diff --git a/lib/Support/ConstantRange.cpp b/lib/Support/ConstantRange.cpp index c89ec9a2aac..7f68fd32ae1 100644 --- a/lib/Support/ConstantRange.cpp +++ b/lib/Support/ConstantRange.cpp @@ -51,6 +51,9 @@ ConstantRange::ConstantRange(const APInt &L, const APInt &U) : ConstantRange ConstantRange::makeICmpRegion(unsigned Pred, const ConstantRange &CR) { + if (CR.isEmptySet()) + return CR; + uint32_t W = CR.getBitWidth(); switch (Pred) { default: assert(!"Invalid ICmp predicate to makeICmpRegion()"); @@ -60,10 +63,18 @@ ConstantRange ConstantRange::makeICmpRegion(unsigned Pred, if (CR.isSingleElement()) return ConstantRange(CR.getUpper(), CR.getLower()); return ConstantRange(W); - case ICmpInst::ICMP_ULT: - return ConstantRange(APInt::getMinValue(W), CR.getUnsignedMax()); - case ICmpInst::ICMP_SLT: - return ConstantRange(APInt::getSignedMinValue(W), CR.getSignedMax()); + case ICmpInst::ICMP_ULT: { + APInt UMax(CR.getUnsignedMax()); + if (UMax.isMinValue()) + return ConstantRange(W, /* empty */ false); + return ConstantRange(APInt::getMinValue(W), UMax); + } + case ICmpInst::ICMP_SLT: { + APInt SMax(CR.getSignedMax()); + if (SMax.isMinSignedValue()) + return ConstantRange(W, /* empty */ false); + return ConstantRange(APInt::getSignedMinValue(W), SMax); + } case ICmpInst::ICMP_ULE: { APInt UMax(CR.getUnsignedMax()); if (UMax.isMaxValue()) @@ -72,15 +83,22 @@ ConstantRange ConstantRange::makeICmpRegion(unsigned Pred, } case ICmpInst::ICMP_SLE: { APInt SMax(CR.getSignedMax()); - if (SMax.isMaxSignedValue() || (SMax+1).isMaxSignedValue()) + if (SMax.isMaxSignedValue()) return ConstantRange(W); return ConstantRange(APInt::getSignedMinValue(W), SMax + 1); } - case ICmpInst::ICMP_UGT: - return ConstantRange(CR.getUnsignedMin() + 1, APInt::getNullValue(W)); - case ICmpInst::ICMP_SGT: - return ConstantRange(CR.getSignedMin() + 1, - APInt::getSignedMinValue(W)); + case ICmpInst::ICMP_UGT: { + APInt UMin(CR.getUnsignedMin()); + if (UMin.isMaxValue()) + return ConstantRange(W, /* empty */ false); + return ConstantRange(UMin + 1, APInt::getNullValue(W)); + } + case ICmpInst::ICMP_SGT: { + APInt SMin(CR.getSignedMin()); + if (SMin.isMaxSignedValue()) + return ConstantRange(W, /* empty */ false); + return ConstantRange(SMin + 1, APInt::getSignedMinValue(W)); + } case ICmpInst::ICMP_UGE: { APInt UMin(CR.getUnsignedMin()); if (UMin.isMinValue()) diff --git a/unittests/Support/ConstantRangeTest.cpp b/unittests/Support/ConstantRangeTest.cpp index 1cedeae50af..19ef9557f45 100644 --- a/unittests/Support/ConstantRangeTest.cpp +++ b/unittests/Support/ConstantRangeTest.cpp @@ -8,6 +8,7 @@ //===----------------------------------------------------------------------===// #include "llvm/Support/ConstantRange.h" +#include "llvm/Instructions.h" #include "gtest/gtest.h" @@ -429,4 +430,11 @@ TEST_F(ConstantRangeTest, Lshr) { EXPECT_EQ(Wrap.lshr(Wrap), Full); } +TEST(ConstantRange, MakeICmpRegion) { + // PR8250 + ConstantRange SMax = ConstantRange(APInt::getSignedMaxValue(32)); + EXPECT_TRUE(ConstantRange::makeICmpRegion(ICmpInst::ICMP_SGT, + SMax).isEmptySet()); +} + } // anonymous namespace