1 /* Target-dependent code for PowerPC systems using the SVR4 ABI
2 for GDB, the GNU debugger.
4 Copyright (C) 2000, 2001, 2002, 2003, 2005, 2007
5 Free Software Foundation, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "gdb_string.h"
28 #include "gdb_assert.h"
34 /* Pass the arguments in either registers, or in the stack. Using the
35 ppc sysv ABI, the first eight words of the argument list (that might
36 be less than eight parameters if some parameters occupy more than one
37 word) are passed in r3..r10 registers. float and double parameters are
38 passed in fpr's, in addition to that. Rest of the parameters if any
39 are passed in user stack.
41 If the function is returning a structure, then the return address is passed
42 in r3, then the first 7 words of the parametes can be passed in registers,
46 ppc_sysv_abi_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
47 struct regcache *regcache, CORE_ADDR bp_addr,
48 int nargs, struct value **args, CORE_ADDR sp,
49 int struct_return, CORE_ADDR struct_addr)
51 struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
53 int argspace = 0; /* 0 is an initial wrong guess. */
56 regcache_cooked_read_unsigned (regcache,
57 gdbarch_sp_regnum (current_gdbarch),
60 /* Go through the argument list twice.
62 Pass 1: Figure out how much new stack space is required for
63 arguments and pushed values. Unlike the PowerOpen ABI, the SysV
64 ABI doesn't reserve any extra space for parameters which are put
65 in registers, but does always push structures and then pass their
68 Pass 2: Replay the same computation but this time also write the
69 values out to the target. */
71 for (write_pass = 0; write_pass < 2; write_pass++)
74 /* Next available floating point register for float and double
77 /* Next available general register for non-float, non-vector
80 /* Next available vector register for vector arguments. */
82 /* Arguments start above the "LR save word" and "Back chain". */
83 int argoffset = 2 * tdep->wordsize;
84 /* Structures start after the arguments. */
85 int structoffset = argoffset + argspace;
87 /* If the function is returning a `struct', then the first word
88 (which will be passed in r3) is used for struct return
89 address. In that case we should advance one word and start
90 from r4 register to copy parameters. */
94 regcache_cooked_write_signed (regcache,
95 tdep->ppc_gp0_regnum + greg,
100 for (argno = 0; argno < nargs; argno++)
102 struct value *arg = args[argno];
103 struct type *type = check_typedef (value_type (arg));
104 int len = TYPE_LENGTH (type);
105 const bfd_byte *val = value_contents (arg);
107 if (TYPE_CODE (type) == TYPE_CODE_FLT
108 && ppc_floating_point_unit_p (current_gdbarch) && len <= 8)
110 /* Floating point value converted to "double" then
111 passed in an FP register, when the registers run out,
112 8 byte aligned stack is used. */
117 /* Always store the floating point value using
118 the register's floating-point format. */
119 gdb_byte regval[MAX_REGISTER_SIZE];
121 = register_type (gdbarch, tdep->ppc_fp0_regnum + freg);
122 convert_typed_floating (val, type, regval, regtype);
123 regcache_cooked_write (regcache,
124 tdep->ppc_fp0_regnum + freg,
131 /* SysV ABI converts floats to doubles before
132 writing them to an 8 byte aligned stack location. */
133 argoffset = align_up (argoffset, 8);
137 convert_typed_floating (val, type, memval,
138 builtin_type_ieee_double);
139 write_memory (sp + argoffset, val, len);
144 else if (len == 8 && (TYPE_CODE (type) == TYPE_CODE_INT /* long long */
145 || (!ppc_floating_point_unit_p (current_gdbarch) && TYPE_CODE (type) == TYPE_CODE_FLT))) /* double */
147 /* "long long" or "double" passed in an odd/even
148 register pair with the low addressed word in the odd
149 register and the high addressed word in the even
150 register, or when the registers run out an 8 byte
151 aligned stack location. */
154 /* Just in case GREG was 10. */
156 argoffset = align_up (argoffset, 8);
158 write_memory (sp + argoffset, val, len);
