Add COM API for querying metadata. (#5168)

* Add COM API for querying metadata.

* Fix tests.

* fix test.

17 files changed, 360 insertions, 37 deletions

diff --git a/include/slang.h b/include/slang.h
index 8e42632ff..81b3ac1cb 100644
--- a/include/slang.h
+++ b/include/slang.h
@@ -5280,6 +5280,22 @@ namespace slang
 
     #define SLANG_UUID_ISession ISession::getTypeGuid()
 
+    struct IMetadata : public ISlangCastable
+    {
+        SLANG_COM_INTERFACE(0x8044a8a3, 0xddc0, 0x4b7f, { 0xaf, 0x8e, 0x2, 0x6e, 0x90, 0x5d, 0x73, 0x32 })
+
+        /*
+        Returns whether a resource parameter at the specifieid binding location is actually being used
+        in the compiled shader.
+        */
+        virtual SlangResult isParameterLocationUsed(
+            SlangParameterCategory category, // is this a `t` register? `s` register?
+            SlangUInt spaceIndex,      // `space` for D3D12, `set` for Vulkan
+            SlangUInt registerIndex,   // `register` for D3D12, `binding` for Vulkan
+            bool& outUsed) = 0;
+    };
+    #define SLANG_UUID_IMetadata IMetadata::getTypeGuid()
+
         /** A component type is a unit of shader code layout, reflection, and linking.
 
         A component type is a unit of shader code that can be included into
@@ -5492,6 +5508,17 @@ namespace slang
             SlangInt targetIndex,
             IBlob** outCode,
             IBlob** outDiagnostics = nullptr) = 0;
+
+        virtual SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt targetIndex,
+            IMetadata** outMetadata,
+            IBlob** outDiagnostics = nullptr) = 0;
+
+        virtual SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt entryPointIndex,
+            SlangInt targetIndex,
+            IMetadata** outMetadata,
+            IBlob** outDiagnostics = nullptr) = 0;
     };
     #define SLANG_UUID_IComponentType IComponentType::getTypeGuid()
 
diff --git a/source/compiler-core/slang-artifact-associated-impl.cpp b/source/compiler-core/slang-artifact-associated-impl.cpp
index f29c0f596..07d69bf8e 100644
--- a/source/compiler-core/slang-artifact-associated-impl.cpp
+++ b/source/compiler-core/slang-artifact-associated-impl.cpp
@@ -313,4 +313,24 @@ Slice<String> ArtifactPostEmitMetadata::getExportedFunctionMangledNames()
     return Slice<String>(m_exportedFunctionMangledNames.getBuffer(), m_exportedFunctionMangledNames.getCount());
 }
 
+SlangResult ArtifactPostEmitMetadata::isParameterLocationUsed(
+    SlangParameterCategory category,
+    SlangUInt spaceIndex,
+    SlangUInt registerIndex,
+    bool& outUsed)
+{
+    for (const auto& range : getUsedBindingRanges())
+    {
+        if (range.containsBinding((slang::ParameterCategory)category, spaceIndex, registerIndex))
+        {
+            outUsed = true;
+            return SLANG_OK;
+        }
+    }
+
+    outUsed = false;
+    return SLANG_OK;
+}
+
+
 } // namespace Slang
diff --git a/source/compiler-core/slang-artifact-associated-impl.h b/source/compiler-core/slang-artifact-associated-impl.h
index a6e323b0a..d11498604 100644
--- a/source/compiler-core/slang-artifact-associated-impl.h
+++ b/source/compiler-core/slang-artifact-associated-impl.h
@@ -134,6 +134,7 @@ struct ShaderBindingRange
         case slang::ShaderResource:
         case slang::UnorderedAccess:
         case slang::SamplerState:
+        case slang::DescriptorTableSlot:
             return true;
         default:
             return false;
@@ -157,6 +158,13 @@ public:
     SLANG_NO_THROW virtual Slice<ShaderBindingRange> SLANG_MCALL getUsedBindingRanges() SLANG_OVERRIDE;
     SLANG_NO_THROW virtual Slice<String> SLANG_MCALL getExportedFunctionMangledNames() SLANG_OVERRIDE;
 
