[llvm] [HLSLSemanticSignatures] Implement the stacked packing of elements (PR #218060)

[Finn Plummer via llvm-commits]

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@@ -0,0 +1,342 @@
+//===- HLSLSemanticSignaturePackingTest.cpp -------------------------------===//
+//
+// 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/ADT/SmallVector.h"
+#include "llvm/Frontend/HLSL/SemanticSignaturePacking.h"
+#include "llvm/TargetParser/Triple.h"
+#include "llvm/Testing/Support/Error.h"
+#include "gtest/gtest.h"
+#include <algorithm>
+#include <initializer_list>
+
+using namespace llvm;
+using namespace llvm::hlsl;
+
+namespace {
+
+class HLSLSemanticSignaturePackingTest : public testing::Test {
+protected:
+  struct ElementConfig {
+    dxbc::PSV::SemanticKind SemanticKind;
+    uint32_t Rows;
+    uint8_t Cols;
+    dxil::ElementType CompType;
+    dxbc::PSV::InterpolationMode InterpMode;
+  };
+
+  struct ExpectedLocation {
+    uint32_t Row;
+    uint8_t Col;
+  };
+
+  static constexpr ExpectedLocation Unallocated = {UnallocatedRow,
+                                                   UnallocatedCol};
+
+  struct TestConfig {
+    Triple::EnvironmentType ShaderStage;
+    IOType IOTy;
+    SmallVector<ElementConfig> Elements;
+
+    TestConfig(Triple::EnvironmentType ShaderStage, IOType IOTy,
+               std::initializer_list<ElementConfig> Elements)
+        : ShaderStage(ShaderStage), IOTy(IOTy), Elements(Elements) {}
+  };
+
+  SmallVector<SemanticSignatureElement>
+  makeSignature(const TestConfig &Config) {
+    SmallVector<SemanticSignatureElement> Elements;
+    for (const ElementConfig &Element : Config.Elements) {
+      SmallVector<uint32_t> SemanticIndices;
+      for (uint32_t Row = 0; Row != Element.Rows; ++Row)
+        SemanticIndices.push_back(Row);
+
+      Elements.emplace_back(
+          /*SigId=*/static_cast<uint32_t>(Elements.size()),
+          /*SemanticName=*/"TEST",
+          /*CompType=*/Element.CompType,
+          /*SemanticKind=*/Element.SemanticKind,
+          /*SemanticIndices=*/SemanticIndices,
+          /*Cols=*/Element.Cols);
+      Elements.back().InterpMode = Element.InterpMode;
+    }
+    return Elements;
+  }
+
+  Error packStacked(SmallVectorImpl<SemanticSignatureElement> &Elements,
+                    const TestConfig &Config) {
+    return packSignatureStacked(Elements, Config.ShaderStage, Config.IOTy);
+  }
+
+  void expectPacking(const TestConfig &Config, unsigned ExpectedRows,
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inbelic wrote:

Updated to verify so that we don't just rename it in the next (indexed) pr

https://github.com/llvm/llvm-project/pull/218060