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author | Stan Shebs <shebs@codesourcery.com> | 1999-04-16 01:34:07 +0000 |
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committer | Stan Shebs <shebs@codesourcery.com> | 1999-04-16 01:34:07 +0000 |
commit | 071ea11e85eb9d529cc5eb3d35f6247466a21b99 (patch) | |
tree | 5deda65b8d7b04d1f4cbc534c3206d328e1267ec /gdb/arc-tdep.c | |
parent | 1730ec6b1848f0f32154277f788fb29f88d8475b (diff) | |
download | gdb-071ea11e85eb9d529cc5eb3d35f6247466a21b99.zip gdb-071ea11e85eb9d529cc5eb3d35f6247466a21b99.tar.gz gdb-071ea11e85eb9d529cc5eb3d35f6247466a21b99.tar.bz2 |
Initial creation of sourceware repository
Diffstat (limited to 'gdb/arc-tdep.c')
-rw-r--r-- | gdb/arc-tdep.c | 733 |
1 files changed, 0 insertions, 733 deletions
diff --git a/gdb/arc-tdep.c b/gdb/arc-tdep.c deleted file mode 100644 index 9295770..0000000 --- a/gdb/arc-tdep.c +++ /dev/null @@ -1,733 +0,0 @@ -/* ARC target-dependent stuff. - Copyright (C) 1995, 1997 Free Software Foundation, Inc. - -This file is part of GDB. - -This program is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2 of the License, or -(at your option) any later version. - -This program is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with this program; if not, write to the Free Software -Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ - -#include "defs.h" -#include "frame.h" -#include "inferior.h" -#include "gdbcore.h" -#include "target.h" -#include "floatformat.h" -#include "symtab.h" -#include "gdbcmd.h" - -/* Current CPU, set with the "set cpu" command. */ -static int arc_bfd_mach_type; -char *arc_cpu_type; -char *tmp_arc_cpu_type; - -/* Table of cpu names. */ -struct { - char *name; - int value; -} arc_cpu_type_table[] = { - { "base", bfd_mach_arc_base }, - { NULL, 0 } -}; - -/* Used by simulator. */ -int display_pipeline_p; -int cpu_timer; -/* This one must have the same type as used in the emulator. - It's currently an enum so this should be ok for now. */ -int debug_pipeline_p; - -#define ARC_CALL_SAVED_REG(r) ((r) >= 16 && (r) < 24) - -#define OPMASK 0xf8000000 - -/* Instruction field accessor macros. - See the Programmer's Reference Manual. */ -#define X_OP(i) (((i) >> 27) & 0x1f) -#define X_A(i) (((i) >> 21) & 0x3f) -#define X_B(i) (((i) >> 15) & 0x3f) -#define X_C(i) (((i) >> 9) & 0x3f) -#define X_D(i) ((((i) & 0x1ff) ^ 0x100) - 0x100) -#define X_L(i) (((((i) >> 5) & 0x3ffffc) ^ 0x200000) - 0x200000) -#define X_N(i) (((i) >> 5) & 3) -#define X_Q(i) ((i) & 0x1f) - -/* Return non-zero if X is a short immediate data indicator. */ -#define SHIMM_P(x) ((x) == 61 || (x) == 63) - -/* Return non-zero if X is a "long" (32 bit) immediate data indicator. */ -#define LIMM_P(x) ((x) == 62) - -/* Build a simple instruction. */ -#define BUILD_INSN(op, a, b, c, d) \ - ((((op) & 31) << 27) \ - | (((a) & 63) << 21) \ - | (((b) & 63) << 15) \ - | (((c) & 63) << 9) \ - | ((d) & 511)) - -/* Codestream stuff. */ -static void codestream_read PARAMS ((unsigned int *, int)); -static void codestream_seek PARAMS ((CORE_ADDR)); -static unsigned int codestream_fill PARAMS ((int)); - -#define CODESTREAM_BUFSIZ 16 -static CORE_ADDR codestream_next_addr; -static CORE_ADDR codestream_addr; -static unsigned int codestream_buf[CODESTREAM_BUFSIZ]; -static int codestream_off; -static int codestream_cnt; - -#define codestream_tell() \ - (codestream_addr + codestream_off * sizeof (codestream_buf[0])) -#define