1 /* Target-machine dependent code for Motorola MCore for GDB, the GNU debugger
2 Copyright 1999, 2000, 2001 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"
31 /* Functions declared and used only in this file */
33 static CORE_ADDR
mcore_analyze_prologue (struct frame_info
*fi
, CORE_ADDR pc
, int skip_prologue
);
35 static struct frame_info
*analyze_dummy_frame (CORE_ADDR pc
, CORE_ADDR frame
);
37 static int get_insn (CORE_ADDR pc
);
39 /* Functions exported from this file */
41 int mcore_use_struct_convention (int gcc_p
, struct type
*type
);
43 void _initialize_mcore (void);
45 void mcore_init_extra_frame_info (int fromleaf
, struct frame_info
*fi
);
47 CORE_ADDR
mcore_frame_saved_pc (struct frame_info
*fi
);
49 CORE_ADDR
mcore_find_callers_reg (struct frame_info
*fi
, int regnum
);
51 CORE_ADDR
mcore_frame_args_address (struct frame_info
*fi
);
53 CORE_ADDR
mcore_frame_locals_address (struct frame_info
*fi
);
55 CORE_ADDR
mcore_push_return_address (CORE_ADDR pc
, CORE_ADDR sp
);
57 CORE_ADDR
mcore_push_arguments (int nargs
, struct value
** args
, CORE_ADDR sp
,
58 int struct_return
, CORE_ADDR struct_addr
);
60 void mcore_pop_frame ();
62 CORE_ADDR
mcore_skip_prologue (CORE_ADDR pc
);
64 CORE_ADDR
mcore_frame_chain (struct frame_info
*fi
);
66 const unsigned char *mcore_breakpoint_from_pc (CORE_ADDR
* bp_addr
, int *bp_size
);
68 int mcore_use_struct_convention (int gcc_p
, struct type
*type
);
70 void mcore_store_return_value (struct type
*type
, char *valbuf
);
72 CORE_ADDR
mcore_extract_struct_value_address (char *regbuf
);
74 void mcore_extract_return_value (struct type
*type
, char *regbuf
, char *valbuf
);
81 /* All registers are 4 bytes long. */
82 #define MCORE_REG_SIZE 4
83 #define MCORE_NUM_REGS 65
85 /* Some useful register numbers. */
87 #define FIRST_ARGREG 2
89 #define RETVAL_REGNUM 2
92 /* Additional info that we use for managing frames */
93 struct frame_extra_info
95 /* A generic status word */
98 /* Size of this frame */
101 /* The register that is acting as a frame pointer, if
102 it is being used. This is undefined if status
103 does not contain the flag MY_FRAME_IN_FP. */
107 /* frame_extra_info status flags */
109 /* The base of the current frame is actually in the stack pointer.
110 This happens when there is no frame pointer (MCore ABI does not
111 require a frame pointer) or when we're stopped in the prologue or
112 epilogue itself. In these cases, mcore_analyze_prologue will need
113 to update fi->frame before returning or analyzing the register
114 save instructions. */
115 #define MY_FRAME_IN_SP 0x1
117 /* The base of the current frame is in a frame pointer register.
118 This register is noted in frame_extra_info->fp_regnum.
120 Note that the existence of an FP might also indicate that the
121 function has called alloca. */
122 #define MY_FRAME_IN_FP 0x2
124 /* This flag is set to indicate that this frame is the top-most
125 frame. This tells frame chain not to bother trying to unwind
126 beyond this frame. */
127 #define NO_MORE_FRAMES 0x4
129 /* Instruction macros used for analyzing the prologue */
130 #define IS_SUBI0(x) (((x) & 0xfe0f) == 0x2400) /* subi r0,oimm5 */
131 #define IS_STM(x) (((x) & 0xfff0) == 0x0070) /* stm rf-r15,r0 */
132 #define IS_STWx0(x) (((x) & 0xf00f) == 0x9000) /* stw rz,(r0,disp) */
133 #define IS_STWxy(x) (((x) & 0xf000) == 0x9000) /* stw rx,(ry,disp) */
134 #define IS_MOVx0(x) (((x) & 0xfff0) == 0x1200) /* mov rn,r0 */
135 #define IS_LRW1(x) (((x) & 0xff00) == 0x7100) /* lrw r1,literal */
136 #define IS_MOVI1(x) (((x) & 0xf80f) == 0x6001) /* movi r1,imm7 */
137 #define IS_BGENI1(x) (((x) & 0xfe0f) == 0x3201) /* bgeni r1,imm5 */
138 #define IS_BMASKI1(x) (((x) & 0xfe0f) == 0x2C01) /* bmaski r1,imm5 */
139 #define IS_ADDI1(x) (((x) & 0xfe0f) == 0x2001) /* addi r1,oimm5 */
140 #define IS_SUBI1(x) (((x) & 0xfe0f) == 0x2401) /* subi r1,oimm5 */
141 #define IS_RSUBI1(x) (((x) & 0xfe0f) == 0x2801) /* rsubi r1,imm5 */
142 #define IS_NOT1(x) (((x) & 0xffff) == 0x01f1) /* not r1 */
143 #define IS_ROTLI1(x) (((x) & 0xfe0f) == 0x3801) /* rotli r1,imm5 */
144 #define IS_BSETI1(x) (((x) & 0xfe0f) == 0x3401) /* bseti r1,imm5 */
145 #define IS_BCLRI1(x) (((x) & 0xfe0f) == 0x3001) /* bclri r1,imm5 */
146 #define IS_IXH1(x) (((x) & 0xffff) == 0x1d11) /* ixh r1,r1 */
147 #define IS_IXW1(x) (((x) & 0xffff) == 0x1511) /* ixw r1,r1 */