161 else if (tdep->wordsize == 8)
164 regcache_cooked_write (regcache,
165 tdep->ppc_gp0_regnum + greg, val);
170 /* Must start on an odd register - r3/r4 etc. */
175 regcache_cooked_write (regcache,
176 tdep->ppc_gp0_regnum + greg + 0,
178 regcache_cooked_write (regcache,
179 tdep->ppc_gp0_regnum + greg + 1,
186 && TYPE_CODE (type) == TYPE_CODE_ARRAY
187 && TYPE_VECTOR (type) && tdep->ppc_vr0_regnum >= 0)
189 /* Vector parameter passed in an Altivec register, or
190 when that runs out, 16 byte aligned stack location. */
194 regcache_cooked_write (regcache,
195 tdep->ppc_vr0_regnum + vreg, val);
200 argoffset = align_up (argoffset, 16);
202 write_memory (sp + argoffset, val, 16);
207 && TYPE_CODE (type) == TYPE_CODE_ARRAY
208 && TYPE_VECTOR (type) && tdep->ppc_ev0_regnum >= 0)
210 /* Vector parameter passed in an e500 register, or when
211 that runs out, 8 byte aligned stack location. Note
212 that since e500 vector and general purpose registers
213 both map onto the same underlying register set, a
214 "greg" and not a "vreg" is consumed here. A cooked
215 write stores the value in the correct locations
216 within the raw register cache. */
220 regcache_cooked_write (regcache,
221 tdep->ppc_ev0_regnum + greg, val);
226 argoffset = align_up (argoffset, 8);
228 write_memory (sp + argoffset, val, 8);
234 /* Reduce the parameter down to something that fits in a
236 gdb_byte word[MAX_REGISTER_SIZE];
237 memset (word, 0, MAX_REGISTER_SIZE);
238 if (len > tdep->wordsize
239 || TYPE_CODE (type) == TYPE_CODE_STRUCT
240 || TYPE_CODE (type) == TYPE_CODE_UNION)
242 /* Structs and large values are put on an 8 byte
244 structoffset = align_up (structoffset, 8);
246 write_memory (sp + structoffset, val, len);
247 /* ... and then a "word" pointing to that address is
248 passed as the parameter. */
249 store_unsigned_integer (word, tdep->wordsize,
253 else if (TYPE_CODE (type) == TYPE_CODE_INT)
254 /* Sign or zero extend the "int" into a "word". */
255 store_unsigned_integer (word, tdep->wordsize,
256 unpack_long (type, val));
258 /* Always goes in the low address. */
259 memcpy (word, val, len);
260 /* Store that "word" in a register, or on the stack.
261 The words have "4" byte alignment. */
265 regcache_cooked_write (regcache,
266 tdep->ppc_gp0_regnum + greg, word);
271 argoffset = align_up (argoffset, tdep->wordsize);
273 write_memory (sp + argoffset, word, tdep->wordsize);
274 argoffset += tdep->wordsize;
279 /* Compute the actual stack space requirements. */
282 /* Remember the amount of space needed by the arguments. */
283 argspace = argoffset;
284 /* Allocate space for both the arguments and the structures. */
285 sp -= (argoffset + structoffset);
286 /* Ensure that the stack is still 16 byte aligned. */
287 sp = align_down (sp, 16);
290 /* The psABI says that "A caller of a function that takes a
291 variable argument list shall set condition register bit 6 to
292 1 if it passes one or more arguments in the floating-point
293 registers. It is strongly recommended that the caller set the
294 bit to 0 otherwise..." Doing this for normal functions too
300 regcache_cooked_read_unsigned (regcache, tdep->ppc_cr_regnum, &cr);
305 regcache_cooked_write_unsigned (regcache, tdep->ppc_cr_regnum, cr);
310 regcache_cooked_write_signed (regcache,
311 gdbarch_sp_regnum (current_gdbarch), sp);
313 /* Write the backchain (it occupies WORDSIZED bytes). */
314 write_memory_signed_integer (sp, tdep->wordsize, saved_sp);
316 /* Point the inferior function call's return address at the dummy's
318 regcache_cooked_write_signed (regcache, tdep->ppc_lr_regnum, bp_addr);
323 /* Handle the return-value conventions specified by the SysV 32-bit
324 PowerPC ABI (including all the supplements):
326 no floating-point: floating-point values returned using 32-bit
327 general-purpose registers.
329 Altivec: 128-bit vectors returned using vector registers.
331 e500: 64-bit vectors returned using the full full 64 bit EV
332 register, floating-point values returned using 32-bit
333 general-purpose registers.
