1 /* Intel 386 target-dependent stuff.
2 Copyright (C) 1988, 1989, 1991, 1994, 1995, 1996, 1998
3 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 #include "gdb_string.h"
28 #include "floatformat.h"
33 static long i386_get_frame_setup PARAMS ((CORE_ADDR));
35 static void i386_follow_jump PARAMS ((void));
37 static void codestream_read PARAMS ((unsigned char *, int));
39 static void codestream_seek PARAMS ((CORE_ADDR));
41 static unsigned char codestream_fill PARAMS ((int));
43 CORE_ADDR skip_trampoline_code PARAMS ((CORE_ADDR, char *));
45 static int gdb_print_insn_i386 (bfd_vma, disassemble_info *);
47 void _initialize_i386_tdep PARAMS ((void));
49 /* i386_register_byte[i] is the offset into the register file of the
50 start of register number i. We initialize this from
51 i386_register_raw_size. */
52 int i386_register_byte[MAX_NUM_REGS];
54 /* i386_register_raw_size[i] is the number of bytes of storage in
55 GDB's register array occupied by register i. */
56 int i386_register_raw_size[MAX_NUM_REGS] = {
70 /* i386_register_virtual_size[i] is the size in bytes of the virtual
71 type of register i. */
72 int i386_register_virtual_size[MAX_NUM_REGS];
75 /* This is the variable the is set with "set disassembly-flavor",
76 and its legitimate values. */
77 static char att_flavor[] = "att";
78 static char intel_flavor[] = "intel";
79 static char *valid_flavors[] =
85 static char *disassembly_flavor = att_flavor;
87 static void i386_print_register PARAMS ((char *, int, int));
89 /* This is used to keep the bfd arch_info in sync with the disassembly flavor. */
90 static void set_disassembly_flavor_sfunc PARAMS ((char *, int, struct cmd_list_element *));
91 static void set_disassembly_flavor PARAMS ((void));
93 /* Stdio style buffering was used to minimize calls to ptrace, but this
94 buffering did not take into account that the code section being accessed
95 may not be an even number of buffers long (even if the buffer is only
96 sizeof(int) long). In cases where the code section size happened to
97 be a non-integral number of buffers long, attempting to read the last
98 buffer would fail. Simply using target_read_memory and ignoring errors,
99 rather than read_memory, is not the correct solution, since legitimate
100 access errors would then be totally ignored. To properly handle this
101 situation and continue to use buffering would require that this code
102 be able to determine the minimum code section size granularity (not the
103 alignment of the section itself, since the actual failing case that
104 pointed out this problem had a section alignment of 4 but was not a
105 multiple of 4 bytes long), on a target by target basis, and then
106 adjust it's buffer size accordingly. This is messy, but potentially
107 feasible. It probably needs the bfd library's help and support. For
108 now, the buffer size is set to 1. (FIXME -fnf) */
110 #define CODESTREAM_BUFSIZ 1 /* Was sizeof(int), see note above. */
111 static CORE_ADDR codestream_next_addr;
112 static CORE_ADDR codestream_addr;
113 static unsigned char codestream_buf[CODESTREAM_BUFSIZ];
114 static int codestream_off;
115 static int codestream_cnt;
117 #define codestream_tell() (codestream_addr + codestream_off)
118 #define codestream_peek() (codestream_cnt == 0 ? \
119 codestream_fill(1): codestream_buf[codestream_off])
120 #define codestream_get() (codestream_cnt-- == 0 ? \
121 codestream_fill(0) : codestream_buf[codestream_off++])
124 codestream_fill (peek_flag)
127 codestream_addr = codestream_next_addr;
128 codestream_next_addr += CODESTREAM_BUFSIZ;
130 codestream_cnt = CODESTREAM_BUFSIZ;
131 read_memory (codestream_addr, (char *) codestream_buf, CODESTREAM_BUFSIZ);
134 return (codestream_peek ());
136 return (codestream_get ());
140 codestream_seek (place)
