Fix incorrect binding index assignment for StructuredBuffer and ByteAddressBuffer with DescriptorHandle (#8252)

- [x] Fix segmentation fault in wrapConstantBufferElement for
DescriptorHandle types
- [x] Split DescriptorKind.Buffer into ConstantBuffer and StorageBuffer
- [x] Update binding enums with descriptive names (ConstantBuffer_Read,
StorageBuffer_Read, etc.)
- [x] Update resource type mappings for correct binding assignments
- [x] Update template logic to handle ConstantBuffer and StorageBuffer
kinds separately
- [x] Update tests to reflect correct binding assignments
- [x] Split DescriptorKind.TexelBuffer into UniformTexelBuffer and
StorageTexelBuffer
- [x] Update TextureBuffer<T> to use UniformTexelBuffer kind
- [x] Update _Texture extension to determine texel buffer kind based on
access mode
- [x] Update test desc-handle-1.slang to handle new DescriptorKind enum
cases

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---------

Co-authored-by: Yong He <yonghe@outlook.com>

2 files changed, 54 insertions, 47 deletions

diff --git a/source/slang/hlsl.meta.slang b/source/slang/hlsl.meta.slang
index bf5039905..489bcbab6 100644
--- a/source/slang/hlsl.meta.slang
+++ b/source/slang/hlsl.meta.slang
@@ -22770,10 +22770,13 @@ enum DescriptorKind
     Unknown, /// Unknown descriptor kind.
     Texture, /// A texture descriptor.
     CombinedTextureSampler, /// A combined texture and sampler state descriptor.
-    Buffer, /// A buffer descriptor.
+    ConstantBuffer, /// A constant buffer descriptor.
+    StorageBuffer, /// A storage buffer descriptor.
+    Buffer = StorageBuffer, /// Deprecated. Use `StorageBuffer` instead.
     Sampler, /// A sampler state descriptor.
     AccelerationStructure, /// A ray tracing acceleration structure descriptor.
-    TexelBuffer /// A texel buffer descriptor.
+    UniformTexelBuffer, /// A uniform texel buffer descriptor (read-only).
+    StorageTexelBuffer /// A storage texel buffer descriptor (read-write).
 }
 
 enum DescriptorAccess
@@ -22827,7 +22830,7 @@ extension _Texture<T, Shape, isArray, isMS, sampleCount, access, isShadow, isCom
     typealias Handle = DescriptorHandle<This>;
 
     static const DescriptorKind kind = (Shape.flavor == __ShapeBuffer.flavor ?
-        DescriptorKind.TexelBuffer : (isCombined != 0 ? DescriptorKind.CombinedTextureSampler : DescriptorKind.Texture)
+        (access == $(kCoreModule_ResourceAccessReadOnly) ? DescriptorKind.UniformTexelBuffer : DescriptorKind.StorageTexelBuffer) : (isCombined != 0 ? DescriptorKind.CombinedTextureSampler : DescriptorKind.Texture)
 );
     static const DescriptorAccess descriptorAccess = (DescriptorAccess)access;
 
@@ -22849,19 +22852,19 @@ struct DynamicResourceTypeInfo
 };
 
