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Fix calculation on lift_rcr and lift_rcl #24

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Merged
merged 3 commits into from
Jul 23, 2024
Merged

Fix calculation on lift_rcr and lift_rcl #24

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3e422f1
Refactor rcl and rcr implementations
Pigrecos Jul 14, 2024
5bf51c7
Update Semantics.cpp
Pigrecos Jul 23, 2024
b064dbd
restore lift_not
NaC-L Jul 23, 2024
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357 changes: 179 additions & 178 deletions lifter/Semantics.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1374,186 +1374,171 @@ namespace arithmeticsAndLogical {
FI;
*/

void lift_rcl(IRBuilder<>& builder,
ZydisDisassembledInstruction& instruction) {
LLVMContext& context = builder.getContext();
auto dest = instruction.operands[0];
auto count = instruction.operands[1];

auto Lvalue = GetOperandValue(builder, dest, dest.size);
auto countValue = GetOperandValue(builder, count, dest.size);
auto carryFlag = getFlag(builder, FLAG_CF);

unsigned long bitWidth = Lvalue->getType()->getIntegerBitWidth();
unsigned maskC = bitWidth == 64 ? 0x3f : 0x1f;

auto actualCount = createAndFolder(
builder, countValue, ConstantInt::get(countValue->getType(), maskC),
"actualCount");

auto wideType = Type::getIntNTy(context, dest.size * 2);
auto wideLvalue = createZExtFolder(builder, Lvalue, wideType);
auto cf_extended = createZExtFolder(builder, carryFlag, wideType);
auto shiftedInCF =
createShlFolder(builder, cf_extended, dest.size, "shiftedincf");
wideLvalue = createOrFolder(builder, wideLvalue,
createZExtFolder(builder, shiftedInCF, wideType,
"shiftedInCFExtended"));

auto leftShifted = createShlFolder(
builder, wideLvalue,
createZExtFolder(builder, actualCount, wideType, "actualCountExtended"),
"leftshifted");
auto rightShiftAmount = createSubFolder(
builder, ConstantInt::get(actualCount->getType(), dest.size),
actualCount, "rightshiftamount");
auto rightShifted = createLShrFolder(
builder, wideLvalue,
createZExtFolder(builder, rightShiftAmount, wideType), "rightshifted");
auto rotated =
createOrFolder(builder, leftShifted,
createZExtFolder(builder, rightShifted, wideType,
"rightShiftedExtended"));

auto result = createZExtOrTruncFolder(builder, rotated, Lvalue->getType());

auto newCFBitPosition = ConstantInt::get(rotated->getType(), dest.size - 1);
auto newCF = createZExtOrTruncFolder(
builder, createLShrFolder(builder, rotated, newCFBitPosition),
Type::getInt1Ty(context), "rclnewcf");

auto msbAfterRotate = createZExtOrTruncFolder(
builder, createLShrFolder(builder, result, dest.size - 1),
Type::getInt1Ty(context), "rclmsbafterrotate");
auto isCountOne =
createICMPFolder(builder, CmpInst::ICMP_EQ, actualCount,
ConstantInt::get(actualCount->getType(), 1));
auto newOF = createZExtOrTruncFolder(
builder, createXorFolder(builder, newCF, msbAfterRotate),
Type::getInt1Ty(context));
newOF = createSelectFolder(builder, isCountOne, newOF,
getFlag(builder, FLAG_OF));

printvalue(Lvalue) printvalue(countValue) printvalue(carryFlag)
printvalue(cf_extended) printvalue(shiftedInCF) printvalue(actualCount)
printvalue(wideLvalue) printvalue(leftShifted)
printvalue(rightShifted) printvalue(rotated) printvalue(result)

SetOperandValue(builder, dest, result);
setFlag(builder, FLAG_CF, newCF);
setFlag(builder, FLAG_OF, newOF);
}

