453 lines
11 KiB
C
453 lines
11 KiB
C
/* 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. */
|
|
|
|
#ifndef lint
|
|
static char rcsid[] = "$Id: sparc-pinsn.c,v 1.2 1993/08/02 17:40:22 mycroft Exp $";
|
|
#endif /* not lint */
|
|
|
|
#include <stdio.h>
|
|
|
|
#include "defs.h"
|
|
#include "param.h"
|
|
#include "symtab.h"
|
|
#include "sparc-opcode.h"
|
|
|
|
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
|
|
&& (opcode->delayed))
|
|
return 1;
|
|
}
|
|
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 (index (opcode->args, 'S') != 0)
|
|
/* Reject the special case for `set'.
|
|
The real `sethi' will match. */
|
|
continue;
|
|
if (insn.rs1 != insn.rd
|
|
&& index (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 = read_memory (memaddr - 4,
|
|
&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 = read_memory (memaddr - 8,
|
|
&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);
|
|
}
|
|
}
|
|
|
|
fprintf_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\", %#.8x, %#.8x\n",
|
|
op0->name, match0, lose0);
|
|
op0->lose &= ~op0->match;
|
|
lose0 = op0->lose;
|
|
}
|
|
|
|
if (match1 & lose1)
|
|
{
|
|
fprintf (stderr, "Internal error: bad sparc-opcode.h: \"%s\", %#.8x, %#.8x\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. */
|
|
{
|
|
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 *) index(op0->args, '+');
|
|
char *p1 = (char *) index(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;
|
|
}
|