[llvm-branch-commits] [llvm] [HLSL][RootSignature] Implement `ResourceRange` as an `IntervalMap` (PR #140957)

[Deric C. via llvm-branch-commits]

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@@ -0,0 +1,177 @@
+//===------ HLSLRootSignatureRangeTest.cpp - RootSignature Range tests ----===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Frontend/HLSL/HLSLRootSignature.h"
+#include "gtest/gtest.h"
+
+using namespace llvm::hlsl::rootsig;
+
+namespace {
+
+TEST(HLSLRootSignatureTest, NoOverlappingInsertTests) {
+  // Ensures that there is never a reported overlap
+  ResourceRange::IMap::Allocator Allocator;
+  ResourceRange Range(Allocator);
+
+  RangeInfo A;
+  A.LowerBound = 0;
+  A.UpperBound = 3;
+  EXPECT_EQ(Range.insert(A), std::nullopt);
+
+  RangeInfo B;
+  B.LowerBound = 4;
+  B.UpperBound = 7;
+  EXPECT_EQ(Range.insert(B), std::nullopt);
+
+  RangeInfo C;
+  C.LowerBound = 10;
+  C.UpperBound = RangeInfo::Unbounded;
+  EXPECT_EQ(Range.insert(C), std::nullopt);
+
+  // A = [0;3]
+  EXPECT_EQ(Range.lookup(0), &A);
+  EXPECT_EQ(Range.lookup(2), &A);
+  EXPECT_EQ(Range.lookup(3), &A);
+
+  // B = [4;7]
+  EXPECT_EQ(Range.lookup(4), &B);
+  EXPECT_EQ(Range.lookup(5), &B);
+  EXPECT_EQ(Range.lookup(7), &B);
+
+  EXPECT_EQ(Range.lookup(8), nullptr);
+  EXPECT_EQ(Range.lookup(9), nullptr);
+
+  // C = [10;unbounded]
+  EXPECT_EQ(Range.lookup(10), &C);
+  EXPECT_EQ(Range.lookup(42), &C);
+  EXPECT_EQ(Range.lookup(98237423), &C);
+  EXPECT_EQ(Range.lookup(RangeInfo::Unbounded), &C);
+}
+
+TEST(HLSLRootSignatureTest, SingleOverlappingInsertTests) {
+  // Ensures that we correctly report an overlap when we insert a range that
+  // overlaps with one other range but does not cover (replace) it
+  ResourceRange::IMap::Allocator Allocator;
+  ResourceRange Range(Allocator);
+
+  RangeInfo A;
+  A.LowerBound = 1;
+  A.UpperBound = 5;
+  EXPECT_EQ(Range.insert(A), std::nullopt);
+
+  RangeInfo B;
+  B.LowerBound = 0;
+  B.UpperBound = 2;
+  EXPECT_EQ(Range.insert(B).value(), &A);
+
+  RangeInfo C;
+  C.LowerBound = 4;
+  C.UpperBound = RangeInfo::Unbounded;
+  EXPECT_EQ(Range.insert(C).value(), &A);
+
+  // A = [1;5]
+  EXPECT_EQ(Range.lookup(1), &A);
+  EXPECT_EQ(Range.lookup(2), &A);
+  EXPECT_EQ(Range.lookup(3), &A);
+  EXPECT_EQ(Range.lookup(4), &A);
+  EXPECT_EQ(Range.lookup(5), &A);
+
+  // B = [0;0]
+  EXPECT_EQ(Range.lookup(0), &B);
+
+  // C = [6; unbounded]
----------------
Icohedron wrote:

```suggestion
  // C = [6;unbounded]
```

https://github.com/llvm/llvm-project/pull/140957