143 codestream_next_addr = place / CODESTREAM_BUFSIZ;
144 codestream_next_addr *= CODESTREAM_BUFSIZ;
147 while (codestream_tell () != place)
152 codestream_read (buf, count)
159 for (i = 0; i < count; i++)
160 *p++ = codestream_get ();
163 /* next instruction is a jump, move to target */
168 unsigned char buf[4];
174 pos = codestream_tell ();
177 if (codestream_peek () == 0x66)
183 switch (codestream_get ())
186 /* relative jump: if data16 == 0, disp32, else disp16 */
189 codestream_read (buf, 2);
190 delta = extract_signed_integer (buf, 2);
192 /* include size of jmp inst (including the 0x66 prefix). */
197 codestream_read (buf, 4);
198 delta = extract_signed_integer (buf, 4);
204 /* relative jump, disp8 (ignore data16) */
205 codestream_read (buf, 1);
206 /* Sign-extend it. */
207 delta = extract_signed_integer (buf, 1);
212 codestream_seek (pos);
216 * find & return amound a local space allocated, and advance codestream to
217 * first register push (if any)
219 * if entry sequence doesn't make sense, return -1, and leave
220 * codestream pointer random
224 i386_get_frame_setup (pc)
229 codestream_seek (pc);
233 op = codestream_get ();
235 if (op == 0x58) /* popl %eax */
238 * this function must start with
241 * xchgl %eax, (%esp) 0x87 0x04 0x24
242 * or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00
244 * (the system 5 compiler puts out the second xchg
245 * inst, and the assembler doesn't try to optimize it,
246 * so the 'sib' form gets generated)
248 * this sequence is used to get the address of the return
249 * buffer for a function that returns a structure
252 unsigned char buf[4];
253 static unsigned char proto1[3] =
255 static unsigned char proto2[4] =
256 {0x87, 0x44, 0x24, 0x00};
257 pos = codestream_tell ();
258 codestream_read (buf, 4);
259 if (memcmp (buf, proto1, 3) == 0)
261 else if (memcmp (buf, proto2, 4) == 0)
264 codestream_seek (pos);
265 op = codestream_get (); /* update next opcode */
268 if (op == 0x68 || op == 0x6a)
271 * this function may start with
281 unsigned char buf[8];
283 /* Skip past the pushl instruction; it has either a one-byte
284 or a four-byte operand, depending on the opcode. */
285 pos = codestream_tell ();
290 codestream_seek (pos);
292 /* Read the following 8 bytes, which should be "call _probe" (6 bytes)
293 followed by "addl $4,%esp" (2 bytes). */
294 codestream_read (buf, sizeof (buf));
295 if (buf[0] == 0xe8 && buf[6] == 0xc4 && buf[7] == 0x4)
297 codestream_seek (pos);
298 op = codestream_get (); /* update next opcode */
301 if (op == 0x55) /* pushl %ebp */
303 /* check for movl %esp, %ebp - can be written two ways */
304 switch (codestream_get ())
307 if (codestream_get () != 0xec)
311 if (codestream_get () != 0xe5)
317 /* check for stack adjustment
321 * note: you can't subtract a 16 bit immediate
322 * from a 32 bit reg, so we don't have to worry
323 * about a data16 prefix
325 op = codestream_peek ();
328 /* subl with 8 bit immed */
330 if (codestream_get () != 0xec)
331 /* Some instruction starting with 0x83 other than subl. */
333 codestream_seek (codestream_tell () - 2);
336 /* subl with signed byte immediate
337 * (though it wouldn't make sense to be negative)
339 return (codestream_get ());
344 /* Maybe it is subl with 32 bit immedediate. */
346 if (codestream_get () != 0xec)
347 /* Some instruction starting with 0x81 other than subl. */
349 codestream_seek (codestream_tell () - 2);
352 /* It is subl with 32 bit immediate. */
353 codestream_read ((unsigned char *) buf, 4);
354 return extract_signed_integer (buf, 4);
364 /* enter instruction: arg is 16 bit unsigned immed */
365 codestream_read ((unsigned char *) buf, 2);
366 codestream_get (); /* flush final byte of enter instruction */
367 return extract_unsigned_integer (buf, 2);
372 /* Return number of args passed to a frame.
