Lime3DS/src/core/arm/disassembler/arm_disasm.cpp

1345 lines
39 KiB
C++

// Copyright 2006 The Android Open Source Project
#include <string>
#include <unordered_set>
#include "common/common_types.h"
#include "common/string_util.h"
#include "core/arm/disassembler/arm_disasm.h"
#include "core/arm/skyeye_common/armsupp.h"
static const char* cond_names[] = {"eq", "ne", "cs", "cc", "mi", "pl", "vs", "vc",
"hi", "ls", "ge", "lt", "gt", "le", "", "RESERVED"};
static const char* opcode_names[] = {
"invalid", "undefined", "adc", "add", "and", "b", "bl", "bic",
"bkpt", "blx", "bx", "cdp", "clrex", "clz", "cmn", "cmp",
"eor", "ldc", "ldm", "ldr", "ldrb", "ldrbt", "ldrex", "ldrexb",
"ldrexd", "ldrexh", "ldrh", "ldrsb", "ldrsh", "ldrt", "mcr", "mla",
"mov", "mrc", "mrs", "msr", "mul", "mvn", "nop", "orr",
"pkh", "pld", "qadd16", "qadd8", "qasx", "qsax", "qsub16", "qsub8",
"rev", "rev16", "revsh", "rsb", "rsc", "sadd16", "sadd8", "sasx",
"sbc", "sel", "sev", "shadd16", "shadd8", "shasx", "shsax", "shsub16",
"shsub8", "smlad", "smlal", "smlald", "smlsd", "smlsld", "smmla", "smmls",
"smmul", "smuad", "smull", "smusd", "ssat", "ssat16", "ssax", "ssub16",
"ssub8", "stc", "stm", "str", "strb", "strbt", "strex", "strexb",
"strexd", "strexh", "strh", "strt", "sub", "swi", "swp", "swpb",
"sxtab", "sxtab16", "sxtah", "sxtb", "sxtb16", "sxth", "teq", "tst",
"uadd16", "uadd8", "uasx", "uhadd16", "uhadd8", "uhasx", "uhsax", "uhsub16",
"uhsub8", "umlal", "umull", "uqadd16", "uqadd8", "uqasx", "uqsax", "uqsub16",
"uqsub8", "usad8", "usada8", "usat", "usat16", "usax", "usub16", "usub8",
"uxtab", "uxtab16", "uxtah", "uxtb", "uxtb16", "uxth", "wfe", "wfi",
"yield",
"undefined", "adc", "add", "and", "asr", "b", "bic", "bkpt",
"bl", "blx", "bx", "cmn", "cmp", "eor", "ldmia", "ldr",
"ldrb", "ldrh", "ldrsb", "ldrsh", "lsl", "lsr", "mov", "mul",
"mvn", "neg", "orr", "pop", "push", "ror", "sbc", "stmia",
"str", "strb", "strh", "sub", "swi", "tst",
nullptr};
// Indexed by the shift type (bits 6-5)
static const char* shift_names[] = {"LSL", "LSR", "ASR", "ROR"};
static const char* cond_to_str(u32 cond) {
return cond_names[cond];
}
std::string ARM_Disasm::Disassemble(u32 addr, u32 insn) {
Opcode opcode = Decode(insn);
switch (opcode) {
case OP_INVALID:
return "Invalid";
case OP_UNDEFINED:
return "Undefined";
case OP_ADC:
case OP_ADD:
case OP_AND:
case OP_BIC:
case OP_CMN:
case OP_CMP:
case OP_EOR:
case OP_MOV:
case OP_MVN:
case OP_ORR:
case OP_RSB:
case OP_RSC:
case OP_SBC:
case OP_SUB:
case OP_TEQ:
case OP_TST:
return DisassembleALU(opcode, insn);
case OP_B:
case OP_BL:
return DisassembleBranch(addr, opcode, insn);
case OP_BKPT:
return DisassembleBKPT(insn);
case OP_BLX:
// not supported yet
break;
case OP_BX:
return DisassembleBX(insn);
case OP_CDP:
return "cdp";
case OP_CLREX:
return "clrex";
case OP_CLZ:
return DisassembleCLZ(insn);
case OP_LDC:
return "ldc";
case OP_LDM:
case OP_STM:
return DisassembleMemblock(opcode, insn);
case OP_LDR:
case OP_LDRB:
case OP_LDRBT:
case OP_LDRT:
case OP_STR:
case OP_STRB:
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:
case OP_STRH:
return DisassembleMemHalf(insn);
case OP_MCR:
case OP_MRC:
return DisassembleMCR(opcode, insn);
case OP_MLA:
return DisassembleMLA(opcode, insn);
case OP_MRS:
return DisassembleMRS(insn);
case OP_MSR:
return DisassembleMSR(insn);
case OP_MUL:
return DisassembleMUL(opcode, insn);
case OP_NOP:
case OP_SEV:
case OP_WFE:
case OP_WFI:
case OP_YIELD:
return DisassembleNoOperands(opcode, insn);
case OP_PKH:
return DisassemblePKH(insn);
case OP_PLD:
return DisassemblePLD(insn);
case OP_QADD16:
case OP_QADD8:
case OP_QASX:
case OP_QSAX:
case OP_QSUB16:
case OP_QSUB8:
case OP_SADD16:
case OP_SADD8:
case OP_SASX:
case OP_SHADD16:
case OP_SHADD8:
case OP_SHASX:
case OP_SHSAX:
case OP_SHSUB16:
case OP_SHSUB8:
case OP_SSAX:
case OP_SSUB16:
case OP_SSUB8:
case OP_UADD16:
case OP_UADD8:
case OP_UASX:
case OP_UHADD16:
case OP_UHADD8:
case OP_UHASX:
case OP_UHSAX:
case OP_UHSUB16:
case OP_UHSUB8:
case OP_UQADD16:
case OP_UQADD8:
case OP_UQASX:
case OP_UQSAX:
case OP_UQSUB16:
case OP_UQSUB8:
case OP_USAX:
case OP_USUB16:
case OP_USUB8:
return DisassembleParallelAddSub(opcode, insn);
case OP_REV:
case OP_REV16:
case OP_REVSH:
return DisassembleREV(opcode, insn);
case OP_SEL:
return DisassembleSEL(insn);
case OP_SMLAD:
case OP_SMLALD:
case OP_SMLSD:
case OP_SMLSLD:
case OP_SMMLA:
case OP_SMMLS:
case OP_SMMUL:
case OP_SMUAD:
case OP_SMUSD:
case OP_USAD8:
case OP_USADA8:
return DisassembleMediaMulDiv(opcode, insn);
case OP_SSAT:
case OP_SSAT16:
case OP_USAT:
case OP_USAT16:
return DisassembleSAT(opcode, insn);
case OP_STC:
return "stc";
case OP_SWI:
return DisassembleSWI(insn);
case OP_SWP:
case OP_SWPB:
return DisassembleSWP(opcode, insn);
case OP_SXTAB:
case OP_SXTAB16:
case OP_SXTAH:
case OP_SXTB:
case OP_SXTB16:
case OP_SXTH:
case OP_UXTAB:
case OP_UXTAB16:
case OP_UXTAH:
case OP_UXTB:
case OP_UXTB16:
case OP_UXTH:
return DisassembleXT(opcode, insn);
case OP_UMLAL:
case OP_UMULL:
case OP_SMLAL:
case OP_SMULL:
return DisassembleUMLAL(opcode, insn);
default:
return "Error";
}
return nullptr;
}
std::string ARM_Disasm::DisassembleALU(Opcode opcode, u32 insn) {
static const u8 kNoOperand1 = 1;
static const u8 kNoDest = 2;
static const u8 kNoSbit = 4;
std::string rn_str;
std::string rd_str;
u8 flags = 0;
u8 cond = (insn >> 28) & 0xf;
u8 is_immed = (insn >> 25) & 0x1;
u8 bit_s = (insn >> 20) & 1;
u8 rn = (insn >> 16) & 0xf;
u8 rd = (insn >> 12) & 0xf;
u8 immed = insn & 0xff;
const char* opname = opcode_names[opcode];
switch (opcode) {
case OP_CMN:
case OP_CMP:
case OP_TEQ:
case OP_TST:
flags = kNoDest | kNoSbit;
break;
case OP_MOV:
case OP_MVN:
flags = kNoOperand1;
break;
default:
break;
}
// The "mov" instruction ignores the first operand (rn).
rn_str[0] = 0;
if ((flags & kNoOperand1) == 0) {
rn_str = Common::StringFromFormat("r%d, ", rn);
}
// The following instructions do not write the result register (rd):
// tst, teq, cmp, cmn.
rd_str[0] = 0;
if ((flags & kNoDest) == 0) {
rd_str = Common::StringFromFormat("r%d, ", rd);
}
const char* sbit_str = "";
if (bit_s && !(flags & kNoSbit))
sbit_str = "s";
if (is_immed) {
return Common::StringFromFormat("%s%s%s\t%s%s#%u ; 0x%x", opname, cond_to_str(cond),
sbit_str, rd_str.c_str(), rn_str.c_str(), immed, immed);
}
u8 shift_is_reg = (insn >> 4) & 1;
u8 rotate = (insn >> 8) & 0xf;
u8 rm = insn & 0xf;
u8 shift_type = (insn >> 5) & 0x3;
u8 rs = (insn >> 8) & 0xf;
u8 shift_amount = (insn >> 7) & 0x1f;
u32 rotated_val = immed;
u8 rotate2 = rotate << 1;
rotated_val = (rotated_val >> rotate2) | (rotated_val << (32 - rotate2));
if (!shift_is_reg && shift_type == 0 && shift_amount == 0) {
return Common::StringFromFormat("%s%s%s\t%s%sr%d", opname, cond_to_str(cond), sbit_str,
rd_str.c_str(), rn_str.c_str(), rm);
}
const char* shift_name = shift_names[shift_type];
if (shift_is_reg) {
return Common::StringFromFormat("%s%s%s\t%s%sr%d, %s r%d", opname, cond_to_str(cond),
sbit_str, rd_str.c_str(), rn_str.c_str(), rm, shift_name,
rs);
}
if (shift_amount == 0) {
if (shift_type == 3) {
return Common::StringFromFormat("%s%s%s\t%s%sr%d, RRX", opname, cond_to_str(cond),
sbit_str, rd_str.c_str(), rn_str.c_str(), rm);
}
shift_amount = 32;
}
return Common::StringFromFormat("%s%s%s\t%s%sr%d, %s #%u", opname, cond_to_str(cond), sbit_str,
rd_str.c_str(), rn_str.c_str(), rm, shift_name, shift_amount);
}
std::string ARM_Disasm::DisassembleBranch(u32 addr, Opcode opcode, u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u32 offset = insn & 0xffffff;
// Sign-extend the 24-bit offset
if ((offset >> 23) & 1)
offset |= 0xff000000;
// Pre-compute the left-shift and the prefetch offset
offset <<= 2;
offset += 8;
addr += offset;
const char* opname = opcode_names[opcode];