 const DynamicResourceTypeInfo kDynamicResourceCastableTypes[] = {
-    { "StructuredBuffer<T, L>", "Buffer", "General", "Read" },
-    { "RWStructuredBuffer<T, L>", "Buffer", "General", "ReadWrite" },
-    { "AppendStructuredBuffer<T, L>", "Buffer", "General", "ReadWrite" },
-    { "ConsumeStructuredBuffer<T, L>", "Buffer", "General", "ReadWrite" },
-    { "RasterizerOrderedStructuredBuffer<T, L>", "Buffer", "General", "ReadWrite" },
-    { "ByteAddressBuffer", "Buffer", "General", "Read" },
-    { "RWByteAddressBuffer", "Buffer", "General", "ReadWrite" },
-    { "RasterizerOrderedByteAddressBuffer", "Buffer", "General", "ReadWrite" },
+    { "StructuredBuffer<T, L>", "StorageBuffer", "General", "Read" },
+    { "RWStructuredBuffer<T, L>", "StorageBuffer", "General", "ReadWrite" },
+    { "AppendStructuredBuffer<T, L>", "StorageBuffer", "General", "ReadWrite" },
+    { "ConsumeStructuredBuffer<T, L>", "StorageBuffer", "General", "ReadWrite" },
+    { "RasterizerOrderedStructuredBuffer<T, L>", "StorageBuffer", "General", "ReadWrite" },
+    { "ByteAddressBuffer", "StorageBuffer", "General", "Read" },
+    { "RWByteAddressBuffer", "StorageBuffer", "General", "ReadWrite" },
+    { "RasterizerOrderedByteAddressBuffer", "StorageBuffer", "General", "ReadWrite" },
     { "SamplerState", "Sampler", "Sampler", "Unknown" },
     { "SamplerComparisonState", "Sampler", "Sampler", "Unknown" },
-    { "ConstantBuffer<T, L>", "Buffer", "General", "Read"},
-    { "TextureBuffer<T>", "Buffer", "General", "Read"},
-    { "RaytracingAccelerationStructure", "AccelerationStructure", "General", "Read"},
+    { "ConstantBuffer<T, L>", "ConstantBuffer", "General", "Read" },
+    { "TextureBuffer<T>", "UniformTexelBuffer", "General", "Read" },
+    { "RaytracingAccelerationStructure", "AccelerationStructure", "General", "Read" },
 };
 
 for (auto type : kDynamicResourceCastableTypes) {
@@ -22996,12 +22999,13 @@ enum DefaultVkBindlessBindings : uint
 {
     Sampler = 0, /// SAMPLER
     CombinedTextureSampler = 1, /// COMBINED_IMAGE_SAMPLER
-    Texture_Read = 2, /// SAMPLED_IMAGE
-    Texture_ReadWrite = 3, /// STORAGE_IMAGE
-    TexelBuffer_Read = 4, /// UNIFORM_TEXEL_BUFFER
-    TexelBuffer_ReadWrite = 5, /// STORAGE_TEXEL_BUFFER
-    Buffer_Read = 6, /// UNIFORM_BUFFER
-    Buffer_ReadWrite = 7, /// STORAGE_BUFFER
+    SampledImage = 2, /// SAMPLED_IMAGE
+    StorageImage = 3, /// STORAGE_IMAGE
+    UniformTexelBuffer = 4, /// UNIFORM_TEXEL_BUFFER
+    StorageTexelBuffer = 5, /// STORAGE_TEXEL_BUFFER
+    ConstantBuffer_Read = 6, /// UNIFORM_BUFFER
+    StorageBuffer_Read = 7, /// STORAGE_BUFFER
+    StorageBuffer_ReadWrite = 7, /// STORAGE_BUFFER
     Unknown = 8, /// Other
 }
 
@@ -23010,12 +23014,13 @@ enum VkMutableBindlessBindings : uint
 {
     Sampler = 0, /// SAMPLER
     CombinedTextureSampler = 1, /// COMBINED_IMAGE_SAMPLER
-    Texture_Read = 2, /// SAMPLED_IMAGE
-    Texture_ReadWrite = 2, /// STORAGE_IMAGE
-    TexelBuffer_Read = 2, /// UNIFORM_TEXEL_BUFFER
-    TexelBuffer_ReadWrite = 2, /// STORAGE_TEXEL_BUFFER
-    Buffer_Read = 2, /// UNIFORM_BUFFER
-    Buffer_ReadWrite = 2, /// STORAGE_BUFFER,
+    SampledImage = 2, /// SAMPLED_IMAGE
+    StorageImage = 2, /// STORAGE_IMAGE
+    UniformTexelBuffer = 2, /// UNIFORM_TEXEL_BUFFER
+    StorageTexelBuffer = 2, /// STORAGE_TEXEL_BUFFER
+    ConstantBuffer_Read = 2, /// UNIFORM_BUFFER
+    StorageBuffer_Read = 2, /// STORAGE_BUFFER
+    StorageBuffer_ReadWrite = 2, /// STORAGE_BUFFER,
     Unknown = 3, /// Other
 }
 