373 Can return -1, meaning no way to tell. */
376 i386_frame_num_args (fi)
377 struct frame_info *fi;
382 /* This loses because not only might the compiler not be popping the
383 args right after the function call, it might be popping args from both
384 this call and a previous one, and we would say there are more args
385 than there really are. */
389 struct frame_info *pfi;
391 /* on the 386, the instruction following the call could be:
393 addl $imm, %esp - imm/4 args; imm may be 8 or 32 bits
394 anything else - zero args */
398 frameless = FRAMELESS_FUNCTION_INVOCATION (fi);
400 /* In the absence of a frame pointer, GDB doesn't get correct values
401 for nameless arguments. Return -1, so it doesn't print any
402 nameless arguments. */
405 pfi = get_prev_frame (fi);
408 /* Note: this can happen if we are looking at the frame for
409 main, because FRAME_CHAIN_VALID won't let us go into
410 start. If we have debugging symbols, that's not really
411 a big deal; it just means it will only show as many arguments
412 to main as are declared. */
418 op = read_memory_integer (retpc, 1);
424 op = read_memory_integer (retpc + 1, 1);
426 /* addl $<signed imm 8 bits>, %esp */
427 return (read_memory_integer (retpc + 2, 1) & 0xff) / 4;
432 { /* add with 32 bit immediate */
433 op = read_memory_integer (retpc + 1, 1);
435 /* addl $<imm 32>, %esp */
436 return read_memory_integer (retpc + 2, 4) / 4;
449 * parse the first few instructions of the function to see
450 * what registers were stored.
452 * We handle these cases:
454 * The startup sequence can be at the start of the function,
455 * or the function can start with a branch to startup code at the end.
457 * %ebp can be set up with either the 'enter' instruction, or
458 * 'pushl %ebp, movl %esp, %ebp' (enter is too slow to be useful,
459 * but was once used in the sys5 compiler)
461 * Local space is allocated just below the saved %ebp by either the
462 * 'enter' instruction, or by 'subl $<size>, %esp'. 'enter' has
463 * a 16 bit unsigned argument for space to allocate, and the
464 * 'addl' instruction could have either a signed byte, or
467 * Next, the registers used by this function are pushed. In
468 * the sys5 compiler they will always be in the order: %edi, %esi, %ebx
469 * (and sometimes a harmless bug causes it to also save but not restore %eax);
470 * however, the code below is willing to see the pushes in any order,
471 * and will handle up to 8 of them.
473 * If the setup sequence is at the end of the function, then the
474 * next instruction will be a branch back to the start.
