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Diffstat (limited to 'gdb/gould-pinsn.c')
-rw-r--r-- | gdb/gould-pinsn.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/gdb/gould-pinsn.c b/gdb/gould-pinsn.c new file mode 100644 index 0000000..b655f26 --- /dev/null +++ b/gdb/gould-pinsn.c @@ -0,0 +1,294 @@ +/* Print GOULD RISC instructions for GDB, the GNU debugger. + Copyright (C) 1986, 1987, 1989 Free Software Foundation, Inc. + +This file is part of GDB. + +GDB 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 1, or (at your option) +any later version. + +GDB 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 GDB; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include <stdio.h> +#include "gdbcore.h" + +#include "defs.h" +#include "param.h" +#include "symtab.h" +#include "frame.h" +#if defined GOULD_PN +#include "pn-opcode.h" +#else +#include "np1-opcode.h" +#endif + +/* GOULD RISC instructions are never longer than this many bytes. */ +#define MAXLEN 4 + +/* Number of elements in the opcode table. */ +#define NOPCODES (sizeof gld_opcodes / sizeof gld_opcodes[0]) + + +/* Print the GOULD instruction at address MEMADDR in debugged memory, + on STREAM. Returns length of the instruction, in bytes. */ + +int +print_insn (memaddr, stream) + CORE_ADDR memaddr; + FILE *stream; +{ + unsigned char buffer[MAXLEN]; + register int i; + register char *d; + register int bestmask; + unsigned best; + int temp, index, bestlen; + + read_memory (memaddr, buffer, MAXLEN); + + bestmask = 0; + index = -1; + best = 0xffffffff; + for (i = 0; i < NOPCODES; i++) + { + register unsigned int opcode = gld_opcodes[i].opcode; + register unsigned int mask = gld_opcodes[i].mask; + register unsigned int len = gld_opcodes[i].length; + register unsigned int test; + + /* Get possible opcode bytes into integer */ + test = buffer[0] << 24; + test |= buffer[1] << 16; + test |= buffer[2] << 8; + test |= buffer[3]; + + /* Mask with opcode and see if match */ + if ((opcode & mask) == (test & mask)) + { + /* See if second or third match */ + if (index >= 0) + { + /* Take new one if it looks good */ + if (bestlen == MAXLEN && len == MAXLEN) + { + /* See if lower bits matched */ + if (((bestmask & 3) == 0) && + ((mask & 3) != 0)) + { + bestmask = mask; + bestlen = len; + best = test; + index = i; + } + } + } + else + { + /* First match, save it */ + bestmask = mask; + bestlen = len; + best = test; + index = i; + } + } + } + + /* Handle undefined instructions. */ + if (index < 0) + { + fprintf (stream, "undefined 0%o",(buffer[0]<<8)+buffer[1]); + return 2; + } + + /* Print instruction name */ + fprintf (stream, "%-12s", gld_opcodes[index].name); + + /* Adjust if short instruction */ + if (gld_opcodes[index].length < 4) + { + best >>= 16; + i = 0; + } + else + { + i = 16; + } + + /* Dump out instruction arguments */ + for (d = gld_opcodes[index].args; *d; ++d) + { + switch (*d) + { + case 'f': + fprintf (stream, "%d", (best >> (7 + i)) & 7); + break; + case 'r': + fprintf (stream, "r%d", (best >> (7 + i)) & 7); + break; + case 'R': + fprintf (stream, "r%d", (best >> (4 + i)) & 7); + break; + case 'b': + fprintf (stream, "b%d", (best >> (7 + i)) & 7); + break; + case 'B': + fprintf (stream, "b%d", (best >> (4 + i)) & 7); + break; + case 'v': + fprintf (stream, "b%d", (best >> (7 + i)) & 7); + break; + case 'V': + fprintf (stream, "b%d", (best >> (4 + i)) & 7); + break; + case 'X': + temp = (best >> 20) & 7; + if (temp) + fprintf (stream, "r%d", temp); + else + putc ('0', stream); + break; + case 'A': + temp = (best >> 16) & 7; + if (temp) + fprintf (stream, "(b%d)", temp); + break; + case 'S': + fprintf (stream, "#%d", best & 0x1f); + break; + case 'I': + fprintf (stream, "#%x", best & 0xffff); + break; + case 'O': + fprintf (stream, "%x", best & 0xffff); + break; + case 'h': + fprintf (stream, "%d", best & 0xfffe); + break; + case 'd': + fprintf (stream, "%d", best & 0xfffc); + break; + case 'T': + fprintf (stream, "%d", (best >> 8) & 0xff); + break; + case 'N': + fprintf (stream, "%d", best & 0xff); + break; + default: + putc (*d, stream); + break; + } + } + + /* Return length of instruction */ + return (gld_opcodes[index].length); +} + +/* + * Find the number of arguments to a function. + */ +findarg(frame) + struct frame_info *frame; +{ + register struct symbol *func; + register unsigned pc; + +#ifdef notdef + /* find starting address of frame function */ + pc = get_pc_function_start (frame->pc); + + /* find function symbol info */ + func = find_pc_function (pc); + + /* call blockframe code to look for match */ + if (func != NULL) + return (func->value.block->nsyms / sizeof(int)); +#endif + + return (-1); +} + +/* + * In the case of the NPL, the frame's norminal address is Br2 and the + * previous routines frame is up the stack X bytes. Finding out what + * 'X' is can be tricky. + * + * 1.) stored in the code function header xA(Br1). + * 2.) must be careful of recurssion. + */ +FRAME_ADDR +findframe(thisframe) + FRAME thisframe; +{ + register FRAME_ADDR pointer; + FRAME_ADDR framechain(); +#if 0 + struct frame_info *frame; + + /* Setup toplevel frame structure */ + frame->pc = read_pc(); + frame->next_frame = 0; + frame->frame = read_register (SP_REGNUM); /* Br2 */ + + /* Search for this frame (start at current Br2) */ + do + { + pointer = framechain(frame); + frame->next_frame = frame->frame; + frame->frame = pointer; + frame->pc = FRAME_SAVED_PC(frame); + } + while (frame->next_frame != thisframe); +#endif + + pointer = framechain (thisframe); + + /* stop gap for now, end at __base3 */ + if (thisframe->pc == 0) + return 0; + + return pointer; +} + +/* + * Gdb front-end and internal framechain routine. + * Go back up stack one level. Tricky... + */ +FRAME_ADDR +framechain(frame) + register struct frame_info *frame; +{ + register CORE_ADDR func, prevsp; + register unsigned value; + + /* Get real function start address from internal frame address */ + func = get_pc_function_start(frame->pc); + + /* If no stack given, read register Br1 "(sp)" */ + if (!frame->frame) + prevsp = read_register (SP_REGNUM); + else + prevsp = frame->frame; + + /* Check function header, case #2 */ + value = read_memory_integer (func, 4); + if (value) + { + /* 32bit call push value stored in function header */ + prevsp += value; + } + else + { + /* read half-word from suabr at start of function */ + prevsp += read_memory_integer (func + 10, 2); + } + + return (prevsp); +} |