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Diffstat (limited to 'gdb/sparc-pinsn.c')
-rw-r--r-- | gdb/sparc-pinsn.c | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/gdb/sparc-pinsn.c b/gdb/sparc-pinsn.c new file mode 100644 index 0000000..39d62af --- /dev/null +++ b/gdb/sparc-pinsn.c @@ -0,0 +1,465 @@ +/* Disassembler for the sparc. + Copyright (C) 1989 Free Software Foundation, Inc. + +This file is part of GDB, the GNU disassembler. + +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 "defs.h" +#include "param.h" +#include "symtab.h" +#include "sparc-opcode.h" +#include "gdbcore.h" +#include "string.h" +#include "target.h" + +extern void qsort (); + + +extern char *reg_names[]; +#define freg_names (®_names[4 * 8]) + +union sparc_insn + { + unsigned long int code; + struct + { + unsigned int OP:2; +#define op ldst.OP + unsigned int RD:5; +#define rd ldst.RD + unsigned int op3:6; + unsigned int RS1:5; +#define rs1 ldst.RS1 + unsigned int i:1; + unsigned int ASI:8; +#define asi ldst.ASI + unsigned int RS2:5; +#define rs2 ldst.RS2 +#define shcnt rs2 + } ldst; + struct + { + unsigned int OP:2, RD:5, op3:6, RS1:5, i:1; + unsigned int IMM13:13; +#define imm13 IMM13.IMM13 + } IMM13; + struct + { + unsigned int OP:2; + unsigned int a:1; + unsigned int cond:4; + unsigned int op2:3; + unsigned int DISP22:22; +#define disp22 branch.DISP22 + } branch; +#define imm22 disp22 + struct + { + unsigned int OP:2; + unsigned int DISP30:30; +#define disp30 call.DISP30 + } call; + }; + +/* Nonzero if INSN is the opcode for a delayed branch. */ +static int +is_delayed_branch (insn) + union sparc_insn insn; +{ + unsigned int i; + + for (i = 0; i < NUMOPCODES; ++i) + { + const struct sparc_opcode *opcode = &sparc_opcodes[i]; + if ((opcode->match & insn.code) == opcode->match + && (opcode->lose & insn.code) == 0) + return (opcode->flags & F_DELAYED); + } + return 0; +} + +static int opcodes_sorted = 0; + +/* Print one instruction from MEMADDR on STREAM. */ +int +print_insn (memaddr, stream) + CORE_ADDR memaddr; + FILE *stream; +{ + union sparc_insn insn; + + register unsigned int i; + + if (!opcodes_sorted) + { + static int compare_opcodes (); + qsort ((char *) sparc_opcodes, NUMOPCODES, + sizeof (sparc_opcodes[0]), compare_opcodes); + opcodes_sorted = 1; + } + + read_memory (memaddr, &insn, sizeof (insn)); + + for (i = 0; i < NUMOPCODES; ++i) + { + const struct sparc_opcode *opcode = &sparc_opcodes[i]; + if ((opcode->match & insn.code) == opcode->match + && (opcode->lose & insn.code) == 0) + { + /* Nonzero means that we have found an instruction which has + the effect of adding or or'ing the imm13 field to rs1. */ + int imm_added_to_rs1 = 0; + + /* Nonzero means that we have found a plus sign in the args + field of the opcode table. */ + int found_plus = 0; + + /* Do we have an 'or' instruction where rs1 is the same + as rsd, and which has the i bit set? */ + if (opcode->match == 0x80102000 + && insn.rs1 == insn.rd) + imm_added_to_rs1 = 1; + + if (insn.rs1 != insn.rd + && strchr (opcode->args, 'r') != 0) + /* Can't do simple format if source and dest are different. */ + continue; + + fputs_filtered (opcode->name, stream); + + { + register const char *s; + + if (opcode->args[0] != ',') + fputs_filtered (" ", stream); + for (s = opcode->args; *s != '\0'; ++s) + { + if (*s == ',') + { + fputs_filtered (",", stream); + ++s; + if (*s == 'a') + { + fputs_filtered ("a", stream); + ++s; + } + fputs_filtered (" ", stream); + } + + switch (*s) + { + case '+': + found_plus = 1; + + /* note fall-through */ + default: + fprintf_filtered (stream, "%c", *s); + break; + + case '#': + fputs_filtered ("0", stream); + break; + +#define reg(n) fprintf_filtered (stream, "%%%s", reg_names[n]) + case '1': + case 'r': + reg (insn.rs1); + break; + + case '2': + reg (insn.rs2); + break; + + case 'd': + reg (insn.rd); + break; +#undef reg + +#define freg(n) fprintf_filtered (stream, "%%%s", freg_names[n]) + case 'e': + freg (insn.rs1); + break; + + case 'f': + freg (insn.rs2); + break; + + case 'g': + freg (insn.rd); + break; +#undef freg + +#define creg(n) fprintf_filtered (stream, "%%c%u", (unsigned int) (n)) + case 'b': + creg (insn.rs1); + break; + + case 'c': + creg (insn.rs2); + break; + + case 'D': + creg (insn.rd); + break; +#undef creg + + case 'h': + fprintf_filtered (stream, "%%hi(%#x)", + (int) insn.imm22 << 10); + break; + + case 'i': + { + /* We cannot trust the compiler to sign-extend + when extracting the bitfield, hence the shifts. */ + int imm = ((int) insn.imm13 << 19) >> 19; + + /* Check to see whether we have a 1+i, and take + note of that fact. + + Note: because of the way we sort the table, + we will be matching 1+i rather than i+1, + so it is OK to assume that i is after +, + not before it. */ + if (found_plus) + imm_added_to_rs1 = 1; + + if (imm <= 9) + fprintf_filtered (stream, "%d", imm); + else + fprintf_filtered (stream, "%#x", imm); + } + break; + + case 'L': + print_address ((CORE_ADDR) memaddr + insn.disp30 * 4, + stream); + break; + + case 'l': + if ((insn.code >> 22) == 0) + /* Special case for `unimp'. Don't try to turn + it's operand into a function offset. */ + fprintf_filtered (stream, "%#x", + (int) (((int) insn.disp22 << 10) >> 10)); + else + /* We cannot trust the compiler to sign-extend + when extracting the bitfield, hence the shifts. */ + print_address ((CORE_ADDR) + (memaddr + + (((int) insn.disp22 << 10) >> 10) * 4), + stream); + break; + + case 'A': + fprintf_filtered (stream, "(%d)", (int) insn.asi); + break; + + case 'C': + fputs_filtered ("%csr", stream); + break; + + case 'F': + fputs_filtered ("%fsr", stream); + break; + + case 'p': + fputs_filtered ("%psr", stream); + break; + + case 'q': + fputs_filtered ("%fq", stream); + break; + + case 'Q': + fputs_filtered ("%cq", stream); + break; + + case 't': + fputs_filtered ("%tbr", stream); + break; + + case 'w': + fputs_filtered ("%wim", stream); + break; + + case 'y': + fputs_filtered ("%y", stream); + break; + } + } + } + + /* If we are adding or or'ing something to rs1, then + check to see whether the previous instruction was + a sethi to the same register as in the sethi. + If so, attempt to print the result of the add or + or (in this context add and or do the same thing) + and its symbolic value. */ + if (imm_added_to_rs1) + { + union sparc_insn prev_insn; + int errcode; + + errcode = target_read_memory (memaddr - 4, + (char *)&prev_insn, sizeof (prev_insn)); + + if (errcode == 0) + { + /* If it is a delayed branch, we need to look at the + instruction before the delayed branch. This handles + sequences such as + + sethi %o1, %hi(_foo), %o1 + call _printf + or %o1, %lo(_foo), %o1 + */ + + if (is_delayed_branch (prev_insn)) + errcode = target_read_memory + (memaddr - 8, (char *)&prev_insn, sizeof (prev_insn)); + } + + /* If there was a problem reading memory, then assume + the previous