return Common::StringFromFormat("%s%s\t0x%x", opname, cond_to_str(cond), addr);
}
std::string ARM_Disasm::DisassembleBX(u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 rn = insn & 0xf;
return Common::StringFromFormat("bx%s\tr%d", cond_to_str(cond), rn);
}
std::string ARM_Disasm::DisassembleBKPT(u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u32 immed = (((insn >> 8) & 0xfff) << 4) | (insn & 0xf);
return Common::StringFromFormat("bkpt%s\t#%d", cond_to_str(cond), immed);
}
std::string ARM_Disasm::DisassembleCLZ(u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 rd = (insn >> 12) & 0xf;
u8 rm = insn & 0xf;
return Common::StringFromFormat("clz%s\tr%d, r%d", cond_to_str(cond), rd, rm);
}
std::string ARM_Disasm::DisassembleMediaMulDiv(Opcode opcode, u32 insn) {
u32 cond = BITS(insn, 28, 31);
u32 rd = BITS(insn, 16, 19);
u32 ra = BITS(insn, 12, 15);
u32 rm = BITS(insn, 8, 11);
u32 m = BIT(insn, 5);
u32 rn = BITS(insn, 0, 3);
std::string cross = "";
if (m) {
if (opcode == OP_SMMLA || opcode == OP_SMMUL || opcode == OP_SMMLS)
cross = "r";
else
cross = "x";
}
std::string ext_reg = "";
std::unordered_set<Opcode, std::hash<int>> with_ext_reg = {OP_SMLAD, OP_SMLSD, OP_SMMLA,
OP_SMMLS, OP_USADA8};
if (with_ext_reg.find(opcode) != with_ext_reg.end())
ext_reg = Common::StringFromFormat(", r%u", ra);
std::string rd_low = "";
if (opcode == OP_SMLALD || opcode == OP_SMLSLD)
rd_low = Common::StringFromFormat("r%u, ", ra);
return Common::StringFromFormat("%s%s%s\t%sr%u, r%u, r%u%s", opcode_names[opcode],
cross.c_str(), cond_to_str(cond), rd_low.c_str(), rd, rn, rm,
ext_reg.c_str());
}
std::string ARM_Disasm::DisassembleMemblock(Opcode opcode, u32 insn) {
std::string tmp_list;
u8 cond = (insn >> 28) & 0xf;
u8 write_back = (insn >> 21) & 0x1;
u8 bit_s = (insn >> 22) & 0x1;
u8 is_up = (insn >> 23) & 0x1;
u8 is_pre = (insn >> 24) & 0x1;
u8 rn = (insn >> 16) & 0xf;
u16 reg_list = insn & 0xffff;
const char* opname = opcode_names[opcode];
const char* bang = "";
if (write_back)
bang = "!";
const char* carret = "";
if (bit_s)
carret = "^";
const char* comma = "";
tmp_list[0] = 0;
for (int ii = 0; ii < 16; ++ii) {
if (reg_list & (1 << ii)) {
tmp_list += Common::StringFromFormat("%sr%d", comma, ii);
comma = ",";
}
}
const char* addr_mode = "";
if (is_pre) {
if (is_up) {
addr_mode = "ib";
} else {
addr_mode = "db";
}
} else {
if (is_up) {
addr_mode = "ia";
} else {
addr_mode = "da";
}
}
return Common::StringFromFormat("%s%s%s\tr%d%s, {%s}%s", opname, cond_to_str(cond), addr_mode,
rn, bang, tmp_list.c_str(), carret);
}
std::string ARM_Disasm::DisassembleMem(u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 is_reg = (insn >> 25) & 0x1;
u8 is_load = (insn >> 20) & 0x1;
u8 write_back = (insn >> 21) & 0x1;
u8 is_byte = (insn >> 22) & 0x1;
u8 is_up = (insn >> 23) & 0x1;
u8 is_pre = (insn >> 24) & 0x1;
u8 rn = (insn >> 16) & 0xf;
u8 rd = (insn >> 12) & 0xf;
u16 offset = insn & 0xfff;
const char* opname = "ldr";
if (!is_load)
opname = "str";
const char* bang = "";
if (write_back)
bang = "!";
const char* minus = "";
if (is_up == 0)
minus = "-";
const char* byte = "";
if (is_byte)
byte = "b";
if (is_reg == 0) {
if (is_pre) {
if (offset == 0) {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d]", opname, cond_to_str(cond),
byte, rd, rn);
} else {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d, #%s%u]%s", opname,
cond_to_str(cond), byte, rd, rn, minus, offset,
bang);
}
} else {
const char* transfer = "";
if (write_back)
transfer = "t";
return Common::StringFromFormat("%s%s%s%s\tr%d, [r%d], #%s%u", opname,
cond_to_str(cond), byte, transfer, rd, rn, minus,
offset);
}
}
u8 rm = insn & 0xf;
u8 shift_type = (insn >> 5) & 0x3;
u8 shift_amount = (insn >> 7) & 0x1f;
const char* shift_name = shift_names[shift_type];
if (is_pre) {
if (shift_amount == 0) {
if (shift_type == 0) {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d, %sr%d]%s", opname,
