fix comparison of floating point numbers (e4c445a6) · Commits · Adéla Štěpková / reverser

include/core/instructionBuilder.hpp

+27 −3

Original line number	Diff line number	Diff line
		@@ -350,13 +350,29 @@ public:
		return newI;
		}

		/// @brief Create ICmp EQ or FCmp OEQ based on the value's type
		/// @brief Create ICmp EQ or FCmp UEQ based on the value's type
		Value* CreateCmpEQ(Value* LHS, Value* RHS, const Twine& Name = "", Value* registerTo = nullptr)
		{
		if (LHS->getType()->isIntOrIntVectorTy()) {
		return CreateICmpEQ(LHS, RHS, Name, registerTo);
		}
		return CreateFCmpOEQ(LHS, RHS, Name, nullptr, registerTo);
		else if (LHS->getType()->isFPOrFPVectorTy()) {
		return equalFloats(LHS, RHS, Name, registerTo);
		}
		assert(false && "cannot compare type that is not integer of floating point");
		}

		/// @brief Compare two floats for equality -- return an instruction that is true if either both
		/// are ordered and equal, or both are NaN. Used for comparisons of nondeterministic values
		/// generated during reversing.
		Value* equalFloats(Value* LHS, Value* RHS, const Twine& Name = "", Value* registerTo = nullptr)
		{
		auto* orderedEq = CreateFCmpOEQ(LHS, RHS);
		auto* isLHSNan = CreateFCmp(CmpInst::Predicate::FCMP_UNO, LHS, LHS);
		auto* isRHSNan = CreateFCmp(CmpInst::Predicate::FCMP_UNO, RHS, RHS);
		auto* bothNan = CreateAnd(isLHSNan, isRHSNan);
		auto* oequalOrBothNan = CreateOr(orderedEq, bothNan, Name, registerTo);
		return oequalOrBothNan;
		}

		Value* CreateICmpEQ(Value* LHS, Value* RHS, const Twine& Name = "", Value* registerTo = nullptr)
		@@ -374,6 +390,14 @@ public:
		return newI;
		}

		Value* CreateFCmpUEQ(Value* LHS, Value* RHS, const Twine& Name = "",
		MDNode* FPMathTag = nullptr, Value* registerTo = nullptr)
		{
		auto* newI = _builder.CreateFCmpUEQ(LHS, RHS, Name, FPMathTag);
		registerValue(registerTo, newI);
		return newI;
		}

		Value* CreateICmp(CmpInst::Predicate P, Value* LHS, Value* RHS, const Twine& Name = "",
		Value* registerTo = nullptr)
		{
		@@ -487,7 +511,7 @@ public:
		Value* CreateFDiv(Value* L, Value* R, const Twine& Name = "", MDNode* FPMD = nullptr,
		Value* registerTo = nullptr)
		{
		auto* newI = _builder.CreateFMul(L, R, Name, FPMD);
		auto* newI = _builder.CreateFDiv(L, R, Name, FPMD);
		registerValue(registerTo, newI);
		return newI;
		}