1 /* Target-machine dependent code for Motorola MCore for GDB, the GNU debugger
2 Copyright 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
29 #include "arch-utils.h"
30 #include "gdb_string.h"
33 static CORE_ADDR mcore_analyze_prologue (struct frame_info *fi, CORE_ADDR pc,
35 static int get_insn (CORE_ADDR pc);
42 /* All registers are 4 bytes long. */
43 #define MCORE_REG_SIZE 4
44 #define MCORE_NUM_REGS 65
46 /* Some useful register numbers. */
48 #define FIRST_ARGREG 2
50 #define RETVAL_REGNUM 2
53 /* Additional info that we use for managing frames */
54 struct frame_extra_info
56 /* A generic status word */
59 /* Size of this frame */
62 /* The register that is acting as a frame pointer, if
63 it is being used. This is undefined if status
64 does not contain the flag MY_FRAME_IN_FP. */
68 /* frame_extra_info status flags */
70 /* The base of the current frame is actually in the stack pointer.
71 This happens when there is no frame pointer (MCore ABI does not
72 require a frame pointer) or when we're stopped in the prologue or
73 epilogue itself. In these cases, mcore_analyze_prologue will need
74 to update fi->frame before returning or analyzing the register
76 #define MY_FRAME_IN_SP 0x1
78 /* The base of the current frame is in a frame pointer register.
79 This register is noted in frame_extra_info->fp_regnum.
81 Note that the existence of an FP might also indicate that the
82 function has called alloca. */
83 #define MY_FRAME_IN_FP 0x2
85 /* This flag is set to indicate that this frame is the top-most
86 frame. This tells frame chain not to bother trying to unwind
88 #define NO_MORE_FRAMES 0x4
90 /* Instruction macros used for analyzing the prologue */
91 #define IS_SUBI0(x) (((x) & 0xfe0f) == 0x2400) /* subi r0,oimm5 */
92 #define IS_STM(x) (((x) & 0xfff0) == 0x0070) /* stm rf-r15,r0 */
93 #define IS_STWx0(x) (((x) & 0xf00f) == 0x9000) /* stw rz,(r0,disp) */
94 #define IS_STWxy(x) (((x) & 0xf000) == 0x9000) /* stw rx,(ry,disp) */
95 #define IS_MOVx0(x) (((x) & 0xfff0) == 0x1200) /* mov rn,r0 */
96 #define IS_LRW1(x) (((x) & 0xff00) == 0x7100) /* lrw r1,literal */
97 #define IS_MOVI1(x) (((x) & 0xf80f) == 0x6001) /* movi r1,imm7 */
98 #define IS_BGENI1(x) (((x) & 0xfe0f) == 0x3201) /* bgeni r1,imm5 */
99 #define IS_BMASKI1(x) (((x) & 0xfe0f) == 0x2C01) /* bmaski r1,imm5 */
100 #define IS_ADDI1(x) (((x) & 0xfe0f) == 0x2001) /* addi r1,oimm5 */
101 #define IS_SUBI1(x) (((x) & 0xfe0f) == 0x2401) /* subi r1,oimm5 */
102 #define IS_RSUBI1(x) (((x) & 0xfe0f) == 0x2801) /* rsubi r1,imm5 */
103 #define IS_NOT1(x) (((x) & 0xffff) == 0x01f1) /* not r1 */
104 #define IS_ROTLI1(x) (((x) & 0xfe0f) == 0x3801) /* rotli r1,imm5 */
105 #define IS_BSETI1(x) (((x) & 0xfe0f) == 0x3401) /* bseti r1,imm5 */
106 #define IS_BCLRI1(x) (((x) & 0xfe0f) == 0x3001) /* bclri r1,imm5 */
107 #define IS_IXH1(x) (((x) & 0xffff) == 0x1d11) /* ixh r1,r1 */
108 #define IS_IXW1(x) (((x) & 0xffff) == 0x1511) /* ixw r1,r1 */
109 #define IS_SUB01(x) (((x) & 0xffff) == 0x0510) /* subu r0,r1 */
110 #define IS_RTS(x) (((x) & 0xffff) == 0x00cf) /* jmp r15 */
112 #define IS_R1_ADJUSTER(x) \
113 (IS_ADDI1(x) || IS_SUBI1(x) || IS_ROTLI1(x) || IS_BSETI1(x) \
114 || IS_BCLRI1(x) || IS_RSUBI1(x) || IS_NOT1(x) \
115 || IS_IXH1(x) || IS_IXW1(x))
120 mcore_dump_insn (char *commnt, CORE_ADDR pc, int insn)
124 printf_filtered ("MCORE: %s %08x %08x ",
125 commnt, (unsigned int) pc, (unsigned int) insn);
126 gdb_print_insn (pc, gdb_stdout);
127 printf_filtered ("\n");
130 #define mcore_insn_debug(args) { if (mcore_debug) printf_filtered args; }
131 #else /* !MCORE_DEBUG */
132 #define mcore_dump_insn(a,b,c) {}
133 #define mcore_insn_debug(args) {}
138 mcore_register_virtual_type (int regnum)
140 if (regnum < 0 || regnum >= MCORE_NUM_REGS)
141 internal_error (__FILE__, __LINE__,
