal_arg_pointer_based_exp_scan ();
1919 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
1920 if (idx < internal_arg_pointer_exp_state.cache.length ())
1921 return internal_arg_pointer_exp_state.cache[idx];
1926 subrtx_iterator::array_type array;
1927 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
1929 const_rtx x = *iter;
1930 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
1933 iter.skip_subrtxes ();
1939 /* Return true if and only if SIZE storage units (usually bytes)
1940 starting from address ADDR overlap with already clobbered argument
1941 area. This function is used to determine if we should give up a
1945 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1950 if (bitmap_empty_p (stored_args_map))
1952 val = internal_arg_pointer_based_exp (addr, true);
1953 if (val == NULL_RTX)
1955 else if (val == pc_rtx)
1960 if (STACK_GROWS_DOWNWARD)
1961 i -= crtl->args.pretend_args_size;
1963 i += crtl->args.pretend_args_size;
1966 if (ARGS_GROW_DOWNWARD)
1971 unsigned HOST_WIDE_INT k;
1973 for (k = 0; k < size; k++)
1974 if (i + k < SBITMAP_SIZE (stored_args_map)
1975 && bitmap_bit_p (stored_args_map, i + k))
1982 /* Do the register loads required for any wholly-register parms or any
1983 parms which are passed both on the stack and in a register. Their
1984 expressions were already evaluated.
1986 Mark all register-parms as living through the call, putting these USE
1987 insns in the CALL_INSN_FUNCTION_USAGE field.
1989 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1990 checking, setting *SIBCALL_FAILURE if appropriate. */
1993 load_register_parameters (struct arg_data *args, int num_actuals,
1994 rtx *call_fusage, int flags, int is_sibcall,
1995 int *sibcall_failure)
1999 for (i = 0; i < num_actuals; i++)
2001 rtx reg = ((flags & ECF_SIBCALL)
2002 ? args[i].tail_call_reg : args[i].reg);
2005 int partial = args[i].partial;
2008 rtx_insn *before_arg = get_last_insn ();
2009 /* Set non-negative if we must move a word at a time, even if
2010 just one word (e.g, partial == 4 && mode == DFmode). Set
2011 to -1 if we just use a normal move insn. This value can be
2012 zero if the argument is a zero size structure. */
2014 if (GET_CODE (reg) == PARALLEL)
2018 gcc_assert (partial % UNITS_PER_WORD == 0);
2019 nregs = partial / UNITS_PER_WORD;
2021 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2023 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2024 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2027 size = GET_MODE_SIZE (args[i].mode);
2029 /* Handle calls that pass values in multiple non-contiguous
2030 locations. The Irix 6 ABI has examples of this. */
2032 if (GET_CODE (reg) == PARALLEL)
2033 emit_group_move (reg, args[i].parallel_value);
2035 /* If simple case, just do move. If normal partial, store_one_arg
2036 has already loaded the register for us. In all other cases,
2037 load the register(s) from memory. */
2039 else if (nregs == -1)
2041 emit_move_insn (reg, args[i].value);
2042 #ifdef BLOCK_REG_PADDING
2043 /* Handle case where we have a value that needs shifting
2044 up to the msb. eg. a QImode value and we're padding
2045 upward on a BYTES_BIG_ENDIAN machine. */
2046 if (size < UNITS_PER_WORD
2047 && (args[i].locate.where_pad
2048 == (BYTES_BIG_ENDIAN ? upward : downward)))
2051 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2053 /* Assigning REG here rather than a temp makes CALL_FUSAGE
2054 report the whole reg as used. Strictly speaking, the
2055 call only uses SIZE bytes at the msb end, but it doesn't
2056 seem worth generating rtl to say that. */
2057 reg = gen_rtx_REG (word_mode, REGNO (reg));
2058 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
2060 emit_move_insn (reg, x);
2065 /* If we have pre-computed the values to put in the registers in
2066 the case of non-aligned structures, copy them in now. */
2068 else if (args[i].n_aligned_regs != 0)
2069 for (j = 0; j < args[i].n_aligned_regs; j++)
2070 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2071 args[i].aligned_regs[j]);
2073 else if (partial == 0 || args[i].pass_on_stack)
2075 rtx mem = validize_mem (copy_rtx (args[i].value));
2077 /* Check for overlap with already clobbered argument area,
2078 providing that this has non-zero size. */
2081 || mem_overlaps_already_clobbered_arg_p
2082 (XEXP (args[i].value, 0), size)))
2083 *sibcall_failure = 1;
2085 if (size % UNITS_PER_WORD == 0
2086 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2087 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2091 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2093 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2094 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2095 unsigned int bitsize = size * BITS_PER_UNIT - bitoff;
2096 rtx x = extract_bit_field (mem, bitsize, bitoff, 1,
2097 dest, word_mode, word_mode);
2098 if (BYTES_BIG_ENDIAN)
2099 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2100 BITS_PER_WORD - bitsize, dest, 1);
2102 emit_move_insn (dest, x);
2105 /* Handle a BLKmode that needs shifting. */
2106 if (nregs == 1 && size < UNITS_PER_WORD
2107 #ifdef BLOCK_REG_PADDING
2108 && args[i].locate.where_pad == downward
2114 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2115 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2116 enum tree_code dir = (BYTES_BIG_ENDIAN
2117 ? RSHIFT_EXPR : LSHIFT_EXPR);
2120 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2122 emit_move_insn (dest, x);
2126 /* When a parameter is a block, and perhaps in other cases, it is
2127 possible that it did a load from an argument slot that was
2128 already clobbered. */
2130 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2131 *sibcall_failure = 1;
2133 /* Handle calls that pass values in multiple non-contiguous
2134 locations. The Irix 6 ABI has examples of this. */
2135 if (GET_CODE (reg) == PARALLEL)
2136 use_group_regs (call_fusage, reg);
2137 else if (nregs == -1)
2138 use_reg_mode (call_fusage, reg,
2139 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2141 use_regs (call_fusage, REGNO (reg), nregs);
2146 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2147 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2148 bytes, then we would need to push some additional bytes to pad the
2149 arguments. So, we compute an adjust to the stack pointer for an
2150 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2151 bytes. Then, when the arguments are pushed the stack will be perfectly
2152 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2153 be popped after the call. Returns the adjustment. */
2156 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2157 struct args_size *args_size,
2158 unsigned int preferred_unit_stack_boundary)
2160 /* The number of bytes to pop so that the stack will be
2161 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2162 HOST_WIDE_INT adjustment;
2163 /* The alignment of the stack after the arguments are pushed, if we
2164 just pushed the arguments without adjust the stack here. */
2165 unsigned HOST_WIDE_INT unadjusted_alignment;
2167 unadjusted_alignment
2168 = ((stack_pointer_delta + unadjusted_args_size)
2169 % preferred_unit_stack_boundary);
2171 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2172 as possible -- leaving just enough left to cancel out the
2173 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2174 PENDING_STACK_ADJUST is non-negative, and congruent to
2175 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2177 /* Begin by trying to pop all the bytes. */
2178 unadjusted_alignment
2179 = (unadjusted_alignment
2180 - (pending_stack_adjust % preferred_unit_stack_boundary));
2181 adjustment = pending_stack_adjust;
2182 /* Push enough additional bytes that the stack will be aligned
2183 after the arguments are pushed. */
2184 if (preferred_unit_stack_boundary > 1)
2186 if (unadjusted_alignment > 0)
2187 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2189 adjustment += unadjusted_alignment;
2192 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2193 bytes after the call. The right number is the entire
2194 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2195 by the arguments in the first place. */
2197 = pending_stack_adjust - adjustment + unadjusted_args_size;
2202 /* Scan X expression if it does not dereference any argument slots
2203 we already clobbered by tail call arguments (as noted in stored_args_map
2205 Return nonzero if X expression dereferences such argument slots,
2209 check_sibcall_argument_overlap_1 (rtx x)
2218 code = GET_CODE (x);
2220 /* We need not check the operands of the CALL expression itself. */
2225 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2226 GET_MODE_SIZE (GET_MODE (x)));
2228 /* Scan all subexpressions. */
2229 fmt = GET_RTX_FORMAT (code);
2230 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2234 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2237 else if (*fmt == 'E')
2239 for (j = 0; j < XVECLEN (x, i); j++)
2240 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2247 /* Scan sequence after INSN if it does not dereference any argument slots
2248 we already clobbered by tail call arguments (as noted in stored_args_map
2249 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2250 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2251 should be 0). Return nonzero if sequence after INSN dereferences such argument
2252 slots, zero otherwise. */
2255 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
2256 int mark_stored_args_map)
2260 if (insn == NULL_RTX)
2261 insn = get_insns ();
2263 insn = NEXT_INSN (insn);
2265 for (; insn; insn = NEXT_INSN (insn))
2267 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2270 if (mark_stored_args_map)
2272 if (ARGS_GROW_DOWNWARD)
2273 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2275 low = arg->locate.slot_offset.constant;
2277 for (high = low + arg->locate.size.constant; low < high; low++)
2278 bitmap_set_bit (stored_args_map, low);
2280 return insn != NULL_RTX;
2283 /* Given that a function returns a value of mode MODE at the most
2284 significant end of hard register VALUE, shift VALUE left or right
2285 as specified by LEFT_P. Return true if some action was needed. */
2288 shift_return_value (machine_mode mode, bool left_p, rtx value)
2290 HOST_WIDE_INT shift;
2292 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2293 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2297 /* Use ashr rather than lshr for right shifts. This is for the benefit
2298 of the MIPS port, which requires SImode values to be sign-extended
2299 when stored in 64-bit registers. */
2300 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2301 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2306 /* If X is a likely-spilled register value, copy it to a pseudo
2307 register and return that register. Return X otherwise. */
2310 avoid_likely_spilled_reg (rtx x)
2315 && HARD_REGISTER_P (x)
2316 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2318 /* Make sure that we generate a REG rather than a CONCAT.
2319 Moves into CONCATs can need nontrivial instructions,
2320 and the whole point of this function is to avoid
2321 using the hard register directly in such a situation. */
2322 generating_concat_p = 0;
2323 new_rtx = gen_reg_rtx (GET_MODE (x));
2324 generating_concat_p = 1;
2325 emit_move_insn (new_rtx, x);
2331 /* Generate all the code for a CALL_EXPR exp
2332 and return an rtx for its value.
