From ed9df8621a85329d9cb607e982a6efb2d9c670f5 Mon Sep 17 00:00:00 2001
From: Paul Walker <paul.walker@arm.com>
Date: Mon, 1 Jun 2020 10:09:58 +0000
Subject: [PATCH] [FileCheck] Implement equality operators for ExpressionValue.

Subscribers: hiraditya, thopre, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81094
---
 llvm/lib/Support/FileCheckImpl.h         | 17 +++++++++++---
 llvm/unittests/Support/FileCheckTest.cpp | 40 ++++++++++++++++++++++++++++++++
 2 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/llvm/lib/Support/FileCheckImpl.h b/llvm/lib/Support/FileCheckImpl.h
index 068de3d..6998df3 100644
--- a/llvm/lib/Support/FileCheckImpl.h
+++ b/llvm/lib/Support/FileCheckImpl.h
@@ -64,8 +64,8 @@ public:
     return Value != Kind::NoFormat && Value == Other.Value;
   }
 
-  bool operator!=(const ExpressionFormat &other) const {
-    return !(*this == other);
+  bool operator!=(const ExpressionFormat &Other) const {
+    return !(*this == Other);
   }
 
   bool operator==(Kind OtherValue) const { return Value == OtherValue; }
@@ -119,8 +119,19 @@ public:
   template <class T>
   explicit ExpressionValue(T Val) : Value(Val), Negative(Val < 0) {}
 
+  bool operator==(const ExpressionValue &Other) const {
+    return Value == Other.Value && isNegative() == Other.isNegative();
+  }
+
+  bool operator!=(const ExpressionValue &Other) const {
+    return !(*this == Other);
+  }
+
   /// Returns true if value is signed and negative, false otherwise.
-  bool isNegative() const { return Negative; }
+  bool isNegative() const {
+    assert((Value != 0 || !Negative) && "Unexpected negative zero!");
+    return Negative;
+  }
 
   /// \returns the value as a signed integer or an error if the value is out of
   /// range.
diff --git a/llvm/unittests/Support/FileCheckTest.cpp b/llvm/unittests/Support/FileCheckTest.cpp
index 54646a0..c549991 100644
--- a/llvm/unittests/Support/FileCheckTest.cpp
+++ b/llvm/unittests/Support/FileCheckTest.cpp
@@ -478,6 +478,46 @@ TEST_F(FileCheckTest, ExpressionValueSubtraction) {
   expectOperationValueResult(operator-, 10, 11, -1);
 }
 
+TEST_F(FileCheckTest, ExpressionValueEquality) {
+  // Test negative and positive value.
+  EXPECT_FALSE(ExpressionValue(5) == ExpressionValue(-3));
+  EXPECT_TRUE(ExpressionValue(5) != ExpressionValue(-3));
+  EXPECT_FALSE(ExpressionValue(-2) == ExpressionValue(6));
+  EXPECT_TRUE(ExpressionValue(-2) != ExpressionValue(6));
+  EXPECT_FALSE(ExpressionValue(-7) == ExpressionValue(7));
+  EXPECT_TRUE(ExpressionValue(-7) != ExpressionValue(7));
+  EXPECT_FALSE(ExpressionValue(4) == ExpressionValue(-4));
+  EXPECT_TRUE(ExpressionValue(4) != ExpressionValue(-4));
+  EXPECT_FALSE(ExpressionValue(MaxUint64) == ExpressionValue(-1));
+  EXPECT_TRUE(ExpressionValue(MaxUint64) != ExpressionValue(-1));
+
+  // Test both negative values.
+  EXPECT_FALSE(ExpressionValue(-2) == ExpressionValue(-7));
+  EXPECT_TRUE(ExpressionValue(-2) != ExpressionValue(-7));
+  EXPECT_TRUE(ExpressionValue(-3) == ExpressionValue(-3));
+  EXPECT_FALSE(ExpressionValue(-3) != ExpressionValue(-3));
+  EXPECT_FALSE(ExpressionValue(MinInt64) == ExpressionValue(-1));
+  EXPECT_TRUE(ExpressionValue(MinInt64) != ExpressionValue(-1));
+  EXPECT_FALSE(ExpressionValue(MinInt64) == ExpressionValue(-0));
+  EXPECT_TRUE(ExpressionValue(MinInt64) != ExpressionValue(-0));
+
+  // Test both positive values.
+  EXPECT_FALSE(ExpressionValue(8) == ExpressionValue(9));
+  EXPECT_TRUE(ExpressionValue(8) != ExpressionValue(9));
+  EXPECT_TRUE(ExpressionValue(1) == ExpressionValue(1));
+  EXPECT_FALSE(ExpressionValue(1) != ExpressionValue(1));
+
+  // Check the signedness of zero doesn't affect equality.
+  EXPECT_TRUE(ExpressionValue(0) == ExpressionValue(0));
+  EXPECT_FALSE(ExpressionValue(0) != ExpressionValue(0));
+  EXPECT_TRUE(ExpressionValue(0) == ExpressionValue(-0));
+  EXPECT_FALSE(ExpressionValue(0) != ExpressionValue(-0));
+  EXPECT_TRUE(ExpressionValue(-0) == ExpressionValue(0));
+  EXPECT_FALSE(ExpressionValue(-0) != ExpressionValue(0));
+  EXPECT_TRUE(ExpressionValue(-0) == ExpressionValue(-0));
+  EXPECT_FALSE(ExpressionValue(-0) != ExpressionValue(-0));
+}
+
 TEST_F(FileCheckTest, Literal) {
   SourceMgr SM;
 
-- 
2.7.4