+    // IMetadata
+    SLANG_NO_THROW virtual SlangResult SLANG_MCALL isParameterLocationUsed(
+        SlangParameterCategory category, // is this a `t` register? `s` register?
+        SlangUInt spaceIndex,      // `space` for D3D12, `set` for Vulkan
+        SlangUInt registerIndex,   // `register` for D3D12, `binding` for Vulkan
+        bool& outUsed) SLANG_OVERRIDE;
+
     void* getInterface(const Guid& uuid);
     void* getObject(const Guid& uuid);
 
diff --git a/source/compiler-core/slang-artifact-associated.h b/source/compiler-core/slang-artifact-associated.h
index 766494271..91ae09aab 100644
--- a/source/compiler-core/slang-artifact-associated.h
+++ b/source/compiler-core/slang-artifact-associated.h
@@ -117,7 +117,7 @@ public:
 
 struct ShaderBindingRange;
 
-class IArtifactPostEmitMetadata : public ICastable
+class IArtifactPostEmitMetadata : public slang::IMetadata
 {
 public:
     SLANG_COM_INTERFACE(0x5d03bce9, 0xafb1, 0x4fc8, { 0xa4, 0x6f, 0x3c, 0xe0, 0x7b, 0x6, 0x1b, 0x1b });
diff --git a/source/slang-record-replay/record/slang-component-type.cpp b/source/slang-record-replay/record/slang-component-type.cpp
index 5ebf73574..bc38acfae 100644
--- a/source/slang-record-replay/record/slang-component-type.cpp
+++ b/source/slang-record-replay/record/slang-component-type.cpp
@@ -127,6 +127,25 @@ namespace SlangRecord
         return res;
     }
 
+    SLANG_NO_THROW SlangResult SLANG_MCALL IComponentTypeRecorder::getEntryPointMetadata(
+        SlangInt entryPointIndex,
+        SlangInt targetIndex,
+        slang::IMetadata** outMetadata,
+        slang::IBlob** outDiagnostics)
+    {
+        // No need to record this call.
+        return m_actualComponentType->getEntryPointMetadata(entryPointIndex, targetIndex, outMetadata, outDiagnostics);
+    }
+
+    SLANG_NO_THROW SlangResult SLANG_MCALL IComponentTypeRecorder::getTargetMetadata(
+        SlangInt targetIndex,
+        slang::IMetadata** outMetadata,
+        slang::IBlob** outDiagnostics)
+    {
+        // No need to record this call.
+        return m_actualComponentType->getTargetMetadata(targetIndex, outMetadata, outDiagnostics);
+    }
+
     SLANG_NO_THROW SlangResult IComponentTypeRecorder::getResultAsFileSystem(
         SlangInt    entryPointIndex,
         SlangInt    targetIndex,
diff --git a/source/slang-record-replay/record/slang-component-type.h b/source/slang-record-replay/record/slang-component-type.h
index 110733044..52e07d9c0 100644
--- a/source/slang-record-replay/record/slang-component-type.h
+++ b/source/slang-record-replay/record/slang-component-type.h
@@ -61,6 +61,15 @@ namespace SlangRecord
             SlangInt    targetIndex,
             slang::IBlob** outCode,
             slang::IBlob** outDiagnostics = nullptr) override;
+        virtual SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt        entryPointIndex,
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) override;
+        virtual SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics = nullptr) override;
     protected:
         virtual ApiClassId getClassId() = 0;
         virtual SessionRecorder* getSessionRecorder() = 0;
diff --git a/source/slang-record-replay/record/slang-entrypoint.h b/source/slang-record-replay/record/slang-entrypoint.h
index abe2dc9c0..29a3329fe 100644
--- a/source/slang-record-replay/record/slang-entrypoint.h
+++ b/source/slang-record-replay/record/slang-entrypoint.h
@@ -69,6 +69,23 @@ namespace SlangRecord
             return Super::getTargetCode(targetIndex, outCode, outDiagnostics);
         }
 
+        SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt        entryPointIndex,
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getEntryPointMetadata(entryPointIndex, targetIndex, outMetadata, outDiagnostics);
+        }
+
+        SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getTargetMetadata(targetIndex, outMetadata, outDiagnostics);
+        }
+
         virtual SLANG_NO_THROW SlangResult SLANG_MCALL getResultAsFileSystem(
             SlangInt    entryPointIndex,
             SlangInt    targetIndex,
diff --git a/source/slang-record-replay/record/slang-module.h b/source/slang-record-replay/record/slang-module.h
index e793bea98..ce009eac8 100644
--- a/source/slang-record-replay/record/slang-module.h
+++ b/source/slang-record-replay/record/slang-module.h
@@ -85,6 +85,23 @@ namespace SlangRecord
             return Super::getTargetCode(targetIndex, outCode, outDiagnostics);
         }
 
