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Disassembler: ARMv6K REX instructions

This commit is contained in:
aroulin 2015-08-06 13:55:56 +02:00
parent 5d81a2fd48
commit 3425cfe54a
2 changed files with 97 additions and 6 deletions

View File

@ -38,6 +38,7 @@ static const char *opcode_names[] = {
"blx",
"bx",
"cdp",
"clrex",
"clz",
"cmn",
"cmp",
@ -47,6 +48,10 @@ static const char *opcode_names[] = {
"ldr",
"ldrb",
"ldrbt",
"ldrex",
"ldrexb",
"ldrexd",
"ldrexh",
"ldrh",
"ldrsb",
"ldrsh",
@ -73,6 +78,10 @@ static const char *opcode_names[] = {
"str",
"strb",
"strbt",
"strex",
"strexb",
"strexd",
"strexh",
"strh",
"strt",
"sub",
@ -178,6 +187,8 @@ std::string ARM_Disasm::Disassemble(uint32_t addr, uint32_t insn)
return DisassembleBX(insn);
case OP_CDP:
return "cdp";
case OP_CLREX:
return "clrex";
case OP_CLZ:
return DisassembleCLZ(insn);
case OP_LDC:
@ -194,6 +205,15 @@ std::string ARM_Disasm::Disassemble(uint32_t addr, uint32_t insn)
case OP_STRBT:
case OP_STRT:
return DisassembleMem(insn);
case OP_LDREX:
case OP_LDREXB:
case OP_LDREXD:
case OP_LDREXH:
case OP_STREX:
case OP_STREXB:
case OP_STREXD:
case OP_STREXH:
return DisassembleREX(opcode, insn);
case OP_LDRH:
case OP_LDRSB:
case OP_LDRSH:
@ -687,6 +707,36 @@ std::string ARM_Disasm::DisassemblePLD(uint32_t insn)
}
}
std::string ARM_Disasm::DisassembleREX(Opcode opcode, uint32_t insn) {
uint32_t rn = BITS(insn, 16, 19);
uint32_t rd = BITS(insn, 12, 15);
uint32_t rt = BITS(insn, 0, 3);
uint32_t cond = BITS(insn, 28, 31);
switch (opcode) {
case OP_STREX:
case OP_STREXB:
case OP_STREXH:
return Common::StringFromFormat("%s%s\tr%d, r%d, [r%d]", opcode_names[opcode],
cond_to_str(cond), rd, rt, rn);
case OP_STREXD:
return Common::StringFromFormat("%s%s\tr%d, r%d, r%d, [r%d]", opcode_names[opcode],
cond_to_str(cond), rd, rt, rt + 1, rn);
// for LDREX instructions, rd corresponds to Rt from reference manual
case OP_LDREX:
case OP_LDREXB:
case OP_LDREXH:
return Common::StringFromFormat("%s%s\tr%d, [r%d]", opcode_names[opcode],
cond_to_str(cond), rd, rn);
case OP_LDREXD:
return Common::StringFromFormat("%s%s\tr%d, r%d, [r%d]", opcode_names[opcode],
cond_to_str(cond), rd, rd + 1, rn);
default:
return opcode_names[OP_UNDEFINED];
}
}
std::string ARM_Disasm::DisassembleSWI(uint32_t insn)
{
uint8_t cond = (insn >> 28) & 0xf;
@ -739,12 +789,9 @@ Opcode ARM_Disasm::Decode00(uint32_t insn) {
}
uint32_t bits7_4 = (insn >> 4) & 0xf;
if (bits7_4 == 0x9) {
if ((insn & 0x0ff00ff0) == 0x01000090) {
// Swp instruction
uint8_t bit22 = (insn >> 22) & 0x1;
if (bit22)
return OP_SWPB;
return OP_SWP;
uint32_t bit24 = BIT(insn, 24);
if (bit24) {
return DecodeSyncPrimitive(insn);
}
// One of the multiply instructions
return DecodeMUL(insn);
@ -778,6 +825,10 @@ Opcode ARM_Disasm::Decode01(uint32_t insn) {
// Pre-load
return OP_PLD;
}
if (insn == 0xf57ff01f) {
// Clear-Exclusive
return OP_CLREX;
}
if (is_load) {
if (is_byte) {
// Load byte
@ -868,6 +919,35 @@ Opcode ARM_Disasm::Decode11(uint32_t insn) {
return OP_MCR;
}
Opcode ARM_Disasm::DecodeSyncPrimitive(uint32_t insn) {
uint32_t op = BITS(insn, 20, 23);
uint32_t bit22 = BIT(insn, 22);
switch (op) {
case 0x0:
if (bit22)
return OP_SWPB;
return OP_SWP;
case 0x8:
return OP_STREX;
case 0x9:
return OP_LDREX;
case 0xA:
return OP_STREXD;
case 0xB:
return OP_LDREXD;
case 0xC:
return OP_STREXB;
case 0xD:
return OP_LDREXB;
case 0xE:
return OP_STREXH;
case 0xF:
return OP_LDREXH;
default:
return OP_UNDEFINED;
}
}
Opcode ARM_Disasm::DecodeMUL(uint32_t insn) {
uint8_t bit24 = (insn >> 24) & 0x1;
if (bit24 != 0) {

View File

@ -20,6 +20,7 @@ enum Opcode {
OP_BLX,
OP_BX,
OP_CDP,
OP_CLREX,
OP_CLZ,
OP_CMN,
OP_CMP,
@ -29,6 +30,10 @@ enum Opcode {
OP_LDR,
OP_LDRB,
OP_LDRBT,
OP_LDREX,
OP_LDREXB,
OP_LDREXD,
OP_LDREXH,
OP_LDRH,
OP_LDRSB,
OP_LDRSH,
@ -55,6 +60,10 @@ enum Opcode {
OP_STR,
OP_STRB,
OP_STRBT,
OP_STREX,
OP_STREXB,
OP_STREXD,
OP_STREXH,
OP_STRH,
OP_STRT,
OP_SUB,
@ -122,6 +131,7 @@ class ARM_Disasm {
static Opcode Decode01(uint32_t insn);
static Opcode Decode10(uint32_t insn);
static Opcode Decode11(uint32_t insn);
static Opcode DecodeSyncPrimitive(uint32_t insn);
static Opcode DecodeMUL(uint32_t insn);
static Opcode DecodeMSRImmAndHints(uint32_t insn);
static Opcode DecodeLDRH(uint32_t insn);
@ -143,6 +153,7 @@ class ARM_Disasm {
static std::string DisassembleMSR(uint32_t insn);
static std::string DisassembleNoOperands(Opcode opcode, uint32_t insn);
static std::string DisassemblePLD(uint32_t insn);
static std::string DisassembleREX(Opcode opcode, uint32_t insn);
static std::string DisassembleSWI(uint32_t insn);
static std::string DisassembleSWP(Opcode opcode, uint32_t insn);
};