3 files changed, 56 insertions, 6 deletions

diff --git a/src/gui/rhi/qrhi.cpp b/src/gui/rhi/qrhi.cpp
index c82faf2566..7ebac6d1bd 100644
--- a/src/gui/rhi/qrhi.cpp
+++ b/src/gui/rhi/qrhi.cpp
@@ -3463,7 +3463,8 @@ QDebug operator<<(QDebug dbg, const QRhiShaderResourceBindings &srb)
 /*!
     \enum QRhiGraphicsPipeline::Flag
 
-    Flag values for describing the dynamic state of the pipeline. The viewport is always dynamic.
+    Flag values for describing the dynamic state of the pipeline, and other
+    options. The viewport is always dynamic.
 
     \value UsesBlendConstants Indicates that a blend color constant will be set
     via QRhiCommandBuffer::setBlendConstants()
@@ -3473,6 +3474,22 @@ QDebug operator<<(QDebug dbg, const QRhiShaderResourceBindings &srb)
 
     \value UsesScissor Indicates that a scissor rectangle will be set via
     QRhiCommandBuffer::setScissor()
+
+    \value CompileShadersWithDebugInfo Requests compiling shaders with debug
+    information enabled. This is relevant only when runtime shader compilation
+    from source code is involved, and only when the underlying infrastructure
+    supports this. With concrete examples, this is not relevant with Vulkan and
+    SPIR-V, because the GLSL-to-SPIR-V compilation does not happen at run
+    time. On the other hand, consider Direct3D and HLSL, where there are
+    multiple options: when the QShader packages ship with pre-compiled bytecode
+    (\c DXBC), debug information is to be requested through the tool that
+    generates the \c{.qsb} file, similarly to the case of Vulkan and
+    SPIR-V. However, when having HLSL source code in the pre- or
+    runtime-generated QShader packages, the first phase of compilation (HLSL
+    source to intermediate format) happens at run time too, with this flag taken
+    into account. Debug information is relevant in particular with tools like
+    RenderDoc since it allows seeing the original source code when investigating
+    the pipeline and when performing vertex or fragment shader debugging.
  */
 
 /*!
@@ -3963,6 +3980,16 @@ QRhiResource::Type QRhiSwapChain::resourceType() const
  */
 
 /*!
+    \enum QRhiComputePipeline::Flag
+
+    Flag values for describing pipeline options.
+
+    \value CompileShadersWithDebugInfo Requests compiling shaders with debug
+    information enabled, when applicable. See
+    QRhiGraphicsPipeline::CompileShadersWithDebugInfo for more information.
+ */
+
+/*!
     \return the resource type.
  */
 QRhiResource::Type QRhiComputePipeline::resourceType() const
diff --git a/src/gui/rhi/qrhi_p.h b/src/gui/rhi/qrhi_p.h
index dd8ab862e4..7d719fd218 100644
--- a/src/gui/rhi/qrhi_p.h
+++ b/src/gui/rhi/qrhi_p.h
@@ -1024,7 +1024,8 @@ public:
     enum Flag {
         UsesBlendConstants = 1 << 0,
         UsesStencilRef = 1 << 1,
-        UsesScissor = 1 << 2
+        UsesScissor = 1 << 2,
+        CompileShadersWithDebugInfo = 1 << 3
     };
     Q_DECLARE_FLAGS(Flags, Flag)
 
@@ -1289,9 +1290,17 @@ Q_DECLARE_OPERATORS_FOR_FLAGS(QRhiSwapChain::Flags)
 class Q_GUI_EXPORT QRhiComputePipeline : public QRhiResource
 {
 public:
+    enum Flag {
+        CompileShadersWithDebugInfo = 1 << 0
+    };
+    Q_DECLARE_FLAGS(Flags, Flag)
+
     QRhiResource::Type resourceType() const override;
     virtual bool create() = 0;
 
