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arm: move static variable ITBlock to cs_struct, so make arm code trul…
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…y thread-safe
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@aquynh
aquynh committed Dec 2, 2013
1 parent f1c2eee commit 7c7a8bc
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Showing 3 changed files with 45 additions and 46 deletions.
82 changes: 37 additions & 45 deletions arch/ARM/ARMDisassembler.c
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Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,7 @@
#include "../../MCRegisterInfo.h"
#include "../../LEB128.h"
#include "../../MCDisassembler.h"
#include "../../cs_priv.h"

#include "ARMDisassembler.h"

Expand All @@ -40,13 +41,7 @@
#define GET_INSTRINFO_ENUM
#include "ARMGenInstrInfo.inc"

typedef struct ITStatus {
//std_vector<unsigned char> ITStates;
unsigned char ITStates[128]; // FIXME
unsigned int size;
} ITStatus;

static bool ITStatus_push_back(ITStatus *it, char v)
static bool ITStatus_push_back(ARM_ITStatus *it, char v)
{
it->ITStates[it->size] = v;
it->size++;
Expand All @@ -55,22 +50,22 @@ static bool ITStatus_push_back(ITStatus *it, char v)
}

// Returns true if the current instruction is in an IT block
static bool ITStatus_instrInITBlock(ITStatus *it)
static bool ITStatus_instrInITBlock(ARM_ITStatus *it)
{
//return !ITStates.empty();
return (it->size > 0);
}

// Returns true if current instruction is the last instruction in an IT block
static bool ITStatus_instrLastInITBlock(ITStatus *it)
static bool ITStatus_instrLastInITBlock(ARM_ITStatus *it)
{
return (it->size == 1);
}

// Handles the condition code status of instructions in IT blocks

// Returns the condition code for instruction in IT block
static unsigned ITStatus_getITCC(ITStatus *it)
static unsigned ITStatus_getITCC(ARM_ITStatus *it)
{
unsigned CC = ARMCC_AL;
if (ITStatus_instrInITBlock(it))
Expand All @@ -80,7 +75,7 @@ static unsigned ITStatus_getITCC(ITStatus *it)
}

// Advances the IT block state to the next T or E
static void ITStatus_advanceITState(ITStatus *it)
static void ITStatus_advanceITState(ARM_ITStatus *it)
{
//ITStates.pop_back();
it->size--;
Expand All @@ -89,7 +84,7 @@ static void ITStatus_advanceITState(ITStatus *it)
// Called when decoding an IT instruction. Sets the IT state for the following
// instructions that for the IT block. Firstcond and Mask correspond to the
// fields in the IT instruction encoding.
static void ITStatus_setITState(ITStatus *it, char Firstcond, char Mask)
static void ITStatus_setITState(ARM_ITStatus *it, char Firstcond, char Mask)
{
// (3 - the number of trailing zeros) is the number of then / else.
unsigned CondBit0 = Firstcond & 1;
Expand All @@ -110,9 +105,6 @@ static void ITStatus_setITState(ITStatus *it, char Firstcond, char Mask)

/// ThumbDisassembler - Thumb disassembler for all Thumb platforms.

// FIXME: make this ITBlock private for each Disassembler handle
static ITStatus ITBlock;

static bool Check(DecodeStatus *Out, DecodeStatus In)
{
switch (In) {
Expand Down Expand Up @@ -423,12 +415,12 @@ void ARM_init(MCRegisterInfo *MRI)
0);
}

static DecodeStatus _ARM_getInstruction(MCInst *MI, unsigned char *code, size_t code_len,
static DecodeStatus _ARM_getInstruction(cs_struct *ud, MCInst *MI, unsigned char *code, size_t code_len,
uint16_t *Size, size_t Address)
{
uint8_t bytes[4];

ITBlock.size = 0;
ud->ITBlock.size = 0;

//assert(!(STI.getFeatureBits() & ARM_ModeThumb) &&
// "Asked to disassemble an ARM instruction but Subtarget is in Thumb mode!");
Expand Down Expand Up @@ -547,7 +539,7 @@ static void AddThumb1SBit(MCInst *MI, bool InITBlock)
// encoding, but rather get their predicates from IT context. We need
// to fix up the predicate operands using this context information as a
// post-pass.
static DecodeStatus AddThumbPredicate(MCInst *MI)
static DecodeStatus AddThumbPredicate(cs_struct *ud, MCInst *MI)
{
DecodeStatus S = MCDisassembler_Success;