2333 Store the value in TARGET (specified as an rtx) if convenient.
2334 If the value is stored in TARGET then TARGET is returned.
2335 If IGNORE is nonzero, then we ignore the value of the function call. */
2338 expand_call (tree exp, rtx target, int ignore)
2340 /* Nonzero if we are currently expanding a call. */
2341 static int currently_expanding_call = 0;
2343 /* RTX for the function to be called. */
2345 /* Sequence of insns to perform a normal "call". */
2346 rtx_insn *normal_call_insns = NULL;
2347 /* Sequence of insns to perform a tail "call". */
2348 rtx_insn *tail_call_insns = NULL;
2349 /* Data type of the function. */
2351 tree type_arg_types;
2353 /* Declaration of the function being called,
2354 or 0 if the function is computed (not known by name). */
2356 /* The type of the function being called. */
2358 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2361 /* Register in which non-BLKmode value will be returned,
2362 or 0 if no value or if value is BLKmode. */
2364 /* Register(s) in which bounds are returned. */
2366 /* Address where we should return a BLKmode value;
2367 0 if value not BLKmode. */
2368 rtx structure_value_addr = 0;
2369 /* Nonzero if that address is being passed by treating it as
2370 an extra, implicit first parameter. Otherwise,
2371 it is passed by being copied directly into struct_value_rtx. */
2372 int structure_value_addr_parm = 0;
2373 /* Holds the value of implicit argument for the struct value. */
2374 tree structure_value_addr_value = NULL_TREE;
2375 /* Size of aggregate value wanted, or zero if none wanted
2376 or if we are using the non-reentrant PCC calling convention
2377 or expecting the value in registers. */
2378 HOST_WIDE_INT struct_value_size = 0;
2379 /* Nonzero if called function returns an aggregate in memory PCC style,
2380 by returning the address of where to find it. */
2381 int pcc_struct_value = 0;
2382 rtx struct_value = 0;
2384 /* Number of actual parameters in this call, including struct value addr. */
2386 /* Number of named args. Args after this are anonymous ones
2387 and they must all go on the stack. */
2389 /* Number of complex actual arguments that need to be split. */
2390 int num_complex_actuals = 0;
2392 /* Vector of information about each argument.
2393 Arguments are numbered in the order they will be pushed,
2394 not the order they are written. */
2395 struct arg_data *args;
2397 /* Total size in bytes of all the stack-parms scanned so far. */
2398 struct args_size args_size;
2399 struct args_size adjusted_args_size;
2400 /* Size of arguments before any adjustments (such as rounding). */
2401 int unadjusted_args_size;
2402 /* Data on reg parms scanned so far. */
2403 CUMULATIVE_ARGS args_so_far_v;
2404 cumulative_args_t args_so_far;
2405 /* Nonzero if a reg parm has been scanned. */
2407 /* Nonzero if this is an indirect function call. */
2409 /* Nonzero if we must avoid push-insns in the args for this call.
2410 If stack space is allocated for register parameters, but not by the
2411 caller, then it is preallocated in the fixed part of the stack frame.
2412 So the entire argument block must then be preallocated (i.e., we
2413 ignore PUSH_ROUNDING in that case). */
2415 int must_preallocate = !PUSH_ARGS;
2417 /* Size of the stack reserved for parameter registers. */
2418 int reg_parm_stack_space = 0;
2420 /* Address of space preallocated for stack parms
2421 (on machines that lack push insns), or 0 if space not preallocated. */
2424 /* Mask of ECF_ and ERF_ flags. */
2426 int return_flags = 0;
2427 #ifdef REG_PARM_STACK_SPACE
2428 /* Define the boundary of the register parm stack space that needs to be
2430 int low_to_save, high_to_save;
2431 rtx save_area = 0; /* Place that it is saved */
2434 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2435 char *initial_stack_usage_map = stack_usage_map;
2436 char *stack_usage_map_buf = NULL;
2438 int old_stack_allocated;
2440 /* State variables to track stack modifications. */
2441 rtx old_stack_level = 0;
2442 int old_stack_arg_under_construction = 0;
2443 int old_pending_adj = 0;
2444 int old_inhibit_defer_pop = inhibit_defer_pop;
2446 /* Some stack pointer alterations we make are performed via
2447 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2448 which we then also need to save/restore along the way. */
2449 int old_stack_pointer_delta = 0;
2452 tree addr = CALL_EXPR_FN (exp);
2454 /* The alignment of the stack, in bits. */
2455 unsigned HOST_WIDE_INT preferred_stack_boundary;
2456 /* The alignment of the stack, in bytes. */
2457 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
2458 /* The static chain value to use for this call. */
2459 rtx static_chain_value;
2460 /* See if this is "nothrow" function call. */
2461 if (TREE_NOTHROW (exp))
2462 flags |= ECF_NOTHROW;
2464 /* See if we can find a DECL-node for the actual function, and get the
2465 function attributes (flags) from the function decl or type node. */
2466 fndecl = get_callee_fndecl (exp);
2469 fntype = TREE_TYPE (fndecl);
2470 flags |= flags_from_decl_or_type (fndecl);
2471 return_flags |= decl_return_flags (fndecl);
2475 fntype = TREE_TYPE (TREE_TYPE (addr));
2476 flags |= flags_from_decl_or_type (fntype);
2478 rettype = TREE_TYPE (exp);
2480 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2482 /* Warn if this value is an aggregate type,
2483 regardless of which calling convention we are using for it. */
2484 if (AGGREGATE_TYPE_P (rettype))
2485 warning (OPT_Waggregate_return, "function call has aggregate value");
2487 /* If the result of a non looping pure or const function call is
2488 ignored (or void), and none of its arguments are volatile, we can
2489 avoid expanding the call and just evaluate the arguments for
2491 if ((flags & (ECF_CONST | ECF_PURE))
2492 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
2493 && (ignore || target == const0_rtx
2494 || TYPE_MODE (rettype) == VOIDmode))
2496 bool volatilep = false;
2498 call_expr_arg_iterator iter;
2500 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2501 if (TREE_THIS_VOLATILE (arg))
2509 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2510 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2515 #ifdef REG_PARM_STACK_SPACE
2516 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
2519 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2520 && reg_parm_stack_space > 0 && PUSH_ARGS)
2521 must_preallocate = 1;
2523 /* Set up a place to return a structure. */
2525 /* Cater to broken compilers. */
2526 if (aggregate_value_p (exp, fntype))
2528 /* This call returns a big structure. */
2529 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2531 #ifdef PCC_STATIC_STRUCT_RETURN
2533 pcc_struct_value = 1;
2535 #else /* not PCC_STATIC_STRUCT_RETURN */
2537 struct_value_size = int_size_in_bytes (rettype);
2539 /* Even if it is semantically safe to use the target as the return
2540 slot, it may be not sufficiently aligned for the return type. */
2541 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
2544 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
2545 && SLOW_UNALIGNED_ACCESS (TYPE_MODE (rettype),
2546 MEM_ALIGN (target))))
2547 structure_value_addr = XEXP (target, 0);
2550 /* For variable-sized objects, we must be called with a target
2551 specified. If we were to allocate space on the stack here,
2552 we would have no way of knowing when to free it. */
2553 rtx d = assign_temp (rettype, 1, 1);
2554 structure_value_addr = XEXP (d, 0);
2558 #endif /* not PCC_STATIC_STRUCT_RETURN */
2561 /* Figure out the amount to which the stack should be aligned. */
2562 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2565 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
2566 /* Without automatic stack alignment, we can't increase preferred
2567 stack boundary. With automatic stack alignment, it is
2568 unnecessary since unless we can guarantee that all callers will
2569 align the outgoing stack properly, callee has to align its
2572 && i->preferred_incoming_stack_boundary
2573 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
2574 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2577 /* Operand 0 is a pointer-to-function; get the type of the function. */
2578 funtype = TREE_TYPE (addr);
2579 gcc_assert (POINTER_TYPE_P (funtype));
2580 funtype = TREE_TYPE (funtype);
2582 /* Count whether there are actual complex arguments that need to be split
2583 into their real and imaginary parts. Munge the type_arg_types
2584 appropriately here as well. */
2585 if (targetm.calls.split_complex_arg)
2587 call_expr_arg_iterator iter;
2589 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2591 tree type = TREE_TYPE (arg);
2592 if (type && TREE_CODE (type) == COMPLEX_TYPE
2593 && targetm.calls.split_complex_arg (type))
2594 num_complex_actuals++;
2596 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2599 type_arg_types = TYPE_ARG_TYPES (funtype);
2601 if (flags & ECF_MAY_BE_ALLOCA)
2602 cfun->calls_alloca = 1;
2604 /* If struct_value_rtx is 0, it means pass the address
2605 as if it were an extra parameter. Put the argument expression
2606 in structure_value_addr_value. */
2607 if (structure_value_addr && struct_value == 0)
2609 /* If structure_value_addr is a REG other than
2610 virtual_outgoing_args_rtx, we can use always use it. If it
2611 is not a REG, we must always copy it into a register.
2612 If it is virtual_outgoing_args_rtx, we must copy it to another
2613 register in some cases. */
2614 rtx temp = (!REG_P (structure_value_addr)
2615 || (ACCUMULATE_OUTGOING_ARGS
2616 && stack_arg_under_construction
2617 && structure_value_addr == virtual_outgoing_args_rtx)
2618 ? copy_addr_to_reg (convert_memory_address
2619 (Pmode, structure_value_addr))
2620 : structure_value_addr);
2622 structure_value_addr_value =
2623 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2624 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
2627 /* Count the arguments and set NUM_ACTUALS. */
2629 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2631 /* Compute number of named args.
2632 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2634 if (type_arg_types != 0)
2636 = (list_length (type_arg_types)
2637 /* Count the struct value address, if it is passed as a parm. */
2638 + structure_value_addr_parm);
2640 /* If we know nothing, treat all args as named. */
2641 n_named_args = num_actuals;
2643 /* Start updating where the next arg would go.
2645 On some machines (such as the PA) indirect calls have a different
2646 calling convention than normal calls. The fourth argument in
2647 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2649 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
2650 args_so_far = pack_cumulative_args (&args_so_far_v);
2652 /* Now possibly adjust the number of named args.
2653 Normally, don't include the last named arg if anonymous args follow.
2654 We do include the last named arg if
2655 targetm.calls.strict_argument_naming() returns nonzero.
2656 (If no anonymous args follow, the result of list_length is actually
2657 one too large. This is harmless.)
2659 If targetm.calls.pretend_outgoing_varargs_named() returns
2660 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2661 this machine will be able to place unnamed args that were passed
2662 in registers into the stack. So treat all args as named. This
2663 allows the insns emitting for a specific argument list to be
2664 independent of the function declaration.
