From 33e8bfd43f66613f6f834fb0e1816ef43071f2e4 Mon Sep 17 00:00:00 2001
From: Yong He <yonghe@outlook.com>
Date: Thu, 5 Sep 2024 11:53:56 -0700
Subject: [PATCH] Fix SPIRV SV_TessFactor type adaptation logic. (#5010)

* Fix SPIRV SV_TessFactor type adaptation logic.

* Fix compile error.
---
 source/slang/slang-ir-glsl-legalize.cpp | 26 +++++++++++--
 tests/bugs/gh-4456.slang                | 52 +++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 4 deletions(-)
 create mode 100644 tests/bugs/gh-4456.slang

diff --git a/source/slang/slang-ir-glsl-legalize.cpp b/source/slang/slang-ir-glsl-legalize.cpp
index dabf0294f3..d8c1aa91ef 100644
--- a/source/slang/slang-ir-glsl-legalize.cpp
+++ b/source/slang/slang-ir-glsl-legalize.cpp
@@ -1197,13 +1197,15 @@ ScalarizedVal createSimpleGLSLGlobalVarying(
 
     IRType* type = inType;
     IRType* peeledRequiredType = nullptr;
-
+    ShortList<IRInst*> peeledRequiredArraySizes;
+    bool peeledRequiredArrayLevelMatchesUserDeclaredType = false;
     // A system-value semantic might end up needing to override the type
     // that the user specified.
     if( systemValueInfo && systemValueInfo->requiredType )
     {
         type = systemValueInfo->requiredType;
         peeledRequiredType = type;
+        peeledRequiredArrayLevelMatchesUserDeclaredType = true;
         // Unpeel `type` using declarators so that it matches `inType`.
         for (auto dd = declarator; dd; dd = dd->next)
         {
@@ -1214,8 +1216,13 @@ ScalarizedVal createSimpleGLSLGlobalVarying(
                     if (auto arrayType = as<IRArrayTypeBase>(type))
                     {
                         type = arrayType->getElementType();
+                        peeledRequiredArraySizes.add(arrayType->getElementCount());
                         peeledRequiredType = type;
                     }
+                    else
+                    {
+                        peeledRequiredArrayLevelMatchesUserDeclaredType = false;
+                    }
                     break;
                 }
             }
@@ -1305,15 +1312,20 @@ ScalarizedVal createSimpleGLSLGlobalVarying(
     // Construct the actual type and type-layout for the global variable
     //
     IRTypeLayout* typeLayout = inTypeLayout;
+    Index requiredArraySizeIndex = peeledRequiredArraySizes.getCount() - 1;
     for( auto dd = declarator; dd; dd = dd->next )
     {
         switch(dd->flavor)
         {
         case GlobalVaryingDeclarator::Flavor::array:
         {
+            auto elementCount = peeledRequiredArrayLevelMatchesUserDeclaredType
+                ? peeledRequiredArraySizes[requiredArraySizeIndex] : dd->elementCount;
+
             auto arrayType = builder->getArrayType(
                 type,
-                dd->elementCount);
+                elementCount);
+            requiredArraySizeIndex--;
 
             IRArrayTypeLayout::Builder arrayTypeLayoutBuilder(builder, typeLayout);
             if( auto resInfo = inTypeLayout->findSizeAttr(kind) )
@@ -1321,10 +1333,9 @@ ScalarizedVal createSimpleGLSLGlobalVarying(
                 // TODO: it is kind of gross to be re-running some
                 // of the type layout logic here.
 
-                UInt elementCount = (UInt) getIntVal(dd->elementCount);
                 arrayTypeLayoutBuilder.addResourceUsage(
                     kind,
-                    resInfo->getSize() * elementCount);
+                    resInfo->getSize() * getIntVal(elementCount));
             }
             auto arrayTypeLayout = arrayTypeLayoutBuilder.build();
 
@@ -1774,6 +1785,13 @@ ScalarizedVal adaptType(
             val = builder->emitSwizzle(fromVector->getElementType(), val, 1, &index);
         }
     }
+    else if (auto fromArray = as<IRArrayTypeBase>(fromType))
+    {
+        if (as<IRBasicType>(toType))
+        {
+            val = builder->emitElementExtract(fromArray->getElementType(), val, builder->getIntValue(builder->getIntType(), 0));
+        }
+    }
     // TODO: actually consider what needs to go on here...
     return ScalarizedVal::value(builder->emitCast(
         toType,
diff --git a/tests/bugs/gh-4456.slang b/tests/bugs/gh-4456.slang
new file mode 100644
index 0000000000..05b346e77c
--- /dev/null
+++ b/tests/bugs/gh-4456.slang
@@ -0,0 +1,52 @@
+//TEST:SIMPLE(filecheck=CHECK): -target spirv -lang slang -D__spirv__ -emit-spirv-directly -profile ds_6_5 -entry main
+
+// CHECK: OpEntryPoint
+
+struct VSSceneIn {
+  float3 pos : POSITION;
+};
+
+struct PSSceneIn {
+  float4 pos : SV_Position;
+};
+
+struct HSPerVertexData {
+  PSSceneIn v;
+};
+
+struct HSPerPatchData {
+  float edges[3] : SV_TessFactor;
+  float inside : SV_InsideTessFactor;
+};
+
+RaytracingAccelerationStructure AccelerationStructure : register(t0);
+RayDesc MakeRayDesc()
+{
+    RayDesc desc;
+    desc.Origin = float3(0,0,0);
+    desc.Direction = float3(1,0,0);
+    desc.TMin = 0.0f;
+    desc.TMax = 9999.0;
+    return desc;
+}
+void doInitialize(out RayQuery<RAY_FLAG_FORCE_OPAQUE> query, RayDesc ray)
+{
+    query.TraceRayInline(AccelerationStructure,RAY_FLAG_FORCE_NON_OPAQUE,0xFF,ray);
+}
+
+[domain("tri")] PSSceneIn main(
+    const float3 bary : SV_DomainLocation,
+    const OutputPatch<HSPerVertexData, 3> patch,
+    const HSPerPatchData perPatchData) 
+{
+    PSSceneIn v;
+    v.pos = patch[0].v.pos * bary.x + patch[1].v.pos * bary.y + patch[2].v.pos * bary.z + perPatchData.edges[1];
+
+    RayQuery<RAY_FLAG_FORCE_OPAQUE> q;
+    RayDesc ray = MakeRayDesc();
+
+    q.TraceRayInline(AccelerationStructure,RAY_FLAG_FORCE_OPAQUE, 0xFF, ray);
+    doInitialize(q, ray);
+
+ 	return v;
+}