Introduce CDataLayout & -fvk-use-c-layout (#8136)

Closes #8112. ~~The issue asks for a "C layout", but in this PR I use
the term "CPU layout" because this naming was pre-existing in the
codebase as `kCPULayoutRulesImpl_`. The primary purpose of this layout
is to match CPU-side struct definitions with the shader side. I'm open
to better naming suggestions, though.~~

Edit: switched back to using `CDataLayout` & `-fvk-use-c-layout`, as the
CPU target depends on the object layout rules of existing CPU layout
rules, but they're incompatible with actual shaders. So a new
`kCLayoutRulesImpl_` was needed anyway.

---------

Co-authored-by: Ellie Hermaszewska <ellieh@nvidia.com>

1 files changed, 163 insertions, 0 deletions

diff --git a/source/slang/slang-type-layout.cpp b/source/slang/slang-type-layout.cpp
index 275a178d0..3e2560755 100644
--- a/source/slang/slang-type-layout.cpp
+++ b/source/slang/slang-type-layout.cpp
@@ -1090,6 +1090,29 @@ struct CPULayoutRulesFamilyImpl : LayoutRulesFamilyImpl
     LayoutRulesImpl* getStructuredBufferRules(CompilerOptionSet& compilerOptions) override;
 };
 
+struct CLayoutRulesFamilyImpl : LayoutRulesFamilyImpl
+{
+    virtual LayoutRulesImpl* getAnyValueRules() override;
+    virtual LayoutRulesImpl* getConstantBufferRules(
+        CompilerOptionSet& compilerOptions,
+        Type* containerType) override;
+    virtual LayoutRulesImpl* getPushConstantBufferRules() override;
+    virtual LayoutRulesImpl* getTextureBufferRules(CompilerOptionSet& compilerOptions) override;
+    virtual LayoutRulesImpl* getVaryingInputRules() override;
+    virtual LayoutRulesImpl* getVaryingOutputRules() override;
+    virtual LayoutRulesImpl* getSpecializationConstantRules() override;
+    virtual LayoutRulesImpl* getShaderStorageBufferRules(
+        CompilerOptionSet& compilerOptions) override;
+    virtual LayoutRulesImpl* getParameterBlockRules(CompilerOptionSet& compilerOptions) override;
+
+    LayoutRulesImpl* getRayPayloadParameterRules() override;
+    LayoutRulesImpl* getCallablePayloadParameterRules() override;
+    LayoutRulesImpl* getHitAttributesParameterRules() override;
+
+    LayoutRulesImpl* getShaderRecordConstantBufferRules() override;
+    LayoutRulesImpl* getStructuredBufferRules(CompilerOptionSet& compilerOptions) override;
+};
+
 struct CUDALayoutRulesFamilyImpl : LayoutRulesFamilyImpl
 {
     virtual LayoutRulesImpl* getAnyValueRules() override;
@@ -1170,6 +1193,7 @@ struct WGSLLayoutRulesFamilyImpl : LayoutRulesFamilyImpl
 GLSLLayoutRulesFamilyImpl kGLSLLayoutRulesFamilyImpl;
 HLSLLayoutRulesFamilyImpl kHLSLLayoutRulesFamilyImpl;
 CPULayoutRulesFamilyImpl kCPULayoutRulesFamilyImpl;
+CLayoutRulesFamilyImpl kCLayoutRulesFamilyImpl;
 CUDALayoutRulesFamilyImpl kCUDALayoutRulesFamilyImpl;
 MetalLayoutRulesFamilyImpl kMetalLayoutRulesFamilyImpl;
 MetalArgumentBufferTier2LayoutRulesFamilyImpl kMetalArgumentBufferTier2LayoutRulesFamilyImpl;
@@ -1341,6 +1365,69 @@ LayoutRulesImpl kCPUAnyValueLayoutRulesImpl_ = {
     &kCPUObjectLayoutRulesImpl,
 };
 
+// C layout
+
+LayoutRulesImpl kCLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kCPULayoutRulesImpl,
+    &kGLSLObjectLayoutRulesImpl,
+};
+
+LayoutRulesImpl kCAnyValueLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kDefaultLayoutRulesImpl,
+    &kCPUObjectLayoutRulesImpl,
+};
+
+LayoutRulesImpl kCPushConstantRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kCPULayoutRulesImpl,
+    &kGLSLPushConstantBufferObjectLayoutRulesImpl_,
+};
+
+LayoutRulesImpl kCVaryingInputLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kGLSLVaryingOutputLayoutRulesImpl,
+    &kGLSLObjectLayoutRulesImpl,
+};
+
+LayoutRulesImpl kCVaryingOutputLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kGLSLVaryingOutputLayoutRulesImpl,
+    &kGLSLObjectLayoutRulesImpl,
+};
+
+LayoutRulesImpl kCSpecializationConstantLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kGLSLSpecializationConstantLayoutRulesImpl,
+    &kGLSLObjectLayoutRulesImpl,
+};
+
+LayoutRulesImpl kCShaderRecordLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kCPULayoutRulesImpl,
+    &kGLSLShaderRecordConstantBufferObjectLayoutRulesImpl_,
+};
+
+LayoutRulesImpl kCRayPayloadParameterLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kGLSLRayPayloadParameterLayoutRulesImpl,
+    &kGLSLObjectLayoutRulesImpl,
+};
+
+LayoutRulesImpl kCCallablePayloadParameterLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kGLSLCallablePayloadParameterLayoutRulesImpl,
+    &kGLSLObjectLayoutRulesImpl,
+};
+
+LayoutRulesImpl kCHitAttributesParameterLayoutRulesImpl_ = {
+    &kCLayoutRulesFamilyImpl,
+    &kGLSLHitAttributesParameterLayoutRulesImpl,
+    &kGLSLObjectLayoutRulesImpl,
+};
+
+
 // CUDA
 