2666 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2667 we do not have any reliable way to pass unnamed args in
2668 registers, so we must force them into memory. */
2670 if (type_arg_types != 0
2671 && targetm.calls.strict_argument_naming (args_so_far))
2673 else if (type_arg_types != 0
2674 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
2675 /* Don't include the last named arg. */
2678 /* Treat all args as named. */
2679 n_named_args = num_actuals;
2681 /* Make a vector to hold all the information about each arg. */
2682 args = XALLOCAVEC (struct arg_data, num_actuals);
2683 memset (args, 0, num_actuals * sizeof (struct arg_data));
2685 /* Build up entries in the ARGS array, compute the size of the
2686 arguments into ARGS_SIZE, etc. */
2687 initialize_argument_information (num_actuals, args, &args_size,
2689 structure_value_addr_value, fndecl, fntype,
2690 args_so_far, reg_parm_stack_space,
2691 &old_stack_level, &old_pending_adj,
2692 &must_preallocate, &flags,
2693 &try_tail_call, CALL_FROM_THUNK_P (exp));
2696 must_preallocate = 1;
2698 /* Now make final decision about preallocating stack space. */
2699 must_preallocate = finalize_must_preallocate (must_preallocate,
2703 /* If the structure value address will reference the stack pointer, we
2704 must stabilize it. We don't need to do this if we know that we are
2705 not going to adjust the stack pointer in processing this call. */
2707 if (structure_value_addr
2708 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2709 || reg_mentioned_p (virtual_outgoing_args_rtx,
2710 structure_value_addr))
2712 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2713 structure_value_addr = copy_to_reg (structure_value_addr);
2715 /* Tail calls can make things harder to debug, and we've traditionally
2716 pushed these optimizations into -O2. Don't try if we're already
2717 expanding a call, as that means we're an argument. Don't try if
2718 there's cleanups, as we know there's code to follow the call. */
2720 if (currently_expanding_call++ != 0
2721 || !flag_optimize_sibling_calls
2723 || dbg_cnt (tail_call) == false)
2726 /* Rest of purposes for tail call optimizations to fail. */
2728 || !targetm.have_sibcall_epilogue ()
2729 /* Doing sibling call optimization needs some work, since
2730 structure_value_addr can be allocated on the stack.
2731 It does not seem worth the effort since few optimizable
2732 sibling calls will return a structure. */
2733 || structure_value_addr != NULL_RTX
2734 #ifdef REG_PARM_STACK_SPACE
2735 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2736 || (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2737 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl)))
2738 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl))
2740 /* Check whether the target is able to optimize the call
2742 || !targetm.function_ok_for_sibcall (fndecl, exp)
2743 /* Functions that do not return exactly once may not be sibcall
2745 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2746 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2747 /* If the called function is nested in the current one, it might access
2748 some of the caller's arguments, but could clobber them beforehand if
2749 the argument areas are shared. */
2750 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2751 /* If this function requires more stack slots than the current
2752 function, we cannot change it into a sibling call.
2753 crtl->args.pretend_args_size is not part of the
2754 stack allocated by our caller. */
2755 || args_size.constant > (crtl->args.size
2756 - crtl->args.pretend_args_size)
2757 /* If the callee pops its own arguments, then it must pop exactly
2758 the same number of arguments as the current function. */
2759 || (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2760 != targetm.calls.return_pops_args (current_function_decl,
2761 TREE_TYPE (current_function_decl),
2763 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2766 /* Check if caller and callee disagree in promotion of function
2770 machine_mode caller_mode, caller_promoted_mode;
2771 machine_mode callee_mode, callee_promoted_mode;
2772 int caller_unsignedp, callee_unsignedp;
2773 tree caller_res = DECL_RESULT (current_function_decl);
2775 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
2776 caller_mode = DECL_MODE (caller_res);
2777 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
2778 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
2779 caller_promoted_mode
2780 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
2782 TREE_TYPE (current_function_decl), 1);
2783 callee_promoted_mode
2784 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
2787 if (caller_mode != VOIDmode
2788 && (caller_promoted_mode != callee_promoted_mode
2789 || ((caller_mode != caller_promoted_mode
2790 || callee_mode != callee_promoted_mode)
2791 && (caller_unsignedp != callee_unsignedp
2792 || GET_MODE_BITSIZE (caller_mode)
2793 < GET_MODE_BITSIZE (callee_mode)))))
2797 /* Ensure current function's preferred stack boundary is at least
2798 what we need. Stack alignment may also increase preferred stack
2800 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
2801 crtl->preferred_stack_boundary = preferred_stack_boundary;
2803 preferred_stack_boundary = crtl->preferred_stack_boundary;
2805 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2807 /* We want to make two insn chains; one for a sibling call, the other
2808 for a normal call. We will select one of the two chains after
2809 initial RTL generation is complete. */
2810 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2812 int sibcall_failure = 0;
2813 /* We want to emit any pending stack adjustments before the tail
2814 recursion "call". That way we know any adjustment after the tail
2815 recursion call can be ignored if we indeed use the tail
2817 saved_pending_stack_adjust save;
2818 rtx_insn *insns, *before_call, *after_args;
2823 /* State variables we need to save and restore between
2825 save_pending_stack_adjust (&save);
2828 flags &= ~ECF_SIBCALL;
2830 flags |= ECF_SIBCALL;
2832 /* Other state variables that we must reinitialize each time
2833 through the loop (that are not initialized by the loop itself). */
2837 /* Start a new sequence for the normal call case.
2839 From this point on, if the sibling call fails, we want to set
2840 sibcall_failure instead of continuing the loop. */
2843 /* Don't let pending stack adjusts add up to too much.
2844 Also, do all pending adjustments now if there is any chance
2845 this might be a call to alloca or if we are expanding a sibling
2847 Also do the adjustments before a throwing call, otherwise
2848 exception handling can fail; PR 19225. */
2849 if (pending_stack_adjust >= 32
2850 || (pending_stack_adjust > 0
2851 && (flags & ECF_MAY_BE_ALLOCA))
2852 || (pending_stack_adjust > 0
2853 && flag_exceptions && !(flags & ECF_NOTHROW))
2855 do_pending_stack_adjust ();
2857 /* Precompute any arguments as needed. */
2859 precompute_arguments (num_actuals, args);
2861 /* Now we are about to start emitting insns that can be deleted
2862 if a libcall is deleted. */
2863 if (pass && (flags & ECF_MALLOC))
2866 if (pass == 0 && crtl->stack_protect_guard)
2867 stack_protect_epilogue ();
2869 adjusted_args_size = args_size;
2870 /* Compute the actual size of the argument block required. The variable
2871 and constant sizes must be combined, the size may have to be rounded,
2872 and there may be a minimum required size. When generating a sibcall
2873 pattern, do not round up, since we'll be re-using whatever space our
2875 unadjusted_args_size
2876 = compute_argument_block_size (reg_parm_stack_space,
2877 &adjusted_args_size,
2880 : preferred_stack_boundary));
2882 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2884 /* The argument block when performing a sibling call is the
2885 incoming argument block. */
2888 argblock = crtl->args.internal_arg_pointer;
2889 if (STACK_GROWS_DOWNWARD)
2891 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
2894 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
2896 stored_args_map = sbitmap_alloc (args_size.constant);
2897 bitmap_clear (stored_args_map);
2900 /* If we have no actual push instructions, or shouldn't use them,
2901 make space for all args right now. */
2902 else if (adjusted_args_size.var != 0)
2904 if (old_stack_level == 0)
2906 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2907 old_stack_pointer_delta = stack_pointer_delta;
2908 old_pending_adj = pending_stack_adjust;
2909 pending_stack_adjust = 0;
2910 /* stack_arg_under_construction says whether a stack arg is
2911 being constructed at the old stack level. Pushing the stack
2912 gets a clean outgoing argument block. */
2913 old_stack_arg_under_construction = stack_arg_under_construction;
2914 stack_arg_under_construction = 0;
2916 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2917 if (flag_stack_usage_info)
2918 current_function_has_unbounded_dynamic_stack_size = 1;
2922 /* Note that we must go through the motions of allocating an argument
2923 block even if the size is zero because we may be storing args
2924 in the area reserved for register arguments, which may be part of
2927 int needed = adjusted_args_size.constant;
2929 /* Store the maximum argument space used. It will be pushed by
2930 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2933 if (needed > crtl->outgoing_args_size)
2934 crtl->outgoing_args_size = needed;
2936 if (must_preallocate)
2938 if (ACCUMULATE_OUTGOING_ARGS)
2940 /* Since the stack pointer will never be pushed, it is
2941 possible for the evaluation of a parm to clobber
2942 something we have already written to the stack.
2943 Since most function calls on RISC machines do not use
2944 the stack, this is uncommon, but must work correctly.
2946 Therefore, we save any area of the stack that was already
2947 written and that we are using. Here we set up to do this
2948 by making a new stack usage map from the old one. The
2949 actual save will be done by store_one_arg.
2951 Another approach might be to try to reorder the argument
2952 evaluations to avoid this conflicting stack usage. */
2954 /* Since we will be writing into the entire argument area,
2955 the map must be allocated for its entire size, not just
2956 the part that is the responsibility of the caller. */
2957 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2958 needed += reg_parm_stack_space;
2960 if (ARGS_GROW_DOWNWARD)
2961 highest_outgoing_arg_in_use
2962 = MAX (initial_highest_arg_in_use, needed + 1);
2964 highest_outgoing_arg_in_use
2965 = MAX (initial_highest_arg_in_use, needed);
2967 free (stack_usage_map_buf);
2968 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
2969 stack_usage_map = stack_usage_map_buf;
2971 if (initial_highest_arg_in_use)
2972 memcpy (stack_usage_map, initial_stack_usage_map,
2973 initial_highest_arg_in_use);
2975 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2976 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2977 (highest_outgoing_arg_in_use
2978 - initial_highest_arg_in_use));
2981 /* The address of the outgoing argument list must not be
2982 copied to a register here, because argblock would be left
2983 pointing to the wrong place after the call to
2984 allocate_dynamic_stack_space below. */
2986 argblock = virtual_outgoing_args_rtx;
2990 if (inhibit_defer_pop == 0)
2992 /* Try to reuse some or all of the pending_stack_adjust
2993 to get this space. */
2995 = (combine_pending_stack_adjustment_and_call
2996 (unadjusted_args_size,
2997 &adjusted_args_size,
2998 preferred_unit_stack_boundary));
3000 /* combine_pending_stack_adjustment_and_call computes
3001 an adjustment before the arguments are allocated.