148 #define IS_SUB01(x) (((x) & 0xffff) == 0x0510) /* subu r0,r1 */
149 #define IS_RTS(x) (((x) & 0xffff) == 0x00cf) /* jmp r15 */
151 #define IS_R1_ADJUSTER(x) \
152 (IS_ADDI1(x) || IS_SUBI1(x) || IS_ROTLI1(x) || IS_BSETI1(x) \
153 || IS_BCLRI1(x) || IS_RSUBI1(x) || IS_NOT1(x) \
154 || IS_IXH1(x) || IS_IXW1(x))
159 mcore_dump_insn (char *commnt
, CORE_ADDR pc
, int insn
)
163 printf_filtered ("MCORE: %s %08x %08x ",
164 commnt
, (unsigned int) pc
, (unsigned int) insn
);
165 TARGET_PRINT_INSN (pc
, &tm_print_insn_info
);
166 printf_filtered ("\n");
169 #define mcore_insn_debug(args) { if (mcore_debug) printf_filtered args; }
170 #else /* !MCORE_DEBUG */
171 #define mcore_dump_insn(a,b,c) {}
172 #define mcore_insn_debug(args) {}
177 mcore_register_virtual_type (int regnum
)
179 if (regnum
< 0 || regnum
>= MCORE_NUM_REGS
)
180 internal_error (__FILE__
, __LINE__
,
181 "mcore_register_virtual_type: illegal register number %d",
184 return builtin_type_int
;
188 mcore_register_byte (int regnum
)
190 if (regnum
< 0 || regnum
>= MCORE_NUM_REGS
)
191 internal_error (__FILE__
, __LINE__
,
192 "mcore_register_byte: illegal register number %d",
195 return (regnum
* MCORE_REG_SIZE
);
199 mcore_register_size (int regnum
)
202 if (regnum
< 0 || regnum
>= MCORE_NUM_REGS
)
203 internal_error (__FILE__
, __LINE__
,
204 "mcore_register_size: illegal register number %d",
207 return MCORE_REG_SIZE
;
210 /* The registers of the Motorola MCore processors */
213 mcore_register_name (int regnum
)
216 static char *register_names
[] = {
217 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
218 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
219 "ar0", "ar1", "ar2", "ar3", "ar4", "ar5", "ar6", "ar7",
220 "ar8", "ar9", "ar10", "ar11", "ar12", "ar13", "ar14", "ar15",
221 "psr", "vbr", "epsr", "fpsr", "epc", "fpc", "ss0", "ss1",
222 "ss2", "ss3", "ss4", "gcr", "gsr", "cr13", "cr14", "cr15",
223 "cr16", "cr17", "cr18", "cr19", "cr20", "cr21", "cr22", "cr23",
224 "cr24", "cr25", "cr26", "cr27", "cr28", "cr29", "cr30", "cr31",
229 regnum
>= sizeof (register_names
) / sizeof (register_names
[0]))
230 internal_error (__FILE__
, __LINE__
,
231 "mcore_register_name: illegal register number %d",
234 return register_names
[regnum
];
237 /* Given the address at which to insert a breakpoint (BP_ADDR),
238 what will that breakpoint be?
240 For MCore, we have a breakpoint instruction. Since all MCore
241 instructions are 16 bits, this is all we need, regardless of
242 address. bpkt = 0x0000 */
244 const unsigned char *
245 mcore_breakpoint_from_pc (CORE_ADDR
* bp_addr
, int *bp_size
)
247 static char breakpoint
[] =
254 mcore_saved_pc_after_call (struct frame_info
*frame
)
256 return read_register (PR_REGNUM
);
259 /* This is currently handled by init_extra_frame_info. */
261 mcore_frame_init_saved_regs (struct frame_info
*frame
)
266 /* This is currently handled by mcore_push_arguments */
268 mcore_store_struct_return (CORE_ADDR addr
, CORE_ADDR sp
)
274 mcore_reg_struct_has_addr (int gcc_p
, struct type
*type
)
280 /* Helper function for several routines below. This funtion simply
281 sets up a fake, aka dummy, frame (not a _call_ dummy frame) that
282 we can analyze with mcore_analyze_prologue. */
284 static struct frame_info
*
285 analyze_dummy_frame (CORE_ADDR pc
, CORE_ADDR frame
)
287 static struct frame_info
*dummy
= NULL
;
291 dummy
= (struct frame_info
*) xmalloc (sizeof (struct frame_info
));
292 dummy
->saved_regs
= (CORE_ADDR
*) xmalloc (SIZEOF_FRAME_SAVED_REGS
);
294 (struct frame_extra_info
*) xmalloc (sizeof (struct frame_extra_info
));
300 dummy
->frame
= frame
;
301 dummy
->extra_info
->status
= 0;
302 dummy
->extra_info
->framesize
= 0;
303 memset (dummy
->saved_regs
, '\000', SIZEOF_FRAME_SAVED_REGS
);
304 mcore_analyze_prologue (dummy
, 0, 0);
308 /* Function prologues on the Motorola MCore processors consist of:
310 - adjustments to the stack pointer (r1 used as scratch register)
311 - store word/multiples that use r0 as the base address
312 - making a copy of r0 into another register (a "frame" pointer)
314 Note that the MCore really doesn't have a real frame pointer.
315 Instead, the compiler may copy the SP into a register (usually
316 r8) to act as an arg pointer. For our target-dependent purposes,
317 the frame info's "frame" member will be the beginning of the
318 frame. The SP could, in fact, point below this.