335 GCC (broken): Small struct values right (instead of left) aligned
336 when returned in general-purpose registers. */
338 static enum return_value_convention
339 do_ppc_sysv_return_value (struct gdbarch *gdbarch, struct type *type,
340 struct regcache *regcache, void *readbuf,
341 const void *writebuf, int broken_gcc)
343 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
344 gdb_assert (tdep->wordsize == 4);
345 if (TYPE_CODE (type) == TYPE_CODE_FLT
346 && TYPE_LENGTH (type) <= 8
347 && ppc_floating_point_unit_p (gdbarch))
351 /* Floats and doubles stored in "f1". Convert the value to
352 the required type. */
353 gdb_byte regval[MAX_REGISTER_SIZE];
354 struct type *regtype = register_type (gdbarch,
355 tdep->ppc_fp0_regnum + 1);
356 regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1, regval);
357 convert_typed_floating (regval, regtype, readbuf, type);
361 /* Floats and doubles stored in "f1". Convert the value to
362 the register's "double" type. */
363 gdb_byte regval[MAX_REGISTER_SIZE];
364 struct type *regtype = register_type (gdbarch, tdep->ppc_fp0_regnum);
365 convert_typed_floating (writebuf, type, regval, regtype);
366 regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1, regval);
368 return RETURN_VALUE_REGISTER_CONVENTION;
370 if ((TYPE_CODE (type) == TYPE_CODE_INT && TYPE_LENGTH (type) == 8)
371 || (TYPE_CODE (type) == TYPE_CODE_FLT && TYPE_LENGTH (type) == 8))
375 /* A long long, or a double stored in the 32 bit r3/r4. */
376 regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 3,
377 (bfd_byte *) readbuf + 0);
378 regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 4,
379 (bfd_byte *) readbuf + 4);
383 /* A long long, or a double stored in the 32 bit r3/r4. */
384 regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3,
385 (const bfd_byte *) writebuf + 0);
386 regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 4,
387 (const bfd_byte *) writebuf + 4);
389 return RETURN_VALUE_REGISTER_CONVENTION;
391 if (TYPE_CODE (type) == TYPE_CODE_INT
392 && TYPE_LENGTH (type) <= tdep->wordsize)
396 /* Some sort of integer stored in r3. Since TYPE isn't
397 bigger than the register, sign extension isn't a problem
398 - just do everything unsigned. */
400 regcache_cooked_read_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
402 store_unsigned_integer (readbuf, TYPE_LENGTH (type), regval);
406 /* Some sort of integer stored in r3. Use unpack_long since
407 that should handle any required sign extension. */
408 regcache_cooked_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
409 unpack_long (type, writebuf));
411 return RETURN_VALUE_REGISTER_CONVENTION;
413 if (TYPE_LENGTH (type) == 16
414 && TYPE_CODE (type) == TYPE_CODE_ARRAY
415 && TYPE_VECTOR (type) && tdep->ppc_vr0_regnum >= 0)
419 /* Altivec places the return value in "v2". */
420 regcache_cooked_read (regcache, tdep->ppc_vr0_regnum + 2, readbuf);
424 /* Altivec places the return value in "v2". */
425 regcache_cooked_write (regcache, tdep->ppc_vr0_regnum + 2, writebuf);
427 return RETURN_VALUE_REGISTER_CONVENTION;
429 if (TYPE_LENGTH (type) == 8
430 && TYPE_CODE (type) == TYPE_CODE_ARRAY
431 && TYPE_VECTOR (type) && tdep->ppc_ev0_regnum >= 0)
433 /* The e500 ABI places return values for the 64-bit DSP types
434 (__ev64_opaque__) in r3. However, in GDB-speak, ev3
435 corresponds to the entire r3 value for e500, whereas GDB's r3
436 only corresponds to the least significant 32-bits. So place
437 the 64-bit DSP type's value in ev3. */
439 regcache_cooked_read (regcache, tdep->ppc_ev0_regnum + 3, readbuf);
441 regcache_cooked_write (regcache, tdep->ppc_ev0_regnum + 3, writebuf);
