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David Brownell <david-b@pacbell.net>: 

Make the Thumb2 disassembler handle more 32-bit instructions:

  A5.3.1 Data processing (modified immediate)

My small sample shows GCC likes to use many of these instructions.


git-svn-id: svn://svn.berlios.de/openocd/trunk@2533 b42882b7-edfa-0310-969c-e2dbd0fdcd60
__archive__
zwelch 2009-07-15 23:48:16 +00:00
parent 8b89224c6e
commit 0165ae4405
1 changed files with 143 additions and 1 deletions
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144
src/target/arm_disassembler.c
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@ -2532,6 +2532,144 @@ undef:
return ERROR_INVALID_ARGUMENTS;
}
static int t2ev_data_mod_immed(uint32_t opcode, uint32_t address,
arm_instruction_t *instruction, char *cp)
{
char *mnemonic = NULL;
int rn = (opcode >> 16) & 0xf;
int rd = (opcode >> 8) & 0xf;
unsigned immed = opcode & 0xff;
unsigned func;
bool one = false;
char *suffix = "";
/* ARMv7-M: A5.3.2 Modified immediate constants */
func = (opcode >> 11) & 0x0e;
if (immed & 0x80)
func |= 1;
if (opcode & (1 << 26))
func |= 0x10;
/* "Modified" immediates */
switch (func >> 1) {
case 0:
break;
case 2:
immed <<= 8;
/* FALLTHROUGH */
case 1:
immed += immed << 16;
break;
case 3:
immed += immed << 8;
immed += immed << 16;
break;
default:
immed |= 0x80;
immed = ror(immed, func);
}
if (opcode & (1 << 20))
suffix = "S";
switch ((opcode >> 21) & 0xf) {
case 0:
if (rd == 0xf) {
instruction->type = ARM_TST;
mnemonic = "TST";
one = true;
suffix = "";
rd = rn;
} else {
instruction->type = ARM_AND;
mnemonic = "AND";
}
break;
case 1:
instruction->type = ARM_BIC;
mnemonic = "BIC";
break;
case 2:
if (rn == 0xf) {
instruction->type = ARM_MOV;
mnemonic = "MOV";
one = true;
} else {
instruction->type = ARM_ORR;
mnemonic = "ORR";
}
break;
case 3:
if (rn == 0xf) {
instruction->type = ARM_MVN;
mnemonic = "MVN";
one = true;
} else {
// instruction->type = ARM_ORN;
mnemonic = "ORN";
}
break;
case 4:
if (rd == 0xf) {
instruction->type = ARM_TEQ;
mnemonic = "TEQ";
one = true;
suffix = "";
rd = rn;
} else {
instruction->type = ARM_EOR;
mnemonic = "EOR";
}
break;
case 8:
if (rd == 0xf) {
instruction->type = ARM_CMN;
mnemonic = "CMN";
one = true;
suffix = "";
rd = rn;
} else {
instruction->type = ARM_ADD;
mnemonic = "ADD";
}
break;
case 10:
instruction->type = ARM_ADC;
mnemonic = "ADC";
break;
case 11:
instruction->type = ARM_SBC;
mnemonic = "SBC";
break;
case 13:
if (rd == 0xf) {
instruction->type = ARM_CMP;
mnemonic = "CMP";
one = true;
suffix = "";
rd = rn;
} else {
instruction->type = ARM_SUB;
mnemonic = "SUB";
}
break;
case 14:
instruction->type = ARM_RSB;
mnemonic = "RSB";
break;
default:
return ERROR_INVALID_ARGUMENTS;
}
if (one)
sprintf(cp, "%s\tr%d, #%d\t; %#8.8x",
mnemonic, rd, immed, immed);
else
sprintf(cp, "%s%s\tr%d, r%d, #%d\t; %#8.8x",
mnemonic, suffix, rd, rn, immed, immed);
return ERROR_OK;
}
/*
* REVISIT for Thumb2 instructions, instruction->type and friends aren't
@ -2580,8 +2718,12 @@ int thumb2_opcode(target_t *target, uint32_t address, arm_instruction_t *instruc
cp = strchr(instruction->text, 0);
retval = ERROR_FAIL;
/* ARMv7-M: A5.3.1 Data processing (modified immediate) */
if ((opcode & 0x1a008000) == 0x10000000)
retval = t2ev_data_mod_immed(opcode, address, instruction, cp);
/* ARMv7-M: A5.3.4 Branches and miscellaneous control */
if ((opcode & 0x18008000) == 0x10008000)
else if ((opcode & 0x18008000) == 0x10008000)
retval = t2ev_b_misc(opcode, address, instruction, cp);
/* FIXME decode more 32-bit instructions */