320 The prologue ends when an instruction fails to meet either of
321 the first two criteria or when an FP is made. We make a special
322 exception for gcc. When compiling unoptimized code, gcc will
323 setup stack slots. We need to make sure that we skip the filling
324 of these stack slots as much as possible. This is only done
325 when SKIP_PROLOGUE is set, so that it does not mess up
328 /* Analyze the prologue of frame FI to determine where registers are saved,
329 the end of the prologue, etc. Return the address of the first line
330 of "real" code (i.e., the end of the prologue). */
333 mcore_analyze_prologue (struct frame_info
*fi
, CORE_ADDR pc
, int skip_prologue
)
335 CORE_ADDR func_addr
, func_end
, addr
, stop
;
336 CORE_ADDR stack_size
;
339 int fp_regnum
= 0; /* dummy, valid when (flags & MY_FRAME_IN_FP) */
342 int register_offsets
[NUM_REGS
];
345 /* If provided, use the PC in the frame to look up the
346 start of this function. */
347 pc
= (fi
== NULL
? pc
: fi
->pc
);
349 /* Find the start of this function. */
350 status
= find_pc_partial_function (pc
, &name
, &func_addr
, &func_end
);
352 /* If the start of this function could not be found or if the debbuger
353 is stopped at the first instruction of the prologue, do nothing. */
357 /* If the debugger is entry function, give up. */
358 if (func_addr
== entry_point_address ())
361 fi
->extra_info
->status
|= NO_MORE_FRAMES
;
365 /* At the start of a function, our frame is in the stack pointer. */
366 flags
= MY_FRAME_IN_SP
;
368 /* Start decoding the prologue. We start by checking two special cases:
370 1. We're about to return
371 2. We're at the first insn of the prologue.
373 If we're about to return, our frame has already been deallocated.
374 If we are stopped at the first instruction of a prologue,
375 then our frame has not yet been set up. */
377 /* Get the first insn from memory (all MCore instructions are 16 bits) */
378 mcore_insn_debug (("MCORE: starting prologue decoding\n"));
379 insn
= get_insn (pc
);
380 mcore_dump_insn ("got 1: ", pc
, insn
);
382 /* Check for return. */
383 if (fi
!= NULL
&& IS_RTS (insn
))
385 mcore_insn_debug (("MCORE: got jmp r15"));
386 if (fi
->next
== NULL
)
387 fi
->frame
= read_sp ();
391 /* Check for first insn of prologue */
392 if (fi
!= NULL
&& fi
->pc
== func_addr
)
394 if (fi
->next
== NULL
)
395 fi
->frame
= read_sp ();
399 /* Figure out where to stop scanning */
400 stop
= (fi
? fi
->pc
: func_end
);
402 /* Don't walk off the end of the function */
403 stop
= (stop
> func_end
? func_end
: stop
);
405 /* REGISTER_OFFSETS will contain offsets, from the top of the frame
406 (NOT the frame pointer), for the various saved registers or -1
407 if the register is not saved. */
408 for (rn
= 0; rn
< NUM_REGS
; rn
++)
409 register_offsets
[rn
] = -1;
411 /* Analyze the prologue. Things we determine from analyzing the
413 * the size of the frame
414 * where saved registers are located (and which are saved)
416 mcore_insn_debug (("MCORE: Scanning prologue: func_addr=0x%x, stop=0x%x\n",
417 (unsigned int) func_addr
, (unsigned int) stop
));
420 for (addr
= func_addr
; addr
< stop
; addr
+= 2)
423 insn
= get_insn (addr
);
424 mcore_dump_insn ("got 2: ", addr
, insn
);
428 int offset
= 1 + ((insn
>> 4) & 0x1f);
429 mcore_insn_debug (("MCORE: got subi r0,%d; continuing\n", offset
));
433 else if (IS_STM (insn
))
435 /* Spill register(s) */
439 /* BIG WARNING! The MCore ABI does not restrict functions
440 to taking only one stack allocation. Therefore, when
441 we save a register, we record the offset of where it was
442 saved relative to the current framesize. This will
443 then give an offset from the SP upon entry to our
444 function. Remember, framesize is NOT constant until
445 we're done scanning the prologue. */
446 start_register
= (insn
& 0xf);
447 mcore_insn_debug (("MCORE: got stm r%d-r15,(r0)\n", start_register
));
449 for (rn
= start_register
, offset
= 0; rn
<= 15; rn
++, offset
+= 4)
451 register_offsets
[rn
] = framesize
- offset
;
452 mcore_insn_debug (("MCORE: r%d saved at 0x%x (offset %d)\n", rn
,
453 register_offsets
[rn
], offset
));
455 mcore_insn_debug (("MCORE: continuing\n"));
458 else if (IS_STWx0 (insn
))
460 /* Spill register: see note for IS_STM above. */
463 rn
= (insn
>> 8) & 0xf;
464 imm
= (insn
>> 4) & 0xf;
465 register_offsets
[rn
] = framesize
- (imm
<< 2);
466 mcore_insn_debug (("MCORE: r%d saved at offset 0x%x\n", rn