+        SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt        entryPointIndex,
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getEntryPointMetadata(entryPointIndex, targetIndex, outMetadata, outDiagnostics);
+        }
+
+        SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getTargetMetadata(targetIndex, outMetadata, outDiagnostics);
+        }
+
         virtual SLANG_NO_THROW SlangResult SLANG_MCALL getResultAsFileSystem(
             SlangInt    entryPointIndex,
             SlangInt    targetIndex,
diff --git a/source/slang-record-replay/record/slang-type-conformance.h b/source/slang-record-replay/record/slang-type-conformance.h
index d1dfb3238..6c6889d02 100644
--- a/source/slang-record-replay/record/slang-type-conformance.h
+++ b/source/slang-record-replay/record/slang-type-conformance.h
@@ -65,6 +65,23 @@ namespace SlangRecord
             return Super::getTargetCode(targetIndex, outCode, outDiagnostics);
         }
 
+        SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt        entryPointIndex,
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getEntryPointMetadata(entryPointIndex, targetIndex, outMetadata, outDiagnostics);
+        }
+
+        SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getTargetMetadata(targetIndex, outMetadata, outDiagnostics);
+        }
+
         virtual SLANG_NO_THROW SlangResult SLANG_MCALL getResultAsFileSystem(
             SlangInt    entryPointIndex,
             SlangInt    targetIndex,
diff --git a/source/slang/slang-compiler.h b/source/slang/slang-compiler.h
index 820cab03f..17501163f 100755
--- a/source/slang/slang-compiler.h
+++ b/source/slang/slang-compiler.h
@@ -317,10 +317,22 @@ namespace Slang
             SlangInt        targetIndex,
             slang::IBlob**  outCode,
             slang::IBlob**  outDiagnostics) SLANG_OVERRIDE;
+
+        IArtifact* getTargetArtifact(SlangInt targetIndex, slang::IBlob** outDiagnostics);
+
         SLANG_NO_THROW SlangResult SLANG_MCALL getTargetCode(
             SlangInt targetIndex,
             slang::IBlob** outCode,
             slang::IBlob** outDiagnostics = nullptr) SLANG_OVERRIDE;
+        SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt        entryPointIndex,
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE;
+        SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics = nullptr) SLANG_OVERRIDE;
 
         SLANG_NO_THROW SlangResult SLANG_MCALL getResultAsFileSystem(
             SlangInt    entryPointIndex,
@@ -580,6 +592,8 @@ namespace Slang
 
         Scope* m_lookupScope = nullptr;
         std::unique_ptr<Dictionary<String, IntVal*>> m_mapMangledNameToIntVal;
+
+        Dictionary<Int, ComPtr<IArtifact>> m_targetArtifacts;
     };
 
         /// A component type built up from other component types.
@@ -914,6 +928,23 @@ namespace Slang
             return Super::getTargetCode(targetIndex, outCode, outDiagnostics);
         }
 
+        SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt        entryPointIndex,
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getEntryPointMetadata(entryPointIndex, targetIndex, outMetadata, outDiagnostics);
+        }
+
+        SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getTargetMetadata(targetIndex, outMetadata, outDiagnostics);
+        }
+
         SLANG_NO_THROW SlangResult SLANG_MCALL getResultAsFileSystem(
             SlangInt        entryPointIndex,
             SlangInt        targetIndex,
@@ -1159,6 +1190,23 @@ namespace Slang
             return Super::getTargetCode(targetIndex, outCode, outDiagnostics);
         }
 
+        SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt        entryPointIndex,
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getEntryPointMetadata(entryPointIndex, targetIndex, outMetadata, outDiagnostics);
+        }
+
+        SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getTargetMetadata(targetIndex, outMetadata, outDiagnostics);
+        }
+
         SLANG_NO_THROW SlangResult SLANG_MCALL getResultAsFileSystem(
             SlangInt        entryPointIndex,
             SlangInt        targetIndex,
@@ -1460,6 +1508,23 @@ namespace Slang
             return Super::getEntryPointHash(entryPointIndex, targetIndex, outHash);
         }
 