3002 Account for them and see whether or not the stack
3003 needs to go up or down. */
3004 needed = unadjusted_args_size - needed;
3008 /* We're releasing stack space. */
3009 /* ??? We can avoid any adjustment at all if we're
3010 already aligned. FIXME. */
3011 pending_stack_adjust = -needed;
3012 do_pending_stack_adjust ();
3016 /* We need to allocate space. We'll do that in
3017 push_block below. */
3018 pending_stack_adjust = 0;
3021 /* Special case this because overhead of `push_block' in
3022 this case is non-trivial. */
3024 argblock = virtual_outgoing_args_rtx;
3027 argblock = push_block (GEN_INT (needed), 0, 0);
3028 if (ARGS_GROW_DOWNWARD)
3029 argblock = plus_constant (Pmode, argblock, needed);
3032 /* We only really need to call `copy_to_reg' in the case
3033 where push insns are going to be used to pass ARGBLOCK
3034 to a function call in ARGS. In that case, the stack
3035 pointer changes value from the allocation point to the
3036 call point, and hence the value of
3037 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3038 as well always do it. */
3039 argblock = copy_to_reg (argblock);
3044 if (ACCUMULATE_OUTGOING_ARGS)
3046 /* The save/restore code in store_one_arg handles all
3047 cases except one: a constructor call (including a C
3048 function returning a BLKmode struct) to initialize
3050 if (stack_arg_under_construction)
3053 = GEN_INT (adjusted_args_size.constant
3054 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
3055 : TREE_TYPE (fndecl))) ? 0
3056 : reg_parm_stack_space));
3057 if (old_stack_level == 0)
3059 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3060 old_stack_pointer_delta = stack_pointer_delta;
3061 old_pending_adj = pending_stack_adjust;
3062 pending_stack_adjust = 0;
3063 /* stack_arg_under_construction says whether a stack
3064 arg is being constructed at the old stack level.
3065 Pushing the stack gets a clean outgoing argument
3067 old_stack_arg_under_construction
3068 = stack_arg_under_construction;
3069 stack_arg_under_construction = 0;
3070 /* Make a new map for the new argument list. */
3071 free (stack_usage_map_buf);
3072 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3073 stack_usage_map = stack_usage_map_buf;
3074 highest_outgoing_arg_in_use = 0;
3076 /* We can pass TRUE as the 4th argument because we just
3077 saved the stack pointer and will restore it right after
3079 allocate_dynamic_stack_space (push_size, 0,
3080 BIGGEST_ALIGNMENT, true);
3083 /* If argument evaluation might modify the stack pointer,
3084 copy the address of the argument list to a register. */
3085 for (i = 0; i < num_actuals; i++)
3086 if (args[i].pass_on_stack)
3088 argblock = copy_addr_to_reg (argblock);
3093 compute_argument_addresses (args, argblock, num_actuals);
3095 /* Stack is properly aligned, pops can't safely be deferred during
3096 the evaluation of the arguments. */
3099 /* Precompute all register parameters. It isn't safe to compute
3100 anything once we have started filling any specific hard regs.
3101 TLS symbols sometimes need a call to resolve. Precompute
3102 register parameters before any stack pointer manipulation
3103 to avoid unaligned stack in the called function. */
3104 precompute_register_parameters (num_actuals, args, ®_parm_seen);
3108 /* Perform stack alignment before the first push (the last arg). */
3110 && adjusted_args_size.constant > reg_parm_stack_space
3111 && adjusted_args_size.constant != unadjusted_args_size)
3113 /* When the stack adjustment is pending, we get better code
3114 by combining the adjustments. */
3115 if (pending_stack_adjust
3116 && ! inhibit_defer_pop)
3118 pending_stack_adjust
3119 = (combine_pending_stack_adjustment_and_call
3120 (unadjusted_args_size,
3121 &adjusted_args_size,
3122 preferred_unit_stack_boundary));
3123 do_pending_stack_adjust ();
3125 else if (argblock == 0)
3126 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3127 - unadjusted_args_size));
3129 /* Now that the stack is properly aligned, pops can't safely
3130 be deferred during the evaluation of the arguments. */
3133 /* Record the maximum pushed stack space size. We need to delay
3134 doing it this far to take into account the optimization done
3135 by combine_pending_stack_adjustment_and_call. */
3136 if (flag_stack_usage_info
3137 && !ACCUMULATE_OUTGOING_ARGS
3139 && adjusted_args_size.var == 0)
3141 int pushed = adjusted_args_size.constant + pending_stack_adjust;
3142 if (pushed > current_function_pushed_stack_size)
3143 current_function_pushed_stack_size = pushed;
3146 funexp = rtx_for_function_call (fndecl, addr);
3148 if (CALL_EXPR_STATIC_CHAIN (exp))
3149 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3151 static_chain_value = 0;
3153 #ifdef REG_PARM_STACK_SPACE
3154 /* Save the fixed argument area if it's part of the caller's frame and
3155 is clobbered by argument setup for this call. */
3156 if (ACCUMULATE_OUTGOING_ARGS && pass)
3157 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3158 &low_to_save, &high_to_save);
3161 /* Now store (and compute if necessary) all non-register parms.
3162 These come before register parms, since they can require block-moves,
3163 which could clobber the registers used for register parms.
3164 Parms which have partial registers are not stored here,
3165 but we do preallocate space here if they want that. */
3167 for (i = 0; i < num_actuals; i++)
3169 /* Delay bounds until all other args are stored. */
3170 if (POINTER_BOUNDS_P (args[i].tree_value))
3172 else if (args[i].reg == 0 || args[i].pass_on_stack)
3174 rtx_insn *before_arg = get_last_insn ();
3176 /* We don't allow passing huge (> 2^30 B) arguments
3177 by value. It would cause an overflow later on. */
3178 if (adjusted_args_size.constant
3179 >= (1 << (HOST_BITS_PER_INT - 2)))
3181 sorry ("passing too large argument on stack");
3185 if (store_one_arg (&args[i], argblock, flags,
3186 adjusted_args_size.var != 0,
3187 reg_parm_stack_space)
3189 && check_sibcall_argument_overlap (before_arg,
3191 sibcall_failure = 1;
3196 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3197 gen_rtx_USE (VOIDmode, args[i].stack),
3201 /* If we have a parm that is passed in registers but not in memory
3202 and whose alignment does not permit a direct copy into registers,
3203 make a group of pseudos that correspond to each register that we
3205 if (STRICT_ALIGNMENT)
3206 store_unaligned_arguments_into_pseudos (args, num_actuals);
3208 /* Now store any partially-in-registers parm.
3209 This is the last place a block-move can happen. */
3211 for (i = 0; i < num_actuals; i++)
3212 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3214 rtx_insn *before_arg = get_last_insn ();
3216 /* On targets with weird calling conventions (e.g. PA) it's
3217 hard to ensure that all cases of argument overlap between
3218 stack and registers work. Play it safe and bail out. */
3219 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
3221 sibcall_failure = 1;
3225 if (store_one_arg (&args[i], argblock, flags,
3226 adjusted_args_size.var != 0,
3227 reg_parm_stack_space)
3229 && check_sibcall_argument_overlap (before_arg,
3231 sibcall_failure = 1;
3234 bool any_regs = false;
3235 for (i = 0; i < num_actuals; i++)
3236 if (args[i].reg != NULL_RTX)
3239 targetm.calls.call_args (args[i].reg, funtype);
3242 targetm.calls.call_args (pc_rtx, funtype);
3244 /* Figure out the register where the value, if any, will come back. */
3247 if (TYPE_MODE (rettype) != VOIDmode
3248 && ! structure_value_addr)
3250 if (pcc_struct_value)
3252 valreg = hard_function_value (build_pointer_type (rettype),
3253 fndecl, NULL, (pass == 0));
3254 if (CALL_WITH_BOUNDS_P (exp))
3255 valbnd = targetm.calls.
3256 chkp_function_value_bounds (build_pointer_type (rettype),
3257 fndecl, (pass == 0));
3261 valreg = hard_function_value (rettype, fndecl, fntype,
3263 if (CALL_WITH_BOUNDS_P (exp))
3264 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
3269 /* If VALREG is a PARALLEL whose first member has a zero
3270 offset, use that. This is for targets such as m68k that
3271 return the same value in multiple places. */
3272 if (GET_CODE (valreg) == PARALLEL)
3274 rtx elem = XVECEXP (valreg, 0, 0);
3275 rtx where = XEXP (elem, 0);
3276 rtx offset = XEXP (elem, 1);
3277 if (offset == const0_rtx
3278 && GET_MODE (where) == GET_MODE (valreg))
3283 /* Store all bounds not passed in registers. */
3284 for (i = 0; i < num_actuals; i++)
3286 if (POINTER_BOUNDS_P (args[i].tree_value)
3288 store_bounds (&args[i],
3289 args[i].pointer_arg == -1
3291 : &args[args[i].pointer_arg]);
3294 /* If register arguments require space on the stack and stack space
3295 was not preallocated, allocate stack space here for arguments
3296 passed in registers. */
3297 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3298 && !ACCUMULATE_OUTGOING_ARGS
3299 && must_preallocate == 0 && reg_parm_stack_space > 0)
3300 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3302 /* Pass the function the address in which to return a
3304 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3306 structure_value_addr
3307 = convert_memory_address (Pmode, structure_value_addr);
3308 emit_move_insn (struct_value,
3310 force_operand (structure_value_addr,
3313 if (REG_P (struct_value))
3314 use_reg (&call_fusage, struct_value);
3317 after_args = get_last_insn ();
3318 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
3319 static_chain_value, &call_fusage,
3320 reg_parm_seen, pass == 0);
3322 load_register_parameters (args, num_actuals, &call_fusage, flags,
3323 pass == 0, &sibcall_failure);
3325 /* Save a pointer to the last insn before the call, so that we can
3326 later safely search backwards to find the CALL_INSN. */
3327 before_call = get_last_insn ();
3329 /* Set up next argument register. For sibling calls on machines
3330 with register windows this should be the incoming register. */
3332 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3337 next_arg_reg = targetm.calls.function_arg (args_so_far,
3338 VOIDmode, void_type_node,
3341 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
3343 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
3344 arg_nr = num_actuals - arg_nr - 1;
3346 && arg_nr < num_actuals
3350 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
3352 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
3353 gen_rtx_SET (valreg, args[arg_nr].reg),
3356 /* All arguments and registers used for the call must be set up by
3359 /* Stack must be properly aligned now. */
3361 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3363 /* Generate the actual call instruction. */
3364 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3365 adjusted_args_size.constant, struct_value_size,
3366 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3367 flags, args_so_far);
3371 rtx_call_insn *last;
3372 rtx datum = NULL_RTX;
3373 if (fndecl != NULL_TREE)
3375 datum = XEXP (DECL_RTL (fndecl), 0);
3376 gcc_assert (datum != NULL_RTX
3377 && GET_CODE (datum) == SYMBOL_REF);
3379 last = last_call_insn ();
3380 add_reg_note (last, REG_CALL_DECL, datum);
3383 /* If the call setup or the call itself overlaps with anything
3384 of the argument setup we probably clobbered our call address.
