Make ConstantRange::makeICmpRegion handle all the edge cases properly. This

also fixes PR8250.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114972 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nick Lewycky 2010-09-28 18:18:36 +00:00
parent 1a7ca0354a
commit f2d7b7c879
2 changed files with 36 additions and 10 deletions

View File

@ -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())

View File

@ -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