+        SLANG_NO_THROW SlangResult SLANG_MCALL getEntryPointMetadata(
+            SlangInt        entryPointIndex,
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getEntryPointMetadata(entryPointIndex, targetIndex, outMetadata, outDiagnostics);
+        }
+
+        SLANG_NO_THROW SlangResult SLANG_MCALL getTargetMetadata(
+            SlangInt        targetIndex,
+            slang::IMetadata** outMetadata,
+            slang::IBlob** outDiagnostics) SLANG_OVERRIDE
+        {
+            return Super::getTargetMetadata(targetIndex, outMetadata, outDiagnostics);
+        }
+
         /// Get a serialized representation of the checked module.
         virtual SLANG_NO_THROW SlangResult SLANG_MCALL serialize(ISlangBlob** outSerializedBlob) override;
 
diff --git a/source/slang/slang-parameter-binding.cpp b/source/slang/slang-parameter-binding.cpp
index ea22cbcba..5d3331c6f 100644
--- a/source/slang/slang-parameter-binding.cpp
+++ b/source/slang/slang-parameter-binding.cpp
@@ -1225,10 +1225,6 @@ static void addExplicitParameterBindings_GLSL(
         }
     }
 
-    // We use the HLSL binding directly (even though this notionally for GLSL/Vulkan)
-    // We'll do the shifting at later later point in _maybeApplyHLSLToVulkanShifts
-    info[kResInfo].resInfo = typeLayout->findOrAddResourceInfo(hlslInfo.kind);
-
     if (warnedMissingVulkanLayoutModifier)
     {
         // If we warn due to invalid bindings and user did not set how to interpret 'hlsl style bindings', we should map 
@@ -1236,7 +1232,7 @@ static void addExplicitParameterBindings_GLSL(
         if(!hlslToVulkanLayoutOptions
             || hlslToVulkanLayoutOptions->getKindShiftEnabledFlags() == HLSLToVulkanLayoutOptions::KindFlag::None)
         {
-            info[kResInfo].resInfo->kind = LayoutResourceKind::DescriptorTableSlot;
+            info[kResInfo].resInfo = typeLayout->findOrAddResourceInfo(LayoutResourceKind::DescriptorTableSlot);
             info[kResInfo].resInfo->count = 1;
         }
         else
@@ -1245,6 +1241,11 @@ static void addExplicitParameterBindings_GLSL(
         }
     }
 
+    // We use the HLSL binding directly (even though this notionally for GLSL/Vulkan)
+    // We'll do the shifting at later later point in _maybeApplyHLSLToVulkanShifts
+    if (!info[kResInfo].resInfo)
+        info[kResInfo].resInfo = typeLayout->findOrAddResourceInfo(hlslInfo.kind);
+
     info[kResInfo].semanticInfo.kind = info[kResInfo].resInfo->kind;
     info[kResInfo].semanticInfo.index = UInt(hlslInfo.index);
     info[kResInfo].semanticInfo.space = UInt(hlslInfo.space);
diff --git a/source/slang/slang.cpp b/source/slang/slang.cpp
index dc5f9a755..c9717272b 100644
--- a/source/slang/slang.cpp
+++ b/source/slang/slang.cpp
@@ -4704,6 +4704,38 @@ SLANG_NO_THROW SlangResult SLANG_MCALL ComponentType::getEntryPointHostCallable(
     return artifact->loadSharedLibrary(ArtifactKeep::Yes, outSharedLibrary);
 }
 