3385 In that case we can't do sibcalls. */
3387 && check_sibcall_argument_overlap (after_args, 0, 0))
3388 sibcall_failure = 1;
3390 /* If a non-BLKmode value is returned at the most significant end
3391 of a register, shift the register right by the appropriate amount
3392 and update VALREG accordingly. BLKmode values are handled by the
3393 group load/store machinery below. */
3394 if (!structure_value_addr
3395 && !pcc_struct_value
3396 && TYPE_MODE (rettype) != VOIDmode
3397 && TYPE_MODE (rettype) != BLKmode
3399 && targetm.calls.return_in_msb (rettype))
3401 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3402 sibcall_failure = 1;
3403 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3406 if (pass && (flags & ECF_MALLOC))
3408 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3409 rtx_insn *last, *insns;
3411 /* The return value from a malloc-like function is a pointer. */
3412 if (TREE_CODE (rettype) == POINTER_TYPE)
3413 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
3415 emit_move_insn (temp, valreg);
3417 /* The return value from a malloc-like function can not alias
3419 last = get_last_insn ();
3420 add_reg_note (last, REG_NOALIAS, temp);
3422 /* Write out the sequence. */
3423 insns = get_insns ();
3429 /* For calls to `setjmp', etc., inform
3430 function.c:setjmp_warnings that it should complain if
3431 nonvolatile values are live. For functions that cannot
3432 return, inform flow that control does not fall through. */
3434 if ((flags & ECF_NORETURN) || pass == 0)
3436 /* The barrier must be emitted
3437 immediately after the CALL_INSN. Some ports emit more
3438 than just a CALL_INSN above, so we must search for it here. */
3440 rtx_insn *last = get_last_insn ();
3441 while (!CALL_P (last))
3443 last = PREV_INSN (last);
3444 /* There was no CALL_INSN? */
3445 gcc_assert (last != before_call);
3448 emit_barrier_after (last);
3450 /* Stack adjustments after a noreturn call are dead code.
3451 However when NO_DEFER_POP is in effect, we must preserve
3452 stack_pointer_delta. */
3453 if (inhibit_defer_pop == 0)
3455 stack_pointer_delta = old_stack_allocated;
3456 pending_stack_adjust = 0;
3460 /* If value type not void, return an rtx for the value. */
3462 if (TYPE_MODE (rettype) == VOIDmode
3464 target = const0_rtx;
3465 else if (structure_value_addr)
3467 if (target == 0 || !MEM_P (target))
3470 = gen_rtx_MEM (TYPE_MODE (rettype),
3471 memory_address (TYPE_MODE (rettype),
3472 structure_value_addr));
3473 set_mem_attributes (target, rettype, 1);
3476 else if (pcc_struct_value)
3478 /* This is the special C++ case where we need to
3479 know what the true target was. We take care to
3480 never use this value more than once in one expression. */
3481 target = gen_rtx_MEM (TYPE_MODE (rettype),
3482 copy_to_reg (valreg));
3483 set_mem_attributes (target, rettype, 1);
3485 /* Handle calls that return values in multiple non-contiguous locations.
3486 The Irix 6 ABI has examples of this. */
3487 else if (GET_CODE (valreg) == PARALLEL)
3490 target = emit_group_move_into_temps (valreg);
3491 else if (rtx_equal_p (target, valreg))
3493 else if (GET_CODE (target) == PARALLEL)
3494 /* Handle the result of a emit_group_move_into_temps
3495 call in the previous pass. */
3496 emit_group_move (target, valreg);
3498 emit_group_store (target, valreg, rettype,
3499 int_size_in_bytes (rettype));
3502 && GET_MODE (target) == TYPE_MODE (rettype)
3503 && GET_MODE (target) == GET_MODE (valreg))
3505 bool may_overlap = false;
3507 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3508 reg to a plain register. */
3509 if (!REG_P (target) || HARD_REGISTER_P (target))
3510 valreg = avoid_likely_spilled_reg (valreg);
3512 /* If TARGET is a MEM in the argument area, and we have
3513 saved part of the argument area, then we can't store
3514 directly into TARGET as it may get overwritten when we
3515 restore the argument save area below. Don't work too
3516 hard though and simply force TARGET to a register if it
3517 is a MEM; the optimizer is quite likely to sort it out. */
3518 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
3519 for (i = 0; i < num_actuals; i++)
3520 if (args[i].save_area)
3527 target = copy_to_reg (valreg);
3530 /* TARGET and VALREG cannot be equal at this point
3531 because the latter would not have
3532 REG_FUNCTION_VALUE_P true, while the former would if
3533 it were referring to the same register.
3535 If they refer to the same register, this move will be
3536 a no-op, except when function inlining is being
3538 emit_move_insn (target, valreg);
3540 /* If we are setting a MEM, this code must be executed.
3541 Since it is emitted after the call insn, sibcall
3542 optimization cannot be performed in that case. */
3544 sibcall_failure = 1;
3548 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3550 /* If we promoted this return value, make the proper SUBREG.
3551 TARGET might be const0_rtx here, so be careful. */
3553 && TYPE_MODE (rettype) != BLKmode
3554 && GET_MODE (target) != TYPE_MODE (rettype))
3556 tree type = rettype;
3557 int unsignedp = TYPE_UNSIGNED (type);
3561 /* Ensure we promote as expected, and get the new unsignedness. */
3562 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
3564 gcc_assert (GET_MODE (target) == pmode);
3566 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3567 && (GET_MODE_SIZE (GET_MODE (target))
3568 > GET_MODE_SIZE (TYPE_MODE (type))))
3570 offset = GET_MODE_SIZE (GET_MODE (target))
3571 - GET_MODE_SIZE (TYPE_MODE (type));
3572 if (! BYTES_BIG_ENDIAN)
3573 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3574 else if (! WORDS_BIG_ENDIAN)
3575 offset %= UNITS_PER_WORD;
3578 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3579 SUBREG_PROMOTED_VAR_P (target) = 1;
3580 SUBREG_PROMOTED_SET (target, unsignedp);
3583 /* If size of args is variable or this was a constructor call for a stack
3584 argument, restore saved stack-pointer value. */
3586 if (old_stack_level)
3588 rtx_insn *prev = get_last_insn ();
3590 emit_stack_restore (SAVE_BLOCK, old_stack_level);
3591 stack_pointer_delta = old_stack_pointer_delta;
3593 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
3595 pending_stack_adjust = old_pending_adj;
3596 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3597 stack_arg_under_construction = old_stack_arg_under_construction;
3598 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3599 stack_usage_map = initial_stack_usage_map;
3600 sibcall_failure = 1;
3602 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3604 #ifdef REG_PARM_STACK_SPACE
3606 restore_fixed_argument_area (save_area, argblock,
3607 high_to_save, low_to_save);
3610 /* If we saved any argument areas, restore them. */
3611 for (i = 0; i < num_actuals; i++)
3612 if (args[i].save_area)
3614 machine_mode save_mode = GET_MODE (args[i].save_area);
3616 = gen_rtx_MEM (save_mode,
3617 memory_address (save_mode,
3618 XEXP (args[i].stack_slot, 0)));
3620 if (save_mode != BLKmode)
3621 emit_move_insn (stack_area, args[i].save_area);
3623 emit_block_move (stack_area, args[i].save_area,
3624 GEN_INT (args[i].locate.size.constant),
3625 BLOCK_OP_CALL_PARM);
3628 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3629 stack_usage_map = initial_stack_usage_map;
3632 /* If this was alloca, record the new stack level. */
3633 if (flags & ECF_MAY_BE_ALLOCA)
3634 record_new_stack_level ();
3636 /* Free up storage we no longer need. */
3637 for (i = 0; i < num_actuals; ++i)
3638 free (args[i].aligned_regs);
3640 targetm.calls.end_call_args ();
3642 insns = get_insns ();
3647 tail_call_insns = insns;
3649 /* Restore the pending stack adjustment now that we have
3650 finished generating the sibling call sequence. */
3652 restore_pending_stack_adjust (&save);
3654 /* Prepare arg structure for next iteration. */
3655 for (i = 0; i < num_actuals; i++)
3658 args[i].aligned_regs = 0;
3662 sbitmap_free (stored_args_map);
3663 internal_arg_pointer_exp_state.scan_start = NULL;
3664 internal_arg_pointer_exp_state.cache.release ();
3668 normal_call_insns = insns;
3670 /* Verify that we've deallocated all the stack we used. */
3671 gcc_assert ((flags & ECF_NORETURN)
3672 || (old_stack_allocated
3673 == stack_pointer_delta - pending_stack_adjust));
3676 /* If something prevents making this a sibling call,
3677 zero out the sequence. */
3678 if (sibcall_failure)
3679 tail_call_insns = NULL;
3684 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3685 arguments too, as argument area is now clobbered by the call. */
3686 if (tail_call_insns)
3688 emit_insn (tail_call_insns);
3689 crtl->tail_call_emit = true;
3692 emit_insn (normal_call_insns);
3694 currently_expanding_call--;
3696 free (stack_usage_map_buf);
3698 /* Join result with returned bounds so caller may use them if needed. */
3699 target = chkp_join_splitted_slot (target, valbnd);
3704 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3705 this function's incoming arguments.