, register_offsets
[rn
]));
467 mcore_insn_debug (("MCORE: continuing\n"));
470 else if (IS_MOVx0 (insn
))
472 /* We have a frame pointer, so this prologue is over. Note
473 the register which is acting as the frame pointer. */
474 flags
|= MY_FRAME_IN_FP
;
475 flags
&= ~MY_FRAME_IN_SP
;
476 fp_regnum
= insn
& 0xf;
477 mcore_insn_debug (("MCORE: Found a frame pointer: r%d\n", fp_regnum
));
479 /* If we found an FP, we're at the end of the prologue. */
480 mcore_insn_debug (("MCORE: end of prologue\n"));
484 /* If we're decoding prologue, stop here. */
488 else if (IS_STWxy (insn
) && (flags
& MY_FRAME_IN_FP
) && ((insn
& 0xf) == fp_regnum
))
490 /* Special case. Skip over stack slot allocs, too. */
491 mcore_insn_debug (("MCORE: push arg onto stack.\n"));
494 else if (IS_LRW1 (insn
) || IS_MOVI1 (insn
)
495 || IS_BGENI1 (insn
) || IS_BMASKI1 (insn
))
501 mcore_insn_debug (("MCORE: looking at large frame\n"));
505 read_memory_integer ((addr
+ 2 + ((insn
& 0xff) << 2)) & 0xfffffffc, 4);
507 else if (IS_MOVI1 (insn
))
508 adjust
= (insn
>> 4) & 0x7f;
509 else if (IS_BGENI1 (insn
))
510 adjust
= 1 << ((insn
>> 4) & 0x1f);
511 else /* IS_BMASKI (insn) */
512 adjust
= (1 << (adjust
>> 4) & 0x1f) - 1;
514 mcore_insn_debug (("MCORE: base framesize=0x%x\n", adjust
));
516 /* May have zero or more insns which modify r1 */
517 mcore_insn_debug (("MCORE: looking for r1 adjusters...\n"));
519 insn2
= get_insn (addr
+ offset
);
520 while (IS_R1_ADJUSTER (insn2
))
524 imm
= (insn2
>> 4) & 0x1f;
525 mcore_dump_insn ("got 3: ", addr
+ offset
, insn
);
526 if (IS_ADDI1 (insn2
))
529 mcore_insn_debug (("MCORE: addi r1,%d\n", imm
+ 1));
531 else if (IS_SUBI1 (insn2
))
534 mcore_insn_debug (("MCORE: subi r1,%d\n", imm
+ 1));
536 else if (IS_RSUBI1 (insn2
))
538 adjust
= imm
- adjust
;
539 mcore_insn_debug (("MCORE: rsubi r1,%d\n", imm
+ 1));
541 else if (IS_NOT1 (insn2
))
544 mcore_insn_debug (("MCORE: not r1\n"));
546 else if (IS_ROTLI1 (insn2
))
549 mcore_insn_debug (("MCORE: rotli r1,%d\n", imm
+ 1));
551 else if (IS_BSETI1 (insn2
))
553 adjust
|= (1 << imm
);
554 mcore_insn_debug (("MCORE: bseti r1,%d\n", imm
));
556 else if (IS_BCLRI1 (insn2
))
558 adjust
&= ~(1 << imm
);
559 mcore_insn_debug (("MCORE: bclri r1,%d\n", imm
));
561 else if (IS_IXH1 (insn2
))
564 mcore_insn_debug (("MCORE: ix.h r1,r1\n"));
566 else if (IS_IXW1 (insn2
))
569 mcore_insn_debug (("MCORE: ix.w r1,r1\n"));
573 insn2
= get_insn (addr
+ offset
);
576 mcore_insn_debug (("MCORE: done looking for r1 adjusters\n"));
578 /* If the next insn adjusts the stack pointer, we keep everything;
579 if not, we scrap it and we've found the end of the prologue. */
580 if (IS_SUB01 (insn2
))
584 mcore_insn_debug (("MCORE: found stack adjustment of 0x%x bytes.\n", adjust
));
585 mcore_insn_debug (("MCORE: skipping to new address 0x%x\n", addr
));
586 mcore_insn_debug (("MCORE: continuing\n"));
590 /* None of these instructions are prologue, so don't touch
592 mcore_insn_debug (("MCORE: no subu r1,r0, NOT altering framesize.\n"));
596 /* This is not a prologue insn, so stop here. */
597 mcore_insn_debug (("MCORE: insn is not a prologue insn -- ending scan\n"));
601 mcore_insn_debug (("MCORE: done analyzing prologue\n"));
602 mcore_insn_debug (("MCORE: prologue end = 0x%x\n", addr
));
604 /* Save everything we have learned about this frame into FI. */
607 fi
->extra_info
->framesize
= framesize
;
608 fi
->extra_info
->fp_regnum
= fp_regnum
;
609 fi
->extra_info
->status
= flags
;
611 /* Fix the frame pointer. When gcc uses r8 as a frame pointer,
612 it is really an arg ptr. We adjust fi->frame to be a "real"
614 if (fi
->next
== NULL
)
616 if (fi
->extra_info
->status
& MY_FRAME_IN_SP
)
617 fi
->frame
= read_sp () + framesize
;
619 fi
->frame
= read_register (fp_regnum
) + framesize
;
622 /* Note where saved registers are stored. The offsets in REGISTER_OFFSETS
623 are computed relative to the top of the frame. */
624 for (rn
= 0; rn
< NUM_REGS
; rn
++)
626 if (register_offsets
[rn
] >= 0)
628 fi
->saved_regs
[rn
] = fi
->frame
- register_offsets
[rn
];
629 mcore_insn_debug (("Saved register %s stored at 0x%08x, value=0x%08x\n",
630 mcore_register_names
[rn
], fi
->saved_regs
[rn
],
631 read_memory_integer (fi
->saved_regs
[rn
], 4)));
636 /* Return addr of first non-prologue insn. */
640 /* Given a GDB frame, determine the address of the calling function's frame.