+SLANG_NO_THROW SlangResult SLANG_MCALL ComponentType::getEntryPointMetadata(
+    SlangInt        entryPointIndex,
+    Int             targetIndex,
+    slang::IMetadata** outMetadata,
+    slang::IBlob** outDiagnostics)
+{
+    auto linkage = getLinkage();
+    if (targetIndex < 0 || targetIndex >= linkage->targets.getCount())
+        return SLANG_E_INVALID_ARG;
+    auto target = linkage->targets[targetIndex];
+
+    auto targetProgram = getTargetProgram(target);
+
+    DiagnosticSink sink(linkage->getSourceManager(), Lexer::sourceLocationLexer);
+    applySettingsToDiagnosticSink(&sink, &sink, linkage->m_optionSet);
+    applySettingsToDiagnosticSink(&sink, &sink, m_optionSet);
+
+    IArtifact* artifact = targetProgram->getOrCreateEntryPointResult(entryPointIndex, &sink);
+    sink.getBlobIfNeeded(outDiagnostics);
+
+    if (artifact == nullptr)
+        return SLANG_E_NOT_AVAILABLE;
+
+    auto metadata = findAssociatedRepresentation<IArtifactPostEmitMetadata>(artifact);
+    if (!metadata)
+        return SLANG_E_NOT_AVAILABLE;
+
+    *outMetadata = static_cast<slang::IMetadata*>(metadata);
+    (*outMetadata)->addRef();
+    return SLANG_OK;
+}
+
 RefPtr<ComponentType> ComponentType::specialize(
     SpecializationArg const*    inSpecializationArgs,
     SlangInt                    specializationArgCount,
@@ -4933,14 +4965,16 @@ void ComponentType::enumerateIRModules(EnumerateIRModulesCallback callback, void
     acceptVisitor(&visitor, nullptr);
 }
 
-SLANG_NO_THROW SlangResult SLANG_MCALL ComponentType::getTargetCode(
-    Int             targetIndex,
-    slang::IBlob** outCode,
-    slang::IBlob** outDiagnostics)
+IArtifact* ComponentType::getTargetArtifact(Int targetIndex, slang::IBlob** outDiagnostics)
 {
     auto linkage = getLinkage();
     if (targetIndex < 0 || targetIndex >= linkage->targets.getCount())
-        return SLANG_E_INVALID_ARG;
+        return nullptr;
+    ComPtr<IArtifact> artifact;
+    if (m_targetArtifacts.tryGetValue(targetIndex, artifact))
+    {
+        return artifact.get();
+    }
 
     // If the user hasn't specified any entry points, then we should
     // discover all entrypoints that are defined in linked modules, and
@@ -4964,8 +4998,13 @@ SLANG_NO_THROW SlangResult SLANG_MCALL ComponentType::getTargetCode(
         }
         RefPtr<CompositeComponentType> composite = new CompositeComponentType(linkage, components);
         ComPtr<IComponentType> linkedComponentType;
-        SLANG_RETURN_ON_FAIL(composite->link(linkedComponentType.writeRef(), outDiagnostics));
-        return linkedComponentType->getTargetCode(targetIndex, outCode, outDiagnostics);
+        SLANG_RETURN_NULL_ON_FAIL(composite->link(linkedComponentType.writeRef(), outDiagnostics));
+        auto targetArtifact = static_cast<ComponentType*>(linkedComponentType.get())->getTargetArtifact(targetIndex, outDiagnostics);
+        if (targetArtifact)
+        {
+            m_targetArtifacts[targetIndex] = targetArtifact;
+        }
+        return targetArtifact;
     }
 
     auto target = linkage->targets[targetIndex];
@@ -4975,8 +5014,18 @@ SLANG_NO_THROW SlangResult SLANG_MCALL ComponentType::getTargetCode(
     applySettingsToDiagnosticSink(&sink, &sink, linkage->m_optionSet);
     applySettingsToDiagnosticSink(&sink, &sink, m_optionSet);
 
-    IArtifact* artifact = targetProgram->getOrCreateWholeProgramResult(&sink);
+    IArtifact* targetArtifact = targetProgram->getOrCreateWholeProgramResult(&sink);
     sink.getBlobIfNeeded(outDiagnostics);
+    m_targetArtifacts[targetIndex] = ComPtr<IArtifact>(targetArtifact);
+    return targetArtifact;
+}
+
+SLANG_NO_THROW SlangResult SLANG_MCALL ComponentType::getTargetCode(
+    Int             targetIndex,
+    slang::IBlob** outCode,
+    slang::IBlob** outDiagnostics)
+{
+    IArtifact* artifact = getTargetArtifact(targetIndex, outDiagnostics);
 
     if (artifact == nullptr)
         return SLANG_FAIL;
@@ -4984,6 +5033,24 @@ SLANG_NO_THROW SlangResult SLANG_MCALL ComponentType::getTargetCode(
     return artifact->loadBlob(ArtifactKeep::Yes, outCode);
 }
 