142 "mcore_register_virtual_type: illegal register number %d",
145 return builtin_type_int;
149 mcore_register_byte (int regnum)
151 if (regnum < 0 || regnum >= MCORE_NUM_REGS)
152 internal_error (__FILE__, __LINE__,
153 "mcore_register_byte: illegal register number %d",
156 return (regnum * MCORE_REG_SIZE);
160 mcore_register_size (int regnum)
163 if (regnum < 0 || regnum >= MCORE_NUM_REGS)
164 internal_error (__FILE__, __LINE__,
165 "mcore_register_size: illegal register number %d",
168 return MCORE_REG_SIZE;
171 /* The registers of the Motorola MCore processors */
174 mcore_register_name (int regnum)
177 static char *register_names[] = {
178 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
179 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
180 "ar0", "ar1", "ar2", "ar3", "ar4", "ar5", "ar6", "ar7",
181 "ar8", "ar9", "ar10", "ar11", "ar12", "ar13", "ar14", "ar15",
182 "psr", "vbr", "epsr", "fpsr", "epc", "fpc", "ss0", "ss1",
183 "ss2", "ss3", "ss4", "gcr", "gsr", "cr13", "cr14", "cr15",
184 "cr16", "cr17", "cr18", "cr19", "cr20", "cr21", "cr22", "cr23",
185 "cr24", "cr25", "cr26", "cr27", "cr28", "cr29", "cr30", "cr31",
190 regnum >= sizeof (register_names) / sizeof (register_names[0]))
191 internal_error (__FILE__, __LINE__,
192 "mcore_register_name: illegal register number %d",
195 return register_names[regnum];
198 /* Given the address at which to insert a breakpoint (BP_ADDR),
199 what will that breakpoint be?
201 For MCore, we have a breakpoint instruction. Since all MCore
202 instructions are 16 bits, this is all we need, regardless of
203 address. bpkt = 0x0000 */
205 const unsigned char *
206 mcore_breakpoint_from_pc (CORE_ADDR * bp_addr, int *bp_size)
208 static char breakpoint[] =
215 mcore_saved_pc_after_call (struct frame_info *frame)
217 return read_register (PR_REGNUM);
220 /* This is currently handled by init_extra_frame_info. */
222 mcore_frame_init_saved_regs (struct frame_info *frame)
227 /* This is currently handled by mcore_push_arguments */
229 mcore_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
235 mcore_reg_struct_has_addr (int gcc_p, struct type *type)
241 /* Helper function for several routines below. This funtion simply
242 sets up a fake, aka dummy, frame (not a _call_ dummy frame) that
243 we can analyze with mcore_analyze_prologue. */
245 static struct frame_info *
246 analyze_dummy_frame (CORE_ADDR pc, CORE_ADDR frame)
248 static struct frame_info *dummy = NULL;
252 struct frame_extra_info *extra_info;
253 CORE_ADDR *saved_regs;
254 dummy = deprecated_frame_xmalloc ();
255 saved_regs = (CORE_ADDR *) xmalloc (SIZEOF_FRAME_SAVED_REGS);
256 deprecated_set_frame_saved_regs_hack (dummy, saved_regs);
257 extra_info = XMALLOC (struct frame_extra_info);
258 deprecated_set_frame_extra_info_hack (dummy, extra_info);
261 deprecated_set_frame_next_hack (dummy, NULL);
262 deprecated_set_frame_prev_hack (dummy, NULL);
263 deprecated_update_frame_pc_hack (dummy, pc);
264 deprecated_update_frame_base_hack (dummy, frame);
265 get_frame_extra_info (dummy)->status = 0;
266 get_frame_extra_info (dummy)->framesize = 0;
267 memset (get_frame_saved_regs (dummy), '\000', SIZEOF_FRAME_SAVED_REGS);
268 mcore_analyze_prologue (dummy, 0, 0);
272 /* Function prologues on the Motorola MCore processors consist of:
274 - adjustments to the stack pointer (r1 used as scratch register)
275 - store word/multiples that use r0 as the base address
276 - making a copy of r0 into another register (a "frame" pointer)
278 Note that the MCore really doesn't have a real frame pointer.
279 Instead, the compiler may copy the SP into a register (usually
280 r8) to act as an arg pointer. For our target-dependent purposes,
281 the frame info's "frame" member will be the beginning of the
282 frame. The SP could, in fact, point below this.