641 This will be used to create a new GDB frame struct, and then
642 INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame. */
645 mcore_frame_chain (struct frame_info
* fi
)
647 struct frame_info
*dummy
;
648 CORE_ADDR callers_addr
;
650 /* Analyze the prologue of this function. */
651 if (fi
->extra_info
->status
== 0)
652 mcore_analyze_prologue (fi
, 0, 0);
654 /* If mcore_analyze_prologue set NO_MORE_FRAMES, quit now. */
655 if (fi
->extra_info
->status
& NO_MORE_FRAMES
)
658 /* Now that we've analyzed our prologue, we can start to ask
659 for information about our caller. The easiest way to do
660 this is to analyze our caller's prologue.
662 If our caller has a frame pointer, then we need to find
663 the value of that register upon entry to our frame.
664 This value is either in fi->saved_regs[rn] if it's saved,
665 or it's still in a register.
667 If our caller does not have a frame pointer, then his frame base
668 is <our base> + -<caller's frame size>. */
669 dummy
= analyze_dummy_frame (FRAME_SAVED_PC (fi
), fi
->frame
);
671 if (dummy
->extra_info
->status
& MY_FRAME_IN_FP
)
673 int fp
= dummy
->extra_info
->fp_regnum
;
675 /* Our caller has a frame pointer. */
676 if (fi
->saved_regs
[fp
] != 0)
678 /* The "FP" was saved on the stack. Don't forget to adjust
679 the "FP" with the framesize to get a real FP. */
680 callers_addr
= read_memory_integer (fi
->saved_regs
[fp
], REGISTER_SIZE
)
681 + dummy
->extra_info
->framesize
;
685 /* It's still in the register. Don't forget to adjust
686 the "FP" with the framesize to get a real FP. */
687 callers_addr
= read_register (fp
) + dummy
->extra_info
->framesize
;
692 /* Our caller does not have a frame pointer. */
693 callers_addr
= fi
->frame
+ dummy
->extra_info
->framesize
;
699 /* Skip the prologue of the function at PC. */
702 mcore_skip_prologue (CORE_ADDR pc
)
704 CORE_ADDR func_addr
, func_end
;
705 struct symtab_and_line sal
;
707 /* If we have line debugging information, then the end of the
708 prologue should be the first assembly instruction of the first
710 if (find_pc_partial_function (pc
, NULL
, &func_addr
, &func_end
))
712 sal
= find_pc_line (func_addr
, 0);
713 if (sal
.end
&& sal
.end
< func_end
)
717 return mcore_analyze_prologue (NULL
, pc
, 1);
720 /* Return the address at which function arguments are offset. */
722 mcore_frame_args_address (struct frame_info
* fi
)
724 return fi
->frame
- fi
->extra_info
->framesize
;
728 mcore_frame_locals_address (struct frame_info
* fi
)
730 return fi
->frame
- fi
->extra_info
->framesize
;
733 /* Return the frame pointer in use at address PC. */
736 mcore_virtual_frame_pointer (CORE_ADDR pc
, int *reg
, LONGEST
*offset
)
738 struct frame_info
*dummy
= analyze_dummy_frame (pc
, 0);
739 if (dummy
->extra_info
->status
& MY_FRAME_IN_SP
)
746 *reg
= dummy
->extra_info
->fp_regnum
;
751 /* Find the value of register REGNUM in frame FI. */
754 mcore_find_callers_reg (struct frame_info
*fi
, int regnum
)
756 for (; fi
!= NULL
; fi
= fi
->next
)
758 if (PC_IN_CALL_DUMMY (fi
->pc
, fi
->frame
, fi
->frame
))
759 return generic_read_register_dummy (fi
->pc
, fi
->frame
, regnum
);
760 else if (fi
->saved_regs
[regnum
] != 0)
761 return read_memory_integer (fi
->saved_regs
[regnum
],
765 return read_register (regnum
);
768 /* Find the saved pc in frame FI. */
771 mcore_frame_saved_pc (struct frame_info
* fi
)
774 if (PC_IN_CALL_DUMMY (fi
->pc
, fi
->frame
, fi
->frame
))
775 return generic_read_register_dummy (fi
->pc
, fi
->frame
, PC_REGNUM
);
777 return mcore_find_callers_reg (fi
, PR_REGNUM
);
780 /* INFERIOR FUNCTION CALLS */
782 /* This routine gets called when either the user uses the "return"
783 command, or the call dummy breakpoint gets hit. */
786 mcore_pop_frame (void)
789 struct frame_info
*fi
= get_current_frame ();
791 if (PC_IN_CALL_DUMMY (fi
->pc
, fi
->frame
, fi
->frame
))
792 generic_pop_dummy_frame ();
795 /* Write out the PC we saved. */
796 write_register (PC_REGNUM
, FRAME_SAVED_PC (fi
));
798 /* Restore any saved registers. */
799 for (rn
= 0; rn
< NUM_REGS
; rn
++)
801 if (fi
->saved_regs
[rn
] != 0)
805 value
= read_memory_unsigned_integer (fi
->saved_regs
[rn
],
807 write_register (rn
, value
);
811 /* Actually cut back the stack. */
812 write_register (SP_REGNUM
, FRAME_FP (fi
));
815 /* Finally, throw away any cached frame information. */
816 flush_cached_frames ();
819 /* Setup arguments and PR for a call to the target. First six arguments
820 go in FIRST_ARGREG -> LAST_ARGREG, subsequent args go on to the stack.