+SLANG_NO_THROW SlangResult SLANG_MCALL ComponentType::getTargetMetadata(
+    Int             targetIndex,
+    slang::IMetadata** outMetadata,
+    slang::IBlob** outDiagnostics)
+{
+    IArtifact* artifact = getTargetArtifact(targetIndex, outDiagnostics);
+
+    if (artifact == nullptr)
+        return SLANG_FAIL;
+
+    auto metadata = findAssociatedRepresentation<IArtifactPostEmitMetadata>(artifact);
+    if (!metadata)
+        return SLANG_E_NOT_AVAILABLE;
+    *outMetadata = static_cast<slang::IMetadata*>(metadata);
+    (*outMetadata)->addRef();
+    return SLANG_OK;
+}
+
 //
 // CompositeComponentType
 //
@@ -6888,19 +6955,7 @@ SlangResult EndToEndCompileRequest::isParameterLocationUsed(Int entryPointIndex,
     if (!metadata)
         return SLANG_E_NOT_AVAILABLE;
 
-
-    // TODO: optimize this with a binary search through a sorted list
-    for (const auto& range : metadata->getUsedBindingRanges())
-    {
-        if (range.containsBinding((slang::ParameterCategory)category, spaceIndex, registerIndex))
-        {
-            outUsed = true;
-            return SLANG_OK;
-        }
-    }
-
-    outUsed = false;
-    return SLANG_OK;
+    return metadata->isParameterLocationUsed(category, spaceIndex, registerIndex, outUsed);
 }
 
 } // namespace Slang
diff --git a/tests/bindings/hlsl-to-vulkan-combined.hlsl.expected b/tests/bindings/hlsl-to-vulkan-combined.hlsl.expected
index de67a3592..7466a276d 100644
--- a/tests/bindings/hlsl-to-vulkan-combined.hlsl.expected
+++ b/tests/bindings/hlsl-to-vulkan-combined.hlsl.expected
@@ -41,11 +41,11 @@ standard output = {
             "bindings": [
                 {
                     "name": "t0",
-                    "binding": {"kind": "descriptorTableSlot", "index": 0}
+                    "binding": {"kind": "descriptorTableSlot", "index": 0, "used": 0}
                 },
                 {
                     "name": "t1",
-                    "binding": {"kind": "descriptorTableSlot", "index": 1}
+                    "binding": {"kind": "descriptorTableSlot", "index": 1, "used": 0}
                 }
             ]
         }
diff --git a/tests/bindings/hlsl-to-vulkan-global.hlsl.expected b/tests/bindings/hlsl-to-vulkan-global.hlsl.expected
index b0b8f6a17..e0e0db832 100644
--- a/tests/bindings/hlsl-to-vulkan-global.hlsl.expected
+++ b/tests/bindings/hlsl-to-vulkan-global.hlsl.expected
@@ -64,11 +64,11 @@ standard output = {
                 },
                 {
                     "name": "t",
-                    "binding": {"kind": "descriptorTableSlot", "index": 0}
+                    "binding": {"kind": "descriptorTableSlot", "index": 0, "used": 1}
                 },
                 {
                     "name": "sampler",
-                    "binding": {"kind": "descriptorTableSlot", "index": 1}
+                    "binding": {"kind": "descriptorTableSlot", "index": 1, "used": 1}
                 }
             ]
         }
diff --git a/tests/slang-extension/dynamic-resource-gl.slang.1.expected b/tests/slang-extension/dynamic-resource-gl.slang.1.expected
index fe48e643a..703cb1229 100644
--- a/tests/slang-extension/dynamic-resource-gl.slang.1.expected
+++ b/tests/slang-extension/dynamic-resource-gl.slang.1.expected
@@ -70,23 +70,23 @@ standard output = {
             "bindings": [
                 {
                     "name": "g_TextureHeap",
-                    "binding": {"kind": "descriptorTableSlot", "space": 1, "index": 0}
+                    "binding": {"kind": "descriptorTableSlot", "space": 1, "index": 0, "used": 1}
                 },
                 {
                     "name": "g_SamplerHeap",
-                    "binding": {"kind": "descriptorTableSlot", "space": 1, "index": 2}
+                    "binding": {"kind": "descriptorTableSlot", "space": 1, "index": 2, "used": 1}
                 },
                 {
                     "name": "g_SingleDynamicResourceA",
-                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 0}
+                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 0, "used": 1}
                 },
                 {
                     "name": "g_SingleDynamicResourceB",
-                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 1}
+                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 1, "used": 1}
                 },
                 {
                     "name": "g_SingleDynamicResourceC",
-                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 2}
+                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 2, "used": 1}
                 }
             ]
         }
diff --git a/tools/slang-unit-test/unit-test-image-format-reflection.cpp b/tools/slang-unit-test/unit-test-image-format-reflection.cpp
index 2ada598b4..34678472c 100644
--- a/tools/slang-unit-test/unit-test-image-format-reflection.cpp
+++ b/tools/slang-unit-test/unit-test-image-format-reflection.cpp
@@ -1,4 +1,4 @@
-// unit-test-translation-unit-import.cpp
+// unit-test-image-format-reflection.cpp
 
