/* Print SPARC instructions for GDB, the GNU Debugger. Copyright 1989, 1991, 1992 Free Software Foundation, Inc. This file is part of GDB, the GNU debugger. 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "defs.h" #include "symtab.h" #include "opcode/sparc.h" #include "gdbcore.h" #include <string.h> #include "target.h" #define freg_names (®_names[4 * 8]) union sparc_insn { unsigned long int code; struct { unsigned int anop:2; #define op ldst.anop unsigned int anrd:5; #define rd ldst.anrd unsigned int op3:6; unsigned int anrs1:5; #define rs1 ldst.anrs1 unsigned int i:1; unsigned int anasi:8; #define asi ldst.anasi unsigned int anrs2:5; #define rs2 ldst.anrs2 #define shcnt rs2 } ldst; struct { unsigned int anop:2, anrd:5, op3:6, anrs1:5, i:1; unsigned int IMM13:13; #define imm13 IMM13.IMM13 } IMM13; struct { unsigned int anop: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 anop:2; unsigned int adisp30:30; #define disp30 call.adisp30 } 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; extern void qsort (); /* Print one instruction from MEMADDR on STREAM. We suffix the instruction with a comment that gives the absolute address involved, as well as its symbolic form, if the instruction is preceded by a findable `sethi' and it either adds an immediate displacement to that register, or it is an `add' or `or' instruction on that register. */ 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, (char *) &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 `add' or `or' instruction where rs1 is the same as rsd, and which has the i bit set? */ if ((opcode->match == 0x80102000 || opcode->match == 0x80002000) /* (or) (add) */ && 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': case 'v': /* double/even */ case 'V': /* quad/multiple of 4 */ freg (insn.rs1); break; case 'f': case 'B': /* double/even */ case 'R': /* quad/multiple of 4 */ freg (insn.rs2); break; case 'g': case 'H': /* double/even */ case 'J': /* quad/multiple of 4 */ 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. FIXME: No longer true/relavant ??? 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 aliases, two "identical" instructions had better have the same opcode. This is a sanity check on the table. */ i = STRCMP (op0->name, op1->name); if (i) if (op0->flags & F_ALIAS) /* If they're both aliases, be arbitrary. */ return i; else 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; }