822 * Types with lengths greater than REGISTER_SIZE may not be split
823 between registers and the stack, and they must start in an even-numbered
824 register. Subsequent args will go onto the stack.
826 * Structs may be split between registers and stack, left-aligned.
828 * If the function returns a struct which will not fit into registers (it's
829 more than eight bytes), we must allocate for that, too. Gdb will tell
830 us where this buffer is (STRUCT_ADDR), and we simply place it into
831 FIRST_ARGREG, since the MCORE treats struct returns (of less than eight
832 bytes) as hidden first arguments. */
835 mcore_push_arguments (int nargs
, struct value
**args
, CORE_ADDR sp
,
836 int struct_return
, CORE_ADDR struct_addr
)
848 stack_args
= (struct stack_arg
*) alloca (nargs
* sizeof (struct stack_arg
));
850 argreg
= FIRST_ARGREG
;
852 /* Align the stack. This is mostly a nop, but not always. It will be needed
853 if we call a function which has argument overflow. */
856 /* If this function returns a struct which does not fit in the
857 return registers, we must pass a buffer to the function
858 which it can use to save the return value. */
860 write_register (argreg
++, struct_addr
);
862 /* FIXME: what about unions? */
863 for (argnum
= 0; argnum
< nargs
; argnum
++)
865 char *val
= (char *) VALUE_CONTENTS (args
[argnum
]);
866 int len
= TYPE_LENGTH (VALUE_TYPE (args
[argnum
]));
867 struct type
*type
= VALUE_TYPE (args
[argnum
]);
870 mcore_insn_debug (("MCORE PUSH: argreg=%d; len=%d; %s\n",
871 argreg
, len
, TYPE_CODE (type
) == TYPE_CODE_STRUCT
? "struct" : "not struct"));
872 /* Arguments larger than a register must start in an even
873 numbered register. */
876 if (TYPE_CODE (type
) != TYPE_CODE_STRUCT
&& len
> REGISTER_SIZE
&& argreg
% 2)
878 mcore_insn_debug (("MCORE PUSH: %d > REGISTER_SIZE: and %s is not even\n",
879 len
, mcore_register_names
[argreg
]));
883 if ((argreg
<= LAST_ARGREG
&& len
<= (LAST_ARGREG
- argreg
+ 1) * REGISTER_SIZE
)
884 || (TYPE_CODE (type
) == TYPE_CODE_STRUCT
))
886 /* Something that will fit entirely into registers (or a struct
887 which may be split between registers and stack). */
888 mcore_insn_debug (("MCORE PUSH: arg %d going into regs\n", argnum
));
890 if (TYPE_CODE (type
) == TYPE_CODE_STRUCT
&& olen
< REGISTER_SIZE
)
892 /* Small structs must be right aligned within the register,
893 the most significant bits are undefined. */
894 write_register (argreg
, extract_unsigned_integer (val
, len
));
899 while (len
> 0 && argreg
<= LAST_ARGREG
)
901 write_register (argreg
, extract_unsigned_integer (val
, REGISTER_SIZE
));
903 val
+= REGISTER_SIZE
;
904 len
-= REGISTER_SIZE
;
907 /* Any remainder for the stack is noted below... */
909 else if (TYPE_CODE (VALUE_TYPE (args
[argnum
])) != TYPE_CODE_STRUCT
910 && len
> REGISTER_SIZE
)
912 /* All subsequent args go onto the stack. */
913 mcore_insn_debug (("MCORE PUSH: does not fit into regs, going onto stack\n"));
914 argnum
= LAST_ARGREG
+ 1;
919 /* Note that this must be saved onto the stack */
920 mcore_insn_debug (("MCORE PUSH: adding arg %d to stack\n", argnum
));
921 stack_args
[nstack_args
].val
= val
;
922 stack_args
[nstack_args
].len
= len
;
928 /* We're done with registers and stack allocation. Now do the actual
930 while (nstack_args
--)
932 sp
-= stack_args
[nstack_args
].len
;
933 write_memory (sp
, stack_args
[nstack_args
].val
, stack_args
[nstack_args
].len
);
936 /* Return adjusted stack pointer. */
940 /* Store the return address for the call dummy. For MCore, we've
941 opted to use generic call dummies, so we simply store the
942 CALL_DUMMY_ADDRESS into the PR register (r15). */
945 mcore_push_return_address (CORE_ADDR pc
, CORE_ADDR sp
)
947 write_register (PR_REGNUM
, CALL_DUMMY_ADDRESS ());
951 /* Setting/getting return values from functions.
