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ValueTracking: Use fcAllFlags for unknown value #66393

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Merged
merged 1 commit into from
Oct 5, 2023
Merged

ValueTracking: Use fcAllFlags for unknown value #66393

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16 changes: 8 additions & 8 deletions llvm/lib/Analysis/ValueTracking.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -4003,7 +4003,7 @@ std::pair<Value *, FPClassTest> llvm::fcmpToClassTest(FCmpInst::Predicate Pred,
bool LookThroughSrc) {
const APFloat *ConstRHS;
if (!match(RHS, m_APFloatAllowUndef(ConstRHS)))
return {nullptr, fcNone};
return {nullptr, fcAllFlags};

return fcmpToClassTest(Pred, F, LHS, ConstRHS, LookThroughSrc);
}
Expand All @@ -4025,7 +4025,7 @@ llvm::fcmpToClassTest(FCmpInst::Predicate Pred, const Function &F, Value *LHS,
// TODO: Handle DAZ by expanding masks to cover subnormal cases.
if (Pred != FCmpInst::FCMP_ORD && Pred != FCmpInst::FCMP_UNO &&
!inputDenormalIsIEEE(F, LHS->getType()))
return {nullptr, fcNone};
return {nullptr, fcAllFlags};

switch (Pred) {
case FCmpInst::FCMP_OEQ: // Match x == 0.0
Expand Down Expand Up @@ -4062,7 +4062,7 @@ llvm::fcmpToClassTest(FCmpInst::Predicate Pred, const Function &F, Value *LHS,
break;
}

return {nullptr, fcNone};
return {nullptr, fcAllFlags};
}

Value *Src = LHS;
Expand Down Expand Up @@ -4146,7 +4146,7 @@ llvm::fcmpToClassTest(FCmpInst::Predicate Pred, const Function &F, Value *LHS,
case FCmpInst::FCMP_OGE:
case FCmpInst::FCMP_ULT: {
if (ConstRHS->isNegative()) // TODO
return {nullptr, fcNone};
return {nullptr, fcAllFlags};

// fcmp oge fabs(x), +inf -> fcInf
// fcmp oge x, +inf -> fcPosInf
Expand All @@ -4160,14 +4160,14 @@ llvm::fcmpToClassTest(FCmpInst::Predicate Pred, const Function &F, Value *LHS,
case FCmpInst::FCMP_OGT:
case FCmpInst::FCMP_ULE: {
if (ConstRHS->isNegative())
return {nullptr, fcNone};
return {nullptr, fcAllFlags};

// No value is ordered and greater than infinity.
Mask = fcNone;
break;
}
default:
return {nullptr, fcNone};
return {nullptr, fcAllFlags};
}
} else if (ConstRHS->isSmallestNormalized() && !ConstRHS->isNegative()) {
// Match pattern that's used in __builtin_isnormal.
Expand Down Expand Up @@ -4196,14 +4196,14 @@ llvm::fcmpToClassTest(FCmpInst::Predicate Pred, const Function &F, Value *LHS,
break;
}
default:
return {nullptr, fcNone};
return {nullptr, fcAllFlags};
}
} else if (ConstRHS->isNaN()) {
// fcmp o__ x, nan -> false
// fcmp u__ x, nan -> true
Mask = fcNone;
} else
return {nullptr, fcNone};
return {nullptr, fcAllFlags};

// Invert the comparison for the unordered cases.
if (FCmpInst::isUnordered(Pred))
Expand Down
8 changes: 4 additions & 4 deletions llvm/unittests/Analysis/ValueTrackingTest.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1848,13 +1848,13 @@ TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_NInf) {
fcmpToClassTest(CmpInst::FCMP_OGT, *A3->getFunction(), A3->getOperand(0),
A3->getOperand(1));
EXPECT_EQ(nullptr, OgtVal);
EXPECT_EQ(fcNone, OgtClass);
EXPECT_EQ(fcAllFlags, OgtClass);

auto [UleVal, UleClass] =
fcmpToClassTest(CmpInst::FCMP_ULE, *A4->getFunction(), A4->getOperand(0),
A4->getOperand(1));
EXPECT_EQ(nullptr, UleVal);
EXPECT_EQ(fcNone, UleClass);
EXPECT_EQ(fcAllFlags, UleClass);
}

TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_PInf) {
Expand All @@ -1881,13 +1881,13 @@ TEST_F(ComputeKnownFPClassTest, FCmpToClassTest_PInf) {
fcmpToClassTest(CmpInst::FCMP_OLE, *A3->getFunction(), A3->getOperand(0),
A3->getOperand(1));
EXPECT_EQ(nullptr, OleVal);
EXPECT_EQ(fcNone, OleClass);
EXPECT_EQ(fcAllFlags, OleClass);

auto [UgtVal, UgtClass] =
fcmpToClassTest(CmpInst::FCMP_UGT, *A4->getFunction(), A4->getOperand(0),
A4->getOperand(1));
EXPECT_EQ(nullptr, UgtVal);
EXPECT_EQ(fcNone, UgtClass);
EXPECT_EQ(fcAllFlags, UgtClass);
}

TEST_F(ComputeKnownFPClassTest, SqrtNszSignBit) {
Expand Down