 static CUDAObjectLayoutRulesImpl kCUDAObjectLayoutRulesImpl;
@@ -1534,6 +1621,8 @@ LayoutRulesImpl* GLSLLayoutRulesFamilyImpl::getConstantBufferRules(
 {
     if (compilerOptions.shouldUseScalarLayout())
         return &kScalarLayoutRulesImpl_;
+    else if (compilerOptions.shouldUseCLayout())
+        return &kCLayoutRulesImpl_;
     else if (compilerOptions.shouldUseDXLayout())
         return &kFXCConstantBufferLayoutRulesFamilyImpl;
     if (auto cbufferType = as<ConstantBufferType>(containerType))
@@ -1548,6 +1637,8 @@ LayoutRulesImpl* GLSLLayoutRulesFamilyImpl::getConstantBufferRules(
             return &kStd430LayoutRulesImpl_;
         case ASTNodeType::ScalarDataLayoutType:
             return &kScalarLayoutRulesImpl_;
+        case ASTNodeType::CDataLayoutType:
+            return &kCLayoutRulesImpl_;
         default:
             break;
         }
@@ -1560,6 +1651,8 @@ LayoutRulesImpl* GLSLLayoutRulesFamilyImpl::getParameterBlockRules(
 {
     if (compilerOptions.shouldUseScalarLayout())
         return &kScalarLayoutRulesImpl_;
+    else if (compilerOptions.shouldUseCLayout())
+        return &kCLayoutRulesImpl_;
     else if (compilerOptions.shouldUseDXLayout())
         return &kFXCConstantBufferLayoutRulesFamilyImpl;
 
@@ -1581,6 +1674,8 @@ LayoutRulesImpl* GLSLLayoutRulesFamilyImpl::getTextureBufferRules(
 {
     if (compilerOptions.shouldUseScalarLayout())
         return &kScalarLayoutRulesImpl_;
+    else if (compilerOptions.shouldUseCLayout())
+        return &kCLayoutRulesImpl_;
     else if (compilerOptions.shouldUseDXLayout())
         return &kFXCConstantBufferLayoutRulesFamilyImpl;
 
@@ -1607,6 +1702,8 @@ LayoutRulesImpl* GLSLLayoutRulesFamilyImpl::getShaderStorageBufferRules(
 {
     if (compilerOptions.shouldUseScalarLayout())
         return &kScalarLayoutRulesImpl_;
+    else if (compilerOptions.shouldUseCLayout())
+        return &kCLayoutRulesImpl_;
     else if (compilerOptions.shouldUseDXLayout())
         return &kFXCShaderResourceLayoutRulesFamilyImpl;
 
@@ -1633,6 +1730,8 @@ LayoutRulesImpl* GLSLLayoutRulesFamilyImpl::getStructuredBufferRules(
 {
     if (compilerOptions.shouldUseScalarLayout())
         return &kScalarLayoutRulesImpl_;
+    else if (compilerOptions.shouldUseCLayout())
+        return &kCLayoutRulesImpl_;
     else if (compilerOptions.shouldUseDXLayout())
         return &kFXCShaderResourceLayoutRulesFamilyImpl;
 
@@ -1779,6 +1878,70 @@ LayoutRulesImpl* CPULayoutRulesFamilyImpl::getStructuredBufferRules(CompilerOpti
     return &kCPULayoutRulesImpl_;
 }
 
+// C compatible layout family
+
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getAnyValueRules()
+{
+    return &kCAnyValueLayoutRulesImpl_;
+}
+
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getConstantBufferRules(CompilerOptionSet&, Type*)
+{
+    return &kCLayoutRulesImpl_;
+}
+
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getPushConstantBufferRules()
+{
+    return &kCPushConstantRulesImpl_;
+}
+
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getTextureBufferRules(CompilerOptionSet&)
+{
+    return &kCLayoutRulesImpl_;
+}
+
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getVaryingInputRules()
+{
+    return &kCVaryingInputLayoutRulesImpl_;
+}
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getVaryingOutputRules()
+{
+    return &kCVaryingOutputLayoutRulesImpl_;
+}
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getSpecializationConstantRules()
+{
+    return &kCSpecializationConstantLayoutRulesImpl_;
+}
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getShaderStorageBufferRules(CompilerOptionSet&)
+{
+    return &kCLayoutRulesImpl_;
+}
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getParameterBlockRules(CompilerOptionSet&)
+{
+    return &kCLayoutRulesImpl_;
+}
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getRayPayloadParameterRules()
+{
+    return &kCRayPayloadParameterLayoutRulesImpl_;
+}
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getCallablePayloadParameterRules()
+{
+    return &kCCallablePayloadParameterLayoutRulesImpl_;
+}
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getHitAttributesParameterRules()
+{
+    return &kCHitAttributesParameterLayoutRulesImpl_;
+}
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getShaderRecordConstantBufferRules()
+{
+    return &kCShaderRecordLayoutRulesImpl_;
+}
+
+LayoutRulesImpl* CLayoutRulesFamilyImpl::getStructuredBufferRules(CompilerOptionSet&)
+{
+    return &kCLayoutRulesImpl_;
+}
+
 // CUDA Family
 
 LayoutRulesImpl* CUDALayoutRulesFamilyImpl::getAnyValueRules()