Expand All @@ -566,7 +558,7 @@ static DecodeStatus AddThumbPredicate(MCInst *MI)
case ARM_tSETEND:
// Some instructions (mostly conditional branches) are not
// allowed in IT blocks.
if (ITStatus_instrInITBlock(&ITBlock))
if (ITStatus_instrInITBlock(&(ud->ITBlock)))
S = MCDisassembler_SoftFail;
else
return MCDisassembler_Success;
Expand All @@ -578,7 +570,7 @@ static DecodeStatus AddThumbPredicate(MCInst *MI)
// Some instructions (mostly unconditional branches) can
// only appears at the end of, or outside of, an IT.
//if (ITBlock.instrInITBlock() && !ITBlock.instrLastInITBlock())
if (ITStatus_instrInITBlock(&ITBlock) && !ITStatus_instrLastInITBlock(&ITBlock))
if (ITStatus_instrInITBlock(&(ud->ITBlock)) && !ITStatus_instrLastInITBlock(&(ud->ITBlock)))
S = MCDisassembler_SoftFail;
break;
default:
Expand All @@ -588,11 +580,11 @@ static DecodeStatus AddThumbPredicate(MCInst *MI)
// If we're in an IT block, base the predicate on that. Otherwise,
// assume a predicate of AL.
unsigned CC;
CC = ITStatus_getITCC(&ITBlock);
CC = ITStatus_getITCC(&(ud->ITBlock));
if (CC == 0xF)
CC = ARMCC_AL;
if (ITStatus_instrInITBlock(&ITBlock))
ITStatus_advanceITState(&ITBlock);
if (ITStatus_instrInITBlock(&(ud->ITBlock)))
ITStatus_advanceITState(&(ud->ITBlock));

MCOperandInfo *OpInfo = ARMInsts[MCInst_getOpcode(MI)].OpInfo;
unsigned short NumOps = ARMInsts[MCInst_getOpcode(MI)].NumOperands;
Expand Down Expand Up @@ -623,12 +615,12 @@ static DecodeStatus AddThumbPredicate(MCInst *MI)
// mode, the auto-generated decoder will give them an (incorrect)
// predicate operand. We need to rewrite these operands based on the IT
// context as a post-pass.
static void UpdateThumbVFPPredicate(MCInst *MI)
static void UpdateThumbVFPPredicate(cs_struct *ud, MCInst *MI)
{
unsigned CC;
CC = ITStatus_getITCC(&ITBlock);
if (ITStatus_instrInITBlock(&ITBlock))
ITStatus_advanceITState(&ITBlock);
CC = ITStatus_getITCC(&(ud->ITBlock));
if (ITStatus_instrInITBlock(&(ud->ITBlock)))
ITStatus_advanceITState(&(ud->ITBlock));

MCOperandInfo *OpInfo = ARMInsts[MCInst_getOpcode(MI)].OpInfo;
unsigned short NumOps = ARMInsts[MCInst_getOpcode(MI)].NumOperands;
Expand All @@ -645,12 +637,12 @@ static void UpdateThumbVFPPredicate(MCInst *MI)
}
}

static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_t code_len,
static DecodeStatus _Thumb_getInstruction(cs_struct *ud, MCInst *MI, unsigned char *code, size_t code_len,
uint16_t *Size, size_t Address)
{
uint8_t bytes[4];

ITBlock.size = 0;
ud->ITBlock.size = 0;

//assert((STI.getFeatureBits() & ARM_ModeThumb) &&
// "Asked to disassemble in Thumb mode but Subtarget is in ARM mode!");
Expand All @@ -665,16 +657,16 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_
DecodeStatus result = decodeInstruction_2(DecoderTableThumb16, MI, insn16, Address, 2);
if (result != MCDisassembler_Fail) {
*Size = 2;
Check(&result, AddThumbPredicate(MI));
Check(&result, AddThumbPredicate(ud, MI));
return result;
}

MCInst_clear(MI);
result = decodeInstruction_2(DecoderTableThumbSBit16, MI, insn16, Address, 2);
if (result) {
*Size = 2;
bool InITBlock = ITStatus_instrInITBlock(&ITBlock);
Check(&result, AddThumbPredicate(MI));
bool InITBlock = ITStatus_instrInITBlock(&(ud->ITBlock));
Check(&result, AddThumbPredicate(ud, MI));
AddThumb1SBit(MI, InITBlock);
return result;
}
Expand All @@ -686,10 +678,10 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_

// Nested IT blocks are UNPREDICTABLE. Must be checked before we add
// the Thumb predicate.
if (MCInst_getOpcode(MI) == ARM_t2IT && ITStatus_instrInITBlock(&ITBlock))
if (MCInst_getOpcode(MI) == ARM_t2IT && ITStatus_instrInITBlock(&(ud->ITBlock)))
result = MCDisassembler_SoftFail;

Check(&result, AddThumbPredicate(MI));
Check(&result, AddThumbPredicate(ud, MI));

// If we find an IT instruction, we need to parse its condition
// code and mask operands so that we can apply them correctly
Expand All @@ -698,7 +690,7 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_

unsigned Firstcond = MCOperand_getImm(MCInst_getOperand(MI, 0));
unsigned Mask = MCOperand_getImm(MCInst_getOperand(MI, 1));
ITStatus_setITState(&ITBlock, Firstcond, Mask);
ITStatus_setITState(&(ud->ITBlock), Firstcond, Mask);
}

return result;
Expand All @@ -720,8 +712,8 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_
result = decodeInstruction_4(DecoderTableThumb32, MI, insn32, Address, 2);
if (result != MCDisassembler_Fail) {
*Size = 4;
bool InITBlock = ITStatus_instrInITBlock(&ITBlock);
Check(&result, AddThumbPredicate(MI));
bool InITBlock = ITStatus_instrInITBlock(&(ud->ITBlock));
Check(&result, AddThumbPredicate(ud, MI));
AddThumb1SBit(MI, InITBlock);
return result;
}
Expand All @@ -730,15 +722,15 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_
result = decodeInstruction_4(DecoderTableThumb232, MI, insn32, Address, 2);
if (result != MCDisassembler_Fail) {
*Size = 4;
Check(&result, AddThumbPredicate(MI));
Check(&result, AddThumbPredicate(ud, MI));
return result;
}