442 return RETURN_VALUE_REGISTER_CONVENTION;
444 if (broken_gcc && TYPE_LENGTH (type) <= 8)
446 /* GCC screwed up for structures or unions whose size is less
447 than or equal to 8 bytes.. Instead of left-aligning, it
448 right-aligns the data into the buffer formed by r3, r4. */
449 gdb_byte regvals[MAX_REGISTER_SIZE * 2];
450 int len = TYPE_LENGTH (type);
451 int offset = (2 * tdep->wordsize - len) % tdep->wordsize;
455 regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 3,
456 regvals + 0 * tdep->wordsize);
457 if (len > tdep->wordsize)
458 regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 4,
459 regvals + 1 * tdep->wordsize);
460 memcpy (readbuf, regvals + offset, len);
464 memset (regvals, 0, sizeof regvals);
465 memcpy (regvals + offset, writebuf, len);
466 regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3,
467 regvals + 0 * tdep->wordsize);
468 if (len > tdep->wordsize)
469 regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 4,
470 regvals + 1 * tdep->wordsize);
473 return RETURN_VALUE_REGISTER_CONVENTION;
475 if (TYPE_LENGTH (type) <= 8)
479 /* This matches SVr4 PPC, it does not match GCC. */
480 /* The value is right-padded to 8 bytes and then loaded, as
481 two "words", into r3/r4. */
482 gdb_byte regvals[MAX_REGISTER_SIZE * 2];
483 regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 3,
484 regvals + 0 * tdep->wordsize);
485 if (TYPE_LENGTH (type) > tdep->wordsize)
486 regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 4,
487 regvals + 1 * tdep->wordsize);
488 memcpy (readbuf, regvals, TYPE_LENGTH (type));
492 /* This matches SVr4 PPC, it does not match GCC. */
493 /* The value is padded out to 8 bytes and then loaded, as
494 two "words" into r3/r4. */
495 gdb_byte regvals[MAX_REGISTER_SIZE * 2];
496 memset (regvals, 0, sizeof regvals);
497 memcpy (regvals, writebuf, TYPE_LENGTH (type));
498 regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3,
499 regvals + 0 * tdep->wordsize);
500 if (TYPE_LENGTH (type) > tdep->wordsize)
501 regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 4,
502 regvals + 1 * tdep->wordsize);
504 return RETURN_VALUE_REGISTER_CONVENTION;
506 return RETURN_VALUE_STRUCT_CONVENTION;
509 enum return_value_convention
510 ppc_sysv_abi_return_value (struct gdbarch *gdbarch, struct type *valtype,
511 struct regcache *regcache, gdb_byte *readbuf,
512 const gdb_byte *writebuf)
514 return do_ppc_sysv_return_value (gdbarch, valtype, regcache, readbuf,
518 enum return_value_convention
519 ppc_sysv_abi_broken_return_value (struct gdbarch *gdbarch,
520 struct type *valtype,
521 struct regcache *regcache,
522 gdb_byte *readbuf, const gdb_byte *writebuf)
524 return do_ppc_sysv_return_value (gdbarch, valtype, regcache, readbuf,
528 /* The helper function for 64-bit SYSV push_dummy_call. Converts the
529 function's code address back into the function's descriptor
532 Find a value for the TOC register. Every symbol should have both
533 ".FN" and "FN" in the minimal symbol table. "FN" points at the
534 FN's descriptor, while ".FN" points at the entry point (which
535 matches FUNC_ADDR). Need to reverse from FUNC_ADDR back to the
536 FN's descriptor address (while at the same time being careful to
537 find "FN" in the same object file as ".FN"). */
540 convert_code_addr_to_desc_addr (CORE_ADDR code_addr, CORE_ADDR *desc_addr)
542 struct obj_section *dot_fn_section;
543 struct minimal_symbol *dot_fn;
544 struct minimal_symbol *fn;
546 /* Find the minimal symbol that corresponds to CODE_ADDR (should
547 have a name of the form ".FN"). */
548 dot_fn = lookup_minimal_symbol_by_pc (code_addr);
549 if (dot_fn == NULL || SYMBOL_LINKAGE_NAME (dot_fn)[0] != '.')
