From 3425cfe54a46512a2ef35e5254c2d32e14ace69a Mon Sep 17 00:00:00 2001 From: aroulin Date: Thu, 6 Aug 2015 13:55:56 +0200 Subject: Disassembler: ARMv6K REX instructions --- src/core/arm/disassembler/arm_disasm.cpp | 92 +++++++++++++++++++++++++++++--- src/core/arm/disassembler/arm_disasm.h | 11 ++++ 2 files changed, 97 insertions(+), 6 deletions(-) (limited to 'src') diff --git a/src/core/arm/disassembler/arm_disasm.cpp b/src/core/arm/disassembler/arm_disasm.cpp index bb87043a..8eec64d4 100644 --- a/src/core/arm/disassembler/arm_disasm.cpp +++ b/src/core/arm/disassembler/arm_disasm.cpp @@ -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) { diff --git a/src/core/arm/disassembler/arm_disasm.h b/src/core/arm/disassembler/arm_disasm.h index a4e4adf2..d04fd21e 100644 --- a/src/core/arm/disassembler/arm_disasm.h +++ b/src/core/arm/disassembler/arm_disasm.h @@ -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); }; -- cgit v1.2.3