cond_to_str(cond), byte, rd, rn, minus, rm, bang);
}
if (shift_type == 3) {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d, %sr%d, RRX]%s", opname,
cond_to_str(cond), byte, rd, rn, minus, rm, bang);
}
shift_amount = 32;
}
return Common::StringFromFormat("%s%s%s\tr%d, [r%d, %sr%d, %s #%u]%s", opname,
cond_to_str(cond), byte, rd, rn, minus, rm, shift_name,
shift_amount, bang);
}
const char* transfer = "";
if (write_back)
transfer = "t";
if (shift_amount == 0) {
if (shift_type == 0) {
return Common::StringFromFormat("%s%s%s%s\tr%d, [r%d], %sr%d", opname,
cond_to_str(cond), byte, transfer, rd, rn, minus, rm);
}
if (shift_type == 3) {
return Common::StringFromFormat("%s%s%s%s\tr%d, [r%d], %sr%d, RRX", opname,
cond_to_str(cond), byte, transfer, rd, rn, minus, rm);
}
shift_amount = 32;
}
return Common::StringFromFormat("%s%s%s%s\tr%d, [r%d], %sr%d, %s #%u", opname,
cond_to_str(cond), byte, transfer, rd, rn, minus, rm,
shift_name, shift_amount);
}
std::string ARM_Disasm::DisassembleMemHalf(u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 is_load = (insn >> 20) & 0x1;
u8 write_back = (insn >> 21) & 0x1;
u8 is_immed = (insn >> 22) & 0x1;
u8 is_up = (insn >> 23) & 0x1;
u8 is_pre = (insn >> 24) & 0x1;
u8 rn = (insn >> 16) & 0xf;
u8 rd = (insn >> 12) & 0xf;
u8 bits_65 = (insn >> 5) & 0x3;
u8 rm = insn & 0xf;
u8 offset = (((insn >> 8) & 0xf) << 4) | (insn & 0xf);
const char* opname = "ldr";
if (is_load == 0)
opname = "str";
const char* width = "";
if (bits_65 == 1)
width = "h";
else if (bits_65 == 2)
width = "sb";
else
width = "sh";
const char* bang = "";
if (write_back)
bang = "!";
const char* minus = "";
if (is_up == 0)
minus = "-";
if (is_immed) {
if (is_pre) {
if (offset == 0) {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d]", opname, cond_to_str(cond),
width, rd, rn);
} else {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d, #%s%u]%s", opname,
cond_to_str(cond), width, rd, rn, minus, offset,
bang);
}
} else {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d], #%s%u", opname, cond_to_str(cond),
width, rd, rn, minus, offset);
}
}
if (is_pre) {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d, %sr%d]%s", opname, cond_to_str(cond),
width, rd, rn, minus, rm, bang);
} else {
return Common::StringFromFormat("%s%s%s\tr%d, [r%d], %sr%d", opname, cond_to_str(cond),
width, rd, rn, minus, rm);
}
}
std::string ARM_Disasm::DisassembleMCR(Opcode opcode, u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 crn = (insn >> 16) & 0xf;
u8 crd = (insn >> 12) & 0xf;
u8 cpnum = (insn >> 8) & 0xf;
u8 opcode2 = (insn >> 5) & 0x7;
u8 crm = insn & 0xf;
const char* opname = opcode_names[opcode];
return Common::StringFromFormat("%s%s\t%d, 0, r%d, cr%d, cr%d, {%d}", opname, cond_to_str(cond),
cpnum, crd, crn, crm, opcode2);
}
std::string ARM_Disasm::DisassembleMLA(Opcode opcode, u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 rd = (insn >> 16) & 0xf;
u8 rn = (insn >> 12) & 0xf;
u8 rs = (insn >> 8) & 0xf;
u8 rm = insn & 0xf;
u8 bit_s = (insn >> 20) & 1;
const char* opname = opcode_names[opcode];
return Common::StringFromFormat("%s%s%s\tr%d, r%d, r%d, r%d", opname, cond_to_str(cond),
bit_s ? "s" : "", rd, rm, rs, rn);
}
std::string ARM_Disasm::DisassembleUMLAL(Opcode opcode, u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 rdhi = (insn >> 16) & 0xf;
u8 rdlo = (insn >> 12) & 0xf;
u8 rs = (insn >> 8) & 0xf;
u8 rm = insn & 0xf;
u8 bit_s = (insn >> 20) & 1;
const char* opname = opcode_names[opcode];
return Common::StringFromFormat("%s%s%s\tr%d, r%d, r%d, r%d", opname, cond_to_str(cond),
bit_s ? "s" : "", rdlo, rdhi, rm, rs);
}
std::string ARM_Disasm::DisassembleMUL(Opcode opcode, u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 rd = (insn >> 16) & 0xf;
u8 rs = (insn >> 8) & 0xf;
u8 rm = insn & 0xf;
u8 bit_s = (insn >> 20) & 1;
const char* opname = opcode_names[opcode];
return Common::StringFromFormat("%s%s%s\tr%d, r%d, r%d", opname, cond_to_str(cond),