3707 At the start of RTL generation we know the only REG_EQUIV notes
3708 in the rtl chain are those for incoming arguments, so we can look
3709 for REG_EQUIV notes between the start of the function and the
3710 NOTE_INSN_FUNCTION_BEG.
3712 This is (slight) overkill. We could keep track of the highest
3713 argument we clobber and be more selective in removing notes, but it
3714 does not seem to be worth the effort. */
3717 fixup_tail_calls (void)
3721 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3725 /* There are never REG_EQUIV notes for the incoming arguments
3726 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3728 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3731 note = find_reg_note (insn, REG_EQUIV, 0);
3733 remove_note (insn, note);
3734 note = find_reg_note (insn, REG_EQUIV, 0);
3739 /* Traverse a list of TYPES and expand all complex types into their
3742 split_complex_types (tree types)
3746 /* Before allocating memory, check for the common case of no complex. */
3747 for (p = types; p; p = TREE_CHAIN (p))
3749 tree type = TREE_VALUE (p);
3750 if (TREE_CODE (type) == COMPLEX_TYPE
3751 && targetm.calls.split_complex_arg (type))
3757 types = copy_list (types);
3759 for (p = types; p; p = TREE_CHAIN (p))
3761 tree complex_type = TREE_VALUE (p);
3763 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3764 && targetm.calls.split_complex_arg (complex_type))
3768 /* Rewrite complex type with component type. */
3769 TREE_VALUE (p) = TREE_TYPE (complex_type);
3770 next = TREE_CHAIN (p);
3772 /* Add another component type for the imaginary part. */
3773 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3774 TREE_CHAIN (p) = imag;
3775 TREE_CHAIN (imag) = next;
3777 /* Skip the newly created node. */
3785 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3786 The RETVAL parameter specifies whether return value needs to be saved, other
3787 parameters are documented in the emit_library_call function below. */
3790 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3791 enum libcall_type fn_type,
3792 machine_mode outmode, int nargs, va_list p)
3794 /* Total size in bytes of all the stack-parms scanned so far. */
3795 struct args_size args_size;
3796 /* Size of arguments before any adjustments (such as rounding). */
3797 struct args_size original_args_size;
3800 /* Todo, choose the correct decl type of orgfun. Sadly this information
3801 isn't present here, so we default to native calling abi here. */
3802 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3803 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3806 CUMULATIVE_ARGS args_so_far_v;
3807 cumulative_args_t args_so_far;
3814 struct locate_and_pad_arg_data locate;
3818 int old_inhibit_defer_pop = inhibit_defer_pop;
3819 rtx call_fusage = 0;
3822 int pcc_struct_value = 0;
3823 int struct_value_size = 0;
3825 int reg_parm_stack_space = 0;
3827 rtx_insn *before_call;
3828 bool have_push_fusage;
3829 tree tfom; /* type_for_mode (outmode, 0) */
3831 #ifdef REG_PARM_STACK_SPACE
3832 /* Define the boundary of the register parm stack space that needs to be
3834 int low_to_save = 0, high_to_save = 0;
3835 rtx save_area = 0; /* Place that it is saved. */
3838 /* Size of the stack reserved for parameter registers. */
3839 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3840 char *initial_stack_usage_map = stack_usage_map;
3841 char *stack_usage_map_buf = NULL;
3843 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3845 #ifdef REG_PARM_STACK_SPACE
3846 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3849 /* By default, library functions can not throw. */
3850 flags = ECF_NOTHROW;
3863 flags |= ECF_NORETURN;
3866 flags = ECF_NORETURN;
3868 case LCT_RETURNS_TWICE:
3869 flags = ECF_RETURNS_TWICE;
3874 /* Ensure current function's preferred stack boundary is at least
3876 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3877 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3879 /* If this kind of value comes back in memory,
3880 decide where in memory it should come back. */
3881 if (outmode != VOIDmode)
3883 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3884 if (aggregate_value_p (tfom, 0))
3886 #ifdef PCC_STATIC_STRUCT_RETURN
3888 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3889 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3890 pcc_struct_value = 1;
3892 value = gen_reg_rtx (outmode);
3893 #else /* not PCC_STATIC_STRUCT_RETURN */
3894 struct_value_size = GET_MODE_SIZE (outmode);
3895 if (value != 0 && MEM_P (value))
3898 mem_value = assign_temp (tfom, 1, 1);
3900 /* This call returns a big structure. */
3901 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3905 tfom = void_type_node;
3907 /* ??? Unfinished: must pass the memory address as an argument. */
3909 /* Copy all the libcall-arguments out of the varargs data
3910 and into a vector ARGVEC.
3912 Compute how to pass each argument. We only support a very small subset
3913 of the full argument passing conventions to limit complexity here since
3914 library functions shouldn't have many args. */
3916 argvec = XALLOCAVEC (struct arg, nargs + 1);
3917 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3919 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3920 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
3922 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
3924 args_so_far = pack_cumulative_args (&args_so_far_v);
3926 args_size.constant = 0;
3933 /* If there's a structure value address to be passed,
3934 either pass it in the special place, or pass it as an extra argument. */
3935 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3937 rtx addr = XEXP (mem_value, 0);
3941 /* Make sure it is a reasonable operand for a move or push insn. */
3942 if (!REG_P (addr) && !MEM_P (addr)
3943 && !(CONSTANT_P (addr)
3944 && targetm.legitimate_constant_p (Pmode, addr)))
3945 addr = force_operand (addr, NULL_RTX);
3947 argvec[count].value = addr;
3948 argvec[count].mode = Pmode;
3949 argvec[count].partial = 0;
3951 argvec[count].reg = targetm.calls.function_arg (args_so_far,
3952 Pmode, NULL_TREE, true);
3953 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
3954 NULL_TREE, 1) == 0);
3956 locate_and_pad_parm (Pmode, NULL_TREE,
3957 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3960 argvec[count].reg != 0,
3962 reg_parm_stack_space, 0,
3963 NULL_TREE, &args_size, &argvec[count].locate);
3965 if (argvec[count].reg == 0 || argvec[count].partial != 0
3966 || reg_parm_stack_space > 0)
3967 args_size.constant += argvec[count].locate.size.constant;
3969 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
3974 for (; count < nargs; count++)
3976 rtx val = va_arg (p, rtx);
3977 machine_mode mode = (machine_mode) va_arg (p, int);
3980 /* We cannot convert the arg value to the mode the library wants here;
3981 must do it earlier where we know the signedness of the arg. */
3982 gcc_assert (mode != BLKmode
3983 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
3985 /* Make sure it is a reasonable operand for a move or push insn. */
3986 if (!REG_P (val) && !MEM_P (val)
3987 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
3988 val = force_operand (val, NULL_RTX);
3990 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
3994 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
3996 /* If this was a CONST function, it is now PURE since it now
3998 if (flags & ECF_CONST)
4000 flags &= ~ECF_CONST;
4004 if (MEM_P (val) && !must_copy)
4006 tree val_expr = MEM_EXPR (val);
4008 mark_addressable (val_expr);
4013 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4015 emit_move_insn (slot, val);
4018 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4019 gen_rtx_USE (VOIDmode, slot),
4022 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4023 gen_rtx_CLOBBER (VOIDmode,
4028 val = force_operand (XEXP (slot, 0), NULL_RTX);
4031 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4032 argvec[count].mode = mode;
4033 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4034 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4037 argvec[count].partial
4038 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4040 if (argvec[count].reg == 0
4041 || argvec[count].partial != 0
4042 || reg_parm_stack_space > 0)
4044 locate_and_pad_parm (mode, NULL_TREE,
4045 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4048 argvec[count].reg != 0,
4050 reg_parm_stack_space, argvec[count].partial,
4051 NULL_TREE, &args_size, &argvec[count].locate);
4052 args_size.constant += argvec[count].locate.size.constant;
4053 gcc_assert (!argvec[count].locate.size.var);
4055 #ifdef BLOCK_REG_PADDING
4057 /* The argument is passed entirely in registers. See at which
4058 end it should be padded. */
4059 argvec[count].locate.where_pad =
4060 BLOCK_REG_PADDING (mode, NULL_TREE,
4061 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
4064 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4067 /* If this machine requires an external definition for library
4068 functions, write one out. */
4069 assemble_external_libcall (fun);
4071 original_args_size = args_size;
4072 args_size.constant = (((args_size.constant
4073 + stack_pointer_delta
4077 - stack_pointer_delta);
4079 args_size.constant = MAX (args_size.constant,
4080 reg_parm_stack_space);
4082 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4083 args_size.constant -= reg_parm_stack_space;
4085 if (args_size.constant > crtl->outgoing_args_size)
4086 crtl->outgoing_args_size = args_size.constant;
4088 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4090 int pushed = args_size.constant + pending_stack_adjust;
4091 if (pushed > current_function_pushed_stack_size)
4092 current_function_pushed_stack_size = pushed;
4095 if (ACCUMULATE_OUTGOING_ARGS)
4097 /* Since the stack pointer will never be pushed, it is possible for
4098 the evaluation of a parm to clobber something we have already
4099 written to the stack. Since most function calls on RISC machines
4100 do not use the stack, this is uncommon, but must work correctly.
4102 Therefore, we save any area of the stack that was already written
4103 and that we are using. Here we set up to do this by making a new
4104 stack usage map from the old one.
