//===- ValueTrackingTest.cpp - ValueTracking tests ------------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// #include "llvm/Analysis/ValueTracking.h" #include "llvm/Analysis/AssumptionCache.h" #include "llvm/AsmParser/Parser.h" #include "llvm/IR/ConstantRange.h" #include "llvm/IR/Dominators.h" #include "llvm/IR/Function.h" #include "llvm/IR/InstIterator.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/LLVMContext.h" #include "llvm/IR/Module.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/KnownBits.h" #include "llvm/Support/SourceMgr.h" #include "llvm/Transforms/Utils/Local.h" #include "gtest/gtest.h" using namespace llvm; namespace { static Instruction *findInstructionByNameOrNull(Function *F, StringRef Name) { for (Instruction &I : instructions(F)) if (I.getName() == Name) return &I; return nullptr; } static Instruction &findInstructionByName(Function *F, StringRef Name) { auto *I = findInstructionByNameOrNull(F, Name); if (I) return *I; llvm_unreachable("Expected value not found"); } class ValueTrackingTest : public testing::Test { protected: std::unique_ptr parseModule(StringRef Assembly) { SMDiagnostic Error; std::unique_ptr M = parseAssemblyString(Assembly, Error, Context); std::string errMsg; raw_string_ostream os(errMsg); Error.print("", os); EXPECT_TRUE(M) << os.str(); return M; } void parseAssembly(StringRef Assembly) { M = parseModule(Assembly); ASSERT_TRUE(M); F = M->getFunction("test"); ASSERT_TRUE(F) << "Test must have a function @test"; if (!F) return; A = findInstructionByNameOrNull(F, "A"); ASSERT_TRUE(A) << "@test must have an instruction %A"; CxtI = findInstructionByNameOrNull(F, "CxtI"); CxtI2 = findInstructionByNameOrNull(F, "CxtI2"); CxtI3 = findInstructionByNameOrNull(F, "CxtI3"); } LLVMContext Context; std::unique_ptr M; Function *F = nullptr; Instruction *A = nullptr; // Context instructions (optional) Instruction *CxtI = nullptr, *CxtI2 = nullptr, *CxtI3 = nullptr; }; class MatchSelectPatternTest : public ValueTrackingTest { protected: void expectPattern(const SelectPatternResult &P) { Value *LHS, *RHS; Instruction::CastOps CastOp; SelectPatternResult R = matchSelectPattern(A, LHS, RHS, &CastOp); EXPECT_EQ(P.Flavor, R.Flavor); EXPECT_EQ(P.NaNBehavior, R.NaNBehavior); EXPECT_EQ(P.Ordered, R.Ordered); } }; class ComputeKnownBitsTest : public ValueTrackingTest { protected: void expectKnownBits(uint64_t Zero, uint64_t One) { auto Known = computeKnownBits(A, M->getDataLayout()); ASSERT_FALSE(Known.hasConflict()); EXPECT_EQ(Known.One.getZExtValue(), One); EXPECT_EQ(Known.Zero.getZExtValue(), Zero); } }; } TEST_F(MatchSelectPatternTest, SimpleFMin) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ult float %a, 5.0\n" " %A = select i1 %1, float %a, float 5.0\n" " ret float %A\n" "}\n"); expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false}); } TEST_F(MatchSelectPatternTest, SimpleFMax) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float %a, 5.0\n" " %A = select i1 %1, float %a, float 5.0\n" " ret float %A\n" "}\n"); expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true}); } TEST_F(MatchSelectPatternTest, SwappedFMax) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float 5.0, %a\n" " %A = select i1 %1, float %a, float 5.0\n" " ret float %A\n" "}\n"); expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, false}); } TEST_F(MatchSelectPatternTest, SwappedFMax2) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float %a, 5.0\n" " %A = select i1 %1, float 5.0, float %a\n" " ret float %A\n" "}\n"); expectPattern({SPF_FMAXNUM, SPNB_RETURNS_NAN, false}); } TEST_F(MatchSelectPatternTest, SwappedFMax3) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ult float %a, 5.0\n" " %A = select i1 %1, float 5.0, float %a\n" " ret float %A\n" "}\n"); expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true}); } TEST_F(MatchSelectPatternTest, FastFMin) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp nnan olt float %a, 5.0\n" " %A = select i1 %1, float %a, float 5.0\n" " ret float %A\n" "}\n"); expectPattern({SPF_FMINNUM, SPNB_RETURNS_ANY, false}); } TEST_F(MatchSelectPatternTest, FMinConstantZero) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ole float %a, 0.0\n" " %A = select i1 %1, float %a, float 0.0\n" " ret float %A\n" "}\n"); // This shouldn't be matched, as %a could be -0.0. expectPattern({SPF_UNKNOWN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, FMinConstantZeroNsz) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp nsz ole float %a, 0.0\n" " %A = select i1 %1, float %a, float 0.0\n" " ret float %A\n" "}\n"); // But this should be, because we've ignored signed zeroes. expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero1) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float -0.0, %a\n" " %A = select i1 %1, float 0.0, float %a\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, true}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero2) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float %a, -0.0\n" " %A = select i1 %1, float 0.0, float %a\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero3) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float 0.0, %a\n" " %A = select i1 %1, float -0.0, float %a\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, true}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero4) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float %a, 0.0\n" " %A = select i1 %1, float -0.0, float %a\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero5) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float -0.0, %a\n" " %A = select i1 %1, float %a, float 0.0\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, false}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero6) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float %a, -0.0\n" " %A = select i1 %1, float %a, float 0.0\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero7) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float 0.0, %a\n" " %A = select i1 %1, float %a, float -0.0\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, false}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZero8) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float %a, 0.0\n" " %A = select i1 %1, float %a, float -0.0\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero1) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float -0.0, %a\n" " %A = select i1 %1, float 0.0, float %a\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMAXNUM, SPNB_RETURNS_NAN, true}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero2) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float %a, -0.0\n" " %A = select i1 %1, float 0.0, float %a\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMAXNUM, SPNB_RETURNS_NAN, false}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero3) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float 0.0, %a\n" " %A = select i1 %1, float -0.0, float %a\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMAXNUM, SPNB_RETURNS_NAN, true}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero4) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float %a, 0.0\n" " %A = select i1 %1, float -0.0, float %a\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMAXNUM, SPNB_RETURNS_NAN, false}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero5) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float -0.0, %a\n" " %A = select i1 %1, float %a, float 0.0\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, false}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero6) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float %a, -0.0\n" " %A = select i1 %1, float %a, float 0.0\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero7) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp olt float 0.0, %a\n" " %A = select i1 %1, float %a, float -0.0\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, false}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZero8) { parseAssembly( "define float @test(float %a) {\n" " %1 = fcmp ogt float %a, 0.0\n" " %A = select i1 %1, float %a, float -0.0\n" " ret float %A\n" "}\n"); // The sign of zero doesn't matter in fcmp. expectPattern({SPF_FMAXNUM, SPNB_RETURNS_OTHER, true}); } TEST_F(MatchSelectPatternTest, FMinMismatchConstantZeroVecUndef) { parseAssembly( "define <2 x float> @test(<2 x float> %a) {\n" " %1 = fcmp ogt <2 x float> %a, \n" " %A = select <2 x i1> %1, <2 x float> , <2 x float> %a\n" " ret <2 x float> %A\n" "}\n"); // An undef in a vector constant can not be back-propagated for this analysis. expectPattern({SPF_UNKNOWN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, FMaxMismatchConstantZeroVecUndef) { parseAssembly( "define <2 x float> @test(<2 x float> %a) {\n" " %1 = fcmp ogt <2 x float> %a, zeroinitializer\n" " %A = select <2 x i1> %1, <2 x float> %a, <2 x float> \n" " ret <2 x float> %A\n" "}\n"); // An undef in a vector constant can not be back-propagated for this analysis. expectPattern({SPF_UNKNOWN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, VectorFMinimum) { parseAssembly( "define <4 x float> @test(<4 x float> %a) {\n" " %1 = fcmp ule <4 x float> %a, \n" " \n" " %A = select <4 x i1> %1, <4 x float> %a,\n" " <4 x float> \n" " ret <4 x float> %A\n" "}\n"); // Check that pattern matching works on vectors where each lane has the same // unordered pattern. expectPattern({SPF_FMINNUM, SPNB_RETURNS_NAN, false}); } TEST_F(MatchSelectPatternTest, VectorFMinOtherOrdered) { parseAssembly( "define <4 x float> @test(<4 x float> %a) {\n" " %1 = fcmp ole <4 x float> %a, \n" " \n" " %A = select <4 x i1> %1, <4 x float> %a,\n" " <4 x float> \n" " ret <4 x float> %A\n" "}\n"); // Check that pattern matching works on vectors where each lane has the same // ordered pattern. expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true}); } TEST_F(MatchSelectPatternTest, VectorNotFMinimum) { parseAssembly( "define <4 x float> @test(<4 x float> %a) {\n" " %1 = fcmp ule <4 x float> %a, \n" " \n" " %A = select <4 x i1> %1, <4 x float> %a,\n" " <4 x float> \n" " ret <4 x float> %A\n" "}\n"); // The lane that contains a NaN (0x7ff80...) behaves like a // non-NaN-propagating min and the other lines behave like a NaN-propagating // min, so check that neither is returned. expectPattern({SPF_UNKNOWN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, VectorNotFMinZero) { parseAssembly( "define <4 x float> @test(<4 x float> %a) {\n" " %1 = fcmp ule <4 x float> %a, \n" " \n" " %A = select <4 x i1> %1, <4 x float> %a,\n" " <4 x float> \n" " ret <4 x float> %A\n" "}\n"); // Always selects the second lane of %a if it is positive or negative zero, so // this is stricter than a min. expectPattern({SPF_UNKNOWN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, DoubleCastU) { parseAssembly( "define i32 @test(i8 %a, i8 %b) {\n" " %1 = icmp ult i8 %a, %b\n" " %2 = zext i8 %a to i32\n" " %3 = zext i8 %b to i32\n" " %A = select i1 %1, i32 %2, i32 %3\n" " ret i32 %A\n" "}\n"); // We should be able to look through the situation where we cast both operands // to the select. expectPattern({SPF_UMIN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, DoubleCastS) { parseAssembly( "define i32 @test(i8 %a, i8 %b) {\n" " %1 = icmp slt i8 %a, %b\n" " %2 = sext i8 %a to i32\n" " %3 = sext i8 %b to i32\n" " %A = select i1 %1, i32 %2, i32 %3\n" " ret i32 %A\n" "}\n"); // We should be able to look through the situation where we cast both operands // to the select. expectPattern({SPF_SMIN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, DoubleCastBad) { parseAssembly( "define