From e6eef49f05dadd781a708e68c2fc91ff5aff64a1 Mon Sep 17 00:00:00 2001 From: Nikita Popov Date: Tue, 26 Mar 2019 22:37:26 +0000 Subject: [PATCH] [ConstantRange] Exclude full set from isSignWrappedSet() Split off from D59749. This uses a simpler and more efficient implementation of isSignWrappedSet(), and considers full sets as non-wrapped, to be consistent with isWrappedSet(). Otherwise the behavior is unchanged. There are currently only two users of this function and both already check for isFullSet() || isSignWrappedSet(), so this is not going to cause a change in overall behavior. Differential Revision: https://reviews.llvm.org/D59848 llvm-svn: 357039 --- llvm/include/llvm/IR/ConstantRange.h | 6 ++++-- llvm/lib/IR/ConstantRange.cpp | 3 +-- llvm/unittests/IR/ConstantRangeTest.cpp | 2 +- 3 files changed, 6 insertions(+), 5 deletions(-) diff --git a/llvm/include/llvm/IR/ConstantRange.h b/llvm/include/llvm/IR/ConstantRange.h index 11481a88fbfc..3ac853f31618 100644 --- a/llvm/include/llvm/IR/ConstantRange.h +++ b/llvm/include/llvm/IR/ConstantRange.h @@ -167,8 +167,10 @@ public: /// For example: [100, 8). bool isWrappedSet() const; - /// Return true if this set wraps around the INT_MIN of - /// its bitwidth. For example: i8 [120, 140). + /// Return true if this set wraps around the signed domain. Special cases: + /// * Empty set: Not wrapped. + /// * Full set: Not wrapped. + /// * [X, SignedMin) == [X, SignedMax]: Not wrapped. bool isSignWrappedSet() const; /// Return true if the specified value is in the set. diff --git a/llvm/lib/IR/ConstantRange.cpp b/llvm/lib/IR/ConstantRange.cpp index 732f5c03d4ed..0c2a3a865979 100644 --- a/llvm/lib/IR/ConstantRange.cpp +++ b/llvm/lib/IR/ConstantRange.cpp @@ -349,8 +349,7 @@ bool ConstantRange::isWrappedSet() const { } bool ConstantRange::isSignWrappedSet() const { - return contains(APInt::getSignedMaxValue(getBitWidth())) && - contains(APInt::getSignedMinValue(getBitWidth())); + return Lower.sgt(Upper) && !Upper.isMinSignedValue(); } APInt ConstantRange::getSetSize() const { diff --git a/llvm/unittests/IR/ConstantRangeTest.cpp b/llvm/unittests/IR/ConstantRangeTest.cpp index 058f534249e0..c63c6cef7e18 100644 --- a/llvm/unittests/IR/ConstantRangeTest.cpp +++ b/llvm/unittests/IR/ConstantRangeTest.cpp @@ -161,7 +161,7 @@ TEST_F(ConstantRangeTest, GetMinsAndMaxes) { } TEST_F(ConstantRangeTest, SignWrapped) { - EXPECT_TRUE(Full.isSignWrappedSet()); + EXPECT_FALSE(Full.isSignWrappedSet()); EXPECT_FALSE(Empty.isSignWrappedSet()); EXPECT_FALSE(One.isSignWrappedSet()); EXPECT_FALSE(Some.isSignWrappedSet());