Fix ImmutableSamplers2 test when no resources provided in PRS Desc.

Author: hzqst

Graphics/GraphicsEngineVulkan/src/DeviceContextVkImpl.cpp

@@ -647,7 +647,16 @@ void DeviceContextVkImpl::CommitShaderResources(IShaderResourceBinding* pShaderR
 
     const Uint32                           SRBIndex   = pResBindingVkImpl->GetBindingIndex();
     const PipelineResourceSignatureVkImpl* pSignature = pResBindingVkImpl->GetSignature();
-    ResourceBindInfo&                      BindInfo   = GetBindInfo(pResBindingVkImpl->GetPipelineType());
+
+    // Use PSO's pipeline type as fallback when PRS has no resources and thus PIPELINE_TYPE_INVALID
+    PIPELINE_TYPE SrbPipelineType = pResBindingVkImpl->GetPipelineType();
+    if (SrbPipelineType == PIPELINE_TYPE_INVALID)
+    {
+        VERIFY_EXPR(m_pPipelineState != nullptr);
+        SrbPipelineType = m_pPipelineState->GetDesc().PipelineType;
+    }
+
+    ResourceBindInfo&                      BindInfo   = GetBindInfo(SrbPipelineType);
     ResourceBindInfo::DescriptorSetInfo&   SetInfo    = BindInfo.SetInfo[SRBIndex];
 
     // Always bind the SRB, even if it has no descriptor sets (e.g., only push constants)

Tests/DiligentCoreAPITest/src/PipelineResourceSignatureTest.cpp

@@ -771,14 +771,6 @@ TEST_F(PipelineResourceSignatureTest, ImmutableSamplers2)
         PipelineResourceSignatureDesc Desc;
         Desc.Name         = "ImmutableSamplers2 - PRS3";
         Desc.BindingIndex = 3;
-
-        //Note that PipelineTypeFromShaderStages() will return PIPELINE_TYPE_INVALID if we leave Desc.Resources empty,
-        //which will lead to PIPELINE_TYPE_INVALID from CmmoitShaderResources() -> pResBindingVkImpl->GetPipelineType()
-        //and causing assert or crash essentially.
-        const PipelineResourceDesc PlaceholderResource[] = {
-            {SHADER_TYPE_VERTEX, "Placeholder", 1, SHADER_RESOURCE_TYPE_CONSTANT_BUFFER, SHADER_RESOURCE_VARIABLE_TYPE_STATIC}};
-        Desc.Resources    = PlaceholderResource;
-        Desc.NumResources = _countof(PlaceholderResource);
         pDevice->CreatePipelineResourceSignature(Desc, &pSignature3);
         ASSERT_NE(pSignature3, nullptr);
     }