codestream_peek() \ - (codestream_cnt == 0 \ - ? codestream_fill (1) \ - : codestream_buf[codestream_off]) -#define codestream_get() \ - (codestream_cnt-- == 0 \ - ? codestream_fill (0) \ - : codestream_buf[codestream_off++]) - -static unsigned int -codestream_fill (peek_flag) - int peek_flag; -{ - codestream_addr = codestream_next_addr; - codestream_next_addr += CODESTREAM_BUFSIZ * sizeof (codestream_buf[0]); - codestream_off = 0; - codestream_cnt = CODESTREAM_BUFSIZ; - read_memory (codestream_addr, (char *) codestream_buf, - CODESTREAM_BUFSIZ * sizeof (codestream_buf[0])); - /* FIXME: check return code? */ - - /* Handle byte order differences. */ - if (HOST_BYTE_ORDER != TARGET_BYTE_ORDER) - { - register unsigned int i, j, n = sizeof (codestream_buf[0]); - register char tmp, *p; - for (i = 0, p = (char *) codestream_buf; i < CODESTREAM_BUFSIZ; - ++i, p += n) - for (j = 0; j < n / 2; ++j) - tmp = p[j], p[j] = p[n - 1 - j], p[n - 1 - j] = tmp; - } - - if (peek_flag) - return codestream_peek (); - else - return codestream_get (); -} - -static void -codestream_seek (place) - CORE_ADDR place; -{ - codestream_next_addr = place / CODESTREAM_BUFSIZ; - codestream_next_addr *= CODESTREAM_BUFSIZ; - codestream_cnt = 0; - codestream_fill (1); - while (codestream_tell () != place) - codestream_get (); -} - -/* This function is currently unused but leave in for now. */ - -static void -codestream_read (buf, count) - unsigned int *buf; - int count; -{ - unsigned int *p; - int i; - p = buf; - for (i = 0; i < count; i++) - *p++ = codestream_get (); -} - -/* Set up prologue scanning and return the first insn. */ - -static unsigned int -setup_prologue_scan (pc) - CORE_ADDR pc; -{ - unsigned int insn; - - codestream_seek (pc); - insn = codestream_get (); - - return insn; -} - -/* - * Find & return amount a local space allocated, and advance codestream to - * first register push (if any). - * If entry sequence doesn't make sense, return -1, and leave - * codestream pointer random. - */ - -static long -arc_get_frame_setup (pc) - CORE_ADDR pc; -{ - unsigned int insn; - /* Size of frame or -1 if unrecognizable prologue. */ - int frame_size = -1; - /* An initial "sub sp,sp,N" may or may not be for a stdarg fn. */ - int maybe_stdarg_decr = -1; - - insn = setup_prologue_scan (pc); - - /* The authority for what appears here is the home-grown ABI. - The most recent version is 1.2. */ - - /* First insn may be "sub sp,sp,N" if stdarg fn. */ - if ((insn & BUILD_INSN (-1, -1, -1, -1, 0)) - == BUILD_INSN (10, SP_REGNUM, SP_REGNUM, SHIMM_REGNUM, 0)) - { - maybe_stdarg_decr = X_D (insn); - insn = codestream_get (); - } - - if ((insn & BUILD_INSN (-1, 0, -1, -1, -1)) /* st blink,[sp,4] */ - == BUILD_INSN (2, 0, SP_REGNUM, BLINK_REGNUM, 4)) - { - insn = codestream_get (); - /* Frame may not be necessary, even though blink is saved. - At least this is something we recognize. */ - frame_size = 0; - } - - if ((insn & BUILD_INSN (-1, 0, -1, -1, -1)) /* st fp,[sp] */ - == BUILD_INSN (2, 0, SP_REGNUM, FP_REGNUM, 0)) - { - insn = codestream_get (); - if ((insn & BUILD_INSN (-1, -1, -1, -1, 0)) - != BUILD_INSN (12, FP_REGNUM, SP_REGNUM, SP_REGNUM, 0)) - return -1; - - /* Check for stack adjustment sub sp,sp,N. */ - insn = codestream_peek (); - if ((insn & BUILD_INSN (-1, -1, -1, 0, 0)) - == BUILD_INSN (10, SP_REGNUM, SP_REGNUM, 0, 0)) - { - if (LIMM_P (X_C (insn))) - frame_size = codestream_get (); - else if (SHIMM_P (X_C (insn))) - frame_size = X_D (insn); - else - return -1; - if (frame_size < 0) - return -1; - - codestream_get (); - - /* This sequence is used to get the address of the return - buffer for a function that returns a structure. */ - insn = codestream_peek (); - if (insn & OPMASK == 0x60000000) - codestream_get (); - } - /* Frameless fn. */ - else - { - frame_size = 0; - } - } - - /* If we found a "sub sp,sp,N" and nothing else, it may or may not be a - stdarg fn. The stdarg decrement is not treated as part of the frame size, - so we have a dilemma: what do we return? For now, if we get a - "sub sp,sp,N" and nothing else assume this isn't a stdarg fn. One way - to fix this completely would be to add a bit to the function descriptor - that says the function is a stdarg function. */ - - if (frame_size < 0 && maybe_stdarg_decr > 0) - return maybe_stdarg_decr; - return frame_size; -} - -/* Given a pc value, skip it forward past the function prologue by - disassembling instructions that appear to be a prologue. - - If FRAMELESS_P is set, we are only testing to see if the function - is frameless. If it is a frameless function, return PC unchanged. - This allows a quicker answer. */ - -CORE_ADDR -skip_prologue (pc, frameless_p) - CORE_ADDR pc; - int frameless_p; -{ - unsigned int insn; - int i, frame_size; - - if ((frame_size = arc_get_frame_setup (pc)) < 0) - return (pc); - - if (frameless_p) - return frame_size == 0 ? pc : codestream_tell (); - - /* Skip over register saves. */ - for (i = 0; i < 8; i++) - { - insn = codestream_peek (); - if ((insn & BUILD_INSN (-1, 0, -1, 0, 0)) - != BUILD_INSN (2, 0, SP_REGNUM, 0, 0)) - break; /* not st insn */ - if (! ARC_CALL_SAVED_REG (X_C (insn))) - break; - codestream_get (); - } - - return codestream_tell (); -} - -/* Return the return address for a frame. - This is used to implement FRAME_SAVED_PC. - This is taken from frameless_look_for_prologue. */ - -CORE_ADDR -arc_frame_saved_pc (frame) - struct frame_info *frame; -{ - CORE_ADDR func_start; - unsigned int insn; - - func_start = get_pc_function_start (frame->pc) + FUNCTION_START_OFFSET; - if (func_start == 0) - { - /* Best guess. */ - return ARC_PC_TO_REAL_ADDRESS (read_memory_integer (FRAME_FP (frame) + 4, 4)); - } - - /* The authority for what appears here is the home-grown ABI. - The most recent version is 1.2. */ - - insn = setup_prologue_scan (func_start); - - /* First insn may be "sub sp,sp,N" if stdarg fn. */ - if ((insn & BUILD_INSN (-1, -1, -1, -1, 0)) - == BUILD_INSN (10, SP_REGNUM, SP_REGNUM, SHIMM_REGNUM, 0)) - insn = codestream_get (); - - /* If the next insn is "st blink,[sp,4]" we can get blink from there. - Otherwise this is a leaf function and we can use blink. Note that - this still allows for the case where a leaf function saves/clobbers/ - restores blink. */ - - if ((insn & BUILD_INSN (-1, 0, -1, -1, -1)) /* st blink,[sp,4] */ - != BUILD_INSN (2, 0, SP_REGNUM, BLINK_REGNUM, 4)) - return ARC_PC_TO_REAL_ADDRESS (read_register (BLINK_REGNUM)); - else - return ARC_PC_TO_REAL_ADDRESS (read_memory_integer (FRAME_FP (frame) + 4, 4)); -} - -/* - * Parse the first few instructions of the function to see - * what registers were stored. - * - * The startup sequence can be at the start of the function. - * 'st blink,[sp+4], st fp,[sp], mov fp,sp' - * - * Local space is allocated just below by sub sp,sp,nnn. - * Next, the registers used by this function are stored (as offsets