[llvm] [ConstantRange][LVI] Add initial support for `multiplyWithNoWrap` (PR #92356)

[Nikita Popov via llvm-commits]

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@@ -1019,6 +1019,99 @@ TEST_F(ConstantRangeTest, Multiply) {
       });
 }
 
+TEST_F(ConstantRangeTest, MultiplyWithNoWrap) {
+  using OBO = OverflowingBinaryOperator;
+
+  EXPECT_EQ(Empty.multiplyWithNoWrap(Some, OBO::NoUnsignedWrap), Empty);
+  EXPECT_EQ(Some.multiplyWithNoWrap(Empty, OBO::NoUnsignedWrap), Empty);
+  EXPECT_EQ(Full.multiplyWithNoWrap(Full, OBO::NoUnsignedWrap), Full);
+  EXPECT_EQ(Full.multiplyWithNoWrap(Some, OBO::NoUnsignedWrap), Full);
+  EXPECT_EQ(Some.multiplyWithNoWrap(Full, OBO::NoUnsignedWrap), Full);
+  EXPECT_EQ(ConstantRange(APInt(4, 0), APInt(4, 2))
+                .multiplyWithNoWrap(ConstantRange(APInt(4, 2), APInt(4, 0)),
+                                    OBO::NoUnsignedWrap),
+            ConstantRange(4, true));
+  EXPECT_EQ(ConstantRange(APInt(4, 1), APInt(4, 5))
+                .multiplyWithNoWrap(ConstantRange(APInt(4, 1), APInt(4, 5)),
+                                    OBO::NoUnsignedWrap),
+            ConstantRange(APInt(4, 1), APInt(4, 0)));
+  EXPECT_EQ(ConstantRange(APInt(8, 254), APInt(8, 0))
+                .multiplyWithNoWrap(ConstantRange(APInt(8, 252), APInt(8, 4)),
+                                    OBO::NoUnsignedWrap),
+            ConstantRange(APInt(8, 250), APInt(8, 9)));
+  EXPECT_EQ(ConstantRange(APInt(8, 254), APInt(8, 255))
+                .multiplyWithNoWrap(ConstantRange(APInt(8, 2), APInt(8, 4)),
+                                    OBO::NoUnsignedWrap),
+            ConstantRange(8, false));
+
+  EXPECT_EQ(Empty.multiplyWithNoWrap(Some, OBO::NoSignedWrap), Empty);
+  EXPECT_EQ(Some.multiplyWithNoWrap(Empty, OBO::NoSignedWrap), Empty);
+  EXPECT_EQ(Full.multiplyWithNoWrap(Full, OBO::NoSignedWrap), Full);
+  EXPECT_EQ(Full.multiplyWithNoWrap(Some, OBO::NoSignedWrap), Full);
+  EXPECT_EQ(Some.multiplyWithNoWrap(Full, OBO::NoSignedWrap), Full);
+  EXPECT_EQ(ConstantRange(APInt(4, 0), APInt(4, 4))
+                .multiplyWithNoWrap(ConstantRange(APInt(4, -5), APInt(4, 4)),
+                                    OBO::NoSignedWrap),
+            ConstantRange(4, true));
+  EXPECT_EQ(ConstantRange(APInt(4, 0), APInt(4, 3))
+                .multiplyWithNoWrap(ConstantRange(APInt(4, 0), APInt(4, 5)),
+                                    OBO::NoSignedWrap),
+            ConstantRange(APInt(4, 0), APInt(4, -8)));
+  EXPECT_EQ(
+      ConstantRange(APInt(8, 3), APInt(8, -11))
+          .multiplyWithNoWrap(ConstantRange(APInt(8, -1)), OBO::NoSignedWrap),
+      ConstantRange(APInt(8, 12), APInt(8, -2)));
+  EXPECT_EQ(ConstantRange(APInt(8, 254), APInt(8, 255))
+                .multiplyWithNoWrap(ConstantRange(APInt(8, 100), APInt(8, 121)),
+                                    OBO::NoSignedWrap),
+            ConstantRange(8, false));
+
+  auto CheckCorrectnessOnly = [](const ConstantRange &, const ConstantRange &) {
+    return false;
+  };
+
+  TestBinaryOpExhaustive(
+      [](const ConstantRange &CR1, const ConstantRange &CR2) {
+        return CR1.multiplyWithNoWrap(CR2, OBO::NoUnsignedWrap);
+      },
+      [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
+        bool IsOverflow;
+        APInt Res = N1.umul_ov(N2, IsOverflow);
+        if (IsOverflow) {
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nikic wrote:

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https://github.com/llvm/llvm-project/pull/92356