bit_s ? "s" : "", rd, rm, rs);
}
std::string ARM_Disasm::DisassembleMRS(u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 rd = (insn >> 12) & 0xf;
u8 ps = (insn >> 22) & 1;
return Common::StringFromFormat("mrs%s\tr%d, %s", cond_to_str(cond), rd, ps ? "spsr" : "cpsr");
}
std::string ARM_Disasm::DisassembleMSR(u32 insn) {
char flags[8];
int flag_index = 0;
u8 cond = (insn >> 28) & 0xf;
u8 is_immed = (insn >> 25) & 0x1;
u8 pd = (insn >> 22) & 1;
u8 mask = (insn >> 16) & 0xf;
if (mask & 1)
flags[flag_index++] = 'c';
if (mask & 2)
flags[flag_index++] = 'x';
if (mask & 4)
flags[flag_index++] = 's';
if (mask & 8)
flags[flag_index++] = 'f';
flags[flag_index] = 0;
if (is_immed) {
u32 immed = insn & 0xff;
u8 rotate = (insn >> 8) & 0xf;
u8 rotate2 = rotate << 1;
u32 rotated_val = (immed >> rotate2) | (immed << (32 - rotate2));
return Common::StringFromFormat("msr%s\t%s_%s, #0x%x", cond_to_str(cond),
pd ? "spsr" : "cpsr", flags, rotated_val);
}
u8 rm = insn & 0xf;
return Common::StringFromFormat("msr%s\t%s_%s, r%d", cond_to_str(cond), pd ? "spsr" : "cpsr",
flags, rm);
}
std::string ARM_Disasm::DisassembleNoOperands(Opcode opcode, u32 insn) {
u32 cond = BITS(insn, 28, 31);
return Common::StringFromFormat("%s%s", opcode_names[opcode], cond_to_str(cond));
}
std::string ARM_Disasm::DisassembleParallelAddSub(Opcode opcode, u32 insn) {
u32 cond = BITS(insn, 28, 31);
u32 rn = BITS(insn, 16, 19);
u32 rd = BITS(insn, 12, 15);
u32 rm = BITS(insn, 0, 3);
return Common::StringFromFormat("%s%s\tr%u, r%u, r%u", opcode_names[opcode], cond_to_str(cond),
rd, rn, rm);
}
std::string ARM_Disasm::DisassemblePKH(u32 insn) {
u32 cond = BITS(insn, 28, 31);
u32 rn = BITS(insn, 16, 19);
u32 rd = BITS(insn, 12, 15);
u32 imm5 = BITS(insn, 7, 11);
u32 tb = BIT(insn, 6);
u32 rm = BITS(insn, 0, 3);
std::string suffix = tb ? "tb" : "bt";
std::string shift = "";
if (tb && imm5 == 0)
imm5 = 32;
if (imm5 > 0) {
shift = tb ? ", ASR" : ", LSL";
shift += " #" + std::to_string(imm5);
}
return Common::StringFromFormat("pkh%s%s\tr%u, r%u, r%u%s", suffix.c_str(), cond_to_str(cond),
rd, rn, rm, shift.c_str());
}
std::string ARM_Disasm::DisassemblePLD(u32 insn) {
u8 is_reg = (insn >> 25) & 0x1;
u8 is_up = (insn >> 23) & 0x1;
u8 rn = (insn >> 16) & 0xf;
const char* minus = "";
if (is_up == 0)
minus = "-";
if (is_reg) {
u8 rm = insn & 0xf;
return Common::StringFromFormat("pld\t[r%d, %sr%d]", rn, minus, rm);
}
u16 offset = insn & 0xfff;
if (offset == 0) {
return Common::StringFromFormat("pld\t[r%d]", rn);
} else {
return Common::StringFromFormat("pld\t[r%d, #%s%u]", rn, minus, offset);
}
}
std::string ARM_Disasm::DisassembleREV(Opcode opcode, u32 insn) {
u32 cond = BITS(insn, 28, 31);
u32 rd = BITS(insn, 12, 15);
u32 rm = BITS(insn, 0, 3);
return Common::StringFromFormat("%s%s\tr%u, r%u", opcode_names[opcode], cond_to_str(cond), rd,
rm);
}
std::string ARM_Disasm::DisassembleREX(Opcode opcode, u32 insn) {
u32 rn = BITS(insn, 16, 19);
u32 rd = BITS(insn, 12, 15);
u32 rt = BITS(insn, 0, 3);
u32 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::DisassembleSAT(Opcode opcode, u32 insn) {
u32 cond = BITS(insn, 28, 31);
u32 sat_imm = BITS(insn, 16, 20);
u32 rd = BITS(insn, 12, 15);
u32 imm5 = BITS(insn, 7, 11);
u32 sh = BIT(insn, 6);
u32 rn = BITS(insn, 0, 3);
std::string shift_part = "";
bool opcode_has_shift = (opcode == OP_SSAT) || (opcode == OP_USAT);
if (opcode_has_shift && !(sh == 0 && imm5 == 0)) {
if (sh == 0)
shift_part += ", LSL #";
else
shift_part += ", ASR #";
if (imm5 == 0)
imm5 = 32;
shift_part += std::to_string(imm5);
}
if (opcode == OP_SSAT || opcode == OP_SSAT16)
sat_imm++;
return Common::StringFromFormat("%s%s\tr%u, #%u, r%u%s", opcode_names[opcode],
cond_to_str(cond), rd, sat_imm, rn, shift_part.c_str());
}
std::string ARM_Disasm::DisassembleSEL(u32 insn) {
u32 cond = BITS(insn, 28, 31);
u32 rn = BITS(insn, 16, 19);