i32 @test(i8 %a, i8 %b) {\n" " %1 = icmp ult i8 %a, %b\n" " %2 = zext i8 %a to i32\n" " %3 = sext i8 %b to i32\n" " %A = select i1 %1, i32 %2, i32 %3\n" " ret i32 %A\n" "}\n"); // The cast types here aren't the same, so we cannot match an UMIN. expectPattern({SPF_UNKNOWN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotSMin) { parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %cmp = icmp sgt i8 %a, %b\n" " %an = xor i8 %a, -1\n" " %bn = xor i8 %b, -1\n" " %A = select i1 %cmp, i8 %an, i8 %bn\n" " ret i8 %A\n" "}\n"); expectPattern({SPF_SMIN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotSMinSwap) { parseAssembly( "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n" " %cmp = icmp slt <2 x i8> %a, %b\n" " %an = xor <2 x i8> %a, \n" " %bn = xor <2 x i8> %b, \n" " %A = select <2 x i1> %cmp, <2 x i8> %bn, <2 x i8> %an\n" " ret <2 x i8> %A\n" "}\n"); expectPattern({SPF_SMIN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotSMax) { parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %cmp = icmp slt i8 %a, %b\n" " %an = xor i8 %a, -1\n" " %bn = xor i8 %b, -1\n" " %A = select i1 %cmp, i8 %an, i8 %bn\n" " ret i8 %A\n" "}\n"); expectPattern({SPF_SMAX, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotSMaxSwap) { parseAssembly( "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n" " %cmp = icmp sgt <2 x i8> %a, %b\n" " %an = xor <2 x i8> %a, \n" " %bn = xor <2 x i8> %b, \n" " %A = select <2 x i1> %cmp, <2 x i8> %bn, <2 x i8> %an\n" " ret <2 x i8> %A\n" "}\n"); expectPattern({SPF_SMAX, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotUMin) { parseAssembly( "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n" " %cmp = icmp ugt <2 x i8> %a, %b\n" " %an = xor <2 x i8> %a, \n" " %bn = xor <2 x i8> %b, \n" " %A = select <2 x i1> %cmp, <2 x i8> %an, <2 x i8> %bn\n" " ret <2 x i8> %A\n" "}\n"); expectPattern({SPF_UMIN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotUMinSwap) { parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %cmp = icmp ult i8 %a, %b\n" " %an = xor i8 %a, -1\n" " %bn = xor i8 %b, -1\n" " %A = select i1 %cmp, i8 %bn, i8 %an\n" " ret i8 %A\n" "}\n"); expectPattern({SPF_UMIN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotUMax) { parseAssembly( "define <2 x i8> @test(<2 x i8> %a, <2 x i8> %b) {\n" " %cmp = icmp ult <2 x i8> %a, %b\n" " %an = xor <2 x i8> %a, \n" " %bn = xor <2 x i8> %b, \n" " %A = select <2 x i1> %cmp, <2 x i8> %an, <2 x i8> %bn\n" " ret <2 x i8> %A\n" "}\n"); expectPattern({SPF_UMAX, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotUMaxSwap) { parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %cmp = icmp ugt i8 %a, %b\n" " %an = xor i8 %a, -1\n" " %bn = xor i8 %b, -1\n" " %A = select i1 %cmp, i8 %bn, i8 %an\n" " ret i8 %A\n" "}\n"); expectPattern({SPF_UMAX, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotEq) { parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %cmp = icmp eq i8 %a, %b\n" " %an = xor i8 %a, -1\n" " %bn = xor i8 %b, -1\n" " %A = select i1 %cmp, i8 %bn, i8 %an\n" " ret i8 %A\n" "}\n"); expectPattern({SPF_UNKNOWN, SPNB_NA, false}); } TEST_F(MatchSelectPatternTest, NotNotNe) { parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %cmp = icmp ne i8 %a, %b\n" " %an = xor i8 %a, -1\n" " %bn = xor i8 %b, -1\n" " %A = select i1 %cmp, i8 %bn, i8 %an\n" " ret i8 %A\n" "}\n"); expectPattern({SPF_UNKNOWN, SPNB_NA, false}); } TEST(ValueTracking, GuaranteedToTransferExecutionToSuccessor) { StringRef Assembly = "declare void @nounwind_readonly(i32*) nounwind readonly " "declare void @nounwind_argmemonly(i32*) nounwind argmemonly " "declare void @throws_but_readonly(i32*) readonly " "declare void @throws_but_argmemonly(i32*) argmemonly " "declare void @nounwind_willreturn(i32*) nounwind willreturn" " " "declare void @unknown(i32*) " " " "define void @f(i32* %p) { " " call void @nounwind_readonly(i32* %p) " " call void @nounwind_argmemonly(i32* %p) " " call void @throws_but_readonly(i32* %p) " " call void @throws_but_argmemonly(i32* %p) " " call void @unknown(i32* %p) nounwind readonly " " call void @unknown(i32* %p) nounwind argmemonly " " call void @unknown(i32* %p) readonly " " call void @unknown(i32* %p) argmemonly " " call void @nounwind_willreturn(i32* %p)" " ret void " "} "; LLVMContext Context; SMDiagnostic Error; auto M = parseAssemblyString(Assembly, Error, Context); assert(M && "Bad assembly?"); auto *F = M->getFunction("f"); assert(F && "Bad assembly?"); auto &BB = F->getEntryBlock(); bool ExpectedAnswers[] = { true, // call void @nounwind_readonly(i32* %p) true, // call void @nounwind_argmemonly(i32* %p) false, // call void @throws_but_readonly(i32* %p) false, // call void @throws_but_argmemonly(i32* %p) true, // call void @unknown(i32* %p) nounwind readonly true, // call void @unknown(i32* %p) nounwind argmemonly false, // call void @unknown(i32* %p) readonly false, // call void @unknown(i32* %p) argmemonly true, // call void @nounwind_willreturn(i32* %p) false, // ret void }; int Index = 0; for (auto &I : BB) { EXPECT_EQ(isGuaranteedToTransferExecutionToSuccessor(&I), ExpectedAnswers[Index]) << "Incorrect answer at instruction " << Index << " = " << I; Index++; } } TEST_F(ValueTrackingTest, ComputeNumSignBits_PR32045) { parseAssembly( "define i32 @test(i32 %a) {\n" " %A = ashr i32 %a, -1\n" " ret i32 %A\n" "}\n"); EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u); } // No guarantees for canonical IR in this analysis, so this just bails out. TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle) { parseAssembly( "define <2 x i32> @test() {\n" " %A = shufflevector <2 x i32> undef, <2 x i32> undef, <2 x i32> \n" " ret <2 x i32> %A\n" "}\n"); EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u); } // No guarantees for canonical IR in this analysis, so a