4106 Another approach might be to try to reorder the argument
4107 evaluations to avoid this conflicting stack usage. */
4109 needed = args_size.constant;
4111 /* Since we will be writing into the entire argument area, the
4112 map must be allocated for its entire size, not just the part that
4113 is the responsibility of the caller. */
4114 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4115 needed += reg_parm_stack_space;
4117 if (ARGS_GROW_DOWNWARD)
4118 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4121 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use, needed);
4123 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
4124 stack_usage_map = stack_usage_map_buf;
4126 if (initial_highest_arg_in_use)
4127 memcpy (stack_usage_map, initial_stack_usage_map,
4128 initial_highest_arg_in_use);
4130 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4131 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4132 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4135 /* We must be careful to use virtual regs before they're instantiated,
4136 and real regs afterwards. Loop optimization, for example, can create
4137 new libcalls after we've instantiated the virtual regs, and if we
4138 use virtuals anyway, they won't match the rtl patterns. */
4140 if (virtuals_instantiated)
4141 argblock = plus_constant (Pmode, stack_pointer_rtx,
4142 STACK_POINTER_OFFSET);
4144 argblock = virtual_outgoing_args_rtx;
4149 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4152 /* We push args individually in reverse order, perform stack alignment
4153 before the first push (the last arg). */
4155 anti_adjust_stack (GEN_INT (args_size.constant
4156 - original_args_size.constant));
4160 #ifdef REG_PARM_STACK_SPACE
4161 if (ACCUMULATE_OUTGOING_ARGS)
4163 /* The argument list is the property of the called routine and it
4164 may clobber it. If the fixed area has been used for previous
4165 parameters, we must save and restore it. */
4166 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4167 &low_to_save, &high_to_save);
4171 /* When expanding a normal call, args are stored in push order,
4172 which is the reverse of what we have here. */
4173 bool any_regs = false;
4174 for (int i = nargs; i-- > 0; )
4175 if (argvec[i].reg != NULL_RTX)
4177 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
4181 targetm.calls.call_args (pc_rtx, NULL_TREE);
4183 /* Push the args that need to be pushed. */
4185 have_push_fusage = false;
4187 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4188 are to be pushed. */
4189 for (count = 0; count < nargs; count++, argnum--)
4191 machine_mode mode = argvec[argnum].mode;
4192 rtx val = argvec[argnum].value;
4193 rtx reg = argvec[argnum].reg;
4194 int partial = argvec[argnum].partial;
4195 unsigned int parm_align = argvec[argnum].locate.boundary;
4196 int lower_bound = 0, upper_bound = 0, i;
4198 if (! (reg != 0 && partial == 0))
4202 if (ACCUMULATE_OUTGOING_ARGS)
4204 /* If this is being stored into a pre-allocated, fixed-size,
4205 stack area, save any previous data at that location. */
4207 if (ARGS_GROW_DOWNWARD)
4209 /* stack_slot is negative, but we want to index stack_usage_map
4210 with positive values. */
4211 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
4212 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4216 lower_bound = argvec[argnum].locate.slot_offset.constant;
4217 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4221 /* Don't worry about things in the fixed argument area;
4222 it has already been saved. */
4223 if (i < reg_parm_stack_space)
4224 i = reg_parm_stack_space;
4225 while (i < upper_bound && stack_usage_map[i] == 0)
4228 if (i < upper_bound)
4230 /* We need to make a save area. */
4232 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4233 machine_mode save_mode
4234 = mode_for_size (size, MODE_INT, 1);
4236 = plus_constant (Pmode, argblock,
4237 argvec[argnum].locate.offset.constant);
4239 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4241 if (save_mode == BLKmode)
4243 argvec[argnum].save_area
4244 = assign_stack_temp (BLKmode,
4245 argvec[argnum].locate.size.constant
4248 emit_block_move (validize_mem
4249 (copy_rtx (argvec[argnum].save_area)),
4251 GEN_INT (argvec[argnum].locate.size.constant),
4252 BLOCK_OP_CALL_PARM);
4256 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4258 emit_move_insn (argvec[argnum].save_area, stack_area);
4263 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4264 partial, reg, 0, argblock,
4265 GEN_INT (argvec[argnum].locate.offset.constant),
4266 reg_parm_stack_space,
4267 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
4269 /* Now mark the segment we just used. */
4270 if (ACCUMULATE_OUTGOING_ARGS)
4271 for (i = lower_bound; i < upper_bound; i++)
4272 stack_usage_map[i] = 1;
4276 /* Indicate argument access so that alias.c knows that these
4279 use = plus_constant (Pmode, argblock,
4280 argvec[argnum].locate.offset.constant);
4281 else if (have_push_fusage)
4285 /* When arguments are pushed, trying to tell alias.c where
4286 exactly this argument is won't work, because the
4287 auto-increment causes confusion. So we merely indicate
4288 that we access something with a known mode somewhere on
4290 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
4291 gen_rtx_SCRATCH (Pmode));
4292 have_push_fusage = true;
4294 use = gen_rtx_MEM (argvec[argnum].mode, use);
4295 use = gen_rtx_USE (VOIDmode, use);
4296 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4302 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4304 /* Now load any reg parms into their regs. */
4306 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4307 are to be pushed. */
4308 for (count = 0; count < nargs; count++, argnum--)
4310 machine_mode mode = argvec[argnum].mode;
4311 rtx val = argvec[argnum].value;
4312 rtx reg = argvec[argnum].reg;
4313 int partial = argvec[argnum].partial;
4314 #ifdef BLOCK_REG_PADDING
4318 /* Handle calls that pass values in multiple non-contiguous
4319 locations. The PA64 has examples of this for library calls. */
4320 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4321 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4322 else if (reg != 0 && partial == 0)
4324 emit_move_insn (reg, val);
4325 #ifdef BLOCK_REG_PADDING
4326 size = GET_MODE_SIZE (argvec[argnum].mode);
4328 /* Copied from load_register_parameters. */
4330 /* Handle case where we have a value that needs shifting
4331 up to the msb. eg. a QImode value and we're padding
4332 upward on a BYTES_BIG_ENDIAN machine. */
4333 if (size < UNITS_PER_WORD
4334 && (argvec[argnum].locate.where_pad
4335 == (BYTES_BIG_ENDIAN ? upward : downward)))
4338 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4340 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4341 report the whole reg as used. Strictly speaking, the
4342 call only uses SIZE bytes at the msb end, but it doesn't
4343 seem worth generating rtl to say that. */
4344 reg = gen_rtx_REG (word_mode, REGNO (reg));
4345 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4347 emit_move_insn (reg, x);
4355 /* Any regs containing parms remain in use through the call. */
4356 for (count = 0; count < nargs; count++)
4358 rtx reg = argvec[count].reg;
4359 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4360 use_group_regs (&call_fusage, reg);
4363 int partial = argvec[count].partial;
4367 gcc_assert (partial % UNITS_PER_WORD == 0);
4368 nregs = partial / UNITS_PER_WORD;
4369 use_regs (&call_fusage, REGNO (reg), nregs);
4372 use_reg (&call_fusage, reg);
4376 /* Pass the function the address in which to return a structure value. */
4377 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4379 emit_move_insn (struct_value,
4381 force_operand (XEXP (mem_value, 0),
4383 if (REG_P (struct_value))
4384 use_reg (&call_fusage, struct_value);
4387 /* Don't allow popping to be deferred, since then
4388 cse'ing of library calls could delete a call and leave the pop. */
4390 valreg = (mem_value == 0 && outmode != VOIDmode
4391 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4393 /* Stack must be properly aligned now. */
4394 gcc_assert (!(stack_pointer_delta
4395 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4397 before_call = get_last_insn ();
4399 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4400 will set inhibit_defer_pop to that value. */
4401 /* The return type is needed to decide how many bytes the function pops.
4402 Signedness plays no role in that, so for simplicity, we pretend it's
4403 always signed. We also assume that the list of arguments passed has
4404 no impact, so we pretend it is unknown. */
4406 emit_call_1 (fun, NULL,
4407 get_identifier (XSTR (orgfun, 0)),
4408 build_function_type (tfom, NULL_TREE),
4409 original_args_size.constant, args_size.constant,
4411 targetm.calls.function_arg (args_so_far,
4412 VOIDmode, void_type_node, true),
4414 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4419 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
4420 rtx_call_insn *last = last_call_insn ();
4421 add_reg_note (last, REG_CALL_DECL, datum);
4424 /* Right-shift returned value if necessary. */
4425 if (!pcc_struct_value
4426 && TYPE_MODE (tfom) != BLKmode
4427 && targetm.calls.return_in_msb (tfom))
4429 shift_return_value (TYPE_MODE (tfom), false, valreg);
4430 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
4433 targetm.calls.end_call_args ();
4435 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
4436 that it should complain if nonvolatile values are live. For
4437 functions that cannot return, inform flow that control does not
4439 if (flags & ECF_NORETURN)
4441 /* The barrier note must be emitted
4442 immediately after the CALL_INSN. Some ports emit more than
4443 just a CALL_INSN above, so we must search for it here. */
4444 rtx_insn *last = get_last_insn ();
4445 while (!CALL_P (last))
4447 last = PREV_INSN (last);
4448 /* There was no CALL_INSN? */
4449 gcc_assert (last != before_call);
4452 emit_barrier_after (last);
4455 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
4456 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
4457 if (flags & ECF_NOTHROW)
4459 rtx_insn *last = get_last_insn ();
4460 while (!CALL_P (last))
4462 last = PREV_INSN (last);
4463 /* There was no CALL_INSN? */
4464 gcc_assert (last != before_call);
4467 make_reg_eh_region_note_nothrow_nononlocal (last);
4470 /* Now restore inhibit_defer_pop to its actual original value. */
4475 /* Copy the value to the right place. */
4476 if (outmode != VOIDmode && retval)
4482 if (value != mem_value)
4483 emit_move_insn (value, mem_value);
4485 else if (GET_CODE (valreg) == PARALLEL)
4488 value = gen_reg_rtx (outmode);
4489 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4493 /* Convert to the proper mode if a promotion has been active. */
4494 if (GET_MODE (valreg) != outmode)
4496 int unsignedp = TYPE_UNSIGNED (tfom);
4498 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
4499 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
4500 == GET_MODE (valreg));
4501 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
4505 emit_move_insn (value, valreg);
4511 if (ACCUMULATE_OUTGOING_ARGS)
4513 #ifdef REG_PARM_STACK_SPACE
4515 restore_fixed_argument_area (save_area, argblock,
4516 high_to_save, low_to_save);
4519 /* If we saved any argument areas, restore them. */
4520 for (count = 0; count < nargs; count++)
4521 if (argvec[count].save_area)
4523 machine_mode save_mode = GET_MODE (argvec[count].save_area);
4524 rtx adr = plus_constant (Pmode, argblock,
4525 argvec[count].locate.offset.constant);
4526 rtx stack_area = gen_rtx_MEM (save_mode,
4527 memory_address (save_mode, adr));
4529 if (save_mode == BLKmode)
4530 emit_block_move (stack_area,
4532 (copy_rtx (argvec[count].save_area)),
4533 GEN_INT (argvec[count].locate.size.constant),
4534 BLOCK_OP_CALL_PARM);
4536 emit_move_insn (stack_area, argvec[count].save_area);
4539 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4540 stack_usage_map = initial_stack_usage_map;
4543 free (stack_usage_map_buf);
4549 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4550 (emitting the queue unless NO_QUEUE is nonzero),
4551 for a value of mode OUTMODE,
4552 with NARGS different arguments, passed as alternating rtx values
4553 and machine_modes to convert them to.
4555 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4556 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
4557 other types of library calls. */
4560 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4561 machine_mode outmode, int nargs, ...)
4565 va_start (p, nargs);
4566 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4570 /* Like emit_library_call except that an extra argument, VALUE,
4571 comes second and says where to store the result.
4572 (If VALUE is zero, this function chooses a convenient way
4573 to return the value.
4575 This function returns an rtx for where the value is to be found.
4576 If VALUE is nonzero, VALUE is returned. */
4579 emit_library_call_value (rtx orgfun, rtx value,
4580 enum libcall_type fn_type,
4581 machine_mode outmode, int nargs, ...)