 #include "slang.h"
 
diff --git a/tools/slang-unit-test/unit-test-parameter-usage-reflection.cpp b/tools/slang-unit-test/unit-test-parameter-usage-reflection.cpp
new file mode 100644
index 000000000..911bdc5a4
--- /dev/null
+++ b/tools/slang-unit-test/unit-test-parameter-usage-reflection.cpp
@@ -0,0 +1,68 @@
+// unit-test-parameter-usage-reflection.cpp
+
+#include "slang.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "tools/unit-test/slang-unit-test.h"
+#include "slang-com-ptr.h"
+#include "../../source/core/slang-io.h"
+#include "../../source/core/slang-process.h"
+
+using namespace Slang;
+
+// Test that the isParameterLocationUsed API works.
+
+SLANG_UNIT_TEST(isParameterLocationUsedReflection)
+{
+    // Source for a module that contains an undecorated entrypoint.
+    const char* userSourceBody = R"(
+        Texture2D g_tex : register(t0);
+        [shader("fragment")]
+        float4 fragMain(float4 pos:SV_Position) : SV_Target
+        {
+            return g_tex.Load(int3(0, 0, 0));
+        }
+        )";
+
+    auto moduleName = "moduleG" + String(Process::getId());
+    String userSource = "import " + moduleName + ";\n" + userSourceBody;
+    ComPtr<slang::IGlobalSession> globalSession;
+    SLANG_CHECK(slang_createGlobalSession(SLANG_API_VERSION, globalSession.writeRef()) == SLANG_OK);
+    slang::TargetDesc targetDesc = {};
+    targetDesc.format = SLANG_SPIRV;
+    targetDesc.profile = globalSession->findProfile("spirv_1_5");
+    slang::SessionDesc sessionDesc = {};
+    sessionDesc.targetCount = 1;
+    sessionDesc.targets = &targetDesc;
+    ComPtr<slang::ISession> session;
+    SLANG_CHECK(globalSession->createSession(sessionDesc, session.writeRef()) == SLANG_OK);
+
+    ComPtr<slang::IBlob> diagnosticBlob;
+    auto module = session->loadModuleFromSourceString("m", "m.slang", userSourceBody, diagnosticBlob.writeRef());
+    SLANG_CHECK(module != nullptr);
+
+    ComPtr<slang::IEntryPoint> entryPoint;
+    module->findAndCheckEntryPoint("fragMain", SLANG_STAGE_FRAGMENT, entryPoint.writeRef(), diagnosticBlob.writeRef());
+    SLANG_CHECK(entryPoint != nullptr);
+
+    ComPtr<slang::IComponentType> compositeProgram;
+    slang::IComponentType* components[] = { module, entryPoint.get() };
+    session->createCompositeComponentType(components, 2, compositeProgram.writeRef(), diagnosticBlob.writeRef());
+    SLANG_CHECK(compositeProgram != nullptr);
+
+    ComPtr<slang::IComponentType> linkedProgram;
+    compositeProgram->link(linkedProgram.writeRef(), nullptr);
+
+    ComPtr<slang::IMetadata> metadata;
+    linkedProgram->getTargetMetadata(0, metadata.writeRef(), nullptr);
+
+    bool isUsed = false;
+    metadata->isParameterLocationUsed(SLANG_PARAMETER_CATEGORY_DESCRIPTOR_TABLE_SLOT, 0, 0, isUsed);
+    SLANG_CHECK(isUsed);
+
+    metadata->isParameterLocationUsed(SLANG_PARAMETER_CATEGORY_DESCRIPTOR_TABLE_SLOT, 0, 1, isUsed);
+    SLANG_CHECK(!isUsed);
+}
+