u32 rd = BITS(insn, 12, 15);
u32 rm = BITS(insn, 0, 3);
return Common::StringFromFormat("%s%s\tr%u, r%u, r%u", opcode_names[OP_SEL], cond_to_str(cond),
rd, rn, rm);
}
std::string ARM_Disasm::DisassembleSWI(u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u32 sysnum = insn & 0x00ffffff;
return Common::StringFromFormat("swi%s 0x%x", cond_to_str(cond), sysnum);
}
std::string ARM_Disasm::DisassembleSWP(Opcode opcode, u32 insn) {
u8 cond = (insn >> 28) & 0xf;
u8 rn = (insn >> 16) & 0xf;
u8 rd = (insn >> 12) & 0xf;
u8 rm = insn & 0xf;
const char* opname = opcode_names[opcode];
return Common::StringFromFormat("%s%s\tr%d, r%d, [r%d]", opname, cond_to_str(cond), rd, rm, rn);
}
std::string ARM_Disasm::DisassembleXT(Opcode opcode, u32 insn) {
u32 cond = BITS(insn, 28, 31);
u32 rn = BITS(insn, 16, 19);
u32 rd = BITS(insn, 12, 15);
u32 rotate = BITS(insn, 10, 11);
u32 rm = BITS(insn, 0, 3);
std::string rn_part = "";
static std::unordered_set<Opcode, std::hash<int>> extend_with_add = {
OP_SXTAB, OP_SXTAB16, OP_SXTAH, OP_UXTAB, OP_UXTAB16, OP_UXTAH};
if (extend_with_add.find(opcode) != extend_with_add.end())
rn_part = ", r" + std::to_string(rn);
std::string rotate_part = "";
if (rotate != 0)
rotate_part = ", ROR #" + std::to_string(rotate << 3);
return Common::StringFromFormat("%s%s\tr%u%s, r%u%s", opcode_names[opcode], cond_to_str(cond),
rd, rn_part.c_str(), rm, rotate_part.c_str());
}
Opcode ARM_Disasm::Decode(u32 insn) {
u32 bits27_26 = (insn >> 26) & 0x3;
switch (bits27_26) {
case 0x0:
return Decode00(insn);
case 0x1:
return Decode01(insn);
case 0x2:
return Decode10(insn);
case 0x3:
return Decode11(insn);
}
return OP_INVALID;
}
Opcode ARM_Disasm::Decode00(u32 insn) {
u8 bit25 = (insn >> 25) & 0x1;
u8 bit4 = (insn >> 4) & 0x1;
if (bit25 == 0 && bit4 == 1) {
if ((insn & 0x0ffffff0) == 0x012fff10) {
// Bx instruction
return OP_BX;
}
if ((insn & 0x0ff000f0) == 0x01600010) {
// Clz instruction
return OP_CLZ;
}
if ((insn & 0xfff000f0) == 0xe1200070) {
// Bkpt instruction
return OP_BKPT;
}
u32 bits7_4 = (insn >> 4) & 0xf;
if (bits7_4 == 0x9) {
u32 bit24 = BIT(insn, 24);
if (bit24) {
return DecodeSyncPrimitive(insn);
}
// One of the multiply instructions
return DecodeMUL(insn);
}
u8 bit7 = (insn >> 7) & 0x1;
if (bit7 == 1) {
// One of the load/store halfword/byte instructions
return DecodeLDRH(insn);
}
}
u32 op1 = BITS(insn, 20, 24);
if (bit25 && (op1 == 0x12 || op1 == 0x16)) {
// One of the MSR (immediate) and hints instructions
return DecodeMSRImmAndHints(insn);
}
// One of the data processing instructions
return DecodeALU(insn);
}
Opcode ARM_Disasm::Decode01(u32 insn) {
u8 is_reg = (insn >> 25) & 0x1;
u8 bit4 = (insn >> 4) & 0x1;
if (is_reg == 1 && bit4 == 1)
return DecodeMedia(insn);
u8 is_load = (insn >> 20) & 0x1;
u8 is_byte = (insn >> 22) & 0x1;
if ((insn & 0xfd70f000) == 0xf550f000) {
// Pre-load
return OP_PLD;
}
if (insn == 0xf57ff01f) {
// Clear-Exclusive
return OP_CLREX;
}
if (is_load) {
if (is_byte) {
// Load byte
return OP_LDRB;
}
// Load word
return OP_LDR;
}
if (is_byte) {
// Store byte
return OP_STRB;
}
// Store word
return OP_STR;
}
Opcode ARM_Disasm::Decode10(u32 insn) {
u8 bit25 = (insn >> 25) & 0x1;
if (bit25 == 0) {
// LDM/STM
u8 is_load = (insn >> 20) & 0x1;
if (is_load)
return OP_LDM;
return OP_STM;
}
// Branch with link
if ((insn >> 24) & 1)
return OP_BL;
return OP_B;
}
Opcode ARM_Disasm::Decode11(u32 insn) {
u8 bit25 = (insn >> 25) & 0x1;
if (bit25 == 0) {
// LDC, SDC
u8 is_load = (insn >> 20) & 0x1;
if (is_load) {
// LDC
return OP_LDC;
}
// STC
return OP_STC;
}
u8 bit24 = (insn >> 24) & 0x1;
if (bit24 == 0x1) {
// SWI
return OP_SWI;
}
u8 bit4 = (insn >> 4) & 0x1;
u8 cpnum = (insn >> 8) & 0xf;
if (cpnum == 15) {
// Special case for coprocessor 15
u8 opcode = (insn >> 21) & 0x7;
if (bit4 == 0 || opcode != 0) {
// This is an unexpected bit pattern. Create an undefined
// instruction in case this is ever executed.