4586 va_start (p, nargs);
4587 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4595 /* Store pointer bounds argument ARG into Bounds Table entry
4596 associated with PARM. */
4598 store_bounds (struct arg_data *arg, struct arg_data *parm)
4600 rtx slot = NULL, ptr = NULL, addr = NULL;
4602 /* We may pass bounds not associated with any pointer. */
4605 gcc_assert (arg->special_slot);
4606 slot = arg->special_slot;
4609 /* Find pointer associated with bounds and where it is
4615 gcc_assert (!arg->special_slot);
4617 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
4619 else if (REG_P (parm->reg))
4621 gcc_assert (arg->special_slot);
4622 slot = arg->special_slot;
4624 if (MEM_P (parm->value))
4625 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
4626 else if (REG_P (parm->value))
4627 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
4630 gcc_assert (!arg->pointer_offset);
4636 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
4638 gcc_assert (arg->special_slot);
4639 slot = arg->special_slot;
4641 if (parm->parallel_value)
4642 ptr = chkp_get_value_with_offs (parm->parallel_value,
4643 GEN_INT (arg->pointer_offset));
4649 /* Expand bounds. */
4651 arg->value = expand_normal (arg->tree_value);
4653 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
4656 /* Store a single argument for a function call
4657 into the register or memory area where it must be passed.
4658 *ARG describes the argument value and where to pass it.
4660 ARGBLOCK is the address of the stack-block for all the arguments,
4661 or 0 on a machine where arguments are pushed individually.
4663 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4664 so must be careful about how the stack is used.
4666 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4667 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4668 that we need not worry about saving and restoring the stack.
4670 FNDECL is the declaration of the function we are calling.
4672 Return nonzero if this arg should cause sibcall failure,
4676 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4677 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4679 tree pval = arg->tree_value;
4683 int i, lower_bound = 0, upper_bound = 0;
4684 int sibcall_failure = 0;
4686 if (TREE_CODE (pval) == ERROR_MARK)
4689 /* Push a new temporary level for any temporaries we make for
4693 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4695 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4696 save any previous data at that location. */
4697 if (argblock && ! variable_size && arg->stack)
4699 if (ARGS_GROW_DOWNWARD)
4701 /* stack_slot is negative, but we want to index stack_usage_map
4702 with positive values. */
4703 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4704 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4708 lower_bound = upper_bound - arg->locate.size.constant;
4712 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4713 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4717 upper_bound = lower_bound + arg->locate.size.constant;
4721 /* Don't worry about things in the fixed argument area;
4722 it has already been saved. */
4723 if (i < reg_parm_stack_space)
4724 i = reg_parm_stack_space;
4725 while (i < upper_bound && stack_usage_map[i] == 0)
4728 if (i < upper_bound)
4730 /* We need to make a save area. */
4731 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4732 machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4733 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4734 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4736 if (save_mode == BLKmode)
4739 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
4740 preserve_temp_slots (arg->save_area);
4741 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
4743 GEN_INT (arg->locate.size.constant),
4744 BLOCK_OP_CALL_PARM);
4748 arg->save_area = gen_reg_rtx (save_mode);
4749 emit_move_insn (arg->save_area, stack_area);
4755 /* If this isn't going to be placed on both the stack and in registers,
4756 set up the register and number of words. */
4757 if (! arg->pass_on_stack)
4759 if (flags & ECF_SIBCALL)
4760 reg = arg->tail_call_reg;
4763 partial = arg->partial;
4766 /* Being passed entirely in a register. We shouldn't be called in
4768 gcc_assert (reg == 0 || partial != 0);
4770 /* If this arg needs special alignment, don't load the registers
4772 if (arg->n_aligned_regs != 0)
4775 /* If this is being passed partially in a register, we can't evaluate
4776 it directly into its stack slot. Otherwise, we can. */
4777 if (arg->value == 0)
4779 /* stack_arg_under_construction is nonzero if a function argument is
4780 being evaluated directly into the outgoing argument list and
4781 expand_call must take special action to preserve the argument list
4782 if it is called recursively.
4784 For scalar function arguments stack_usage_map is sufficient to
4785 determine which stack slots must be saved and restored. Scalar
4786 arguments in general have pass_on_stack == 0.
4788 If this argument is initialized by a function which takes the
4789 address of the argument (a C++ constructor or a C function
4790 returning a BLKmode structure), then stack_usage_map is
4791 insufficient and expand_call must push the stack around the
4792 function call. Such arguments have pass_on_stack == 1.
4794 Note that it is always safe to set stack_arg_under_construction,
4795 but this generates suboptimal code if set when not needed. */
4797 if (arg->pass_on_stack)
4798 stack_arg_under_construction++;
4800 arg->value = expand_expr (pval,
4802 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4803 ? NULL_RTX : arg->stack,
4804 VOIDmode, EXPAND_STACK_PARM);
4806 /* If we are promoting object (or for any other reason) the mode
4807 doesn't agree, convert the mode. */
4809 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4810 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4811 arg->value, arg->unsignedp);
4813 if (arg->pass_on_stack)
4814 stack_arg_under_construction--;
4817 /* Check for overlap with already clobbered argument area. */
4818 if ((flags & ECF_SIBCALL)
4819 && MEM_P (arg->value)
4820 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4821 arg->locate.size.constant))
4822 sibcall_failure = 1;
4824 /* Don't allow anything left on stack from computation
4825 of argument to alloca. */
4826 if (flags & ECF_MAY_BE_ALLOCA)
4827 do_pending_stack_adjust ();
4829 if (arg->value == arg->stack)
4830 /* If the value is already in the stack slot, we are done. */
4832 else if (arg->mode != BLKmode)
4835 unsigned int parm_align;
4837 /* Argument is a scalar, not entirely passed in registers.
4838 (If part is passed in registers, arg->partial says how much
4839 and emit_push_insn will take care of putting it there.)
4841 Push it, and if its size is less than the
4842 amount of space allocated to it,
4843 also bump stack pointer by the additional space.
4844 Note that in C the default argument promotions
4845 will prevent such mismatches. */
4847 size = GET_MODE_SIZE (arg->mode);
4848 /* Compute how much space the push instruction will push.
4849 On many machines, pushing a byte will advance the stack
4850 pointer by a halfword. */
4851 #ifdef PUSH_ROUNDING
4852 size = PUSH_ROUNDING (size);
4856 /* Compute how much space the argument should get:
4857 round up to a multiple of the alignment for arguments. */
4858 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4859 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4860 / (PARM_BOUNDARY / BITS_PER_UNIT))
4861 * (PARM_BOUNDARY / BITS_PER_UNIT));
4863 /* Compute the alignment of the pushed argument. */
4864 parm_align = arg->locate.boundary;
4865 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4867 int pad = used - size;
4870 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4871 parm_align = MIN (parm_align, pad_align);
4875 /* This isn't already where we want it on the stack, so put it there.
4876 This can either be done with push or copy insns. */
4877 if (!emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4878 parm_align, partial, reg, used - size, argblock,
4879 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4880 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
4881 sibcall_failure = 1;
4883 /* Unless this is a partially-in-register argument, the argument is now
4886 arg->value = arg->stack;
4890 /* BLKmode, at least partly to be pushed. */
4892 unsigned int parm_align;
4896 /* Pushing a nonscalar.
4897 If part is passed in registers, PARTIAL says how much
4898 and emit_push_insn will take care of putting it there. */
4900 /* Round its size up to a multiple
4901 of the allocation unit for arguments. */
4903 if (arg->locate.size.var != 0)
4906 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4910 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4911 for BLKmode is careful to avoid it. */
4912 excess = (arg->locate.size.constant
4913 - int_size_in_bytes (TREE_TYPE (pval))
4915 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4916 NULL_RTX, TYPE_MODE (sizetype),
4920 parm_align = arg->locate.boundary;
4922 /* When an argument is padded down, the block is aligned to
4923 PARM_BOUNDARY, but the actual argument isn't. */
4924 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4926 if (arg->locate.size.var)
4927 parm_align = BITS_PER_UNIT;
4930 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4931 parm_align = MIN (parm_align, excess_align);
4935 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4937 /* emit_push_insn might not work properly if arg->value and
4938 argblock + arg->locate.offset areas overlap. */
4942 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4943 || (GET_CODE (XEXP (x, 0)) == PLUS
4944 && XEXP (XEXP (x, 0), 0) ==
4945 crtl->args.internal_arg_pointer
4946 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
4948 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
4949 i = INTVAL (XEXP (XEXP (x, 0), 1));
4951 /* expand_call should ensure this. */
4952 gcc_assert (!arg->locate.offset.var
4953 && arg->locate.size.var == 0
4954 && CONST_INT_P (size_rtx));
4956 if (arg->locate.offset.constant > i)
4958 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4959 sibcall_failure = 1;
4961 else if (arg->locate.offset.constant < i)
4963 /* Use arg->locate.size.constant instead of size_rtx
4964 because we only care about the part of the argument
4966 if (i < (arg->locate.offset.constant
4967 + arg->locate.size.constant))
4968 sibcall_failure = 1;
4972 /* Even though they appear to be at the same location,
4973 if part of the outgoing argument is in registers,
4974 they aren't really at the same location. Check for
4975 this by making sure that the incoming size is the
4976 same as the outgoing size. */
4977 if (arg->locate.size.constant != INTVAL (size_rtx))
4978 sibcall_failure = 1;
4983 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4984 parm_align, partial, reg, excess, argblock,
4985 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4986 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
4988 /* Unless this is a partially-in-register argument, the argument is now
4991 ??? Unlike the case above, in which we want the actual
4992 address of the data, so that we can load it directly into a
4993 register, here we want the address of the stack slot, so that
4994 it's properly aligned for word-by-word copying or something
4995 like that. It's not clear that this is always correct. */
4997 arg->value = arg->stack_slot;
5000 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5002 tree type = TREE_TYPE (arg->tree_value);
5004 = emit_group_load_into_temps (arg->reg, arg->value, type,
5005 int_size_in_bytes (type));
5008 /* Mark all slots this store used. */
5009 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5010 && argblock && ! variable_size && arg->stack)
5011 for (i = lower_bound; i < upper_bound; i++)
5012 stack_usage_map[i] = 1;
5014 /* Once we have pushed something, pops can't safely
5015 be deferred during the rest of the arguments. */
5018 /* Free any temporary slots made in processing this argument. */
5021 return sibcall_failure;
5024 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5027 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5033 /* If the type has variable size... */
5034 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5037 /* If the type is marked as addressable (it is required
5038 to be constructed into the stack)... */
5039 if (TREE_ADDRESSABLE (type))
5045 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5046 takes trailing padding of a structure into account. */
5047 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5050 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5055 /* If the type has variable size... */
5056 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5059 /* If the type is marked as addressable (it is required
5060 to be constructed into the stack)... */
5061 if (TREE_ADDRESSABLE (type))
5064 /* If the padding and mode of the type is such that a copy into
5065 a register would put it into the wrong part of the register. */
5067 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5068 && (FUNCTION_ARG_PADDING (mode, type)
5069 == (BYTES_BIG_ENDIAN ? upward : downward)))