/*
(* RCL and RCR Instructions *)
SIZE := OperandSize;
CASE (determine count) OF
SIZE := 8: tempCOUNT := (COUNT AND 1FH) MOD 9;
SIZE := 16: tempCOUNT := (COUNT AND 1FH) MOD 17;
SIZE := 32: tempCOUNT := COUNT AND 1FH;
SIZE := 64: tempCOUNT := COUNT AND 3FH;
ESAC;
IF OperandSize = 64
THEN COUNTMASK = 3FH;
ELSE COUNTMASK = 1FH;
FI;
(* RCR Instruction Operation *)
IF (COUNT & COUNTMASK) = 1
THEN OF := MSB(DEST) XOR CF;
ELSE OF is undefined;
FI;
WHILE (tempCOUNT ≠ 0)
DO
tempCF := LSB(SRC);
DEST := (DEST / 2) + (CF * 2SIZE);
CF := tempCF;
tempCOUNT := tempCOUNT – 1;
OD;
ELIHW;

*/
void lift_rcr(IRBuilder<>& builder,
ZydisDisassembledInstruction& instruction) {
LLVMContext& context = builder.getContext();
auto dest = instruction.operands[0];
auto count = instruction.operands[1];

auto Lvalue = GetOperandValue(builder, dest, dest.size);
auto countValue = GetOperandValue(builder, count, dest.size);
auto carryFlag = getFlag(builder, FLAG_CF);

unsigned long bitWidth = Lvalue->getType()->getIntegerBitWidth();
unsigned maskC = bitWidth == 64 ? 0x3f : 0x1f;

auto actualCount = createAndFolder(
builder, countValue, ConstantInt::get(countValue->getType(), maskC),
"actualCount");
auto wideType = Type::getIntNTy(context, dest.size * 2);
auto wideLvalue = createZExtFolder(builder, Lvalue, wideType);
auto shiftedInCF = createShlFolder(
builder, createZExtFolder(builder, carryFlag, wideType), dest.size);
wideLvalue = createOrFolder(builder, wideLvalue,
createZExtFolder(builder, shiftedInCF, wideType,
"shiftedInCFExtended"));

auto rightShifted = createLShrFolder(
builder, wideLvalue,
createZExtFolder(builder, actualCount, wideType, "actualCountExtended"),
"rightshifted");
auto leftShiftAmount = createSubFolder(
builder, ConstantInt::get(actualCount->getType(), dest.size),
actualCount);
auto leftShifted =
createShlFolder(builder, wideLvalue,
createZExtFolder(builder, leftShiftAmount, wideType,
"leftShiftAmountExtended"));
auto rotated = createOrFolder(builder, rightShifted, leftShifted);

auto result = createZExtOrTruncFolder(builder, rotated, Lvalue->getType());

auto newCFBitPosition = ConstantInt::get(rotated->getType(), dest.size - 1);
auto newCF = createZExtOrTruncFolder(
builder, createLShrFolder(builder, rotated, newCFBitPosition),
Type::getInt1Ty(context), "rcrcf");

auto msbAfterRotate = createZExtOrTruncFolder(
builder, createLShrFolder(builder, result, dest.size - 1),
Type::getInt1Ty(context), "rcrmsb");
auto newOF = createSelectFolder(
builder,
createICMPFolder(builder, CmpInst::ICMP_EQ, actualCount,
ConstantInt::get(actualCount->getType(), 1)),
createXorFolder(builder, newCF, msbAfterRotate),
getFlag(builder, FLAG_OF));

Value* isCountOne =
createICMPFolder(builder, CmpInst::ICMP_EQ, actualCount,
ConstantInt::get(actualCount->getType(), 1));

newCF = createSelectFolder(builder, isCountOne, newOF,
getFlag(builder, FLAG_OF));
result = createSelectFolder(builder, isCountOne, result, Lvalue);

SetOperandValue(builder, dest, result);
setFlag(builder, FLAG_CF, newCF);
setFlag(builder, FLAG_OF, newOF);
}

void lift_not(IRBuilder<>& builder,
ZydisDisassembledInstruction& instruction) {

auto dest = instruction.operands[0];
void lift_rcl(IRBuilder<>& builder, ZydisDisassembledInstruction& instruction) {
LLVMContext& context = builder.getContext();
auto dest = instruction.operands[0];
auto count = instruction.operands[1];

Value* Lvalue = GetOperandValue(builder, dest, dest.size);
Value* countValue = GetOperandValue(builder, count, dest.size);
Value* carryFlag = getFlag(builder, FLAG_CF);

unsigned long bitWidth = Lvalue->getType()->getIntegerBitWidth();
unsigned maskC = bitWidth == 64 ? 0x3f : 0x1f;

// Calculate actual count
Value* countMask = ConstantInt::get(countValue->getType(), maskC);
Value* actualCount = createAndFolder(builder, countValue, countMask, "actualCount");

