From 0165ae44053f3eb7a94ab88dee2e01b412bf5517 Mon Sep 17 00:00:00 2001 From: zwelch Date: Wed, 15 Jul 2009 23:48:16 +0000 Subject: David Brownell : 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 --- src/target/arm_disassembler.c | 144 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 143 insertions(+), 1 deletion(-) (limited to 'src/target') diff --git a/src/target/arm_disassembler.c b/src/target/arm_disassembler.c index 69d5de87..25b27378 100644 --- a/src/target/arm_disassembler.c +++ b/src/target/arm_disassembler.c @@ -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 */ -- cgit v1.2.3