284 The prologue ends when an instruction fails to meet either of
285 the first two criteria or when an FP is made. We make a special
286 exception for gcc. When compiling unoptimized code, gcc will
287 setup stack slots. We need to make sure that we skip the filling
288 of these stack slots as much as possible. This is only done
289 when SKIP_PROLOGUE is set, so that it does not mess up
292 /* Analyze the prologue of frame FI to determine where registers are saved,
293 the end of the prologue, etc. Return the address of the first line
294 of "real" code (i.e., the end of the prologue). */
297 mcore_analyze_prologue (struct frame_info *fi, CORE_ADDR pc, int skip_prologue)
299 CORE_ADDR func_addr, func_end, addr, stop;
300 CORE_ADDR stack_size;
303 int fp_regnum = 0; /* dummy, valid when (flags & MY_FRAME_IN_FP) */
306 int register_offsets[NUM_REGS];
309 /* If provided, use the PC in the frame to look up the
310 start of this function. */
311 pc = (fi == NULL ? pc : get_frame_pc (fi));
313 /* Find the start of this function. */
314 status = find_pc_partial_function (pc, &name, &func_addr, &func_end);
316 /* If the start of this function could not be found or if the debbuger
317 is stopped at the first instruction of the prologue, do nothing. */
321 /* If the debugger is entry function, give up. */
322 if (func_addr == entry_point_address ())
325 get_frame_extra_info (fi)->status |= NO_MORE_FRAMES;
329 /* At the start of a function, our frame is in the stack pointer. */
330 flags = MY_FRAME_IN_SP;
332 /* Start decoding the prologue. We start by checking two special cases:
334 1. We're about to return
335 2. We're at the first insn of the prologue.
337 If we're about to return, our frame has already been deallocated.
338 If we are stopped at the first instruction of a prologue,
339 then our frame has not yet been set up. */
341 /* Get the first insn from memory (all MCore instructions are 16 bits) */
342 mcore_insn_debug (("MCORE: starting prologue decoding\n"));
343 insn = get_insn (pc);
344 mcore_dump_insn ("got 1: ", pc, insn);
346 /* Check for return. */
347 if (fi != NULL && IS_RTS (insn))
349 mcore_insn_debug (("MCORE: got jmp r15"));
350 if (get_next_frame (fi) == NULL)
351 deprecated_update_frame_base_hack (fi, read_sp ());
352 return get_frame_pc (fi);
355 /* Check for first insn of prologue */
356 if (fi != NULL && get_frame_pc (fi) == func_addr)
358 if (get_next_frame (fi) == NULL)
359 deprecated_update_frame_base_hack (fi, read_sp ());
360 return get_frame_pc (fi);
363 /* Figure out where to stop scanning */
364 stop = (fi ? get_frame_pc (fi) : func_end);
366 /* Don't walk off the end of the function */
367 stop = (stop > func_end ? func_end : stop);
369 /* REGISTER_OFFSETS will contain offsets, from the top of the frame
370 (NOT the frame pointer), for the various saved registers or -1
371 if the register is not saved. */
372 for (rn = 0; rn < NUM_REGS; rn++)
373 register_offsets[rn] = -1;
375 /* Analyze the prologue. Things we determine from analyzing the
377 * the size of the frame
378 * where saved registers are located (and which are saved)
380 mcore_insn_debug (("MCORE: Scanning prologue: func_addr=0x%x, stop=0x%x\n",
381 (unsigned int) func_addr, (unsigned int) stop));
384 for (addr = func_addr; addr < stop; addr += 2)
387 insn = get_insn (addr);
388 mcore_dump_insn ("got 2: ", addr, insn);
392 int offset = 1 + ((insn >> 4) & 0x1f);
393 mcore_insn_debug (("MCORE: got subi r0,%d; continuing\n", offset));
397 else if (IS_STM (insn))
399 /* Spill register(s) */
403 /* BIG WARNING! The MCore ABI does not restrict functions
404 to taking only one stack allocation. Therefore, when
405 we save a register, we record the offset of where it was
406 saved relative to the current framesize. This will
407 then give an offset from the SP upon entry to our
408 function. Remember, framesize is NOT constant until
409 we're done scanning the prologue. */
410 start_register = (insn & 0xf);
411 mcore_insn_debug (("MCORE: got stm r%d-r15,(r0)\n", start_register));
413 for (rn = start_register, offset = 0; rn <= 15; rn++, offset += 4)
415 register_offsets[rn] = framesize - offset;
416 mcore_insn_debug (("MCORE: r%d saved at 0x%x (offset %d)\n", rn,
417 register_offsets[rn], offset));
419 mcore_insn_debug (("MCORE: continuing\n"));
422 else if (IS_STWx0 (insn))
424 /* Spill register: see note for IS_STM above. */
427 rn = (insn >> 8) & 0xf;
428 imm = (insn >> 4) & 0xf;
429 register_offsets[rn] = framesize - (imm << 2);
430 mcore_insn_debug (("MCORE: r%d saved at offset 0x%x\n", rn, register_offsets[rn]));
431 mcore_insn_debug (("MCORE: continuing\n"));
434 else if (IS_MOVx0 (insn))
436 /* We have a frame pointer, so this prologue is over. Note
437 the register which is acting as the frame pointer. */
438 flags |= MY_FRAME_IN_FP;
439 flags &= ~MY_FRAME_IN_SP;
440 fp_regnum = insn & 0xf;