953 The Motorola MCore processors use r2/r3 to return anything
954 not larger than 32 bits. Everything else goes into a caller-
955 supplied buffer, which is passed in via a hidden first
958 For gdb, this leaves us two routes, based on what
959 USE_STRUCT_CONVENTION (mcore_use_struct_convention) returns.
960 If this macro returns 1, gdb will call STORE_STRUCT_RETURN and
961 EXTRACT_STRUCT_VALUE_ADDRESS.
963 If USE_STRUCT_CONVENTION retruns 0, then gdb uses STORE_RETURN_VALUE
964 and EXTRACT_RETURN_VALUE to store/fetch the functions return value. */
966 /* Should we use EXTRACT_STRUCT_VALUE_ADDRESS instead of
967 EXTRACT_RETURN_VALUE? GCC_P is true if compiled with gcc
968 and TYPE is the type (which is known to be struct, union or array). */
971 mcore_use_struct_convention (int gcc_p
, struct type
*type
)
973 return (TYPE_LENGTH (type
) > 8);
976 /* Where is the return value saved? For MCore, a pointer to
977 this buffer was passed as a hidden first argument, so
978 just return that address. */
981 mcore_extract_struct_value_address (char *regbuf
)
983 return extract_address (regbuf
+ REGISTER_BYTE (FIRST_ARGREG
), REGISTER_SIZE
);
986 /* Given a function which returns a value of type TYPE, extract the
987 the function's return value and place the result into VALBUF.
988 REGBUF is the register contents of the target. */
991 mcore_extract_return_value (struct type
*type
, char *regbuf
, char *valbuf
)
993 /* Copy the return value (starting) in RETVAL_REGNUM to VALBUF. */
994 /* Only getting the first byte! if len = 1, we need the last byte of
995 the register, not the first. */
996 memcpy (valbuf
, regbuf
+ REGISTER_BYTE (RETVAL_REGNUM
) +
997 (TYPE_LENGTH (type
) < 4 ? 4 - TYPE_LENGTH (type
) : 0), TYPE_LENGTH (type
));
1000 /* Store the return value in VALBUF (of type TYPE) where the caller
1003 Values less than 32 bits are stored in r2, right justified and
1004 sign or zero extended.
1006 Values between 32 and 64 bits are stored in r2 (most
1007 significant word) and r3 (least significant word, left justified).
1008 Note that this includes structures of less than eight bytes, too. */
1011 mcore_store_return_value (struct type
*type
, char *valbuf
)
1018 value_size
= TYPE_LENGTH (type
);
1020 /* Return value fits into registers. */
1021 return_size
= (value_size
+ REGISTER_SIZE
- 1) & ~(REGISTER_SIZE
- 1);
1022 offset
= REGISTER_BYTE (RETVAL_REGNUM
) + (return_size
- value_size
);
1023 zeros
= alloca (return_size
);
1024 memset (zeros
, 0, return_size
);
1026 write_register_bytes (REGISTER_BYTE (RETVAL_REGNUM
), zeros
, return_size
);
1027 write_register_bytes (offset
, valbuf
, value_size
);
1030 /* Initialize our target-dependent "stuff" for this newly created frame.
1032 This includes allocating space for saved registers and analyzing
1033 the prologue of this frame. */
1036 mcore_init_extra_frame_info (int fromleaf
, struct frame_info
*fi
)
1039 fi
->pc
= FRAME_SAVED_PC (fi
->next
);
1041 frame_saved_regs_zalloc (fi
);
1043 fi
->extra_info
= (struct frame_extra_info
*)
1044 frame_obstack_alloc (sizeof (struct frame_extra_info
));
1045 fi
->extra_info
->status
= 0;
1046 fi
->extra_info
->framesize
= 0;
1048 if (PC_IN_CALL_DUMMY (fi
->pc
, fi
->frame
, fi
->frame
))
1050 /* We need to setup fi->frame here because run_stack_dummy gets it wrong
1051 by assuming it's always FP. */
1052 fi
->frame
= generic_read_register_dummy (fi
->pc
, fi
->frame
, SP_REGNUM
);
1055 mcore_analyze_prologue (fi
, 0, 0);
1058 /* Get an insturction from memory. */
1061 get_insn (CORE_ADDR pc
)
1064 int status
= read_memory_nobpt (pc
, buf
, 2);
1068 return extract_unsigned_integer (buf
, 2);
1071 static struct gdbarch
*
1072 mcore_gdbarch_init (struct gdbarch_info info
, struct gdbarch_list
*arches
)
1074 static LONGEST call_dummy_words
[7] = { };
1075 struct gdbarch_tdep
*tdep
= NULL
;
1076 struct gdbarch
*gdbarch
;
1078 /* find a candidate among the list of pre-declared architectures. */
1079 arches
= gdbarch_list_lookup_by_info (arches
, &info
);
1081 return (arches
->gdbarch
);
1083 gdbarch
= gdbarch_alloc (&info
, 0);
1087 /* All registers are 32 bits */
1088 set_gdbarch_register_size (gdbarch
, MCORE_REG_SIZE
);
1089 set_gdbarch_max_register_raw_size (gdbarch