478 i386_frame_find_saved_regs (fip, fsrp)
479 struct frame_info *fip;
480 struct frame_saved_regs *fsrp;
484 CORE_ADDR dummy_bottom;
489 memset (fsrp, 0, sizeof *fsrp);
491 /* if frame is the end of a dummy, compute where the
494 dummy_bottom = fip->frame - 4 - REGISTER_BYTES - CALL_DUMMY_LENGTH;
496 /* check if the PC is in the stack, in a dummy frame */
497 if (dummy_bottom <= fip->pc && fip->pc <= fip->frame)
499 /* all regs were saved by push_call_dummy () */
501 for (i = 0; i < NUM_REGS; i++)
503 adr -= REGISTER_RAW_SIZE (i);
509 pc = get_pc_function_start (fip->pc);
511 locals = i386_get_frame_setup (pc);
515 adr = fip->frame - 4 - locals;
516 for (i = 0; i < 8; i++)
518 op = codestream_get ();
519 if (op < 0x50 || op > 0x57)
521 #ifdef I386_REGNO_TO_SYMMETRY
522 /* Dynix uses different internal numbering. Ick. */
523 fsrp->regs[I386_REGNO_TO_SYMMETRY (op - 0x50)] = adr;
525 fsrp->regs[op - 0x50] = adr;
531 fsrp->regs[PC_REGNUM] = fip->frame + 4;
532 fsrp->regs[FP_REGNUM] = fip->frame;
535 /* return pc of first real instruction */
538 i386_skip_prologue (pc)
543 static unsigned char pic_pat[6] =
544 {0xe8, 0, 0, 0, 0, /* call 0x0 */
545 0x5b, /* popl %ebx */
549 if (i386_get_frame_setup (pc) < 0)
552 /* found valid frame setup - codestream now points to
553 * start of push instructions for saving registers
556 /* skip over register saves */
557 for (i = 0; i < 8; i++)
559 op = codestream_peek ();
560 /* break if not pushl inst */
561 if (op < 0x50 || op > 0x57)
566 /* The native cc on SVR4 in -K PIC mode inserts the following code to get
567 the address of the global offset table (GOT) into register %ebx.
570 movl %ebx,x(%ebp) (optional)
572 This code is with the rest of the prologue (at the end of the
573 function), so we have to skip it to get to the first real
574 instruction at the start of the function. */
576 pos = codestream_tell ();
577 for (i = 0; i < 6; i++)
579 op = codestream_get ();
580 if (pic_pat[i] != op)
585 unsigned char buf[4];
588 op = codestream_get ();
589 if (op == 0x89) /* movl %ebx, x(%ebp) */
591 op = codestream_get ();
592 if (op == 0x5d) /* one byte offset from %ebp */
595 codestream_read (buf, 1);
597 else if (op == 0x9d) /* four byte offset from %ebp */
600 codestream_read (buf, 4);
602 else /* unexpected instruction */
604 op = codestream_get ();
607 if (delta > 0 && op == 0x81 && codestream_get () == 0xc3)
612 codestream_seek (pos);
616 return (codestream_tell ());
620 i386_push_dummy_frame ()
622 CORE_ADDR sp = read_register (SP_REGNUM);
624 char regbuf[MAX_REGISTER_RAW_SIZE];
626 sp = push_word (sp, read_register (PC_REGNUM));
627 sp = push_word (sp, read_register (FP_REGNUM));
628 write_register (FP_REGNUM, sp);
629 for (regnum = 0; regnum < NUM_REGS; regnum++)
631 read_register_gen (regnum, regbuf);
632 sp = push_bytes (sp, regbuf, REGISTER_RAW_SIZE (regnum));
634 write_register (SP_REGNUM, sp);
640 struct frame_info *frame = get_current_frame ();
643 struct frame_saved_regs fsr;
644 char regbuf[MAX_REGISTER_RAW_SIZE];
646 fp = FRAME_FP (frame);
647 get_frame_saved_regs (frame, &fsr);
648 for (regnum = 0; regnum < NUM_REGS; regnum++)
651 adr = fsr.regs[regnum];
654 read_memory (adr, regbuf, REGISTER_RAW_SIZE (regnum));
655 write_register_bytes (REGISTER_BYTE (regnum), regbuf,
656 REGISTER_RAW_SIZE (regnum));
659 write_register (FP_REGNUM, read_memory_integer (fp, 4));
660 write_register (PC_REGNUM, read_memory_integer (fp + 4, 4));
661 write_register (SP_REGNUM, fp + 8);
662 flush_cached_frames ();
665 #ifdef GET_LONGJMP_TARGET
667 /* Figure out where the longjmp will land. Slurp the args out of the stack.
668 We expect the first arg to be a pointer to the jmp_buf structure from which
669 we extract the pc (JB_PC) that we will land at. The pc is copied into PC.