551 /* Get the section that contains CODE_ADDR. Need this for the
552 "objfile" that it contains. */
553 dot_fn_section = find_pc_section (code_addr);
554 if (dot_fn_section == NULL || dot_fn_section->objfile == NULL)
556 /* Now find the corresponding "FN" (dropping ".") minimal symbol's
557 address. Only look for the minimal symbol in ".FN"'s object file
558 - avoids problems when two object files (i.e., shared libraries)
559 contain a minimal symbol with the same name. */
560 fn = lookup_minimal_symbol (SYMBOL_LINKAGE_NAME (dot_fn) + 1, NULL,
561 dot_fn_section->objfile);
564 /* Found a descriptor. */
565 (*desc_addr) = SYMBOL_VALUE_ADDRESS (fn);
569 /* Pass the arguments in either registers, or in the stack. Using the
572 This implements a dumbed down version of the ABI. It always writes
573 values to memory, GPR and FPR, even when not necessary. Doing this
574 greatly simplifies the logic. */
577 ppc64_sysv_abi_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
578 struct regcache *regcache, CORE_ADDR bp_addr,
579 int nargs, struct value **args, CORE_ADDR sp,
580 int struct_return, CORE_ADDR struct_addr)
582 CORE_ADDR func_addr = find_function_addr (function, NULL);
583 struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
585 /* See for-loop comment below. */
587 /* Size of the Altivec's vector parameter region, the final value is
588 computed in the for-loop below. */
589 LONGEST vparam_size = 0;
590 /* Size of the general parameter region, the final value is computed
591 in the for-loop below. */
592 LONGEST gparam_size = 0;
593 /* Kevin writes ... I don't mind seeing tdep->wordsize used in the
594 calls to align_up(), align_down(), etc. because this makes it
595 easier to reuse this code (in a copy/paste sense) in the future,
596 but it is a 64-bit ABI and asserting that the wordsize is 8 bytes
597 at some point makes it easier to verify that this function is
598 correct without having to do a non-local analysis to figure out
599 the possible values of tdep->wordsize. */
600 gdb_assert (tdep->wordsize == 8);
602 /* By this stage in the proceedings, SP has been decremented by "red
603 zone size" + "struct return size". Fetch the stack-pointer from
604 before this and use that as the BACK_CHAIN. */
605 regcache_cooked_read_unsigned (regcache,
606 gdbarch_sp_regnum (current_gdbarch),
609 /* Go through the argument list twice.
611 Pass 1: Compute the function call's stack space and register
614 Pass 2: Replay the same computation but this time also write the
615 values out to the target. */
617 for (write_pass = 0; write_pass < 2; write_pass++)
620 /* Next available floating point register for float and double
623 /* Next available general register for non-vector (but possibly
626 /* Next available vector register for vector arguments. */
628 /* The address, at which the next general purpose parameter
629 (integer, struct, float, ...) should be saved. */
631 /* Address, at which the next Altivec vector parameter should be
637 /* During the first pass, GPARAM and VPARAM are more like
638 offsets (start address zero) than addresses. That way
639 the accumulate the total stack space each region
646 /* Decrement the stack pointer making space for the Altivec
647 and general on-stack parameters. Set vparam and gparam
648 to their corresponding regions. */
649 vparam = align_down (sp - vparam_size, 16);
650 gparam = align_down (vparam - gparam_size, 16);
651 /* Add in space for the TOC, link editor double word,
652 compiler double word, LR save area, CR save area. */
653 sp = align_down (gparam - 48, 16);
656 /* If the function is returning a `struct', then there is an
657 extra hidden parameter (which will be passed in r3)
658 containing the address of that struct.. In that case we
659 should advance one word and start from r4 register to copy
660 parameters. This also consumes one on-stack parameter slot. */
664 regcache_cooked_write_signed (regcache,
665 tdep->ppc_gp0_regnum + greg,
668 gparam = align_up (gparam + tdep->wordsize, tdep->wordsize);
671 for (argno = 0; argno < nargs; argno++)
673 struct value *arg = args[argno];
674 struct type *type = check_typedef (value_type (arg));
675 const bfd_byte *val = value_contents (arg);
676 if (TYPE_CODE (type) == TYPE_CODE_FLT && TYPE_LENGTH (type) <= 8)
678 /* Floats and Doubles go in f1 .. f13. They also
679 consume a left aligned GREG,, and can end up in
683 if (ppc_floating_point_unit_p (current_gdbarch)
686 gdb_byte regval[MAX_REGISTER_SIZE];
688 = register_type (gdbarch, tdep->ppc_fp0_regnum);
689 convert_typed_floating (val, type, regval, regtype);
690 regcache_cooked_write (regcache,
691 tdep->ppc_fp0_regnum + freg,
696 /* The ABI states "Single precision floating
697 point values are mapped to the first word in
698 a single doubleword" and "... floating point
699 values mapped to the first eight doublewords
700 of the parameter save area are also passed in
703 This code interprets that to mean: store it,
704 left aligned, in the general register. */
705 gdb_byte regval[MAX_REGISTER_SIZE];
706 memset (regval, 0, sizeof regval);
707 memcpy (regval, val, TYPE_LENGTH (type));
708 regcache_cooked_write (regcache,
709 tdep->ppc_gp0_regnum + greg,
712 write_memory (gparam, val, TYPE_LENGTH (type));
714 /* Always consume parameter stack space. */
717 gparam = align_up (gparam + TYPE_LENGTH (type), tdep->wordsize);
719 else if (TYPE_LENGTH (type) == 16 && TYPE_VECTOR (type)
720 && TYPE_CODE (type) == TYPE_CODE_ARRAY
721 && tdep->ppc_vr0_regnum >= 0)
723 /* In the Altivec ABI, vectors go in the vector
724 registers v2 .. v13, or when that runs out, a vector
725 annex which goes above all the normal parameters.