// Extend Lvalue to double width
Type* wideType = Type::getIntNTy(context, dest.size * 2);
Value* wideLvalue = createZExtFolder(builder, Lvalue, wideType);

// Shift the carry flag into the LSB
Value* cf_extended = createZExtFolder(builder, carryFlag, wideType);
Value* shiftedInCF = createOrFolder(builder, wideLvalue, cf_extended, "shiftedincf");

// Perform the rotation
Value* shiftAmount = createZExtFolder(builder, actualCount, wideType);
Value* bitWidthPlusOne = ConstantInt::get(wideType, bitWidth + 1);
Value* inverseShiftAmount = createSubFolder(builder, bitWidthPlusOne, shiftAmount);

Value* leftShifted = createShlFolder(builder, shiftedInCF, shiftAmount, "leftshifted");
Value* rightShifted = createLShrFolder(builder, shiftedInCF, inverseShiftAmount, "rightshifted");
Value* rotated = createOrFolder(builder, leftShifted, rightShifted);

// Extract the result and new carry flag
Value* result = createTruncFolder(builder, rotated, Lvalue->getType());
Value* newCFShifted = createLShrFolder(builder, rotated, ConstantInt::get(wideType, bitWidth));
Value* newCF = createTruncFolder(builder, newCFShifted, Type::getInt1Ty(context), "rclnewcf");

// Calculate OF (only valid when count == 1)
Value* resultMSB = createLShrFolder(builder, result, ConstantInt::get(result->getType(), bitWidth - 1));
Value* msbAfterRotate = createTruncFolder(builder, resultMSB, Type::getInt1Ty(context), "rclmsbafterrotate");

Value* one = ConstantInt::get(actualCount->getType(), 1);
Value* isCountOne = createICMPFolder(builder, CmpInst::ICMP_EQ, actualCount, one);

Value* newOF = createXorFolder(builder, newCF, msbAfterRotate);
Value* currentOF = getFlag(builder, FLAG_OF);
newOF = createSelectFolder(builder, isCountOne, newOF, currentOF);

// Set the result and flags
SetOperandValue(builder, dest, result);
setFlag(builder, FLAG_CF, newCF);
setFlag(builder, FLAG_OF, newOF);

// Debug output
printvalue(Lvalue);
printvalue(countValue);
printvalue(carryFlag);
printvalue(actualCount);
printvalue(shiftedInCF);
printvalue(rotated);
printvalue(result);
printvalue(newCF);
printvalue(newOF);
}

auto Rvalue = GetOperandValue(builder, dest, dest.size);
Rvalue = builder.CreateNot(
Rvalue, "realnot-" + to_string(instruction.runtime_address) + "-");
SetOperandValue(builder, dest, Rvalue,
to_string(instruction.runtime_address));
/*
(* RCL and RCR Instructions *)
SIZE := OperandSize;
CASE (determine count) OF
SIZE := 8: tempCOUNT := (COUNT AND 1FH) MOD 9;
SIZE := 16: tempCOUNT := (COUNT AND 1FH) MOD 17;
SIZE := 32: tempCOUNT := COUNT AND 1FH;
SIZE := 64: tempCOUNT := COUNT AND 3FH;
ESAC;
IF OperandSize = 64
THEN COUNTMASK = 3FH;
ELSE COUNTMASK = 1FH;
FI;
(* RCR Instruction Operation *)
IF (COUNT & COUNTMASK) = 1
THEN OF := MSB(DEST) XOR CF;
ELSE OF is undefined;
FI;
WHILE (tempCOUNT ≠ 0)
DO
tempCF := LSB(SRC);
DEST := (DEST / 2) + (CF * 2SIZE);
CF := tempCF;
tempCOUNT := tempCOUNT – 1;
OD;
ELIHW;

printvalue(Rvalue);
// Flags Affected
// None
}
*/
void lift_rcr(IRBuilder<>& builder, ZydisDisassembledInstruction& instruction) {
LLVMContext& context = builder.getContext();
auto dest = instruction.operands[0];
auto count = instruction.operands[1];

Value* Lvalue = GetOperandValue(builder, dest, dest.size);
Value* countValue = GetOperandValue(builder, count, dest.size);
Value* carryFlag = getFlag(builder, FLAG_CF);

unsigned long bitWidth = Lvalue->getType()->getIntegerBitWidth();
unsigned maskC = bitWidth == 64 ? 0x3f : 0x1f;