441 mcore_insn_debug (("MCORE: Found a frame pointer: r%d\n", fp_regnum));
443 /* If we found an FP, we're at the end of the prologue. */
444 mcore_insn_debug (("MCORE: end of prologue\n"));
448 /* If we're decoding prologue, stop here. */
452 else if (IS_STWxy (insn) && (flags & MY_FRAME_IN_FP) && ((insn & 0xf) == fp_regnum))
454 /* Special case. Skip over stack slot allocs, too. */
455 mcore_insn_debug (("MCORE: push arg onto stack.\n"));
458 else if (IS_LRW1 (insn) || IS_MOVI1 (insn)
459 || IS_BGENI1 (insn) || IS_BMASKI1 (insn))
465 mcore_insn_debug (("MCORE: looking at large frame\n"));
469 read_memory_integer ((addr + 2 + ((insn & 0xff) << 2)) & 0xfffffffc, 4);
471 else if (IS_MOVI1 (insn))
472 adjust = (insn >> 4) & 0x7f;
473 else if (IS_BGENI1 (insn))
474 adjust = 1 << ((insn >> 4) & 0x1f);
475 else /* IS_BMASKI (insn) */
476 adjust = (1 << (adjust >> 4) & 0x1f) - 1;
478 mcore_insn_debug (("MCORE: base framesize=0x%x\n", adjust));
480 /* May have zero or more insns which modify r1 */
481 mcore_insn_debug (("MCORE: looking for r1 adjusters...\n"));
483 insn2 = get_insn (addr + offset);
484 while (IS_R1_ADJUSTER (insn2))
488 imm = (insn2 >> 4) & 0x1f;
489 mcore_dump_insn ("got 3: ", addr + offset, insn);
490 if (IS_ADDI1 (insn2))
493 mcore_insn_debug (("MCORE: addi r1,%d\n", imm + 1));
495 else if (IS_SUBI1 (insn2))
498 mcore_insn_debug (("MCORE: subi r1,%d\n", imm + 1));
500 else if (IS_RSUBI1 (insn2))
502 adjust = imm - adjust;
503 mcore_insn_debug (("MCORE: rsubi r1,%d\n", imm + 1));
505 else if (IS_NOT1 (insn2))
508 mcore_insn_debug (("MCORE: not r1\n"));
510 else if (IS_ROTLI1 (insn2))
513 mcore_insn_debug (("MCORE: rotli r1,%d\n", imm + 1));
515 else if (IS_BSETI1 (insn2))
517 adjust |= (1 << imm);
518 mcore_insn_debug (("MCORE: bseti r1,%d\n", imm));
520 else if (IS_BCLRI1 (insn2))
522 adjust &= ~(1 << imm);
523 mcore_insn_debug (("MCORE: bclri r1,%d\n", imm));
525 else if (IS_IXH1 (insn2))
528 mcore_insn_debug (("MCORE: ix.h r1,r1\n"));
530 else if (IS_IXW1 (insn2))
533 mcore_insn_debug (("MCORE: ix.w r1,r1\n"));
537 insn2 = get_insn (addr + offset);
540 mcore_insn_debug (("MCORE: done looking for r1 adjusters\n"));
542 /* If the next insn adjusts the stack pointer, we keep everything;
543 if not, we scrap it and we've found the end of the prologue. */
544 if (IS_SUB01 (insn2))
548 mcore_insn_debug (("MCORE: found stack adjustment of 0x%x bytes.\n", adjust));
549 mcore_insn_debug (("MCORE: skipping to new address 0x%x\n", addr));
550 mcore_insn_debug (("MCORE: continuing\n"));
554 /* None of these instructions are prologue, so don't touch
556 mcore_insn_debug (("MCORE: no subu r1,r0, NOT altering framesize.\n"));
560 /* This is not a prologue insn, so stop here. */
561 mcore_insn_debug (("MCORE: insn is not a prologue insn -- ending scan\n"));
565 mcore_insn_debug (("MCORE: done analyzing prologue\n"));
566 mcore_insn_debug (("MCORE: prologue end = 0x%x\n", addr));
568 /* Save everything we have learned about this frame into FI. */
571 get_frame_extra_info (fi)->framesize = framesize;
572 get_frame_extra_info (fi)->fp_regnum = fp_regnum;
573 get_frame_extra_info (fi)->status = flags;
575 /* Fix the frame pointer. When gcc uses r8 as a frame pointer,
576 it is really an arg ptr. We adjust fi->frame to be a "real"
578 if (get_next_frame (fi) == NULL)
580 if (get_frame_extra_info (fi)->status & MY_FRAME_IN_SP)
581 deprecated_update_frame_base_hack (fi, read_sp () + framesize);
583 deprecated_update_frame_base_hack (fi, read_register (fp_regnum) + framesize);
586 /* Note where saved registers are stored. The offsets in REGISTER_OFFSETS
587 are computed relative to the top of the frame. */
588 for (rn = 0; rn < NUM_REGS; rn++)
590 if (register_offsets[rn] >= 0)
592 get_frame_saved_regs (fi)[rn] = get_frame_base (fi) - register_offsets[rn];
593 mcore_insn_debug (("Saved register %s stored at 0x%08x, value=0x%08x\n",
594 mcore_register_names[rn], fi->saved_regs[rn],
595 read_memory_integer (fi->saved_regs[rn], 4)));
600 /* Return addr of first non-prologue insn. */
604 /* Given a GDB frame, determine the address of the calling function's
605 frame. This will be used to create a new GDB frame struct, and
606 then DEPRECATED_INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC
607 will be called for the new frame. */
610 mcore_frame_chain (struct frame_info * fi)
612 struct frame_info *dummy;
613 CORE_ADDR callers_addr;
615 /* Analyze the prologue of this function. */
616 if (get_frame_extra_info (fi)->status == 0)
617 mcore_analyze_prologue (fi, 0, 0);
619 /* If mcore_analyze_prologue set NO_MORE_FRAMES, quit now. */
620 if (get_frame_extra_info (fi)->status & NO_MORE_FRAMES)
623 /* Now that we've analyzed our prologue, we can start to ask
624 for information about our caller. The easiest way to do
625 this is to analyze our caller's prologue.