MCInst_clear(MI);
result = decodeInstruction_4(DecoderTableVFP32, MI, insn32, Address, 2);
if (result != MCDisassembler_Fail) {
*Size = 4;
UpdateThumbVFPPredicate(MI);
UpdateThumbVFPPredicate(ud, MI);
return result;
}

Expand All @@ -747,7 +739,7 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_
result = decodeInstruction_4(DecoderTableVFP32, MI, insn32, Address, 2);
if (result != MCDisassembler_Fail) {
*Size = 4;
UpdateThumbVFPPredicate(MI);
UpdateThumbVFPPredicate(ud, MI);
return result;
}
}
Expand All @@ -764,7 +756,7 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_
result = decodeInstruction_4(DecoderTableNEONDup32, MI, insn32, Address, 2);
if (result != MCDisassembler_Fail) {
*Size = 4;
Check(&result, AddThumbPredicate(MI));
Check(&result, AddThumbPredicate(ud, MI));
return result;
}
}
Expand All @@ -777,7 +769,7 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_
result = decodeInstruction_4(DecoderTableNEONLoadStore32, MI, NEONLdStInsn, Address, 2);
if (result != MCDisassembler_Fail) {
*Size = 4;
Check(&result, AddThumbPredicate(MI));
Check(&result, AddThumbPredicate(ud, MI));
return result;
}
}
Expand All @@ -791,7 +783,7 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_
result = decodeInstruction_4(DecoderTableNEONData32, MI, NEONDataInsn, Address, 2);
if (result != MCDisassembler_Fail) {
*Size = 4;
Check(&result, AddThumbPredicate(MI));
Check(&result, AddThumbPredicate(ud, MI));
return result;
}
}
Expand Down Expand Up @@ -825,7 +817,7 @@ static DecodeStatus _Thumb_getInstruction(MCInst *MI, unsigned char *code, size_
bool Thumb_getInstruction(csh ud, unsigned char *code, size_t code_len, MCInst *instr,
uint16_t *size, size_t address, void *info)
{
DecodeStatus status = _Thumb_getInstruction(instr, code, code_len, size, address);
DecodeStatus status = _Thumb_getInstruction((cs_struct *)ud, instr, code, code_len, size, address);

//return status == MCDisassembler_Success;
return status != MCDisassembler_Fail;
Expand All @@ -834,7 +826,7 @@ bool Thumb_getInstruction(csh ud, unsigned char *code, size_t code_len, MCInst *
bool ARM_getInstruction(csh ud, unsigned char *code, size_t code_len, MCInst *instr,
uint16_t *size, size_t address, void *info)
{
DecodeStatus status = _ARM_getInstruction(instr, code, code_len, size, address);
DecodeStatus status = _ARM_getInstruction((cs_struct *)ud, instr, code, code_len, size, address);

//return status == MCDisassembler_Success;
return status != MCDisassembler_Fail;
Expand Down
7 changes: 7 additions & 0 deletions cs_priv.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -21,6 +21,12 @@ typedef char *(*GetName_t)(unsigned int reg);

typedef void (*GetID_t)(cs_insn *insn, unsigned int id);

// for ARM only
typedef struct ARM_ITStatus {
unsigned char ITStates[128]; // FIXME
unsigned int size;
} ARM_ITStatus;

typedef struct cs_struct {
cs_arch arch;
cs_mode mode;
Expand All @@ -35,6 +41,7 @@ typedef struct cs_struct {
PostPrinter_t post_printer;
bool micro_mips; // for Mips only
cs_err errnum;
ARM_ITStatus ITBlock; // for Arm only
} cs_struct;

#endif
2 changes: 1 addition & 1 deletion tests/test_arm.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -152,8 +152,8 @@ static void test()
//#define THUMB_CODE "\x00\x47" // bx r0
//#define THUMB_CODE "\x01\x47" // bx r0
//#define THUMB_CODE "\x02\x47" // bx r0
#define THUMB_CODE "\x70\x47\xeb\x46\x83\xb0\xc9\x68\x1f\xb1"
//#define THUMB_CODE "\x0a\xbf" // itet eq
#define THUMB_CODE "\x70\x47\xeb\x46\x83\xb0\xc9\x68\x1f\xb1"
#define THUMB_CODE2 "\x4f\xf0\x00\x01\xbd\xe8\x00\x88\xd1\xe8\x00\xf0"

struct platform platforms[] = {
Expand Down

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