670 This routine returns true on success. */
673 get_longjmp_target (pc)
676 char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
677 CORE_ADDR sp, jb_addr;
679 sp = read_register (SP_REGNUM);
681 if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack */
683 TARGET_PTR_BIT / TARGET_CHAR_BIT))
686 jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
688 if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf,
689 TARGET_PTR_BIT / TARGET_CHAR_BIT))
692 *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
697 #endif /* GET_LONGJMP_TARGET */
700 i386_extract_return_value (type, regbuf, valbuf)
702 char regbuf[REGISTER_BYTES];
705 /* On AIX, i386 GNU/Linux and DJGPP, floating point values are
706 returned in floating point registers. */
707 /* FIXME: cagney/2000-02-29: This function needs to be rewritten
708 using multi-arch. Please don't keep adding to this #ifdef
710 #if defined(I386_AIX_TARGET) || defined(I386_GNULINUX_TARGET) || defined(I386_DJGPP_TARGET)
711 if (TYPE_CODE_FLT == TYPE_CODE (type))
714 /* 387 %st(0), gcc uses this */
715 floatformat_to_double (&floatformat_i387_ext,
716 #if defined(FPDATA_REGNUM)
717 ®buf[REGISTER_BYTE (FPDATA_REGNUM)],
718 #else /* !FPDATA_REGNUM */
719 ®buf[REGISTER_BYTE (FP0_REGNUM)],
720 #endif /* FPDATA_REGNUM */
723 store_floating (valbuf, TYPE_LENGTH (type), d);
726 #endif /* I386_AIX_TARGET || I386_GNULINUX_TARGET || I386_DJGPP_TARGET */
728 #if defined(LOW_RETURN_REGNUM)
729 int len = TYPE_LENGTH (type);
730 int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM);
731 int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM);
734 memcpy (valbuf, regbuf + REGISTER_BYTE (LOW_RETURN_REGNUM), len);
735 else if (len <= (low_size + high_size))
738 regbuf + REGISTER_BYTE (LOW_RETURN_REGNUM),
740 memcpy (valbuf + low_size,
741 regbuf + REGISTER_BYTE (HIGH_RETURN_REGNUM),
745 error ("GDB bug: i386-tdep.c (i386_extract_return_value): Don't know how to find a return value %d bytes long", len);
746 #else /* !LOW_RETURN_REGNUM */
747 memcpy (valbuf, regbuf, TYPE_LENGTH (type));
748 #endif /* LOW_RETURN_REGNUM */
752 #ifdef I386V4_SIGTRAMP_SAVED_PC
753 /* Get saved user PC for sigtramp from the pushed ucontext on the stack
754 for all three variants of SVR4 sigtramps. */
757 i386v4_sigtramp_saved_pc (frame)
758 struct frame_info *frame;
760 CORE_ADDR saved_pc_offset = 4;
763 find_pc_partial_function (frame->pc, &name, NULL, NULL);
766 if (STREQ (name, "_sigreturn"))
767 saved_pc_offset = 132 + 14 * 4;
768 else if (STREQ (name, "_sigacthandler"))
769 saved_pc_offset = 80 + 14 * 4;
770 else if (STREQ (name, "sigvechandler"))
771 saved_pc_offset = 120 + 14 * 4;
775 return read_memory_integer (frame->next->frame + saved_pc_offset, 4);
776 return read_memory_integer (read_register (SP_REGNUM) + saved_pc_offset, 4);
778 #endif /* I386V4_SIGTRAMP_SAVED_PC */
780 #ifdef I386_LINUX_SIGTRAMP
782 /* When the i386 Linux kernel calls a signal handler, the return
783 address points to a bit of code on the stack. This function
784 returns whether the PC appears to be within this bit of code.
786 The instruction sequence is
790 or 0x58 0xb8 0x77 0x00 0x00 0x00 0xcd 0x80.
792 Checking for the code sequence should be somewhat reliable, because
793 the effect is to call the system call sigreturn. This is unlikely
794 to occur anywhere other than a signal trampoline.