627 If our caller has a frame pointer, then we need to find
628 the value of that register upon entry to our frame.
629 This value is either in fi->saved_regs[rn] if it's saved,
630 or it's still in a register.
632 If our caller does not have a frame pointer, then his frame base
633 is <our base> + -<caller's frame size>. */
634 dummy = analyze_dummy_frame (DEPRECATED_FRAME_SAVED_PC (fi), get_frame_base (fi));
636 if (get_frame_extra_info (dummy)->status & MY_FRAME_IN_FP)
638 int fp = get_frame_extra_info (dummy)->fp_regnum;
640 /* Our caller has a frame pointer. */
641 if (get_frame_saved_regs (fi)[fp] != 0)
643 /* The "FP" was saved on the stack. Don't forget to adjust
644 the "FP" with the framesize to get a real FP. */
645 callers_addr = read_memory_integer (get_frame_saved_regs (fi)[fp],
646 DEPRECATED_REGISTER_SIZE)
647 + get_frame_extra_info (dummy)->framesize;
651 /* It's still in the register. Don't forget to adjust
652 the "FP" with the framesize to get a real FP. */
653 callers_addr = read_register (fp) + get_frame_extra_info (dummy)->framesize;
658 /* Our caller does not have a frame pointer. */
659 callers_addr = get_frame_base (fi) + get_frame_extra_info (dummy)->framesize;
665 /* Skip the prologue of the function at PC. */
668 mcore_skip_prologue (CORE_ADDR pc)
670 CORE_ADDR func_addr, func_end;
671 struct symtab_and_line sal;
673 /* If we have line debugging information, then the end of the
674 prologue should be the first assembly instruction of the first
676 if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
678 sal = find_pc_line (func_addr, 0);
679 if (sal.end && sal.end < func_end)
683 return mcore_analyze_prologue (NULL, pc, 1);
686 /* Return the address at which function arguments are offset. */
688 mcore_frame_args_address (struct frame_info * fi)
690 return get_frame_base (fi) - get_frame_extra_info (fi)->framesize;
694 mcore_frame_locals_address (struct frame_info * fi)
696 return get_frame_base (fi) - get_frame_extra_info (fi)->framesize;
699 /* Return the frame pointer in use at address PC. */
702 mcore_virtual_frame_pointer (CORE_ADDR pc, int *reg, LONGEST *offset)
704 struct frame_info *dummy = analyze_dummy_frame (pc, 0);
705 if (get_frame_extra_info (dummy)->status & MY_FRAME_IN_SP)
712 *reg = get_frame_extra_info (dummy)->fp_regnum;
717 /* Find the value of register REGNUM in frame FI. */
720 mcore_find_callers_reg (struct frame_info *fi, int regnum)
722 for (; fi != NULL; fi = get_next_frame (fi))
724 if (DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (fi), get_frame_base (fi),
725 get_frame_base (fi)))
726 return deprecated_read_register_dummy (get_frame_pc (fi),
727 get_frame_base (fi), regnum);
728 else if (get_frame_saved_regs (fi)[regnum] != 0)
729 return read_memory_integer (get_frame_saved_regs (fi)[regnum],
730 DEPRECATED_REGISTER_SIZE);
733 return read_register (regnum);
736 /* Find the saved pc in frame FI. */
739 mcore_frame_saved_pc (struct frame_info * fi)
742 if (DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (fi), get_frame_base (fi),
743 get_frame_base (fi)))
744 return deprecated_read_register_dummy (get_frame_pc (fi),
745 get_frame_base (fi), PC_REGNUM);
747 return mcore_find_callers_reg (fi, PR_REGNUM);
750 /* INFERIOR FUNCTION CALLS */
752 /* This routine gets called when either the user uses the "return"
753 command, or the call dummy breakpoint gets hit. */
756 mcore_pop_frame (void)
759 struct frame_info *fi = get_current_frame ();
761 if (DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (fi), get_frame_base (fi),
762 get_frame_base (fi)))
763 generic_pop_dummy_frame ();
766 /* Write out the PC we saved. */
767 write_register (PC_REGNUM, DEPRECATED_FRAME_SAVED_PC (fi));
769 /* Restore any saved registers. */
770 for (rn = 0; rn < NUM_REGS; rn++)
772 if (get_frame_saved_regs (fi)[rn] != 0)
776 value = read_memory_unsigned_integer (get_frame_saved_regs (fi)[rn],
777 DEPRECATED_REGISTER_SIZE);
778 write_register (rn, value);
782 /* Actually cut back the stack. */
783 write_register (SP_REGNUM, get_frame_base (fi));
786 /* Finally, throw away any cached frame information. */
787 flush_cached_frames ();
790 /* Setup arguments and PR for a call to the target. First six arguments
791 go in FIRST_ARGREG -> LAST_ARGREG, subsequent args go on to the stack.