726 NOTE: cagney/2003-09-21: This is a guess based on the
727 PowerOpen Altivec ABI. */
731 regcache_cooked_write (regcache,
732 tdep->ppc_vr0_regnum + vreg, val);
738 write_memory (vparam, val, TYPE_LENGTH (type));
739 vparam = align_up (vparam + TYPE_LENGTH (type), 16);
742 else if ((TYPE_CODE (type) == TYPE_CODE_INT
743 || TYPE_CODE (type) == TYPE_CODE_ENUM
744 || TYPE_CODE (type) == TYPE_CODE_PTR)
745 && TYPE_LENGTH (type) <= 8)
747 /* Scalars and Pointers get sign[un]extended and go in
748 gpr3 .. gpr10. They can also end up in memory. */
751 /* Sign extend the value, then store it unsigned. */
752 ULONGEST word = unpack_long (type, val);
753 /* Convert any function code addresses into
755 if (TYPE_CODE (type) == TYPE_CODE_PTR
756 && TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC)
758 CORE_ADDR desc = word;
759 convert_code_addr_to_desc_addr (word, &desc);
763 regcache_cooked_write_unsigned (regcache,
764 tdep->ppc_gp0_regnum +
766 write_memory_unsigned_integer (gparam, tdep->wordsize,
770 gparam = align_up (gparam + TYPE_LENGTH (type), tdep->wordsize);
775 for (byte = 0; byte < TYPE_LENGTH (type);
776 byte += tdep->wordsize)
778 if (write_pass && greg <= 10)
780 gdb_byte regval[MAX_REGISTER_SIZE];
781 int len = TYPE_LENGTH (type) - byte;
782 if (len > tdep->wordsize)
783 len = tdep->wordsize;
784 memset (regval, 0, sizeof regval);
785 /* WARNING: cagney/2003-09-21: As best I can
786 tell, the ABI specifies that the value should
787 be left aligned. Unfortunately, GCC doesn't
788 do this - it instead right aligns even sized
789 values and puts odd sized values on the
790 stack. Work around that by putting both a
791 left and right aligned value into the
792 register (hopefully no one notices :-^).