return OP_UNDEFINED;
}
// MRC, MCR
u8 is_mrc = (insn >> 20) & 0x1;
if (is_mrc)
return OP_MRC;
return OP_MCR;
}
if (bit4 == 0) {
// CDP
return OP_CDP;
}
// MRC, MCR
u8 is_mrc = (insn >> 20) & 0x1;
if (is_mrc)
return OP_MRC;
return OP_MCR;
}
Opcode ARM_Disasm::DecodeSyncPrimitive(u32 insn) {
u32 op = BITS(insn, 20, 23);
u32 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::DecodeParallelAddSub(u32 insn) {
u32 op1 = BITS(insn, 20, 21);
u32 op2 = BITS(insn, 5, 7);
u32 is_unsigned = BIT(insn, 22);
if (op1 == 0x0 || op2 == 0x5 || op2 == 0x6)
return OP_UNDEFINED;
// change op1 range from [1, 3] to range [0, 2]
op1--;
// change op2 range from [0, 4] U {7} to range [0, 5]
if (op2 == 0x7)
op2 = 0x5;
static std::vector<Opcode> opcodes = {
// op1 = 0
OP_SADD16, OP_UADD16, OP_SASX, OP_UASX, OP_SSAX, OP_USAX, OP_SSUB16, OP_USUB16, OP_SADD8,
OP_UADD8, OP_SSUB8, OP_USUB8,
// op1 = 1
OP_QADD16, OP_UQADD16, OP_QASX, OP_UQASX, OP_QSAX, OP_UQSAX, OP_QSUB16, OP_UQSUB16,
OP_QADD8, OP_UQADD8, OP_QSUB8, OP_UQSUB8,
// op1 = 2
OP_SHADD16, OP_UHADD16, OP_SHASX, OP_UHASX, OP_SHSAX, OP_UHSAX, OP_SHSUB16, OP_UHSUB16,
OP_SHADD8, OP_UHADD8, OP_SHSUB8, OP_UHSUB8};
u32 opcode_index = op1 * 12 + op2 * 2 + is_unsigned;
return opcodes[opcode_index];
}
Opcode ARM_Disasm::DecodePackingSaturationReversal(u32 insn) {
u32 op1 = BITS(insn, 20, 22);
u32 a = BITS(insn, 16, 19);
u32 op2 = BITS(insn, 5, 7);
switch (op1) {
case 0x0:
if (BIT(op2, 0) == 0)
return OP_PKH;
if (op2 == 0x3 && a != 0xf)
return OP_SXTAB16;
if (op2 == 0x3 && a == 0xf)
return OP_SXTB16;
if (op2 == 0x5)
return OP_SEL;
break;
case 0x2:
if (BIT(op2, 0) == 0)
return OP_SSAT;
if (op2 == 0x1)
return OP_SSAT16;
if (op2 == 0x3 && a != 0xf)
return OP_SXTAB;
if (op2 == 0x3 && a == 0xf)
return OP_SXTB;
break;
case 0x3:
if (op2 == 0x1)
return OP_REV;
if (BIT(op2, 0) == 0)
return OP_SSAT;
if (op2 == 0x3 && a != 0xf)
return OP_SXTAH;
if (op2 == 0x3 && a == 0xf)
return OP_SXTH;
if (op2 == 0x5)
return OP_REV16;
break;
case 0x4:
if (op2 == 0x3 && a != 0xf)
return OP_UXTAB16;
if (op2 == 0x3 && a == 0xf)
return OP_UXTB16;
break;
case 0x6:
if (BIT(op2, 0) == 0)
return OP_USAT;
if (op2 == 0x1)
return OP_USAT16;
if (op2 == 0x3 && a != 0xf)
return OP_UXTAB;
if (op2 == 0x3 && a == 0xf)
return OP_UXTB;
break;
case 0x7:
if (BIT(op2, 0) == 0)
return OP_USAT;
if (op2 == 0x3 && a != 0xf)
return OP_UXTAH;
if (op2 == 0x3 && a == 0xf)
return OP_UXTH;
if (op2 == 0x5)
return OP_REVSH;
break;
default:
break;
}
return OP_UNDEFINED;
}
Opcode ARM_Disasm::DecodeMUL(u32 insn) {
u8 bit24 = (insn >> 24) & 0x1;
if (bit24 != 0) {
// This is an unexpected bit pattern. Create an undefined
// instruction in case this is ever executed.