from sp). - */ - -void -frame_find_saved_regs (fip, fsrp) - struct frame_info *fip; - struct frame_saved_regs *fsrp; -{ - long locals; - unsigned int insn; - CORE_ADDR dummy_bottom; - CORE_ADDR adr; - int i, regnum, offset; - - memset (fsrp, 0, sizeof *fsrp); - - /* If frame is the end of a dummy, compute where the beginning would be. */ - dummy_bottom = fip->frame - 4 - REGISTER_BYTES - CALL_DUMMY_LENGTH; - - /* Check if the PC is in the stack, in a dummy frame. */ - if (dummy_bottom <= fip->pc && fip->pc <= fip->frame) - { - /* all regs were saved by push_call_dummy () */ - adr = fip->frame; - for (i = 0; i < NUM_REGS; i++) - { - adr -= REGISTER_RAW_SIZE (i); - fsrp->regs[i] = adr; - } - return; - } - - locals = arc_get_frame_setup (get_pc_function_start (fip->pc)); - - if (locals >= 0) - { - /* Set `adr' to the value of `sp'. */ - adr = fip->frame - locals; - for (i = 0; i < 8; i++) - { - insn = codestream_get (); - if ((insn & BUILD_INSN (-1, 0, -1, 0, 0)) - != BUILD_INSN (2, 0, SP_REGNUM, 0, 0)) - break; - regnum = X_C (insn); - offset = X_D (insn); - fsrp->regs[regnum] = adr + offset; - } - } - - fsrp->regs[PC_REGNUM] = fip->frame + 4; - fsrp->regs[FP_REGNUM] = fip->frame; -} - -void -push_dummy_frame () -{ - CORE_ADDR sp = read_register (SP_REGNUM); - int regnum; - char regbuf[MAX_REGISTER_RAW_SIZE]; - - read_register_gen (PC_REGNUM, regbuf); - write_memory (sp+4, regbuf, REGISTER_SIZE); - read_register_gen (FP_REGNUM, regbuf); - write_memory (sp, regbuf, REGISTER_SIZE); - write_register (FP_REGNUM, sp); - for (regnum = 0; regnum < NUM_REGS; regnum++) - { - read_register_gen (regnum, regbuf); - sp = push_bytes (sp, regbuf, REGISTER_RAW_SIZE (regnum)); - } - sp += (2*REGISTER_SIZE); - write_register (SP_REGNUM, sp); -} - -void -pop_frame () -{ - struct frame_info *frame = get_current_frame (); - CORE_ADDR fp; - int regnum; - struct frame_saved_regs fsr; - char regbuf[MAX_REGISTER_RAW_SIZE]; - - fp = FRAME_FP (frame); - get_frame_saved_regs (frame, &fsr); - for (regnum = 0; regnum < NUM_REGS; regnum++) - { - CORE_ADDR adr; - adr = fsr.regs[regnum]; - if (adr) - { - read_memory (adr, regbuf, REGISTER_RAW_SIZE (regnum)); - write_register_bytes (REGISTER_BYTE (regnum), regbuf, - REGISTER_RAW_SIZE (regnum)); - } - } - write_register (FP_REGNUM, read_memory_integer (fp, 4)); - write_register (PC_REGNUM, read_memory_integer (fp + 4, 4)); - write_register (SP_REGNUM, fp + 8); - flush_cached_frames (); -} - -/* Simulate single-step. */ - -typedef enum -{ - NORMAL4, /* a normal 4 byte insn */ - NORMAL8, /* a normal 8 byte insn */ - BRANCH4, /* a 4 byte branch insn, including ones without delay slots */ - BRANCH8, /* an 8 byte branch insn, including ones with delay slots */ -} insn_type; - -/* Return the type of INSN and store in TARGET the destination address of a - branch if this is one. */ -/* ??? Need to verify all cases are properly handled. */ - -static insn_type -get_insn_type (insn, pc, target) - unsigned long insn; - CORE_ADDR pc, *target; -{ - unsigned long limm; - - switch (insn >> 27) - { - case 0 : case 1 : case 2 : /* load/store insns */ - if (LIMM_P (X_A (insn)) - || LIMM_P (X_B (insn)) - || LIMM_P (X_C (insn))) - return NORMAL8; - return NORMAL4; - case 4 : case 5 : case 6 : /* branch insns */ - *target = pc + 4 + X_L (insn); - /* ??? It isn't clear that this is always the right answer. - The problem occurs when the next insn is an 8 byte insn. If the - branch is