794 /* Left aligned (8 byte values such as pointers
796 memcpy (regval, val + byte, len);
797 /* Right aligned (but only if even). */
798 if (len == 1 || len == 2 || len == 4)
799 memcpy (regval + tdep->wordsize - len,
801 regcache_cooked_write (regcache, greg, regval);
806 /* WARNING: cagney/2003-09-21: Strictly speaking, this
807 isn't necessary, unfortunately, GCC appears to get
808 "struct convention" parameter passing wrong putting
809 odd sized structures in memory instead of in a
810 register. Work around this by always writing the
811 value to memory. Fortunately, doing this
812 simplifies the code. */
813 write_memory (gparam, val, TYPE_LENGTH (type));
815 /* WARNING: cagney/2004-06-20: It appears that GCC
816 likes to put structures containing a single
817 floating-point member in an FP register instead of
818 general general purpose. */
819 /* Always consume parameter stack space. */
820 gparam = align_up (gparam + TYPE_LENGTH (type), tdep->wordsize);
826 /* Save the true region sizes ready for the second pass. */
827 vparam_size = vparam;
828 /* Make certain that the general parameter save area is at
829 least the minimum 8 registers (or doublewords) in size. */
831 gparam_size = 8 * tdep->wordsize;
833 gparam_size = gparam;
838 regcache_cooked_write_signed (regcache,
839 gdbarch_sp_regnum (current_gdbarch), sp);
841 /* Write the backchain (it occupies WORDSIZED bytes). */
842 write_memory_signed_integer (sp, tdep->wordsize, back_chain);
844 /* Point the inferior function call's return address at the dummy's
846 regcache_cooked_write_signed (regcache, tdep->ppc_lr_regnum, bp_addr);
848 /* Use the func_addr to find the descriptor, and use that to find
852 if (convert_code_addr_to_desc_addr (func_addr, &desc_addr))
854 /* The TOC is the second double word in the descriptor. */
856 read_memory_unsigned_integer (desc_addr + tdep->wordsize,
858 regcache_cooked_write_unsigned (regcache,
859 tdep->ppc_gp0_regnum + 2, toc);
867 /* The 64 bit ABI retun value convention.
869 Return non-zero if the return-value is stored in a register, return
870 0 if the return-value is instead stored on the stack (a.k.a.,
871 struct return convention).
873 For a return-value stored in a register: when WRITEBUF is non-NULL,
874 copy the buffer to the corresponding register return-value location
875 location; when READBUF is non-NULL, fill the buffer from the
876 corresponding register return-value location. */
877 enum return_value_convention
878 ppc64_sysv_abi_return_value (struct gdbarch *gdbarch, struct type *valtype,
879 struct regcache *regcache, gdb_byte *readbuf,
880 const gdb_byte *writebuf)
882 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
884 /* This function exists to support a calling convention that
885 requires floating-point registers. It shouldn't be used on
886 processors that lack them. */
887 gdb_assert (ppc_floating_point_unit_p (gdbarch));
889 /* Floats and doubles in F1. */
890 if (TYPE_CODE (valtype) == TYPE_CODE_FLT && TYPE_LENGTH (valtype) <= 8)
892 gdb_byte regval[MAX_REGISTER_SIZE];
893 struct type *regtype = register_type (gdbarch, tdep->ppc_fp0_regnum);
894 if (writebuf != NULL)
896 convert_typed_floating (writebuf, valtype, regval, regtype);
897 regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1, regval);
901 regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1, regval);
902 convert_typed_floating (regval, regtype, readbuf, valtype);
904 return RETURN_VALUE_REGISTER_CONVENTION;
906 /* Integers in r3. */
907 if ((TYPE_CODE (valtype) == TYPE_CODE_INT
908 || TYPE_CODE (valtype) == TYPE_CODE_ENUM)
909 && TYPE_LENGTH (valtype) <= 8)
911 if (writebuf != NULL)
913 /* Be careful to sign extend the value. */
914 regcache_cooked_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
915 unpack_long (valtype, writebuf));
919 /* Extract the integer from r3. Since this is truncating the
920 value, there isn't a sign extension problem. */
922 regcache_cooked_read_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
924 store_unsigned_integer (readbuf, TYPE_LENGTH (valtype), regval);
926 return RETURN_VALUE_REGISTER_CONVENTION;
928 /* All pointers live in r3. */