793 - Types with lengths greater than DEPRECATED_REGISTER_SIZE may not
794 be split between registers and the stack, and they must start in an
795 even-numbered register. Subsequent args will go onto the stack.
797 * Structs may be split between registers and stack, left-aligned.
799 * If the function returns a struct which will not fit into registers (it's
800 more than eight bytes), we must allocate for that, too. Gdb will tell
801 us where this buffer is (STRUCT_ADDR), and we simply place it into
802 FIRST_ARGREG, since the MCORE treats struct returns (of less than eight
803 bytes) as hidden first arguments. */
806 mcore_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
807 int struct_return, CORE_ADDR struct_addr)
819 stack_args = (struct stack_arg *) alloca (nargs * sizeof (struct stack_arg));
821 argreg = FIRST_ARGREG;
823 /* Align the stack. This is mostly a nop, but not always. It will be needed
824 if we call a function which has argument overflow. */
827 /* If this function returns a struct which does not fit in the
828 return registers, we must pass a buffer to the function
829 which it can use to save the return value. */
831 write_register (argreg++, struct_addr);
833 /* FIXME: what about unions? */
834 for (argnum = 0; argnum < nargs; argnum++)
836 char *val = (char *) VALUE_CONTENTS (args[argnum]);
837 int len = TYPE_LENGTH (VALUE_TYPE (args[argnum]));
838 struct type *type = VALUE_TYPE (args[argnum]);
841 mcore_insn_debug (("MCORE PUSH: argreg=%d; len=%d; %s\n",
842 argreg, len, TYPE_CODE (type) == TYPE_CODE_STRUCT ? "struct" : "not struct"));
843 /* Arguments larger than a register must start in an even
844 numbered register. */
847 if (TYPE_CODE (type) != TYPE_CODE_STRUCT && len > DEPRECATED_REGISTER_SIZE && argreg % 2)
849 mcore_insn_debug (("MCORE PUSH: %d > DEPRECATED_REGISTER_SIZE: and %s is not even\n",
850 len, mcore_register_names[argreg]));
854 if ((argreg <= LAST_ARGREG && len <= (LAST_ARGREG - argreg + 1) * DEPRECATED_REGISTER_SIZE)
855 || (TYPE_CODE (type) == TYPE_CODE_STRUCT))
857 /* Something that will fit entirely into registers (or a struct
858 which may be split between registers and stack). */
859 mcore_insn_debug (("MCORE PUSH: arg %d going into regs\n", argnum));
861 if (TYPE_CODE (type) == TYPE_CODE_STRUCT && olen < DEPRECATED_REGISTER_SIZE)
863 /* Small structs must be right aligned within the register,
864 the most significant bits are undefined. */
865 write_register (argreg, extract_unsigned_integer (val, len));
870 while (len > 0 && argreg <= LAST_ARGREG)
872 write_register (argreg, extract_unsigned_integer (val, DEPRECATED_REGISTER_SIZE));
874 val += DEPRECATED_REGISTER_SIZE;
875 len -= DEPRECATED_REGISTER_SIZE;
878 /* Any remainder for the stack is noted below... */
880 else if (TYPE_CODE (VALUE_TYPE (args[argnum])) != TYPE_CODE_STRUCT
881 && len > DEPRECATED_REGISTER_SIZE)
883 /* All subsequent args go onto the stack. */
884 mcore_insn_debug (("MCORE PUSH: does not fit into regs, going onto stack\n"));
885 argnum = LAST_ARGREG + 1;
890 /* Note that this must be saved onto the stack */
891 mcore_insn_debug (("MCORE PUSH: adding arg %d to stack\n", argnum));
892 stack_args[nstack_args].val = val;
893 stack_args[nstack_args].len = len;
899 /* We're done with registers and stack allocation. Now do the actual
901 while (nstack_args--)
903 sp -= stack_args[nstack_args].len;
904 write_memory (sp, stack_args[nstack_args].val, stack_args[nstack_args].len);
907 /* Return adjusted stack pointer. */
911 /* Store the return address for the call dummy. For MCore, we've
912 opted to use generic call dummies, so we simply store the
913 CALL_DUMMY_ADDRESS into the PR register (r15). */
916 mcore_push_return_address (CORE_ADDR pc, CORE_ADDR sp)
918 write_register (PR_REGNUM, CALL_DUMMY_ADDRESS ());
922 /* Setting/getting return values from functions.