, MCORE_REG_SIZE
);
1090 set_gdbarch_max_register_virtual_size (gdbarch
, MCORE_REG_SIZE
);
1091 set_gdbarch_register_name (gdbarch
, mcore_register_name
);
1092 set_gdbarch_register_virtual_type (gdbarch
, mcore_register_virtual_type
);
1093 set_gdbarch_register_virtual_size (gdbarch
, mcore_register_size
);
1094 set_gdbarch_register_raw_size (gdbarch
, mcore_register_size
);
1095 set_gdbarch_register_byte (gdbarch
, mcore_register_byte
);
1096 set_gdbarch_register_bytes (gdbarch
, MCORE_REG_SIZE
* MCORE_NUM_REGS
);
1097 set_gdbarch_num_regs (gdbarch
, MCORE_NUM_REGS
);
1098 set_gdbarch_pc_regnum (gdbarch
, 64);
1099 set_gdbarch_sp_regnum (gdbarch
, 0);
1100 set_gdbarch_fp_regnum (gdbarch
, 0);
1101 set_gdbarch_get_saved_register (gdbarch
, generic_get_saved_register
);
1105 set_gdbarch_call_dummy_p (gdbarch
, 1);
1106 set_gdbarch_use_generic_dummy_frames (gdbarch
, 1);
1107 set_gdbarch_call_dummy_words (gdbarch
, call_dummy_words
);
1108 set_gdbarch_sizeof_call_dummy_words (gdbarch
, 0);
1109 set_gdbarch_call_dummy_start_offset (gdbarch
, 0);
1110 set_gdbarch_call_dummy_breakpoint_offset_p (gdbarch
, 1);
1111 set_gdbarch_call_dummy_breakpoint_offset (gdbarch
, 0);
1112 set_gdbarch_call_dummy_location (gdbarch
, AT_ENTRY_POINT
);
1113 set_gdbarch_fix_call_dummy (gdbarch
, generic_fix_call_dummy
);
1114 set_gdbarch_call_dummy_address (gdbarch
, entry_point_address
);
1115 set_gdbarch_save_dummy_frame_tos (gdbarch
, generic_save_dummy_frame_tos
);
1116 set_gdbarch_pc_in_call_dummy (gdbarch
, generic_pc_in_call_dummy
);
1117 set_gdbarch_call_dummy_stack_adjust_p (gdbarch
, 0);
1118 set_gdbarch_saved_pc_after_call (gdbarch
, mcore_saved_pc_after_call
);
1119 set_gdbarch_function_start_offset (gdbarch
, 0);
1120 set_gdbarch_decr_pc_after_break (gdbarch
, 0);
1121 set_gdbarch_breakpoint_from_pc (gdbarch
, mcore_breakpoint_from_pc
);
1122 set_gdbarch_push_return_address (gdbarch
, mcore_push_return_address
);
1123 set_gdbarch_push_dummy_frame (gdbarch
, generic_push_dummy_frame
);
1124 set_gdbarch_push_arguments (gdbarch
, mcore_push_arguments
);
1125 set_gdbarch_call_dummy_length (gdbarch
, 0);
1129 set_gdbarch_init_extra_frame_info (gdbarch
, mcore_init_extra_frame_info
);
1130 set_gdbarch_frame_chain (gdbarch
, mcore_frame_chain
);
1131 set_gdbarch_frame_chain_valid (gdbarch
, generic_func_frame_chain_valid
);
1132 set_gdbarch_frame_init_saved_regs (gdbarch
, mcore_frame_init_saved_regs
);
1133 set_gdbarch_frame_saved_pc (gdbarch
, mcore_frame_saved_pc
);
1134 set_gdbarch_store_return_value (gdbarch
, mcore_store_return_value
);
1135 set_gdbarch_deprecated_extract_return_value (gdbarch
,
1136 mcore_extract_return_value
);
1137 set_gdbarch_store_struct_return (gdbarch
, mcore_store_struct_return
);
1138 set_gdbarch_deprecated_extract_struct_value_address (gdbarch
,
1139 mcore_extract_struct_value_address
);
1140 set_gdbarch_skip_prologue (gdbarch
, mcore_skip_prologue
);
1141 set_gdbarch_frame_args_skip (gdbarch
, 0);
1142 set_gdbarch_frame_args_address (gdbarch
, mcore_frame_args_address
);
1143 set_gdbarch_frame_locals_address (gdbarch
, mcore_frame_locals_address
);
1144 set_gdbarch_frame_num_args (gdbarch
, frame_num_args_unknown
);
1145 set_gdbarch_pop_frame (gdbarch
, mcore_pop_frame
);
1146 set_gdbarch_virtual_frame_pointer (gdbarch
, mcore_virtual_frame_pointer
);
1150 /* Stack grows down. */
1151 set_gdbarch_inner_than (gdbarch
, core_addr_lessthan
);
1152 set_gdbarch_use_struct_convention (gdbarch
, mcore_use_struct_convention
);
1153 set_gdbarch_believe_pcc_promotion (gdbarch
, 1);
1154 /* MCore will never pass a sturcture by reference. It will always be split
1155 between registers and stack. */
1156 set_gdbarch_reg_struct_has_addr (gdbarch
, mcore_reg_struct_has_addr
);
1162 mcore_dump_tdep (struct gdbarch
*current_gdbarch
, struct ui_file
*file
)
1168 _initialize_mcore_tdep (void)
1170 extern int print_insn_mcore (bfd_vma
, disassemble_info
*);
1171 gdbarch_register (bfd_arch_mcore
, mcore_gdbarch_init
, mcore_dump_tdep
);
1172 tm_print_insn
= print_insn_mcore
;
1175 add_show_from_set (add_set_cmd ("mcoredebug", no_class
,
1176 var_boolean
, (char *) &mcore_debug
,
1177 "Set mcore debugging.\n", &setlist
),