shuffle element that // references an undef value means this can't return any extra information. TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle2) { parseAssembly( "define <2 x i32> @test(<2 x i1> %x) {\n" " %sext = sext <2 x i1> %x to <2 x i32>\n" " %A = shufflevector <2 x i32> %sext, <2 x i32> undef, <2 x i32> \n" " ret <2 x i32> %A\n" "}\n"); EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 1u); } TEST_F(ValueTrackingTest, ComputeNumSignBits_Shuffle_Pointers) { parseAssembly( "define <2 x i32*> @test(<2 x i32*> %x) {\n" " %A = shufflevector <2 x i32*> zeroinitializer, <2 x i32*> undef, <2 x i32> zeroinitializer\n" " ret <2 x i32*> %A\n" "}\n"); EXPECT_EQ(ComputeNumSignBits(A, M->getDataLayout()), 64u); } TEST(ValueTracking, propagatesPoison) { std::string AsmHead = "declare i32 @g(i32)\n" "define void @f(i32 %x, i32 %y, float %fx, float %fy, " "i1 %cond, i8* %p) {\n"; std::string AsmTail = " ret void\n}"; // (propagates poison?, IR instruction) SmallVector, 32> Data = { {true, "add i32 %x, %y"}, {true, "add nsw nuw i32 %x, %y"}, {true, "ashr i32 %x, %y"}, {true, "lshr exact i32 %x, 31"}, {true, "fcmp oeq float %fx, %fy"}, {true, "icmp eq i32 %x, %y"}, {true, "getelementptr i8, i8* %p, i32 %x"}, {true, "getelementptr inbounds i8, i8* %p, i32 %x"}, {true, "bitcast float %fx to i32"}, {false, "select i1 %cond, i32 %x, i32 %y"}, {false, "freeze i32 %x"}, {true, "udiv i32 %x, %y"}, {true, "urem i32 %x, %y"}, {true, "sdiv exact i32 %x, %y"}, {true, "srem i32 %x, %y"}, {false, "call i32 @g(i32 %x)"}}; std::string AssemblyStr = AsmHead; for (auto &Itm : Data) AssemblyStr += Itm.second + "\n"; AssemblyStr += AsmTail; LLVMContext Context; SMDiagnostic Error; auto M = parseAssemblyString(AssemblyStr, Error, Context); assert(M && "Bad assembly?"); auto *F = M->getFunction("f"); assert(F && "Bad assembly?"); auto &BB = F->getEntryBlock(); int Index = 0; for (auto &I : BB) { if (isa(&I)) break; EXPECT_EQ(propagatesPoison(cast(&I)), Data[Index].first) << "Incorrect answer at instruction " << Index << " = " << I; Index++; } } TEST_F(ValueTrackingTest, programUndefinedIfPoison) { parseAssembly("declare i32 @any_num()" "define void @test(i32 %mask) {\n" " %A = call i32 @any_num()\n" " %B = or i32 %A, %mask\n" " udiv i32 1, %B" " ret void\n" "}\n"); // If %A was poison, udiv raises UB regardless of %mask's value EXPECT_EQ(programUndefinedIfPoison(A), true); } TEST_F(ValueTrackingTest, programUndefinedIfUndefOrPoison) { parseAssembly("declare i32 @any_num()" "define void @test(i32 %mask) {\n" " %A = call i32 @any_num()\n" " %B = or i32 %A, %mask\n" " udiv i32 1, %B" " ret void\n" "}\n"); // If %A was undef and %mask was 1, udiv does not raise UB EXPECT_EQ(programUndefinedIfUndefOrPoison(A), false); } TEST_F(ValueTrackingTest, isGuaranteedNotToBePoison_exploitBranchCond) { parseAssembly("declare i1 @any_bool()" "define void @test(i1 %y) {\n" " %A = call i1 @any_bool()\n" " %cond = and i1 %A, %y\n" " br i1 %cond, label %BB1, label %BB2\n" "BB1:\n" " ret void\n" "BB2:\n" " ret void\n" "}\n"); DominatorTree DT(*F); for (auto &BB : *F) { if (&BB == &F->getEntryBlock()) continue; EXPECT_EQ(isGuaranteedNotToBePoison(A, nullptr, BB.getTerminator(), &DT), true) << "isGuaranteedNotToBePoison does not hold at " << *BB.getTerminator(); } } TEST_F(ValueTrackingTest, isGuaranteedNotToBePoison_phi) { parseAssembly("declare i32 @any_i32(i32)" "define void @test() {\n" "ENTRY:\n" " br label %LOOP\n" "LOOP:\n" " %A = phi i32 [0, %ENTRY], [%A.next, %NEXT]\n" " %A.next = call i32 @any_i32(i32 %A)\n" " %cond = icmp eq i32 %A.next, 0\n" " br i1 %cond, label %NEXT, label %EXIT\n" "NEXT:\n" " br label %LOOP\n" "EXIT:\n" " ret void\n" "}\n"); DominatorTree DT(*F); for (auto &BB : *F) { if (BB.getName() == "LOOP") { EXPECT_EQ(isGuaranteedNotToBePoison(A, nullptr, A, &DT), true) << "isGuaranteedNotToBePoison does not hold"; } } } TEST_F(ValueTrackingTest, isGuaranteedNotToBeUndefOrPoison) { parseAssembly("declare void @f(i32 noundef)" "define void @test(i32 %x) {\n" " %A = bitcast i32 %x to i32\n" " call void @f(i32 noundef %x)\n" " ret void\n" "}\n"); EXPECT_EQ(isGuaranteedNotToBeUndefOrPoison(A), true); } TEST_F(ValueTrackingTest, isGuaranteedNotToBeUndefOrPoison_assume) { parseAssembly("declare i1 @f_i1()\n" "declare i32 @f_i32()\n" "declare void @llvm.assume(i1)\n" "define void @test() {\n" " %A = call i32 @f_i32()\n" " %cond = call i1 @f_i1()\n" " %CxtI = add i32 0, 0\n" " br i1 %cond, label %BB1, label %EXIT\n" "BB1:\n" " %CxtI2 = add i32 0, 0\n" " %cond2 = call i1 @f_i1()\n" " call void @llvm.assume(i1 true) [ \"noundef\"(i32 %A) ]\n" " br i1 %cond2, label %BB2, label %EXIT\n" "BB2:\n" " %CxtI3 = add i32 0, 0\n" " ret void\n" "EXIT:\n" " ret void\n" "}"); AssumptionCache AC(*F); DominatorTree DT(*F); EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI, &DT)); EXPECT_FALSE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI2, &DT)); EXPECT_TRUE(isGuaranteedNotToBeUndefOrPoison(A, &AC, CxtI3, &DT)); } TEST(ValueTracking, canCreatePoisonOrUndef) { std::string AsmHead = "declare i32 @g(i32)\n" "define void @f(i32 %x, i32 %y, float %fx, float %fy, i1 %cond, " "<4 x i32> %vx, <4 x i32> %vx2, %svx, i8* %p) {\n"; std::string AsmTail = " ret void\n}"; // (can create poison?, can create undef?, IR instruction) SmallVector, std::string>, 32> Data = { {{false, false}, "add i32 %x, %y"}, {{true, false}, "add nsw nuw i32 %x, %y"}, {{true, false}, "shl i32 %x, %y"}, {{true, false}, "shl <4 x i32> %vx, %vx2"}, {{true, false}, "shl nsw i32 %x, %y"}, {{true, false}, "shl nsw <4 x i32> %vx, "}, {{false, false}, "shl i32 %x, 31"}, {{true, false}, "shl i32 %x, 32"}, {{false, false}, "shl <4 x i32> %vx, "}, {{true, false}, "shl <4 x i32> %vx, "}, {{true, false}, "ashr i32 %x, %y"}, {{true, false}, "ashr exact i32 %x, %y"}, {{false, false}, "ashr i32 %x, 31"}, {{true, false}, "ashr exact i32 %x, 31"}, {{false, false}, "ashr <4 x i32> %vx, "}, {{true, false}, "ashr <4 x i32> %vx, "}, {{true, false}, "ashr exact <4 x i32> %vx, "}, {{true, false}, "lshr i32 %x, %y"}, {{true, false}, "lshr exact i32 %x, 31"}, {{false, false}, "udiv i32 %x, %y"}, {{true, false}, "udiv exact i32 %x, %y"}, {{false, false}, "getelementptr i8, i8* %p, i32 %x"}, {{true, false}, "getelementptr inbounds i8, i8* %p, i32 %x"}, {{true, false}, "fneg nnan float %fx"}, {{false, false}, "fneg float %fx"}, {{false, false}, "fadd float %fx, %fy"}, {{true, false}, "fadd nnan float %fx, %fy"}, {{false, false}, "urem i32 %x, %y"}, {{true, false}, "fptoui float %fx to i32"}, {{true, false}, "fptosi float %fx to i32"}, {{false, false}, "bitcast float %fx to i32"}, {{false, false}, "select i1 %cond, i32 %x, i32 %y"}, {{true, false}, "select nnan i1 %cond, float %fx, float %fy"}, {{true, false}, "extractelement <4 x i32> %vx, i32 %x"}, {{false, false}, "extractelement <4 x i32> %vx, i32 3"}, {{true, false}, "extractelement %svx, i32 4"}, {{true, false}, "insertelement <4 x i32> %vx, i32 %x, i32 %y"}, {{false, false}, "insertelement <4 x i32> %vx, i32 %x, i32 3"}, {{true, false}, "insertelement %svx, i32 %x, i32 4"}, {{false, false}, "freeze i32 %x"}, {{false, false}, "shufflevector <4 x i32> %vx, <4 x i32> %vx2, " "<4 x i32> "}, {{false, true}, "shufflevector <4 x i32> %vx, <4 x i32> %vx2, " "<4 x i32> "}, {{false, true}, "shufflevector %svx, " " %svx, undef"}, {{true, false}, "call i32 @g(i32 %x)"}, {{false, false}, "call noundef i32 @g(i32 %x)"}, {{true, false}, "fcmp nnan oeq float %fx, %fy"}, {{false, false}, "fcmp oeq float %fx, %fy"}}; std::string AssemblyStr = AsmHead; for (auto &Itm : Data) AssemblyStr += Itm.second + "\n"; AssemblyStr += AsmTail; LLVMContext Context; SMDiagnostic Error; auto M = parseAssemblyString(AssemblyStr, Error, Context); assert(M && "Bad assembly?"); auto *F = M->getFunction("f"); assert(F && "Bad assembly?"); auto &BB = F->getEntryBlock(); int Index = 0; for (auto &I : BB) { if (isa(&I)) break; bool Poison = Data[Index].first.first; bool Undef = Data[Index].first.second; EXPECT_EQ(canCreatePoison(cast(&I)), Poison) << "Incorrect answer of canCreatePoison at instruction " << Index << " = " << I; EXPECT_EQ(canCreateUndefOrPoison(cast(&I)), Undef || Poison) << "Incorrect answer of canCreateUndef at instruction " << Index << " = " << I; Index++; } } TEST_F(ValueTrackingTest, computePtrAlignment) { parseAssembly("declare i1 @f_i1()\n" "declare i8* @f_i8p()\n" "declare void @llvm.assume(i1)\n" "define void @test() {\n" " %A = call i8* @f_i8p()\n" " %cond = call i1 @f_i1()\n" " %CxtI = add i32 0, 0\n" " br i1 %cond, label %BB1, label %EXIT\n" "BB1:\n" " %CxtI2 = add i32 0, 0\n" " %cond2 = call i1 @f_i1()\n" " call void @llvm.assume(i1 true) [ \"align\"(i8* %A, i64 16) ]\n" " br i1 %cond2, label %BB2, label %EXIT\n" "BB2:\n" " %CxtI3 = add i32 0, 0\n" " ret void\n" "EXIT:\n" " ret void\n" "}"); AssumptionCache AC(*F); DominatorTree DT(*F); DataLayout DL = M->getDataLayout(); EXPECT_EQ(getKnownAlignment(A, DL, CxtI, &AC, &DT), Align(1)); EXPECT_EQ(getKnownAlignment(A, DL, CxtI2, &AC, &DT), Align(1)); EXPECT_EQ(getKnownAlignment(A, DL, CxtI3, &AC, &DT), Align(16)); } TEST_F(ComputeKnownBitsTest, ComputeKnownBits) { parseAssembly( "define i32 @test(i32 %a, i32 %b) {\n" " %ash = mul i32 %a, 8\n" " %aad = add i32 %ash, 7\n" " %aan = and i32 %aad, 4095\n" " %bsh = shl i32 %b, 4\n" " %bad = or i32 %bsh, 6\n" " %ban = and i32 %bad, 4095\n" " %A = mul i32 %aan, %ban\n" " ret i32 %A\n" "}\n"); expectKnownBits(/*zero*/ 4278190085u, /*one*/ 10u); } TEST_F(ComputeKnownBitsTest, ComputeKnownMulBits) { parseAssembly( "define i32 @test(i32 %a, i32 %b) {\n" " %aa = shl i32 %a, 5\n" " %bb = shl i32 %b, 5\n" " %aaa = or i32 %aa, 24\n" " %bbb = or i32 %bb, 28\n" " %A = mul i32 %aaa, %bbb\n" " ret i32 %A\n" "}\n"); expectKnownBits(/*zero*/ 95u, /*one*/ 32u); } TEST_F(ComputeKnownBitsTest, KnownNonZeroShift) { // %q is known nonzero without known bits. // Because %q is nonzero, %A[0] is known to be zero. parseAssembly( "define i8 @test(i8 %p, i8* %pq) {\n" " %q = load i8, i8* %pq, !range !0\n" " %A = shl i8 %p, %q\n" " ret i8 %A\n" "}\n" "!0 = !{ i8 1, i8 5 }\n"); expectKnownBits(/*zero*/ 1u, /*one*/ 0u); } TEST_F(ComputeKnownBitsTest, ComputeKnownFshl) { // fshl(....1111....0000, 00..1111........, 6) // = 11....000000..11 parseAssembly( "define i16 @test(i16 %a, i16 %b) {\n" " %aa = shl i16 %a, 4\n" " %bb = lshr i16 %b, 2\n" " %aaa = or i16 %aa, 3840\n" " %bbb = or i16 %bb, 3840\n" " %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 6)\n" " ret i16 %A\n" "}\n" "declare i16 @llvm.fshl.i16(i16, i16, i16)\n"); expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u); } TEST_F(ComputeKnownBitsTest, ComputeKnownFshr) { // fshr(....1111....0000, 00..1111........, 26) // = 11....000000..11 parseAssembly( "define i16 @test(i16 %a, i16 %b) {\n" " %aa = shl i16 %a, 4\n" " %bb = lshr i16 %b, 2\n" " %aaa = or i16 %aa, 3840\n" " %bbb = or i16 %bb, 3840\n" " %A = call i16 @llvm.fshr.i16(i16 %aaa, i16 %bbb, i16 26)\n" " ret i16 %A\n" "}\n" "declare i16 @llvm.fshr.i16(i16, i16, i16)\n"); expectKnownBits(/*zero*/ 1008u, /*one*/ 49155u); } TEST_F(ComputeKnownBitsTest, ComputeKnownFshlZero) { // fshl(....1111....0000, 00..1111........, 0) // = ....1111....0000 parseAssembly( "define i16 @test(i16 %a, i16 %b) {\n" " %aa = shl i16 %a, 4\n" " %bb = lshr i16 %b, 2\n" " %aaa = or i16 %aa, 3840\n" " %bbb = or i16 %bb, 3840\n" " %A = call i16 @llvm.fshl.i16(i16 %aaa, i16 %bbb, i16 0)\n" " ret i16 %A\n" "}\n" "declare i16 @llvm.fshl.i16(i16, i16, i16)\n"); expectKnownBits(/*zero*/ 15u, /*one*/ 