// Calculate actual count
Value* countMask = ConstantInt::get(countValue->getType(), maskC);
Value* actualCount = createAndFolder(builder, countValue, countMask, "actualCount");

// Extend Lvalue to double width and shift left by 1 to make room for CF
Type* wideType = Type::getIntNTy(context, dest.size * 2);
Value* wideLvalue = createZExtFolder(builder, Lvalue, wideType);
Value* shiftedLvalue =
createShlFolder(builder, wideLvalue, ConstantInt::get(wideType, 1));

// Insert the carry flag into the MSB
Value* cf_extended = createZExtFolder(builder, carryFlag, wideType);
Value* shiftedCF = createShlFolder(builder, cf_extended, ConstantInt::get(wideType, bitWidth));
Value* shiftedInCF = createOrFolder(builder, shiftedLvalue, shiftedCF, "shiftedincf");

// Perform the rotation
Value* shiftAmount = createZExtFolder(builder, actualCount, wideType);
Value* bitWidthPlusOne = ConstantInt::get(wideType, bitWidth + 1);
Value* inverseShiftAmount = createSubFolder(builder, bitWidthPlusOne, shiftAmount);

Value* rightShifted = createLShrFolder(builder, shiftedInCF, shiftAmount, "rightshifted");
Value* leftShifted = createShlFolder(builder, shiftedInCF, inverseShiftAmount, "leftshifted");
Value* rotated = createOrFolder(builder, rightShifted, leftShifted);

// Extract the result and new carry flag
Value* shiftedResult = createLShrFolder(builder, rotated, ConstantInt::get(wideType, 1));
Value* result = createTruncFolder(builder, shiftedResult, Lvalue->getType());
Value* newCF = createTruncFolder(builder, rotated, Type::getInt1Ty(context), "rcrnewcf");

// Calculate OF (only valid when count == 1)
Value* resultMSB = createLShrFolder(builder, result, ConstantInt::get(result->getType(), bitWidth - 1));
Value* msbAfterRotate = createTruncFolder(builder, resultMSB, Type::getInt1Ty(context), "rcrmsbafterrotate");

Value* LvalueMSB = createLShrFolder(builder, Lvalue, ConstantInt::get(Lvalue->getType(), bitWidth - 1));
Value* msbBeforeRotate = createTruncFolder(builder, LvalueMSB, Type::getInt1Ty(context), "rcrmsbbeforerotate");

Value* one = ConstantInt::get(actualCount->getType(), 1);
Value* isCountOne = createICMPFolder(builder, CmpInst::ICMP_EQ, actualCount, one);

Value* newOF = createXorFolder(builder, msbBeforeRotate, msbAfterRotate);
Value* currentOF = getFlag(builder, FLAG_OF);
newOF = createSelectFolder(builder, isCountOne, newOF, currentOF);

// Set the result and flags
SetOperandValue(builder, dest, result);
setFlag(builder, FLAG_CF, newCF);
setFlag(builder, FLAG_OF, newOF);

// Debug output
printvalue(Lvalue);
printvalue(countValue);
printvalue(carryFlag);
printvalue(actualCount);
printvalue(shiftedInCF);
printvalue(rotated);
printvalue(result);
printvalue(newCF);
printvalue(newOF);
}

void lift_neg(IRBuilder<>& builder,
ZydisDisassembledInstruction& instruction) {
Expand Down Expand Up @@ -1978,6 +1963,22 @@ namespace arithmeticsAndLogical {
setFlag(builder, FLAG_SF, sf);
setFlag(builder, FLAG_ZF, zf);
}

void lift_not(IRBuilder<>& builder,
ZydisDisassembledInstruction& instruction) {

auto dest = instruction.operands[0];

auto Rvalue = GetOperandValue(builder, dest, dest.size);
Rvalue = builder.CreateNot(
Rvalue, "realnot-" + to_string(instruction.runtime_address) + "-");
SetOperandValue(builder, dest, Rvalue,
to_string(instruction.runtime_address));

printvalue(Rvalue);
// Flags Affected
// None
}

void lift_xchg(IRBuilder<>& builder,
ZydisDisassembledInstruction& instruction) {
Expand Down