return OP_UNDEFINED;
}
u8 bit23 = (insn >> 23) & 0x1;
u8 bit22_U = (insn >> 22) & 0x1;
u8 bit21_A = (insn >> 21) & 0x1;
if (bit23 == 0) {
// 32-bit multiply
if (bit22_U != 0) {
// This is an unexpected bit pattern. Create an undefined
// instruction in case this is ever executed.
return OP_UNDEFINED;
}
if (bit21_A == 0)
return OP_MUL;
return OP_MLA;
}
// 64-bit multiply
if (bit22_U == 0) {
// Unsigned multiply long
if (bit21_A == 0)
return OP_UMULL;
return OP_UMLAL;
}
// Signed multiply long
if (bit21_A == 0)
return OP_SMULL;
return OP_SMLAL;
}
Opcode ARM_Disasm::DecodeMSRImmAndHints(u32 insn) {
u32 op = BIT(insn, 22);
u32 op1 = BITS(insn, 16, 19);
u32 op2 = BITS(insn, 0, 7);
if (op == 0 && op1 == 0) {
switch (op2) {
case 0x0:
return OP_NOP;
case 0x1:
return OP_YIELD;
case 0x2:
return OP_WFE;
case 0x3:
return OP_WFI;
case 0x4:
return OP_SEV;
default:
return OP_UNDEFINED;
}
}
return OP_MSR;
}
Opcode ARM_Disasm::DecodeMediaMulDiv(u32 insn) {
u32 op1 = BITS(insn, 20, 22);
u32 op2_h = BITS(insn, 6, 7);
u32 a = BITS(insn, 12, 15);
switch (op1) {
case 0x0:
if (op2_h == 0x0) {
if (a != 0xf)
return OP_SMLAD;
else
return OP_SMUAD;
} else if (op2_h == 0x1) {
if (a != 0xf)
return OP_SMLSD;
else
return OP_SMUSD;
}
break;
case 0x4:
if (op2_h == 0x0)
return OP_SMLALD;
else if (op2_h == 0x1)
return OP_SMLSLD;
break;
case 0x5:
if (op2_h == 0x0) {
if (a != 0xf)
return OP_SMMLA;
else
return OP_SMMUL;
} else if (op2_h == 0x3) {
return OP_SMMLS;
}
break;
default:
break;
}
return OP_UNDEFINED;
}
Opcode ARM_Disasm::DecodeMedia(u32 insn) {
u32 op1 = BITS(insn, 20, 24);
u32 rd = BITS(insn, 12, 15);
u32 op2 = BITS(insn, 5, 7);
switch (BITS(op1, 3, 4)) {
case 0x0:
// unsigned and signed parallel addition and subtraction
return DecodeParallelAddSub(insn);
case 0x1:
// Packing, unpacking, saturation, and reversal
return DecodePackingSaturationReversal(insn);
case 0x2:
// Signed multiply, signed and unsigned divide
return DecodeMediaMulDiv(insn);
case 0x3:
if (op2 == 0 && rd == 0xf)
return OP_USAD8;
if (op2 == 0 && rd != 0xf)
return OP_USADA8;
break;
default:
break;
}
return OP_UNDEFINED;
}
Opcode ARM_Disasm::DecodeLDRH(u32 insn) {
u8 is_load = (insn >> 20) & 0x1;
u8 bits_65 = (insn >> 5) & 0x3;
if (is_load) {
if (bits_65 == 0x1) {
// Load unsigned halfword
return OP_LDRH;
} else if (bits_65 == 0x2) {
// Load signed byte
return OP_LDRSB;
}
// Signed halfword
if (bits_65 != 0x3) {
// This is an unexpected bit pattern. Create an undefined
// instruction in case this is ever executed.
return OP_UNDEFINED;
}
// Load signed halfword
return OP_LDRSH;
}
// Store halfword
if (bits_65 != 0x1) {
// This is an unexpected bit pattern. Create an undefined
// instruction in case this is ever executed.
return OP_UNDEFINED;
}
// Store halfword
return OP_STRH;
}
Opcode ARM_Disasm::DecodeALU(u32 insn) {
u8 is_immed = (insn >> 25) & 0x1;
u8 opcode = (insn >> 21) & 0xf;
u8 bit_s = (insn >> 20) & 1;
u8 shift_is_reg = (insn >> 4) & 1;
u8 bit7 = (insn >> 7) & 1;
if (!is_immed && shift_is_reg && (bit7 != 0)) {
// This is an unexpected bit pattern. Create an undefined
// instruction in case this is ever executed.
return OP_UNDEFINED;
}
switch (opcode) {
case 0x0:
return OP_AND;
case 0x1:
return OP_EOR;
case 0x2:
return OP_SUB;
case 0x3:
return OP_RSB;
case 0x4:
return OP_ADD;
case 0x5:
return OP_ADC;
case 0x6:
return OP_SBC;
case 0x7:
return OP_RSC;
case 0x8:
if (bit_s)
return OP_TST;
return OP_MRS;
case 0x9:
if (bit_s)
return OP_TEQ;
return OP_MSR;
case 0xa:
if (bit_s)
return OP_CMP;
return OP_MRS;
case 0xb:
if (bit_s)
return OP_CMN;
return OP_MSR;
case 0xc:
return OP_ORR;
case 0xd:
return OP_MOV;
case 0xe:
return OP_BIC;
case 0xf:
return OP_MVN;
}
// Unreachable
return OP_INVALID;
}