3840u); } TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatLeadingOnes) { // uadd.sat(1111...1, ........) // = 1111.... parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %aa = or i8 %a, 241\n" " %A = call i8 @llvm.uadd.sat.i8(i8 %aa, i8 %b)\n" " ret i8 %A\n" "}\n" "declare i8 @llvm.uadd.sat.i8(i8, i8)\n"); expectKnownBits(/*zero*/ 0u, /*one*/ 240u); } TEST_F(ComputeKnownBitsTest, ComputeKnownUAddSatOnesPreserved) { // uadd.sat(00...011, .1...110) // = .......1 parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %aa = or i8 %a, 3\n" " %aaa = and i8 %aa, 59\n" " %bb = or i8 %b, 70\n" " %bbb = and i8 %bb, 254\n" " %A = call i8 @llvm.uadd.sat.i8(i8 %aaa, i8 %bbb)\n" " ret i8 %A\n" "}\n" "declare i8 @llvm.uadd.sat.i8(i8, i8)\n"); expectKnownBits(/*zero*/ 0u, /*one*/ 1u); } TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatLHSLeadingZeros) { // usub.sat(0000...0, ........) // = 0000.... parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %aa = and i8 %a, 14\n" " %A = call i8 @llvm.usub.sat.i8(i8 %aa, i8 %b)\n" " ret i8 %A\n" "}\n" "declare i8 @llvm.usub.sat.i8(i8, i8)\n"); expectKnownBits(/*zero*/ 240u, /*one*/ 0u); } TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatRHSLeadingOnes) { // usub.sat(........, 1111...1) // = 0000.... parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %bb = or i8 %a, 241\n" " %A = call i8 @llvm.usub.sat.i8(i8 %a, i8 %bb)\n" " ret i8 %A\n" "}\n" "declare i8 @llvm.usub.sat.i8(i8, i8)\n"); expectKnownBits(/*zero*/ 240u, /*one*/ 0u); } TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatZerosPreserved) { // usub.sat(11...011, .1...110) // = ......0. parseAssembly( "define i8 @test(i8 %a, i8 %b) {\n" " %aa = or i8 %a, 195\n" " %aaa = and i8 %aa, 251\n" " %bb = or i8 %b, 70\n" " %bbb = and i8 %bb, 254\n" " %A = call i8 @llvm.usub.sat.i8(i8 %aaa, i8 %bbb)\n" " ret i8 %A\n" "}\n" "declare i8 @llvm.usub.sat.i8(i8, i8)\n"); expectKnownBits(/*zero*/ 2u, /*one*/ 0u); } TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntTrunc) { // ptrtoint truncates the pointer type. parseAssembly( "define void @test(i8** %p) {\n" " %A = load i8*, i8** %p\n" " %i = ptrtoint i8* %A to i32\n" " %m = and i32 %i, 31\n" " %c = icmp eq i32 %m, 0\n" " call void @llvm.assume(i1 %c)\n" " ret void\n" "}\n" "declare void @llvm.assume(i1)\n"); AssumptionCache AC(*F); KnownBits Known = computeKnownBits( A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), 31u); EXPECT_EQ(Known.One.getZExtValue(), 0u); } TEST_F(ComputeKnownBitsTest, ComputeKnownBitsPtrToIntZext) { // ptrtoint zero extends the pointer type. parseAssembly( "define void @test(i8** %p) {\n" " %A = load i8*, i8** %p\n" " %i = ptrtoint i8* %A to i128\n" " %m = and i128 %i, 31\n" " %c = icmp eq i128 %m, 0\n" " call void @llvm.assume(i1 %c)\n" " ret void\n" "}\n" "declare void @llvm.assume(i1)\n"); AssumptionCache AC(*F); KnownBits Known = computeKnownBits( A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), 31u); EXPECT_EQ(Known.One.getZExtValue(), 0u); } TEST_F(ComputeKnownBitsTest, ComputeKnownBitsFreeze) { parseAssembly("define void @test() {\n" " %m = call i32 @any_num()\n" " %A = freeze i32 %m\n" " %n = and i32 %m, 31\n" " %c = icmp eq i32 %n, 0\n" " call void @llvm.assume(i1 %c)\n" " ret void\n" "}\n" "declare void @llvm.assume(i1)\n" "declare i32 @any_num()\n"); AssumptionCache AC(*F); KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), 31u); EXPECT_EQ(Known.One.getZExtValue(), 0u); } TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRange) { parseAssembly("define void @test(i64* %p) {\n" " %A = load i64, i64* %p, !range !{i64 64, i64 65536}\n" " %APlus512 = add i64 %A, 512\n" " %c = icmp ugt i64 %APlus512, 523\n" " call void @llvm.assume(i1 %c)\n" " ret void\n" "}\n" "declare void @llvm.assume(i1)\n"); AssumptionCache AC(*F); KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1)); EXPECT_EQ(Known.One.getZExtValue(), 0u); Instruction &APlus512 = findInstructionByName(F, "APlus512"); Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); // We know of one less zero because 512 may have produced a 1 that // got carried all the way to the first trailing zero. EXPECT_EQ(Known.Zero.getZExtValue(), (~(65536llu - 1)) << 1); EXPECT_EQ(Known.One.getZExtValue(), 0u); // The known range is not precise given computeKnownBits works // with the masks of zeros and ones, not the ranges. EXPECT_EQ(Known.getMinValue(), 0u); EXPECT_EQ(Known.getMaxValue(), 131071); } // 512 + [32, 64) doesn't produce overlapping bits. // Make sure we get all the individual bits properly. TEST_F(ComputeKnownBitsTest, ComputeKnownBitsAddWithRangeNoOverlap) { parseAssembly("define void @test(i64* %p) {\n" " %A = load i64, i64* %p, !range !{i64 32, i64 64}\n" " %APlus512 = add i64 %A, 512\n" " %c = icmp ugt i64 %APlus512, 523\n" " call void @llvm.assume(i1 %c)\n" " ret void\n" "}\n" "declare void @llvm.assume(i1)\n"); AssumptionCache AC(*F); KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1)); EXPECT_EQ(Known.One.getZExtValue(), 32u); Instruction &APlus512 = findInstructionByName(F, "APlus512"); Known = computeKnownBits(&APlus512, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1)); EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u); // The known range is not precise given computeKnownBits works // with the masks of zeros and ones, not the ranges. EXPECT_EQ(Known.getMinValue(), 544); EXPECT_EQ(Known.getMaxValue(), 575); } TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRange) { parseAssembly( "define void @test(i64* %p) {\n" " %A = load i64, i64* %p, !range !