@@ -23096,23 +23101,28 @@ ${{{{
     case DescriptorKind.Texture:
     {
         if(DescriptorAccess.Read == T.descriptorAccess)
-            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).Texture_Read)[((uint2)handleValue).x];
+            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).SampledImage)[((uint2)handleValue).x];
         else
-            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).Texture_ReadWrite)[((uint2)handleValue).x];
+            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).StorageImage)[((uint2)handleValue).x];
     }
-    case DescriptorKind.TexelBuffer:
+    case DescriptorKind.UniformTexelBuffer:
     {
-        if(DescriptorAccess.Read == T.descriptorAccess)
-            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).TexelBuffer_Read)[((uint2)handleValue).x];
-        else
-            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).TexelBuffer_ReadWrite)[((uint2)handleValue).x];
+        return __getDynamicResourceHeap<T>($(bindlessOption.enumType).UniformTexelBuffer)[((uint2)handleValue).x];
+    }
+    case DescriptorKind.StorageTexelBuffer:
+    {
+        return __getDynamicResourceHeap<T>($(bindlessOption.enumType).StorageTexelBuffer)[((uint2)handleValue).x];
+    }
+    case DescriptorKind.ConstantBuffer:
+    {
+        return __getDynamicResourceHeap<T>($(bindlessOption.enumType).ConstantBuffer_Read)[((uint2)handleValue).x];
     }
-    case DescriptorKind.Buffer:
+    case DescriptorKind.StorageBuffer:
     {
         if(DescriptorAccess.Read == T.descriptorAccess)
-            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).Buffer_Read)[((uint2)handleValue).x];
+            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).StorageBuffer_Read)[((uint2)handleValue).x];
         else
-            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).Buffer_ReadWrite)[((uint2)handleValue).x];
+            return __getDynamicResourceHeap<T>($(bindlessOption.enumType).StorageBuffer_ReadWrite)[((uint2)handleValue).x];
     }
     case DescriptorKind.AccelerationStructure:
         return __slang_noop_cast<T>(RaytracingAccelerationStructure(__asuint64((uint2)handleValue)));
diff --git a/source/slang/slang-check-decl.cpp b/source/slang/slang-check-decl.cpp
index 77a799f1c..6f2b01aa1 100644
--- a/source/slang/slang-check-decl.cpp
+++ b/source/slang/slang-check-decl.cpp
@@ -8992,6 +8992,7 @@ void SemanticsDeclBodyVisitor::visitEnumDecl(EnumDecl* decl)
                 tryConstantFoldExpr(explicitTagValExpr, ConstantFoldingKind::CompileTime, nullptr);
             if (explicitTagVal)
             {
+                caseDecl->tagVal = explicitTagVal;
                 if (auto constIntVal = as<ConstantIntVal>(explicitTagVal))
                 {
                     defaultTag = constIntVal->getValue();
@@ -9005,8 +9006,10 @@ void SemanticsDeclBodyVisitor::visitEnumDecl(EnumDecl* decl)
             else
             {
                 // If this happens, then the explicit tag value expression
-                // doesn't seem to be a constant after all. In this case
-                // we expect the checking logic to have applied already.
+                // doesn't seem to be a constant after all.
+                getSink()->diagnose(
+                    explicitTagValExpr,
+                    Diagnostics::expectedIntegerConstantNotConstant);
             }
         }
         else
@@ -9017,8 +9020,8 @@ void SemanticsDeclBodyVisitor::visitEnumDecl(EnumDecl* decl)
             tagValExpr->loc = caseDecl->loc;
             tagValExpr->type = QualType(tagType);
             tagValExpr->value = defaultTag;
-
             caseDecl->tagExpr = tagValExpr;
+            caseDecl->tagVal = m_astBuilder->getIntVal(enumType, defaultTag);
         }
 
         // Default tag for the next case will be one more than
@@ -9058,15 +9061,9 @@ void SemanticsDeclBodyVisitor::visitEnumCaseDecl(EnumCaseDecl* decl)
     if (auto initExpr = decl->tagExpr)
     {
         initExpr = CheckTerm(initExpr);
-        initExpr = coerce(CoercionSite::General, tagType, initExpr, getSink());
 
-        // We want to enforce that this is an integer constant
-        // expression.
-        decl->tagVal = CheckIntegerConstantExpression(
-            initExpr,
-            IntegerConstantExpressionCoercionType::AnyInteger,
-            nullptr,
-            ConstantFoldingKind::CompileTime);
+        if (initExpr->type != decl->type.type)
+            initExpr = coerce(CoercionSite::General, tagType, initExpr, getSink());
 
         decl->tagExpr = initExpr;
     }