conditional there's no worry as there shouldn't be an 8 - byte insn following. The programmer may be cheating if s/he knows - the branch will never be taken, but we don't deal with that. - Note that the programmer is also allowed to play games by putting - an insn with long immediate data in the delay slot and then duplicate - the long immediate data at the branch target. Ugh! */ - if (X_N (insn) == 0) - return BRANCH4; - return BRANCH8; - case 7 : /* jump insns */ - if (LIMM_P (X_B (insn))) - { - limm = read_memory_integer (pc + 4, 4); - *target = ARC_PC_TO_REAL_ADDRESS (limm); - return BRANCH8; - } - if (SHIMM_P (X_B (insn))) - *target = ARC_PC_TO_REAL_ADDRESS (X_D (insn)); - else - *target = ARC_PC_TO_REAL_ADDRESS (read_register (X_B (insn))); - if (X_Q (insn) == 0 && X_N (insn) == 0) - return BRANCH4; - return BRANCH8; - default : /* arithmetic insns, etc. */ - if (LIMM_P (X_A (insn)) - || LIMM_P (X_B (insn)) - || LIMM_P (X_C (insn))) - return NORMAL8; - return NORMAL4; - } -} - -/* single_step() is called just before we want to resume the inferior, if we - want to single-step it but there is no hardware or kernel single-step - support. We find all the possible targets of the coming instruction and - breakpoint them. - - single_step is also called just after the inferior stops. If we had - set up a simulated single-step, we undo our damage. */ - -void -arc_software_single_step (ignore, insert_breakpoints_p) - enum target_signal ignore; /* sig but we don't need it */ - int insert_breakpoints_p; -{ - static CORE_ADDR next_pc, target; - static int brktrg_p; - typedef char binsn_quantum[BREAKPOINT_MAX]; - static binsn_quantum break_mem[2]; - - if (insert_breakpoints_p) - { - insn_type type; - CORE_ADDR pc; - unsigned long insn; - - pc = read_register (PC_REGNUM); - insn = read_memory_integer (pc, 4); - type = get_insn_type (insn, pc, &target); - - /* Always set a breakpoint for the insn after the branch. */ - next_pc = pc + ((type == NORMAL8 || type == BRANCH8) ? 8 : 4); - target_insert_breakpoint (next_pc, break_mem[0]); - - brktrg_p = 0; - - if ((type == BRANCH4 || type == BRANCH8) - /* Watch out for branches to the following location. - We just stored a breakpoint there and another call to - target_insert_breakpoint will think the real insn is the - breakpoint we just stored there. */ - && target != next_pc) - { - brktrg_p = 1; - target_insert_breakpoint (target, break_mem[1]); - } - - } - else - { - /* Remove breakpoints. */ - target_remove_breakpoint (next_pc, break_mem[0]); - - if (brktrg_p) - target_remove_breakpoint (target, break_mem[1]); - - /* Fix the pc. */ - stop_pc -= DECR_PC_AFTER_BREAK; - write_pc (stop_pc); - } -} - -#ifdef GET_LONGJMP_TARGET -/* Figure out where the longjmp will land. Slurp the args out of the stack. - We expect the first arg to be a pointer to the jmp_buf structure from which - we extract the pc (JB_PC) that we will land at. The pc is copied into PC. - This routine returns true on success. */ - -int -get_longjmp_target(pc) - CORE_ADDR *pc; -{ - char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT]; - CORE_ADDR sp, jb_addr; - - sp = read_register (SP_REGNUM); - - if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack */ - buf, - TARGET_PTR_BIT / TARGET_CHAR_BIT)) - return 0; - - jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); - - if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf, - TARGET_PTR_BIT / TARGET_CHAR_BIT)) - return 