796 It kind of sucks that we have to read memory from the process in
797 order to identify a signal trampoline, but there doesn't seem to be
798 any other way. The IN_SIGTRAMP macro in tm-linux.h arranges to
799 only call us if no function name could be identified, which should
800 be the case since the code is on the stack. */
802 #define LINUX_SIGTRAMP_INSN0 (0x58) /* pop %eax */
803 #define LINUX_SIGTRAMP_OFFSET0 (0)
804 #define LINUX_SIGTRAMP_INSN1 (0xb8) /* mov $NNNN,%eax */
805 #define LINUX_SIGTRAMP_OFFSET1 (1)
806 #define LINUX_SIGTRAMP_INSN2 (0xcd) /* int */
807 #define LINUX_SIGTRAMP_OFFSET2 (6)
809 static const unsigned char linux_sigtramp_code[] =
811 LINUX_SIGTRAMP_INSN0, /* pop %eax */
812 LINUX_SIGTRAMP_INSN1, 0x77, 0x00, 0x00, 0x00, /* mov $0x77,%eax */
813 LINUX_SIGTRAMP_INSN2, 0x80 /* int $0x80 */
816 #define LINUX_SIGTRAMP_LEN (sizeof linux_sigtramp_code)
818 /* If PC is in a sigtramp routine, return the address of the start of
819 the routine. Otherwise, return 0. */
822 i386_linux_sigtramp_start (pc)
825 unsigned char buf[LINUX_SIGTRAMP_LEN];
827 /* We only recognize a signal trampoline if PC is at the start of
828 one of the three instructions. We optimize for finding the PC at
829 the start, as will be the case when the trampoline is not the
830 first frame on the stack. We assume that in the case where the
831 PC is not at the start of the instruction sequence, there will be
832 a few trailing readable bytes on the stack. */
834 if (read_memory_nobpt (pc, (char *) buf, LINUX_SIGTRAMP_LEN) != 0)
837 if (buf[0] != LINUX_SIGTRAMP_INSN0)
843 case LINUX_SIGTRAMP_INSN1:
844 adjust = LINUX_SIGTRAMP_OFFSET1;
846 case LINUX_SIGTRAMP_INSN2:
847 adjust = LINUX_SIGTRAMP_OFFSET2;
855 if (read_memory_nobpt (pc, (char *) buf, LINUX_SIGTRAMP_LEN) != 0)
859 if (memcmp (buf, linux_sigtramp_code, LINUX_SIGTRAMP_LEN) != 0)
865 /* Return whether PC is in a Linux sigtramp routine. */
868 i386_linux_sigtramp (pc)
871 return i386_linux_sigtramp_start (pc) != 0;
874 /* Assuming FRAME is for a Linux sigtramp routine, return the saved
875 program counter. The Linux kernel will set up a sigcontext
876 structure immediately before the sigtramp routine on the stack. */
879 i386_linux_sigtramp_saved_pc (frame)
880 struct frame_info *frame;
884 pc = i386_linux_sigtramp_start (frame->pc);
886 error ("i386_linux_sigtramp_saved_pc called when no sigtramp");
887 return read_memory_integer ((pc
888 - LINUX_SIGCONTEXT_SIZE
889 + LINUX_SIGCONTEXT_PC_OFFSET),
893 /* Assuming FRAME is for a Linux sigtramp routine, return the saved
894 stack pointer. The Linux kernel will set up a sigcontext structure
895 immediately before the sigtramp routine on the stack. */
898 i386_linux_sigtramp_saved_sp (frame)
899 struct frame_info *frame;
903 pc = i386_linux_sigtramp_start (frame->pc);
905 error ("i386_linux_sigtramp_saved_sp called when no sigtramp");
906 return read_memory_integer ((pc
907 - LINUX_SIGCONTEXT_SIZE
908 + LINUX_SIGCONTEXT_SP_OFFSET),
912 #endif /* I386_LINUX_SIGTRAMP */
914 #ifdef STATIC_TRANSFORM_NAME
915 /* SunPRO encodes the static variables. This is not related to C++ mangling,
