Reland "Document thread-unsafe iterator access to resource maps"

This is a reland of commit d1bb6ed8399dd12e79484f30f9e9ded95c25625a

The crash was due to another issue (disabling EGL validation in
Chrome)

Original change's description:
> Document thread-unsafe iterator access to resource maps
>
> By using a proxy type, everywhere resource maps are iterated are clearly
> marked as not being thread safe.  In most cases, only destruction and
> capture/replay iterate over these maps, which means thread safety is not
> an issue (or is externally enforced).
>
> The only case where iterators are used in the presence of other contexts
> is with ANGLE_request_extension, which is changed to explicitly require
> the application to ensure thread safety.  In practice, the user is
> Chrome which already guarantees this.
>
> Bug: angleproject:8667
> Change-Id: I7af13c6433b6955d9c36f9088b3aa4c065e1cfc1
> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5526428
> Reviewed-by: Charlie Lao <cclao@google.com>
> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
> Reviewed-by: Geoff Lang <geofflang@chromium.org>

Bug: angleproject:8667
Change-Id: Id539cabac01df5f242150f6684222577003eef3f
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5531278
Reviewed-by: Charlie Lao <cclao@google.com>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>

8 files changed, 124 insertions, 65 deletions

diff --git a/extensions/ANGLE_request_extension.txt b/extensions/ANGLE_request_extension.txt
index 88d3422e3b..56317e6d6a 100644
--- a/extensions/ANGLE_request_extension.txt
+++ b/extensions/ANGLE_request_extension.txt
@@ -85,7 +85,9 @@ Additions to the OpenGL ES 3.0 Specification
     enable or disable the requestable OpenGL ES extension named <name>. If the
     requested extension was not requestable or disablable, INVALID_OPERATION is
     generated. Not all requestable extensions can be disabled. There is
-    currently no query for disablable extensions.
+    currently no query for disablable extensions.  This operation is not thread
+    safe, and the application is responsible for ensuring no other context in
+    the share group is accessed by another thread during this operation.
 
 New State
 
diff --git a/src/libANGLE/Context.cpp b/src/libANGLE/Context.cpp
index 1b23bd94a8..5eda734ca6 100644
--- a/src/libANGLE/Context.cpp
+++ b/src/libANGLE/Context.cpp
@@ -850,7 +850,7 @@ egl::Error Context::onDestroy(const egl::Display *display)
     mDefaultFramebuffer->onDestroy(this);
     mDefaultFramebuffer.reset();
 
-    for (auto fence : mFenceNVMap)
+    for (auto fence : UnsafeResourceMapIter(mFenceNVMap))
     {
         if (fence.second)
         {
@@ -860,7 +860,7 @@ egl::Error Context::onDestroy(const egl::Display *display)
     }
     mFenceNVMap.clear();
 
-    for (auto query : mQueryMap)
+    for (auto query : UnsafeResourceMapIter(mQueryMap))
     {
         if (query.second != nullptr)
         {
@@ -869,7 +869,7 @@ egl::Error Context::onDestroy(const egl::Display *display)
     }
     mQueryMap.clear();
 
-    for (auto vertexArray : mVertexArrayMap)
+    for (auto vertexArray : UnsafeResourceMapIter(mVertexArrayMap))
     {
         if (vertexArray.second)
         {
@@ -878,7 +878,7 @@ egl::Error Context::onDestroy(const egl::Display *display)
     }
     mVertexArrayMap.clear();
 
-    for (auto transformFeedback : mTransformFeedbackMap)
+    for (auto transformFeedback : UnsafeResourceMapIter(mTransformFeedbackMap))
     {
         if (transformFeedback.second != nullptr)
         {
@@ -3618,7 +3618,8 @@ void Context::beginTransformFeedback(PrimitiveMode primitiveMode)
 
 bool Context::hasActiveTransformFeedback(ShaderProgramID program) const
 {
-    for (auto pair : mTransformFeedbackMap)
+    // Note: transform feedback objects are private to context and so the map doesn't need locking
+    for (auto pair : UnsafeResourceMapIter(mTransformFeedbackMap))
     {
         if (pair.second != nullptr && pair.second->hasBoundProgram(program))
         {
@@ -4498,7 +4499,8 @@ void Context::updateCaps()
                                       (mState.isWebGL() || mState.hasRobustAccess()));
 
     // Cache this in the VertexArrays. They need to check it in state change notifications.
-    for (auto vaoIter : mVertexArrayMap)
+    // Note: vertex array objects are private to context and so the map doesn't need locking
+    for (auto vaoIter : UnsafeResourceMapIter(mVertexArrayMap))
     {
         VertexArray *vao = vaoIter.second;
         vao->setBufferAccessValidationEnabled(mBufferAccessValidationEnabled);
diff --git a/src/libANGLE/ResourceManager.cpp b/src/libANGLE/ResourceManager.cpp
index 8c63342b12..bf0c93d59e 100644
--- a/src/libANGLE/ResourceManager.cpp
+++ b/src/libANGLE/ResourceManager.cpp
@@ -61,14 +61,16 @@ void ResourceManagerBase::release(const Context *context)
 template <typename ResourceType, typename ImplT, typename IDType>
 TypedResourceManager<ResourceType, ImplT, IDType>::~TypedResourceManager()
 {
-    ASSERT(mObjectMap.empty());
+    ASSERT(UnsafeResourceMapIter(mObjectMap).empty());
 }
 