924 The Motorola MCore processors use r2/r3 to return anything
925 not larger than 32 bits. Everything else goes into a caller-
926 supplied buffer, which is passed in via a hidden first
929 For gdb, this leaves us two routes, based on what
930 USE_STRUCT_CONVENTION (mcore_use_struct_convention) returns.
931 If this macro returns 1, gdb will call STORE_STRUCT_RETURN and
932 EXTRACT_STRUCT_VALUE_ADDRESS.
934 If USE_STRUCT_CONVENTION retruns 0, then gdb uses STORE_RETURN_VALUE
935 and EXTRACT_RETURN_VALUE to store/fetch the functions return value. */
937 /* Should we use EXTRACT_STRUCT_VALUE_ADDRESS instead of
938 EXTRACT_RETURN_VALUE? GCC_P is true if compiled with gcc
939 and TYPE is the type (which is known to be struct, union or array). */
942 mcore_use_struct_convention (int gcc_p, struct type *type)
944 return (TYPE_LENGTH (type) > 8);
947 /* Where is the return value saved? For MCore, a pointer to
948 this buffer was passed as a hidden first argument, so
949 just return that address. */
952 mcore_extract_struct_value_address (char *regbuf)
954 return extract_unsigned_integer (regbuf + REGISTER_BYTE (FIRST_ARGREG), DEPRECATED_REGISTER_SIZE);
957 /* Given a function which returns a value of type TYPE, extract the
958 the function's return value and place the result into VALBUF.
959 REGBUF is the register contents of the target. */
962 mcore_extract_return_value (struct type *type, char *regbuf, char *valbuf)
964 /* Copy the return value (starting) in RETVAL_REGNUM to VALBUF. */
965 /* Only getting the first byte! if len = 1, we need the last byte of
966 the register, not the first. */
967 memcpy (valbuf, regbuf + REGISTER_BYTE (RETVAL_REGNUM) +
968 (TYPE_LENGTH (type) < 4 ? 4 - TYPE_LENGTH (type) : 0), TYPE_LENGTH (type));
971 /* Store the return value in VALBUF (of type TYPE) where the caller
974 Values less than 32 bits are stored in r2, right justified and
975 sign or zero extended.
977 Values between 32 and 64 bits are stored in r2 (most
978 significant word) and r3 (least significant word, left justified).
979 Note that this includes structures of less than eight bytes, too. */
982 mcore_store_return_value (struct type *type, char *valbuf)
989 value_size = TYPE_LENGTH (type);
991 /* Return value fits into registers. */
992 return_size = (value_size + DEPRECATED_REGISTER_SIZE - 1) & ~(DEPRECATED_REGISTER_SIZE - 1);
993 offset = REGISTER_BYTE (RETVAL_REGNUM) + (return_size - value_size);
994 zeros = alloca (return_size);
995 memset (zeros, 0, return_size);
997 deprecated_write_register_bytes (REGISTER_BYTE (RETVAL_REGNUM), zeros,
999 deprecated_write_register_bytes (offset, valbuf, value_size);
1002 /* Initialize our target-dependent "stuff" for this newly created frame.
1004 This includes allocating space for saved registers and analyzing
1005 the prologue of this frame. */
1008 mcore_init_extra_frame_info (int fromleaf, struct frame_info *fi)
1010 if (fi && get_next_frame (fi))
1011 deprecated_update_frame_pc_hack (fi, DEPRECATED_FRAME_SAVED_PC (get_next_frame (fi)));
1013 frame_saved_regs_zalloc (fi);
1015 frame_extra_info_zalloc (fi, sizeof (struct frame_extra_info));
1016 get_frame_extra_info (fi)->status = 0;
1017 get_frame_extra_info (fi)->framesize = 0;
1019 if (DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (fi), get_frame_base (fi),
1020 get_frame_base (fi)))
1022 /* We need to setup fi->frame here because call_function_by_hand
1023 gets it wrong by assuming it's always FP. */
1024 deprecated_update_frame_base_hack (fi, deprecated_read_register_dummy (get_frame_pc (fi), get_frame_base (fi), SP_REGNUM));
1027 mcore_analyze_prologue (fi, 0, 0);
1030 /* Get an insturction from memory. */
1033 get_insn (CORE_ADDR pc)
1036 int status = read_memory_nobpt (pc, buf, 2);
1040 return extract_unsigned_integer (buf, 2);
1043 static struct gdbarch *
1044 mcore_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
1046 static LONGEST call_dummy_words[7] = { };
1047 struct gdbarch_tdep *tdep = NULL;
1048 struct gdbarch *gdbarch;
1050 /* find a candidate among the list of pre-declared architectures. */
