[llvm] [SandboxVec][Interval] Implement intersection and difference operations (PR #110549)

[via llvm-commits]

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@@ -90,4 +91,161 @@ define void @foo(i8 %v0) {
   auto BBIt = BB->begin();
   for (auto &I : Intvl)
     EXPECT_EQ(&I, &*BBIt++);
+  {
+    // Check equality.
+    EXPECT_TRUE(Empty == Empty);
+    EXPECT_FALSE(Empty == One);
+    EXPECT_TRUE(One == One);
+    sandboxir::Interval<sandboxir::Instruction> Intvl1(I0, I2);
+    sandboxir::Interval<sandboxir::Instruction> Intvl2(I0, I2);
+    EXPECT_TRUE(Intvl1 == Intvl1);
+    EXPECT_TRUE(Intvl1 == Intvl2);
+  }
+  {
+    // Check inequality.
+    EXPECT_FALSE(Empty != Empty);
+    EXPECT_TRUE(Empty != One);
+    EXPECT_FALSE(One != One);
+    sandboxir::Interval<sandboxir::Instruction> Intvl1(I0, I2);
+    sandboxir::Interval<sandboxir::Instruction> Intvl2(I0, I2);
+    EXPECT_FALSE(Intvl1 != Intvl1);
+    EXPECT_FALSE(Intvl1 != Intvl2);
+  }
+  {
+    // Check disjoint().
+    EXPECT_TRUE(Empty.disjoint(Empty));
+    EXPECT_TRUE(One.disjoint(Empty));
+    EXPECT_TRUE(Empty.disjoint(One));
+    sandboxir::Interval<sandboxir::Instruction> Intvl1(I0, I2);
+    sandboxir::Interval<sandboxir::Instruction> Intvl2(I1, Ret);
+    EXPECT_FALSE(Intvl1.disjoint(Intvl2));
+    sandboxir::Interval<sandboxir::Instruction> Intvl3(I2, I2);
+    EXPECT_FALSE(Intvl1.disjoint(Intvl3));
+    EXPECT_TRUE(Intvl1.disjoint(Empty));
+  }
+}
+
+// Helper function for returning a vector of instruction pointers from a range
+// of references.
+template <typename RangeT>
+static SmallVector<sandboxir::Instruction *> getPtrVec(RangeT Range) {
+  SmallVector<sandboxir::Instruction *> PtrVec;
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Sterling-Augustine wrote:

Seems like this might be useful outside of tests, and therefore maybe should go in a utility class?

https://github.com/llvm/llvm-project/pull/110549