Support link-time constants. (#3564)

* Support link-time constants.

* Fix.

* Fix.

3 files changed, 177 insertions, 1 deletions

diff --git a/tools/gfx-unit-test/gfx-test-util.h b/tools/gfx-unit-test/gfx-test-util.h
index 22b9b2fd3..501deeae0 100644
--- a/tools/gfx-unit-test/gfx-test-util.h
+++ b/tools/gfx-unit-test/gfx-test-util.h
@@ -8,7 +8,7 @@
 namespace gfx_test
 {
         /// Helper function for print out diagnostic messages output by Slang compiler.
-    void diagnoseIfNeeded(ISlangWriter* diagnosticWriter, slang::IBlob* diagnosticsBlob);
+    void diagnoseIfNeeded(slang::IBlob* diagnosticsBlob);
 
         /// Loads a compute shader module and produces a `gfx::IShaderProgram`.
     Slang::Result loadComputeProgram(
diff --git a/tools/gfx-unit-test/link-time-constant.cpp b/tools/gfx-unit-test/link-time-constant.cpp
new file mode 100644
index 000000000..62cb294c1
--- /dev/null
+++ b/tools/gfx-unit-test/link-time-constant.cpp
@@ -0,0 +1,156 @@
+#include "tools/unit-test/slang-unit-test.h"
+
+#include "slang-gfx.h"
+#include "gfx-test-util.h"
+#include "tools/gfx-util/shader-cursor.h"
+#include "source/core/slang-basic.h"
+#include "source/core/slang-blob.h"
+
+using namespace gfx;
+
+namespace gfx_test
+{
+    static Slang::Result loadProgram(
+        gfx::IDevice* device,
+        Slang::ComPtr<gfx::IShaderProgram>& outShaderProgram,
+        const char* shaderModuleName,
+        const char* entryPointName,
+        slang::ProgramLayout*& slangReflection,
+        const char* additionalModuleSource)
+    {
+        Slang::ComPtr<slang::ISession> slangSession;
+        SLANG_RETURN_ON_FAIL(device->getSlangSession(slangSession.writeRef()));
+        Slang::ComPtr<slang::IBlob> diagnosticsBlob;
+        slang::IModule* module = slangSession->loadModule(shaderModuleName, diagnosticsBlob.writeRef());
+        diagnoseIfNeeded(diagnosticsBlob);
+        if (!module)
+            return SLANG_FAIL;
+
+        auto additionalModuleBlob = Slang::UnownedRawBlob::create(additionalModuleSource, strlen(additionalModuleSource));
+        slang::IModule* additionalModule = slangSession->loadModuleFromSource("linkedConstants", "path",
+            additionalModuleBlob);
+
+        ComPtr<slang::IEntryPoint> computeEntryPoint;
+        SLANG_RETURN_ON_FAIL(
+            module->findEntryPointByName(entryPointName, computeEntryPoint.writeRef()));
+
+        Slang::List<slang::IComponentType*> componentTypes;
+        componentTypes.add(module);
+        componentTypes.add(computeEntryPoint);
+        componentTypes.add(additionalModule);
+
+        Slang::ComPtr<slang::IComponentType> composedProgram;
+        SlangResult result = slangSession->createCompositeComponentType(
+            componentTypes.getBuffer(),
+            componentTypes.getCount(),
+            composedProgram.writeRef(),
+            diagnosticsBlob.writeRef());
+        diagnoseIfNeeded(diagnosticsBlob);
+        SLANG_RETURN_ON_FAIL(result);
+
+        ComPtr<slang::IComponentType> linkedProgram;
+        result = composedProgram->link(linkedProgram.writeRef(), diagnosticsBlob.writeRef());
+        diagnoseIfNeeded(diagnosticsBlob);
+        SLANG_RETURN_ON_FAIL(result);
+
+        composedProgram = linkedProgram;
+        slangReflection = composedProgram->getLayout();
+
+        gfx::IShaderProgram::Desc programDesc = {};
+        programDesc.slangGlobalScope = composedProgram.get();
+
+        auto shaderProgram = device->createProgram(programDesc);
+
+        outShaderProgram = shaderProgram;
+        return SLANG_OK;
+    }
+
+    void linkTimeConstantTestImpl(IDevice* device, UnitTestContext* context)
+    {
+        Slang::ComPtr<ITransientResourceHeap> transientHeap;
+        ITransientResourceHeap::Desc transientHeapDesc = {};
+        transientHeapDesc.constantBufferSize = 4096;
+        GFX_CHECK_CALL_ABORT(
+            device->createTransientResourceHeap(transientHeapDesc, transientHeap.writeRef()));
+