1051 arches = gdbarch_list_lookup_by_info (arches, &info);
1053 return (arches->gdbarch);
1055 gdbarch = gdbarch_alloc (&info, 0);
1057 /* NOTE: cagney/2002-12-06: This can be deleted when this arch is
1058 ready to unwind the PC first (see frame.c:get_prev_frame()). */
1059 set_gdbarch_deprecated_init_frame_pc (gdbarch, init_frame_pc_default);
1063 /* All registers are 32 bits */
1064 set_gdbarch_deprecated_register_size (gdbarch, MCORE_REG_SIZE);
1065 set_gdbarch_deprecated_max_register_raw_size (gdbarch, MCORE_REG_SIZE);
1066 set_gdbarch_deprecated_max_register_virtual_size (gdbarch, MCORE_REG_SIZE);
1067 set_gdbarch_register_name (gdbarch, mcore_register_name);
1068 set_gdbarch_register_virtual_type (gdbarch, mcore_register_virtual_type);
1069 set_gdbarch_register_virtual_size (gdbarch, mcore_register_size);
1070 set_gdbarch_register_raw_size (gdbarch, mcore_register_size);
1071 set_gdbarch_register_byte (gdbarch, mcore_register_byte);
1072 set_gdbarch_deprecated_register_bytes (gdbarch, MCORE_REG_SIZE * MCORE_NUM_REGS);
1073 set_gdbarch_num_regs (gdbarch, MCORE_NUM_REGS);
1074 set_gdbarch_pc_regnum (gdbarch, 64);
1075 set_gdbarch_sp_regnum (gdbarch, 0);
1076 set_gdbarch_deprecated_fp_regnum (gdbarch, 0);
1080 set_gdbarch_deprecated_call_dummy_words (gdbarch, call_dummy_words);
1081 set_gdbarch_deprecated_sizeof_call_dummy_words (gdbarch, 0);
1082 set_gdbarch_save_dummy_frame_tos (gdbarch, generic_save_dummy_frame_tos);
1083 set_gdbarch_deprecated_saved_pc_after_call (gdbarch, mcore_saved_pc_after_call);
1084 set_gdbarch_function_start_offset (gdbarch, 0);
1085 set_gdbarch_decr_pc_after_break (gdbarch, 0);
1086 set_gdbarch_breakpoint_from_pc (gdbarch, mcore_breakpoint_from_pc);
1087 set_gdbarch_deprecated_push_return_address (gdbarch, mcore_push_return_address);
1088 set_gdbarch_deprecated_push_arguments (gdbarch, mcore_push_arguments);
1092 set_gdbarch_deprecated_init_extra_frame_info (gdbarch, mcore_init_extra_frame_info);
1093 set_gdbarch_deprecated_frame_chain (gdbarch, mcore_frame_chain);
1094 set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, mcore_frame_init_saved_regs);
1095 set_gdbarch_deprecated_frame_saved_pc (gdbarch, mcore_frame_saved_pc);
1096 set_gdbarch_deprecated_store_return_value (gdbarch, mcore_store_return_value);
1097 set_gdbarch_deprecated_extract_return_value (gdbarch,
1098 mcore_extract_return_value);
1099 set_gdbarch_deprecated_store_struct_return (gdbarch, mcore_store_struct_return);
1100 set_gdbarch_deprecated_extract_struct_value_address (gdbarch,
1101 mcore_extract_struct_value_address);
1102 set_gdbarch_skip_prologue (gdbarch, mcore_skip_prologue);
1103 set_gdbarch_frame_args_skip (gdbarch, 0);
1104 set_gdbarch_frame_args_address (gdbarch, mcore_frame_args_address);
1105 set_gdbarch_frame_locals_address (gdbarch, mcore_frame_locals_address);
1106 set_gdbarch_deprecated_pop_frame (gdbarch, mcore_pop_frame);
1107 set_gdbarch_virtual_frame_pointer (gdbarch, mcore_virtual_frame_pointer);
1111 /* Stack grows down. */
1112 set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
1113 set_gdbarch_use_struct_convention (gdbarch, mcore_use_struct_convention);
1114 set_gdbarch_believe_pcc_promotion (gdbarch, 1);
1115 /* MCore will never pass a sturcture by reference. It will always be split
1116 between registers and stack. */
1117 set_gdbarch_reg_struct_has_addr (gdbarch, mcore_reg_struct_has_addr);
1119 /* Should be using push_dummy_call. */
1120 set_gdbarch_deprecated_dummy_write_sp (gdbarch, deprecated_write_sp);
1126 mcore_dump_tdep (struct gdbarch *current_gdbarch, struct ui_file *file)
1131 extern initialize_file_ftype _initialize_mcore_tdep; /* -Wmissing-prototypes */
1134 _initialize_mcore_tdep (void)
1136 extern int print_insn_mcore (bfd_vma, disassemble_info *);
1137 gdbarch_register (bfd_arch_mcore, mcore_gdbarch_init, mcore_dump_tdep);
1138 deprecated_tm_print_insn = print_insn_mcore;
1141 add_show_from_set (add_set_cmd ("mcoredebug", no_class,
1142 var_boolean, (char *) &mcore_debug,
1143 "Set mcore debugging.\n", &setlist),