[DRAFT] Ignore this - LinAlg PSV0 WIP by V-FEXrt · Pull Request #8875 · microsoft/DirectXShaderCompiler

Ashley Coleman (V-FEXrt) · 2026-09-02T19:45:51Z

No description provided.

github-actions · 2026-09-02T19:46:44Z

⚠️ C/C++ code formatter, clang-format found issues in your code. ⚠️

You can test this locally with the following command:

git-clang-format --diff 61d3e61e5f0c8106a815d4936d8877047b302a00 23419e28bf7583dad7c9f64fce38e7d50028380b -- include/dxc/DXIL/DxilConstants.h include/dxc/DXIL/DxilOperations.h include/dxc/DXIL/DxilShaderFlags.h include/dxc/DxilContainer/DxilPipelineStateValidation.h lib/DXIL/DxilOperations.cpp lib/DXIL/DxilShaderFlags.cpp lib/DxilContainer/DxilContainerAssembler.cpp lib/DxilContainer/DxilPipelineStateValidation.cpp lib/DxilValidation/DxilContainerValidation.cpp lib/HLSL/DxilPreparePasses.cpp

View the diff from clang-format here.

diff --git a/lib/DxilContainer/DxilContainerAssembler.cpp b/lib/DxilContainer/DxilContainerAssembler.cpp
index 9d1a9bb8..5c3baaac 100644
--- a/lib/DxilContainer/DxilContainerAssembler.cpp
+++ b/lib/DxilContainer/DxilContainerAssembler.cpp
@@ -931,8 +931,8 @@ private:
               auto *TargetType = dyn_cast<ConstantInt>(CI->getArgOperand(3));
               if (!TargetType)
                 break;
-              AccumulatorType = static_cast<DXIL::ComponentType>(
-                  TargetType->getZExtValue());
+              AccumulatorType =
+                  static_cast<DXIL::ComponentType>(TargetType->getZExtValue());
             }
             uint8_t Flag =
                 OpCode == DXIL::OpCode::LinAlgMatrixAccumulateToDescriptor

Check this box to apply formatting changes to this branch.

Ashley Coleman (V-FEXrt) · 2026-09-02T19:56:14Z

+  std::vector<PSVLinAlgAccumulateStore0> m_LinAlgAccumulateStores;
  unsigned EntryFunctionName = 0;

+  static bool GetLinAlgMatrixInfo(Type *Ty, LinAlgMatrixInfo &Info) {


std::optional

Ashley Coleman (V-FEXrt) · 2026-09-02T19:57:10Z

+    StringRef Mangling =
+        dxilutil::GetHLSLLinAlgMatrixTypeMangling(cast<StructType>(Ty));
+    unsigned TypeValue, UseValue, ScopeValue;
+    if (sscanf(Mangling.str().c_str(), "C%uM%uN%uU%uS%u", &TypeValue, &Info.M,


scanf is bad. Can we not use the metadata from the module?

Ashley Coleman (V-FEXrt) · 2026-09-02T19:59:45Z

+    case 16:
+      return IsSigned ? DXIL::ComponentType::I16 : DXIL::ComponentType::U16;
+    case 32:
+      return IsSigned ? DXIL::ComponentType::I32 : DXIL::ComponentType::U32;


Need to poke at the use case but this is lossy. ComponentType::F8_E4M3FN is also a 32bit width integer

Ashley Coleman (V-FEXrt) · 2026-09-02T20:09:53Z

+  }
+
+  uint32_t AddShapeIndexArray(ArrayRef<uint32_t> ShapeIndexes) {
+    for (uint32_t Offset = 0;


this seems to be checking if its already been added before. Is that actually necessary?

Ashley Coleman (V-FEXrt) · 2026-09-02T20:11:16Z

+    return Offset;
+  }
+
+  static void AddUniqueIndex(std::vector<uint32_t> &Indexes, uint32_t Index) {


Ashley Coleman (V-FEXrt) · 2026-09-02T20:24:05Z

+        continue;
+      if (CallInst *CI = dyn_cast<CallInst>(V)) {
+        DXIL::OpCode OpCode = OP::getOpCode(CI);
+        if (OpCode == DXIL::OpCode::LinAlgMatrixLoadFromDescriptor) {


switch statements

Use the generated DXIL types here

Ashley Coleman (V-FEXrt) · 2026-09-02T20:28:09Z

+    auto CollectConstruction = [&](Type *Ty) {
+      LinAlgMatrixInfo Matrix;
+      if (!GetLinAlgMatrixInfo(Ty, Matrix) ||
+          Matrix.Scope == DXIL::MatrixScope::Thread)


The || here is because of

Thread-scope matrices are excluded from MatrixConstruction gathering, because runtime feature info query is defined only for wave/group scope matrices.

it should be its only arm with a comment

Ashley Coleman (V-FEXrt) · 2026-09-02T20:30:36Z

+      if (!GetLinAlgMatrixInfo(Ty, Matrix) ||
+          Matrix.Scope == DXIL::MatrixScope::Thread)
+        return;
+      uint32_t M = Matrix.Use == DXIL::MatrixUse::B ? 0 : Matrix.M;


its probably clearer to just switch over the use here instead of having so many ternary's

Ashley Coleman (V-FEXrt) · 2026-09-02T20:32:26Z

+          switch (OpCode) {
+          case DXIL::OpCode::LinAlgMatVecMul:
+          case DXIL::OpCode::LinAlgMatVecMulAdd: {
+            LinAlgMatrixInfo Matrix;


Generated DXIL type

Ashley Coleman (V-FEXrt) · 2026-09-02T20:33:01Z

+            if (!GetLinAlgMatrixInfo(CI->getArgOperand(1)->getType(), Matrix))
+              break;
+            bool IsSigned =
+                cast<ConstantInt>(CI->getArgOperand(2))->getZExtValue() != 0;


all the casts need to be confirmed as allowed

Ashley Coleman (V-FEXrt) · 2026-09-02T20:36:06Z

+            DXIL::ComponentType InputType = static_cast<DXIL::ComponentType>(
+                cast<ConstantInt>(CI->getArgOperand(4))->getZExtValue());
+            uint8_t Flags = GetMatVecLayoutFlags(CI->getArgOperand(1));
+            auto It = std::find_if(


another slightly different spelling of the "add or create" shape

Ashley Coleman (V-FEXrt) · 2026-09-02T20:36:35Z

+          case DXIL::OpCode::LinAlgMatrixMultiply:
+          case DXIL::OpCode::LinAlgMatrixMultiplyAccumulate: {
+            LinAlgMatrixInfo Result, A, B;
+            if (!GetLinAlgMatrixInfo(CI->getType(), Result) ||


Generated DXIL type

Ashley Coleman (V-FEXrt) added 2 commits September 2, 2026 10:53

save work

c3286da

fix tests

23419e2

github-project-automation Bot added this to HLSL Roadmap Sep 2, 2026

github-project-automation Bot moved this to New in HLSL Roadmap Sep 2, 2026