+    Flags flags() const { return m_flags; }
+    void setFlags(Flags f) { m_flags = f; }
+
     QRhiShaderStage shaderStage() const { return m_shaderStage; }
     void setShaderStage(const QRhiShaderStage &stage) { m_shaderStage = stage; }
 
@@ -1300,10 +1309,13 @@ public:
 
 protected:
     QRhiComputePipeline(QRhiImplementation *rhi);
+    Flags m_flags;
     QRhiShaderStage m_shaderStage;
     QRhiShaderResourceBindings *m_shaderResourceBindings = nullptr;
 };
 
+Q_DECLARE_OPERATORS_FOR_FLAGS(QRhiComputePipeline::Flags)
+
 class Q_GUI_EXPORT QRhiCommandBuffer : public QRhiResource
 {
 public:
diff --git a/src/gui/rhi/qrhid3d11.cpp b/src/gui/rhi/qrhid3d11.cpp
index f105d01e4f..71b8e48da0 100644
--- a/src/gui/rhi/qrhid3d11.cpp
+++ b/src/gui/rhi/qrhid3d11.cpp
@@ -3698,7 +3698,8 @@ static pD3DCompile resolveD3DCompile()
     return nullptr;
 }
 
-static QByteArray compileHlslShaderSource(const QShader &shader, QShader::Variant shaderVariant, QString *error, QShaderKey *usedShaderKey)
+static QByteArray compileHlslShaderSource(const QShader &shader, QShader::Variant shaderVariant, UINT flags,
+                                          QString *error, QShaderKey *usedShaderKey)
 {
     QShaderKey key = { QShader::DxbcShader, 50, shaderVariant };
     QShaderCode dxbc = shader.shader(key);
@@ -3750,7 +3751,7 @@ static QByteArray compileHlslShaderSource(const QShader &shader, QShader::Varian
     ID3DBlob *errors = nullptr;
     HRESULT hr = d3dCompile(hlslSource.shader().constData(), SIZE_T(hlslSource.shader().size()),
                             nullptr, nullptr, nullptr,
-                            hlslSource.entryPoint().constData(), target, 0, 0, &bytecode, &errors);
+                            hlslSource.entryPoint().constData(), target, flags, 0, &bytecode, &errors);
     if (FAILED(hr) || !bytecode) {
         qWarning("HLSL shader compilation failed: 0x%x", uint(hr));
         if (errors) {
@@ -3871,7 +3872,12 @@ bool QD3D11GraphicsPipeline::create()
         } else {
             QString error;
             QShaderKey shaderKey;
-            const QByteArray bytecode = compileHlslShaderSource(shaderStage.shader(), shaderStage.shaderVariant(), &error, &shaderKey);
+            UINT compileFlags = 0;
+            if (m_flags.testFlag(CompileShadersWithDebugInfo))
+                compileFlags |= D3DCOMPILE_DEBUG;
+
+            const QByteArray bytecode = compileHlslShaderSource(shaderStage.shader(), shaderStage.shaderVariant(), compileFlags,
+                                                                &error, &shaderKey);
             if (bytecode.isEmpty()) {
                 qWarning("HLSL shader compilation failed: %s", qPrintable(error));
                 return false;
@@ -3987,7 +3993,12 @@ bool QD3D11ComputePipeline::create()
     } else {
         QString error;
         QShaderKey shaderKey;
-        const QByteArray bytecode = compileHlslShaderSource(m_shaderStage.shader(), m_shaderStage.shaderVariant(), &error, &shaderKey);
+        UINT compileFlags = 0;
+        if (m_flags.testFlag(CompileShadersWithDebugInfo))
+            compileFlags |= D3DCOMPILE_DEBUG;
+
+        const QByteArray bytecode = compileHlslShaderSource(m_shaderStage.shader(), m_shaderStage.shaderVariant(), compileFlags,
+                                                            &error, &shaderKey);
         if (bytecode.isEmpty()) {
             qWarning("HLSL compute shader compilation failed: %s", qPrintable(error));
             return false;