diff options
| -rw-r--r-- | lib/Support/ConstantRange.cpp | 8 | ||||
| -rw-r--r-- | unittests/Support/ConstantRangeTest.cpp | 4 |
2 files changed, 10 insertions, 2 deletions
diff --git a/lib/Support/ConstantRange.cpp b/lib/Support/ConstantRange.cpp index a3f2297..720ef36 100644 --- a/lib/Support/ConstantRange.cpp +++ b/lib/Support/ConstantRange.cpp @@ -427,9 +427,13 @@ ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const { unsigned SrcTySize = getBitWidth(); assert(SrcTySize < DstTySize && "Not a value extension"); - if (isFullSet() || isWrappedSet()) + if (isFullSet() || isWrappedSet()) { // Change into [0, 1 << src bit width) - return ConstantRange(APInt(DstTySize,0), APInt(DstTySize,1).shl(SrcTySize)); + APInt LowerExt(DstTySize, 0); + if (!Upper) // special case: [X, 0) -- not really wrapping around + LowerExt = Lower.zext(DstTySize); + return ConstantRange(LowerExt, APInt(DstTySize, 1).shl(SrcTySize)); + } return ConstantRange(Lower.zext(DstTySize), Upper.zext(DstTySize)); } diff --git a/unittests/Support/ConstantRangeTest.cpp b/unittests/Support/ConstantRangeTest.cpp index 7d4055f..263f93c 100644 --- a/unittests/Support/ConstantRangeTest.cpp +++ b/unittests/Support/ConstantRangeTest.cpp @@ -193,6 +193,10 @@ TEST_F(ConstantRangeTest, ZExt) { EXPECT_EQ(ZSome, ConstantRange(Some.getLower().zext(20), Some.getUpper().zext(20))); EXPECT_EQ(ZWrap, ConstantRange(APInt(20, 0), APInt(20, 0x10000))); + + // zext([5, 0), 3->7) = [5, 8) + ConstantRange FiveZero(APInt(3, 5), APInt(3, 0)); + EXPECT_EQ(FiveZero.zeroExtend(7), ConstantRange(APInt(7, 5), APInt(7, 8))); } TEST_F(ConstantRangeTest, SExt) { |