instruction was not sethi. */ + if (errcode == 0) + { + /* Is it sethi to the same register? */ + if ((prev_insn.code & 0xc1c00000) == 0x01000000 + && prev_insn.rd == insn.rs1) + { + fprintf_filtered (stream, "\t! "); + /* We cannot trust the compiler to sign-extend + when extracting the bitfield, hence the shifts. */ + print_address (((int) prev_insn.imm22 << 10) + | (insn.imm13 << 19) >> 19, stream); + } + } + } + + return sizeof (insn); + } + } + + printf_filtered ("%#8x", insn.code); + return sizeof (insn); +} + + +/* Compare opcodes A and B. */ + +static int +compare_opcodes (a, b) + char *a, *b; +{ + struct sparc_opcode *op0 = (struct sparc_opcode *) a; + struct sparc_opcode *op1 = (struct sparc_opcode *) b; + unsigned long int match0 = op0->match, match1 = op1->match; + unsigned long int lose0 = op0->lose, lose1 = op1->lose; + register unsigned int i; + + /* If a bit is set in both match and lose, there is something + wrong with the opcode table. */ + if (match0 & lose0) + { + fprintf (stderr, "Internal error: bad sparc-opcode.h: \"%s\", %#.8lx, %#.8lx\n", + op0->name, match0, lose0); + op0->lose &= ~op0->match; + lose0 = op0->lose; + } + + if (match1 & lose1) + { + fprintf (stderr, "Internal error: bad sparc-opcode.h: \"%s\", %#.8lx, %#.8lx\n", + op1->name, match1, lose1); + op1->lose &= ~op1->match; + lose1 = op1->lose; + } + + /* Because the bits that are variable in one opcode are constant in + another, it is important to order the opcodes in the right order. */ + for (i = 0; i < 32; ++i) + { + unsigned long int x = 1 << i; + int x0 = (match0 & x) != 0; + int x1 = (match1 & x) != 0; + + if (x0 != x1) + return x1 - x0; + } + + for (i = 0; i < 32; ++i) + { + unsigned long int x = 1 << i; + int x0 = (lose0 & x) != 0; + int x1 = (lose1 & x) != 0; + + if (x0 != x1) + return x1 - x0; + } + + /* They are functionally equal. So as long as the opcode table is + valid, we can put whichever one first we want, on aesthetic grounds. */ + + /* Our first aesthetic ground is that aliases defer to real insns. */ + { + int alias_diff = (op0->flags & F_ALIAS) - (op1->flags & F_ALIAS); + if (alias_diff != 0) + /* Put the one that isn't an alias first. */ + return alias_diff; + } + + /* Except for the above aliases, two "identical" instructions had + better have the same opcode. This is a sanity check on the table. */ + if (0 != strcmp (op0->name, op1->name)) + fprintf (stderr, "Internal error: bad sparc-opcode.h: \"%s\" == \"%s\"\n", + op0->name, op1->name); + + /* Fewer arguments are preferred. */ + { + int length_diff = strlen (op0->args) - strlen (op1->args); + if (length_diff != 0) + /* Put the one with fewer arguments first. */ + return length_diff; + } + + /* Put 1+i before i+1. */ + { + char *p0 = (char *) strchr(op0->args, '+'); + char *p1 = (char *) strchr(op1->args, '+'); + + if (p0 && p1) + { + /* There is a plus in both operands. Note that a plus + sign cannot be the first character in args, + so the following [-1]'s are valid. */ + if (p0[-1] == 'i' && p1[1] == 'i') + /* op0 is i+1 and op1 is 1+i, so op1 goes first. */ + return 1; + if (p0[1] == 'i' && p1[-1] == 'i') + /* op0 is 1+i and op1 is i+1, so op0 goes first. */ + return -1; + } + } + + /* They are, as far as we can tell, identical. + Since qsort may have rearranged the table partially, there is + no way to tell which one was first in the opcode table as + written, so just say there are equal. */ + return 0; +} |