916 it is done for C too. */
919 sunpro_static_transform_name (name)
923 if (IS_STATIC_TRANSFORM_NAME (name))
925 /* For file-local statics there will be a period, a bunch
926 of junk (the contents of which match a string given in the
927 N_OPT), a period and the name. For function-local statics
928 there will be a bunch of junk (which seems to change the
929 second character from 'A' to 'B'), a period, the name of the
930 function, and the name. So just skip everything before the
932 p = strrchr (name, '.');
938 #endif /* STATIC_TRANSFORM_NAME */
942 /* Stuff for WIN32 PE style DLL's but is pretty generic really. */
945 skip_trampoline_code (pc, name)
949 if (pc && read_memory_unsigned_integer (pc, 2) == 0x25ff) /* jmp *(dest) */
951 unsigned long indirect = read_memory_unsigned_integer (pc + 2, 4);
952 struct minimal_symbol *indsym =
953 indirect ? lookup_minimal_symbol_by_pc (indirect) : 0;
954 char *symname = indsym ? SYMBOL_NAME (indsym) : 0;
958 if (strncmp (symname, "__imp_", 6) == 0
959 || strncmp (symname, "_imp_", 5) == 0)
960 return name ? 1 : read_memory_unsigned_integer (indirect, 4);
963 return 0; /* not a trampoline */
967 gdb_print_insn_i386 (memaddr, info)
969 disassemble_info *info;
971 if (disassembly_flavor == att_flavor)
972 return print_insn_i386_att (memaddr, info);
973 else if (disassembly_flavor == intel_flavor)
974 return print_insn_i386_intel (memaddr, info);
975 /* Never reached - disassembly_flavour is always either att_flavor
980 /* If the disassembly mode is intel, we have to also switch the
981 bfd mach_type. This function is run in the set disassembly_flavor
982 command, and does that. */
985 set_disassembly_flavor_sfunc (args, from_tty, c)
988 struct cmd_list_element *c;
990 set_disassembly_flavor ();
994 set_disassembly_flavor ()
996 if (disassembly_flavor == att_flavor)
997 set_architecture_from_arch_mach (bfd_arch_i386, bfd_mach_i386_i386);
998 else if (disassembly_flavor == intel_flavor)
999 set_architecture_from_arch_mach (bfd_arch_i386, bfd_mach_i386_i386_intel_syntax);
1004 _initialize_i386_tdep ()
1006 /* Initialize the table saying where each register starts in the
1012 for (i = 0; i < MAX_NUM_REGS; i++)
1014 i386_register_byte[i] = offset;
1015 offset += i386_register_raw_size[i];
1019 /* Initialize the table of virtual register sizes. */
1023 for (i = 0; i < MAX_NUM_REGS; i++)
1024 i386_register_virtual_size[i] = TYPE_LENGTH (REGISTER_VIRTUAL_TYPE (i));
1027 tm_print_insn = gdb_print_insn_i386;
1028 tm_print_insn_info.mach = bfd_lookup_arch (bfd_arch_i386, 0)->mach;
1030 /* Add the variable that controls the disassembly flavor */
1032 struct cmd_list_element *new_cmd;
1034 new_cmd = add_set_enum_cmd ("disassembly-flavor", no_class,
1036 (char *) &disassembly_flavor,
1037 "Set the disassembly flavor, the valid values are \"att\" and \"intel\", \
1038 and the default value is \"att\".",
1040 new_cmd->function.sfunc = set_disassembly_flavor_sfunc;
1041 add_show_from_set (new_cmd, &showlist);
1044 /* Finally, initialize the disassembly flavor to the default given
1045 in the disassembly_flavor variable */
1047 set_disassembly_flavor ();