0; - - *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); - - return 1; -} -#endif /* GET_LONGJMP_TARGET */ - -/* Disassemble one instruction. */ - -static int -arc_print_insn (vma, info) - bfd_vma vma; - disassemble_info *info; -{ - static int current_mach; - static int current_endian; - static disassembler_ftype current_disasm; - - if (current_disasm == NULL - || arc_bfd_mach_type != current_mach - || TARGET_BYTE_ORDER != current_endian) - { - current_mach = arc_bfd_mach_type; - current_endian = TARGET_BYTE_ORDER; - current_disasm = arc_get_disassembler (current_mach, - current_endian == BIG_ENDIAN); - } - - return (*current_disasm) (vma, info); -} - -/* Command to set cpu type. */ - -void -arc_set_cpu_type_command (args, from_tty) - char *args; - int from_tty; -{ - int i; - - if (tmp_arc_cpu_type == NULL || *tmp_arc_cpu_type == '\0') - { - printf_unfiltered ("The known ARC cpu types are as follows:\n"); - for (i = 0; arc_cpu_type_table[i].name != NULL; ++i) - printf_unfiltered ("%s\n", arc_cpu_type_table[i].name); - - /* Restore the value. */ - tmp_arc_cpu_type = strsave (arc_cpu_type); - - return; - } - - if (!arc_set_cpu_type (tmp_arc_cpu_type)) - { - error ("Unknown cpu type `%s'.", tmp_arc_cpu_type); - /* Restore its value. */ - tmp_arc_cpu_type = strsave (arc_cpu_type); - } -} - -static void -arc_show_cpu_type_command (args, from_tty) - char *args; - int from_tty; -{ -} - -/* Modify the actual cpu type. - Result is a boolean indicating success. */ - -int -arc_set_cpu_type (str) - char *str; -{ - int i, j; - - if (str == NULL) - return 0; - - for (i = 0; arc_cpu_type_table[i].name != NULL; ++i) - { - if (strcasecmp (str, arc_cpu_type_table[i].name) == 0) - { - arc_cpu_type = str; - arc_bfd_mach_type = arc_cpu_type_table[i].value; - return 1; - } - } - - return 0; -} - -void -_initialize_arc_tdep () -{ - struct cmd_list_element *c; - - c = add_set_cmd ("cpu", class_support, var_string_noescape, - (char *) &tmp_arc_cpu_type, - "Set the type of ARC cpu in use.\n\ -This command has two purposes. In a multi-cpu system it lets one\n\ -change the cpu being debugged. It also gives one access to\n\ -cpu-type-specific registers and recognize cpu-type-specific instructions.\ -", - &setlist); - c->function.cfunc = arc_set_cpu_type_command; - c = add_show_from_set (c, &showlist); - c->function.cfunc = arc_show_cpu_type_command; - - /* We have to use strsave here because the `set' command frees it before - setting a new value. */ - tmp_arc_cpu_type = strsave (DEFAULT_ARC_CPU_TYPE); - arc_set_cpu_type (tmp_arc_cpu_type); - - c = add_set_cmd ("displaypipeline", class_support, var_zinteger, - (char *) &display_pipeline_p, - "Set pipeline display (simulator only).\n\ -When enabled, the state of the pipeline after each cycle is displayed.", - &setlist); - c = add_show_from_set (c, &showlist); - - c = add_set_cmd ("debugpipeline", class_support, var_zinteger, - (char *) &debug_pipeline_p, - "Set pipeline debug display (simulator only).\n\ -When enabled, debugging information about the pipeline is displayed.", - &setlist); - c = add_show_from_set (c, &showlist); - - c = add_set_cmd ("cputimer", class_support, var_zinteger, - (char *) &cpu_timer, - "Set maximum cycle count (simulator only).\n\ -Control will return to gdb if the timer expires.\n\ -A negative value disables the timer.", - &setlist); - c = add_show_from_set (c, &showlist); - - tm_print_insn = arc_print_insn; -} |