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

Make the Thumb2 disassembler handle more 32-bit instructions:

  A5.3.3 Data processing (plain binary immediate)

These use mostly twelve bit literals, but there are also bitfield
and saturated add primitives.


git-svn-id: svn://svn.berlios.de/openocd/trunk@2534 b42882b7-edfa-0310-969c-e2dbd0fdcd60
This commit is contained in:
zwelch 2009-07-15 23:48:21 +00:00
parent 0165ae4405
commit f163d0009d
1 changed files with 99 additions and 0 deletions
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99
src/target/arm_disassembler.c
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@ -2671,6 +2671,101 @@ static int t2ev_data_mod_immed(uint32_t opcode, uint32_t address,
return ERROR_OK; return ERROR_OK;
} }
static int t2ev_data_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;
bool add = false;
bool is_signed = false;
immed = (opcode & 0x0ff) | ((opcode & 0x7000) >> 12);
if (opcode & (1 << 27))
immed |= (1 << 11);
switch ((opcode >> 20) & 0x1f) {
case 0:
if (rn == 0xf) {
add = true;
goto do_adr;
}
mnemonic = "ADD.W";
break;
case 4:
mnemonic = "MOV.W";
break;
case 0x0a:
if (rn == 0xf)
goto do_adr;
mnemonic = "SUB.W";
break;
case 0x0c:
/* move constant to top 16 bits of register */
immed |= (opcode >> 4) & 0xf000;
sprintf(cp, "MOVT\tr%d, #%d\t; %#4.4x", rn, immed, immed);
return ERROR_OK;
case 0x10:
case 0x12:
is_signed = true;
case 0x18:
case 0x1a:
/* signed/unsigned saturated add */
immed = (opcode >> 6) & 0x03;
immed |= (opcode >> 10) & 0x1c;
sprintf(cp, "%sSAT\tr%d, #%d, r%d, %s #%d\t",
is_signed ? "S" : "U",
rd, (opcode & 0x1f) + 1, rn,
(opcode & (1 << 21)) ? "ASR" : "LSL",
immed ? immed : 32);
return ERROR_OK;
case 0x14:
is_signed = true;
/* FALLTHROUGH */
case 0x1c:
/* signed/unsigned bitfield extract */
immed = (opcode >> 6) & 0x03;
immed |= (opcode >> 10) & 0x1c;
sprintf(cp, "%sBFX\tr%d, r%d, #%d, #%d\t",
is_signed ? "S" : "U",
rd, rn, immed,
(opcode & 0x1f) + 1);
return ERROR_OK;
case 0x16:
immed = (opcode >> 6) & 0x03;
immed |= (opcode >> 10) & 0x1c;
if (rn == 0xf) /* bitfield clear */
sprintf(cp, "BFC\tr%d, #%d, #%d\t",
rd, immed,
(opcode & 0x1f) + 1 - immed);
else /* bitfield insert */
sprintf(cp, "BFI\tr%d, r%d, #%d, #%d\t",
rd, rn, immed,
(opcode & 0x1f) + 1 - immed);
return ERROR_OK;
default:
return ERROR_INVALID_ARGUMENTS;
}
sprintf(cp, "%s\tr%d, r%d, #%d\t; %#3.3x", mnemonic,
rd, rn, immed, immed);
return ERROR_OK;
do_adr:
address &= ~0x03;
address += 4;
if (add)
address += immed;
else
address -= immed;
/* REVISIT "ADD/SUB Rd, PC, #const ; 0x..." might be better;
* not hiding the pc-relative stuff will sometimes be useful.
*/
sprintf(cp, "ADR.W\tr%d, %#8.8" PRIx32, rd, address);
return ERROR_OK;
}
/* /*
* REVISIT for Thumb2 instructions, instruction->type and friends aren't * REVISIT for Thumb2 instructions, instruction->type and friends aren't
* always set. That means eventual arm_simulate_step() support for Thumb2 * always set. That means eventual arm_simulate_step() support for Thumb2
@ -2722,6 +2817,10 @@ int thumb2_opcode(target_t *target, uint32_t address, arm_instruction_t *instruc
if ((opcode & 0x1a008000) == 0x10000000) if ((opcode & 0x1a008000) == 0x10000000)
retval = t2ev_data_mod_immed(opcode, address, instruction, cp); retval = t2ev_data_mod_immed(opcode, address, instruction, cp);
/* ARMv7-M: A5.3.3 Data processing (plain binary immediate) */
else if ((opcode & 0x1a008000) == 0x12000000)
retval = t2ev_data_immed(opcode, address, instruction, cp);
/* ARMv7-M: A5.3.4 Branches and miscellaneous control */ /* ARMv7-M: A5.3.4 Branches and miscellaneous control */
else if ((opcode & 0x18008000) == 0x10008000) else if ((opcode & 0x18008000) == 0x10008000)
retval = t2ev_b_misc(opcode, address, instruction, cp); retval = t2ev_b_misc(opcode, address, instruction, cp);