{i64 64, i64 65536}\n" " %APtr = inttoptr i64 %A to float*" " %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n" " %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n" " call void @llvm.assume(i1 %c)\n" " ret void\n" "}\n" "declare void @llvm.assume(i1)\n"); AssumptionCache AC(*F); KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1)); EXPECT_EQ(Known.One.getZExtValue(), 0u); Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512"); Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); // We know of one less zero because 512 may have produced a 1 that // got carried all the way to the first trailing zero. EXPECT_EQ(Known.Zero.getZExtValue(), ~(65536llu - 1) << 1); EXPECT_EQ(Known.One.getZExtValue(), 0u); // The known range is not precise given computeKnownBits works // with the masks of zeros and ones, not the ranges. EXPECT_EQ(Known.getMinValue(), 0u); EXPECT_EQ(Known.getMaxValue(), 131071); } // 4*128 + [32, 64) doesn't produce overlapping bits. // Make sure we get all the individual bits properly. // This test is useful to check that we account for the scaling factor // in the gep. Indeed, gep float, [32,64), 128 is not 128 + [32,64). TEST_F(ComputeKnownBitsTest, ComputeKnownBitsGEPWithRangeNoOverlap) { parseAssembly( "define void @test(i64* %p) {\n" " %A = load i64, i64* %p, !range !{i64 32, i64 64}\n" " %APtr = inttoptr i64 %A to float*" " %APtrPlus512 = getelementptr float, float* %APtr, i32 128\n" " %c = icmp ugt float* %APtrPlus512, inttoptr (i32 523 to float*)\n" " call void @llvm.assume(i1 %c)\n" " ret void\n" "}\n" "declare void @llvm.assume(i1)\n"); AssumptionCache AC(*F); KnownBits Known = computeKnownBits(A, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), ~(64llu - 1)); EXPECT_EQ(Known.One.getZExtValue(), 32u); Instruction &APtrPlus512 = findInstructionByName(F, "APtrPlus512"); Known = computeKnownBits(&APtrPlus512, M->getDataLayout(), /* Depth */ 0, &AC, F->front().getTerminator()); EXPECT_EQ(Known.Zero.getZExtValue(), ~512llu & ~(64llu - 1)); EXPECT_EQ(Known.One.getZExtValue(), 512u | 32u); // The known range is not precise given computeKnownBits works // with the masks of zeros and ones, not the ranges. EXPECT_EQ(Known.getMinValue(), 544); EXPECT_EQ(Known.getMaxValue(), 575); } class IsBytewiseValueTest : public ValueTrackingTest, public ::testing::WithParamInterface< std::pair> { protected: }; const std::pair IsBytewiseValueTests[] = { { "i8 0", "i48* null", }, { "i8 undef", "i48* undef", }, { "i8 0", "i8 zeroinitializer", }, { "i8 0", "i8 0", }, { "i8 -86", "i8 -86", }, { "i8 -1", "i8 -1", }, { "i8 undef", "i16 undef", }, { "i8 0", "i16 0", }, { "", "i16 7", }, { "i8 -86", "i16 -21846", }, { "i8 -1", "i16 -1", }, { "i8 0", "i48 0", }, { "i8 -1", "i48 -1", }, { "i8 0", "i49 0", }, { "", "i49 -1", }, { "i8 0", "half 0xH0000", }, { "i8 -85", "half 0xHABAB", }, { "i8 0", "float 0.0", }, { "i8 -1", "float 0xFFFFFFFFE0000000", }, { "i8 0", "double 0.0", }, { "i8 -15", "double 0xF1F1F1F1F1F1F1F1", }, { "i8 undef", "i16* undef", }, { "i8 0", "i16* inttoptr (i64 0 to i16*)", }, { "i8 -1", "i16* inttoptr (i64 -1 to i16*)", }, { "i8 -86", "i16* inttoptr (i64 -6148914691236517206 to i16*)", }, { "", "i16* inttoptr (i48 -1 to i16*)", }, { "i8 -1", "i16* inttoptr (i96 -1 to i16*)", }, { "i8 undef", "[0 x i8] zeroinitializer", }, { "i8 undef", "[0 x i8] undef", }, { "i8 undef", "[5 x [0 x i8]] zeroinitializer", }, { "i8 undef", "[5 x [0 x i8]] undef", }, { "i8 0", "[6 x i8] zeroinitializer", }, { "i8 undef", "[6 x i8] undef", }, { "i8 1", "[5 x i8] [i8 1, i8 1, i8 1, i8 1, i8 1]", }, { "", "[5 x i64] [i64 1, i64 1, i64 1, i64 1, i64 1]", }, { "i8 -1", "[5 x i64] [i64 -1, i64 -1, i64 -1, i64 -1, i64 -1]", }, { "", "[4 x i8] [i8 1, i8 2, i8 1, i8 1]", }, { "i8 1", "[4 x i8] [i8 1, i8 undef, i8 1, i8 1]", }, { "i8 0", "<6 x i8> zeroinitializer", }, { "i8 undef", "<6 x i8> undef", }, { "i8 1", "<5 x i8> ", }, { "", "<5 x i64> ", }, { "i8 -1", "<5 x i64> ", }, { "", "<4 x i8> ", }, { "i8 5", "<2 x i8> < i8 5, i8 undef >", }, { "i8 0", "[2 x [2 x i16]] zeroinitializer", }, { "i8 undef", "[2 x [2 x i16]] undef", }, { "i8 -86", "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], " "[2 x i16] [i16 -21846, i16 -21846]]", }, { "", "[2 x [2 x i16]] [[2 x i16] [i16 -21846, i16 -21846], " "[2 x i16] [i16 -21836, i16 -21846]]", }, { "i8 undef", "{ } zeroinitializer", }, { "i8 undef", "{ } undef", }, { "i8 undef", "{ {}, {} } zeroinitializer", }, { "i8 undef", "{ {}, {} } undef", }, { "i8 0", "{i8, i64, i16*} zeroinitializer", }, { "i8 undef", "{i8, i64, i16*} undef", }, { "i8 -86", "{i8, i64, i16*} {i8 -86, i64 -6148914691236517206, i16* undef}", }, { "", "{i8, i64, i16*} {i8 86, i64 -6148914691236517206, i16* undef}", }, }; INSTANTIATE_TEST_CASE_P(IsBytewiseValueParamTests, IsBytewiseValueTest, ::testing::ValuesIn(IsBytewiseValueTests),); TEST_P(IsBytewiseValueTest, IsBytewiseValue) { auto M = parseModule(std::string("@test = global ") + GetParam().second); GlobalVariable *GV = dyn_cast(M->getNamedValue("test")); Value *Actual = isBytewiseValue(GV->getInitializer(), M->getDataLayout()); std::string Buff; raw_string_ostream S(Buff); if (Actual) S << *Actual; EXPECT_EQ(GetParam().first, S.str()); } TEST_F(ValueTrackingTest, ComputeConstantRange) { { // Assumptions: // * stride >= 5 // * stride < 10 // // stride = [5, 10) auto M = parseModule(R"( declare void @llvm.assume(i1) define i32 @test(i32 %stride) { %gt = icmp uge i32 %stride, 5 call void @llvm.assume(i1 %gt) %lt = icmp ult i32 %stride, 10 call void @llvm.assume(i1 %lt) %stride.plus.one = add nsw nuw i32 %stride, 1 ret i32 %stride.plus.one })"); Function *F = M->getFunction("test"); AssumptionCache AC(*F); Value *Stride = &*F->arg_begin(); ConstantRange CR1 = computeConstantRange(Stride, true, &AC, nullptr); EXPECT_TRUE(CR1.isFullSet()); Instruction *I = &findInstructionByName(F, "stride.plus.one"); ConstantRange CR2 = computeConstantRange(Stride, true, &AC, I); EXPECT_EQ(5, CR2.getLower()); EXPECT_EQ(10, CR2.getUpper()); } { // Assumptions: // * stride >= 5 // * stride < 200 // * stride == 99 // // stride = [99, 100) auto M = parseModule(R"( declare void @llvm.assume(i1) define i32 @test(i32 %stride) { %gt = icmp uge i32 %stride, 5 call void @llvm.assume(i1 %gt) %lt = icmp ult i32 %stride, 200 call void @llvm.assume(i1 %lt) %eq = icmp eq i32 %stride, 99 call void @llvm.assume(i1 %eq) %stride.plus.one = add nsw nuw i32 %stride, 1 ret i32 %stride.plus.one })"); Function *F = M->getFunction("test"); AssumptionCache AC(*F); Value *Stride = &*F->arg_begin(); Instruction *I = &findInstructionByName(F, "stride.plus.one"); ConstantRange CR = computeConstantRange(Stride, true, &AC, I); EXPECT_EQ(99, *CR.getSingleElement()); } { // Assumptions: // * stride >= 5 // * stride >= 50 // * stride < 100 // * stride < 200 // // stride = [50, 100) auto M = parseModule(R"( declare void @llvm.assume(i1) define i32 @test(i32 %stride, i1 %cond) { %gt = icmp uge i32 %stride, 5 call void @llvm.assume(i1 %gt) %gt.2 = icmp uge i32 %stride, 50 call void @llvm.assume(i1 %gt.2) br i1 %cond, label %bb1, label %bb2 bb1: %lt = icmp ult i32 %stride, 200 call void @llvm.assume(i1 %lt) %lt.2 = icmp ult i32 %stride, 100 call void @llvm.assume(i1 %lt.2) %stride.plus.one = add nsw nuw i32 %stride, 1 ret i32 %stride.plus.one bb2: ret i32 0 })"); Function *F = M->getFunction("test"); AssumptionCache AC(*F); Value *Stride = &*F->arg_begin(); Instruction *GT2 = &findInstructionByName(F, "gt.2"); ConstantRange CR = computeConstantRange(Stride, true, &AC, GT2); EXPECT_EQ(5, CR.getLower()); EXPECT_EQ(0, CR.getUpper()); Instruction *I = &findInstructionByName(F, "stride.plus.one"); ConstantRange CR2 = computeConstantRange(Stride, true, &AC, I); EXPECT_EQ(50, CR2.getLower()); EXPECT_EQ(100, CR2.getUpper()); } { // Assumptions: // * stride > 5 // * stride < 5 // // stride = empty range, as the assumptions contradict each other. auto M = parseModule(R"( declare void @llvm.assume(i1) define i32 @test(i32 %stride, i1 %cond) { %gt = icmp ugt i32 %stride, 5 call void @llvm.assume(i1 %gt) %lt = icmp ult i32 %stride, 5 call void @llvm.assume(i1 %lt) %stride.plus.one = add nsw nuw i32 %stride, 1 ret i32 %stride.plus.one })"); Function *F = M->getFunction("test"); AssumptionCache AC(*F); Value *Stride = &*F->arg_begin(); Instruction *I = &findInstructionByName(F, "stride.plus.one"); ConstantRange CR = computeConstantRange(Stride, true, &AC, I); EXPECT_TRUE(CR.isEmptySet()); } { // Assumptions: // * x.1 >= 5 // * x.2 < x.1 // // stride = [0, 5) auto M = parseModule(R"( declare void @llvm.assume(i1) define i32 @test(i32 %x.1, i32 %x.2) { %gt = icmp uge i32 %x.1, 5 call void @llvm.assume(i1 %gt) %lt = icmp ult i32 %x.2, %x.1 call void @llvm.assume(i1 %lt) %stride.plus.one = add nsw nuw i32 %x.1, 1 ret i32 %stride.plus.one })"); Function *F = M->getFunction("test"); AssumptionCache AC(*F); Value *X2 = &*std::next(F->arg_begin()); Instruction *I = &findInstructionByName(F, "stride.plus.one"); ConstantRange CR1 = computeConstantRange(X2, true, &AC, I); EXPECT_EQ(0, CR1.getLower()); EXPECT_EQ(5, CR1.getUpper()); // Check the depth cutoff results in a conservative result (full set) by // passing Depth == MaxDepth == 6. ConstantRange CR2 = computeConstantRange(X2, true, &AC, I, 6); EXPECT_TRUE(CR2.isFullSet()); } } struct FindAllocaForValueTestParams { const char *IR; bool AnyOffsetResult; bool ZeroOffsetResult; }; class FindAllocaForValueTest : public ValueTrackingTest, public ::testing::WithParamInterface { protected: }; const FindAllocaForValueTestParams FindAllocaForValueTests[] = { {R"( define void @test() { %a = alloca i64 %r = bitcast i64* %a to i32* ret void })", true, true}, {R"( define void @test() { %a = alloca i32 %r = getelementptr i32, i32* %a, i32 1 ret void })", true, false}, {R"( define void @test() { %a = alloca i32 %r = getelementptr i32, i32* %a, i32 0 ret void })", true, true}, {R"( define void @test(i1 %cond) { entry: %a = alloca i32 br label %bb1 bb1: %r = phi i32* [ %a, %entry ], [ %r, %bb1 ] br i1 %cond, label %bb1, label %exit exit: ret void })", true, true}, {R"( define void @test(i1 %cond) { %a = alloca i32 %r = select i1 %cond, i32* %a, i32* %a ret void })", true, true}, {R"( define void @test(i1 %cond) { %a = alloca i32 %b = alloca i32 %r = select i1 %cond, i32* %a, i32* %b ret void })", false, false}, {R"( define void @test(i1 %cond) { entry: %a = alloca i64 %a32 = bitcast i64* %a to i32* br label %bb1 bb1: %x = phi i32* [ %a32, %entry ], [ %x, %bb1 ] %r = getelementptr i32, i32* %x, i32 1 br i1 %cond, label %bb1, label %exit exit: ret void })", true, false}, {R"( define void @test(i1 %cond) { entry: %a = alloca i64 %a32 = bitcast i64* %a to i32* br label %bb1 bb1: %x = phi i32* [ %a32, %entry ], [ %r, %bb1 ] %r = getelementptr i32, i32* %x, i32 1 br i1 %cond, label %bb1, label %exit exit: ret void })", true, false}, {R"( define void @test(i1 %cond, i64* %a) { entry: %r = bitcast i64* %a to i32* ret void })", false, false}, {R"( define void @test(i1 %cond) { entry: %a = alloca i32 %b = alloca i32 br label %bb1 bb1: %r = phi i32* [ %a, %entry ], [ %b, %bb1 ] br i1 %cond, label %bb1, label %exit exit: ret void })", false, false}, }; TEST_P(FindAllocaForValueTest, findAllocaForValue) { auto M = parseModule(GetParam().IR); Function *F = M->getFunction("test"); Instruction *I = &findInstructionByName(F, "r"); const AllocaInst *AI = findAllocaForValue(I); EXPECT_EQ(!!AI, GetParam().AnyOffsetResult); } TEST_P(FindAllocaForValueTest, findAllocaForValueZeroOffset) { auto M = parseModule(GetParam().IR); Function *F = M->getFunction("test"); Instruction *I = &findInstructionByName(F, "r"); const AllocaInst *AI = findAllocaForValue(I, true); EXPECT_EQ(!!AI, GetParam().ZeroOffsetResult); } INSTANTIATE_TEST_CASE_P(FindAllocaForValueTest, FindAllocaForValueTest, ::testing::ValuesIn(FindAllocaForValueTests), );