From 3425cfe54a46512a2ef35e5254c2d32e14ace69a Mon Sep 17 00:00:00 2001
From: aroulin <andy.roulin@epfl.ch>
Date: Thu, 6 Aug 2015 13:55:56 +0200
Subject: [PATCH] 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(-)
diff --git a/src/core/arm/disassembler/arm_disasm.cpp b/src/core/arm/disassembler/arm_disasm.cpp
index bb87043a4..8eec64d48 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 a4e4adf2f..d04fd21eb 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);
};