+        ComPtr<IShaderProgram> shaderProgram;
+        slang::ProgramLayout* slangReflection;
+        GFX_CHECK_CALL_ABORT(loadProgram(device, shaderProgram, "link-time-constant", "computeMain", slangReflection, 
+            R"(
+                export static const bool turnOnFeature = true;
+                export static const float constValue = 2.0;
+            )"));
+
+        ComputePipelineStateDesc pipelineDesc = {};
+        pipelineDesc.program = shaderProgram.get();
+        ComPtr<gfx::IPipelineState> pipelineState;
+        GFX_CHECK_CALL_ABORT(
+            device->createComputePipelineState(pipelineDesc, pipelineState.writeRef()));
+
+        const int numberCount = 4;
+        float initialData[] = { 0.0f, 0.0f, 0.0f, 0.0f };
+        IBufferResource::Desc bufferDesc = {};
+        bufferDesc.sizeInBytes = numberCount * sizeof(float);
+        bufferDesc.format = gfx::Format::Unknown;
+        bufferDesc.elementSize = sizeof(float);
+        bufferDesc.allowedStates = ResourceStateSet(
+            ResourceState::ShaderResource,
+            ResourceState::UnorderedAccess,
+            ResourceState::CopyDestination,
+            ResourceState::CopySource);
+        bufferDesc.defaultState = ResourceState::UnorderedAccess;
+        bufferDesc.memoryType = MemoryType::DeviceLocal;
+
+        ComPtr<IBufferResource> numbersBuffer;
+        GFX_CHECK_CALL_ABORT(device->createBufferResource(
+            bufferDesc,
+            (void*)initialData,
+            numbersBuffer.writeRef()));
+
+        ComPtr<IResourceView> bufferView;
+        IResourceView::Desc viewDesc = {};
+        viewDesc.type = IResourceView::Type::UnorderedAccess;
+        viewDesc.format = Format::Unknown;
+        GFX_CHECK_CALL_ABORT(
+            device->createBufferView(numbersBuffer, nullptr, viewDesc, bufferView.writeRef()));
+
+        // We have done all the set up work, now it is time to start recording a command buffer for
+        // GPU execution.
+        {
+            ICommandQueue::Desc queueDesc = { ICommandQueue::QueueType::Graphics };
+            auto queue = device->createCommandQueue(queueDesc);
+
+            auto commandBuffer = transientHeap->createCommandBuffer();
+            auto encoder = commandBuffer->encodeComputeCommands();
+
+            auto rootObject = encoder->bindPipeline(pipelineState);
+
+            ShaderCursor entryPointCursor(
+                rootObject->getEntryPoint(0)); // get a cursor the the first entry-point.
+            // Bind buffer view to the entry point.
+            entryPointCursor.getPath("buffer").setResource(bufferView);
+
+            encoder->dispatchCompute(1, 1, 1);
+            encoder->endEncoding();
+            commandBuffer->close();
+            queue->executeCommandBuffer(commandBuffer);
+            queue->waitOnHost();
+        }
+
+        compareComputeResult(
+            device,
+            numbersBuffer,
+            Slang::makeArray<float>(2.0));
+    }
+
+    SLANG_UNIT_TEST(linkTimeConstantD3D12)
+    {
+        runTestImpl(linkTimeConstantTestImpl, unitTestContext, Slang::RenderApiFlag::D3D12);
+    }
+
+    SLANG_UNIT_TEST(linkTimeConstantVulkan)
+    {
+        runTestImpl(linkTimeConstantTestImpl, unitTestContext, Slang::RenderApiFlag::Vulkan);
+    }
+
+}
diff --git a/tools/gfx-unit-test/link-time-constant.slang b/tools/gfx-unit-test/link-time-constant.slang
new file mode 100644
index 000000000..385932dd4
--- /dev/null
+++ b/tools/gfx-unit-test/link-time-constant.slang
@@ -0,0 +1,20 @@
+extern static const bool turnOnFeature;
+extern static const float constValue;
+
+// Main entry-point. Write some value into buffer depending on link
+// time constant.
+[shader("compute")]
+[numthreads(4, 1, 1)]
+void computeMain(
+    uint3 sv_dispatchThreadID: SV_DispatchThreadID,
+    uniform RWStructuredBuffer<float> buffer)
+{
+    if (turnOnFeature)
+    {
+        buffer[0] = constValue;
+    }
+    else
+    {
+        buffer[0] = -1.0;
+    }
+}