929 if (TYPE_CODE (valtype) == TYPE_CODE_PTR)
931 /* All pointers live in r3. */
932 if (writebuf != NULL)
933 regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3, writebuf);
935 regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 3, readbuf);
936 return RETURN_VALUE_REGISTER_CONVENTION;
938 /* Array type has more than one use. */
939 if (TYPE_CODE (valtype) == TYPE_CODE_ARRAY)
941 /* Small character arrays are returned, right justified, in r3. */
942 if (TYPE_LENGTH (valtype) <= 8
943 && TYPE_CODE (TYPE_TARGET_TYPE (valtype)) == TYPE_CODE_INT
944 && TYPE_LENGTH (TYPE_TARGET_TYPE (valtype)) == 1)
946 int offset = (register_size (gdbarch, tdep->ppc_gp0_regnum + 3)
947 - TYPE_LENGTH (valtype));
948 if (writebuf != NULL)
949 regcache_cooked_write_part (regcache, tdep->ppc_gp0_regnum + 3,
950 offset, TYPE_LENGTH (valtype), writebuf);
952 regcache_cooked_read_part (regcache, tdep->ppc_gp0_regnum + 3,
953 offset, TYPE_LENGTH (valtype), readbuf);
954 return RETURN_VALUE_REGISTER_CONVENTION;
956 /* A VMX vector is returned in v2. */
957 if (TYPE_CODE (valtype) == TYPE_CODE_ARRAY
958 && TYPE_VECTOR (valtype) && tdep->ppc_vr0_regnum >= 0)
961 regcache_cooked_read (regcache, tdep->ppc_vr0_regnum + 2, readbuf);
963 regcache_cooked_write (regcache, tdep->ppc_vr0_regnum + 2, writebuf);
964 return RETURN_VALUE_REGISTER_CONVENTION;
967 /* Big floating point values get stored in adjacent floating
968 point registers, starting with F1. */
969 if (TYPE_CODE (valtype) == TYPE_CODE_FLT
970 && (TYPE_LENGTH (valtype) == 16 || TYPE_LENGTH (valtype) == 32))
972 if (writebuf || readbuf != NULL)
975 for (i = 0; i < TYPE_LENGTH (valtype) / 8; i++)
977 if (writebuf != NULL)
978 regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1 + i,
979 (const bfd_byte *) writebuf + i * 8);
981 regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1 + i,
982 (bfd_byte *) readbuf + i * 8);
985 return RETURN_VALUE_REGISTER_CONVENTION;
987 /* Complex values get returned in f1:f2, need to convert. */
988 if (TYPE_CODE (valtype) == TYPE_CODE_COMPLEX
989 && (TYPE_LENGTH (valtype) == 8 || TYPE_LENGTH (valtype) == 16))
991 if (regcache != NULL)
994 for (i = 0; i < 2; i++)
996 gdb_byte regval[MAX_REGISTER_SIZE];
997 struct type *regtype =
998 register_type (current_gdbarch, tdep->ppc_fp0_regnum);
999 if (writebuf != NULL)
1001 convert_typed_floating ((const bfd_byte *) writebuf +
1002 i * (TYPE_LENGTH (valtype) / 2),
1003 valtype, regval, regtype);
1004 regcache_cooked_write (regcache,
1005 tdep->ppc_fp0_regnum + 1 + i,
1008 if (readbuf != NULL)
1010 regcache_cooked_read (regcache,
1011 tdep->ppc_fp0_regnum + 1 + i,
1013 convert_typed_floating (regval, regtype,
1014 (bfd_byte *) readbuf +
1015 i * (TYPE_LENGTH (valtype) / 2),
1020 return RETURN_VALUE_REGISTER_CONVENTION;
1022 /* Big complex values get stored in f1:f4. */
1023 if (TYPE_CODE (valtype) == TYPE_CODE_COMPLEX && TYPE_LENGTH (valtype) == 32)
1025 if (regcache != NULL)
1028 for (i = 0; i < 4; i++)
1030 if (writebuf != NULL)
1031 regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1 + i,
1032 (const bfd_byte *) writebuf + i * 8);
1033 if (readbuf != NULL)
1034 regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1 + i,
1035 (bfd_byte *) readbuf + i * 8);
1038 return RETURN_VALUE_REGISTER_CONVENTION;
1040 return RETURN_VALUE_STRUCT_CONVENTION;
1044 ppc64_sysv_abi_adjust_breakpoint_address (struct gdbarch *gdbarch,
1047 /* PPC64 SYSV specifies that the minimal-symbol "FN" should point at
1048 a function-descriptor while the corresponding minimal-symbol
1049 ".FN" should point at the entry point. Consequently, a command
1050 like "break FN" applied to an object file with only minimal
1051 symbols, will insert the breakpoint into the descriptor at "FN"
1052 and not the function at ".FN". Avoid this confusion by adjusting
1053 any attempt to set a descriptor breakpoint into a corresponding
1054 function breakpoint. Note that GDB warns the user when this
1055 adjustment is applied - that's ok as otherwise the user will have
1056 no way of knowing why their breakpoint at "FN" resulted in the
1057 program stopping at ".FN". */
1058 return gdbarch_convert_from_func_ptr_addr (gdbarch, bpaddr, ¤t_target);