 template <typename ResourceType, typename ImplT, typename IDType>
 void TypedResourceManager<ResourceType, ImplT, IDType>::reset(const Context *context)
 {
+    // Note: this function is called when the last context in the share group is destroyed.  Thus
+    // there are no thread safety concerns.
     this->mHandleAllocator.reset();
-    for (const auto &resource : mObjectMap)
+    for (const auto &resource : UnsafeResourceMapIter(mObjectMap))
     {
         if (resource.second)
         {
@@ -138,21 +140,30 @@ ShaderProgramManager::ShaderProgramManager() {}
 
 ShaderProgramManager::~ShaderProgramManager()
 {
-    ASSERT(mPrograms.empty());
-    ASSERT(mShaders.empty());
+    ASSERT(UnsafeResourceMapIter(mPrograms).empty());
+    ASSERT(UnsafeResourceMapIter(mShaders).empty());
 }
 
 void ShaderProgramManager::reset(const Context *context)
 {
-    while (!mPrograms.empty())
+    // Note: this function is called when the last context in the share group is destroyed.  Thus
+    // there are no thread safety concerns.
+    mHandleAllocator.reset();
+    for (const auto &program : UnsafeResourceMapIter(mPrograms))
     {
-        deleteProgram(context, {mPrograms.begin()->first});
+        if (program.second)
+        {
+            program.second->onDestroy(context);
+        }
     }
-    mPrograms.clear();
-    while (!mShaders.empty())
+    for (const auto &shader : UnsafeResourceMapIter(mShaders))
     {
-        deleteShader(context, {mShaders.begin()->first});
+        if (shader.second)
+        {
+            shader.second->onDestroy(context);
+        }
     }
+    mPrograms.clear();
     mShaders.clear();
 }
 
@@ -238,7 +249,9 @@ TextureID TextureManager::createTexture()
 
 void TextureManager::signalAllTexturesDirty() const
 {
-    for (const auto &texture : mObjectMap)
+    // Note: this function is called with glRequestExtensionANGLE and glDisableExtensionANGLE.  The
+    // GL_ANGLE_request_extension explicitly requires the application to ensure thread safety.
+    for (const auto &texture : UnsafeResourceMapIter(mObjectMap))
     {
         if (texture.second)
         {
@@ -384,7 +397,8 @@ Framebuffer *FramebufferManager::getDefaultFramebuffer() const
 
 void FramebufferManager::invalidateFramebufferCompletenessCache() const
 {
-    for (const auto &framebuffer : mObjectMap)
+    // Note: framebuffer objects are private to context and so the map doesn't need locking
+    for (const auto &framebuffer : UnsafeResourceMapIter(mObjectMap))
     {
         if (framebuffer.second)
         {
@@ -428,14 +442,20 @@ MemoryObjectManager::MemoryObjectManager() {}
 
 MemoryObjectManager::~MemoryObjectManager()
 {
-    ASSERT(mMemoryObjects.empty());
+    ASSERT(UnsafeResourceMapIter(mMemoryObjects).empty());
 }
 
 void MemoryObjectManager::reset(const Context *context)
 {
-    while (!mMemoryObjects.empty())
+    // Note: this function is called when the last context in the share group is destroyed.  Thus
+    // there are no thread safety concerns.
+    mHandleAllocator.reset();
+    for (const auto &memoryObject : UnsafeResourceMapIter(mMemoryObjects))
     {
-        deleteMemoryObject(context, {mMemoryObjects.begin()->first});
+        if (memoryObject.second)
+        {
+            memoryObject.second->release(context);
+        }
     }
     mMemoryObjects.clear();
 }
@@ -477,14 +497,20 @@ SemaphoreManager::SemaphoreManager() {}
 
 SemaphoreManager::~SemaphoreManager()
 {
-    ASSERT(mSemaphores.empty());
+    ASSERT(UnsafeResourceMapIter(mSemaphores).empty());
 }
 
 void SemaphoreManager::reset(const Context *context)
 {
-    while (!mSemaphores.empty())
+    // Note: this function is called when the last context in the share group is destroyed.  Thus
+    // there are no thread safety concerns.
+    mHandleAllocator.reset();
+    for (const auto &semaphore : UnsafeResourceMapIter(mSemaphores))
     {
-        deleteSemaphore(context, {mSemaphores.begin()->first});
+        if (semaphore.second)
+        {
+            semaphore.second->release(context);
+        }
     }
     mSemaphores.clear();
 }
diff --git a/src/libANGLE/ResourceManager.h b/src/libANGLE/ResourceManager.h
index 710a88dd44..372b76b4b5 100644
--- a/src/libANGLE/ResourceManager.h
+++ b/src/libANGLE/ResourceManager.h
@@ -75,11 +75,7 @@ class TypedResourceManager : public ResourceManagerBase
         return GetIDValue(handle) == 0 || mObjectMap.contains(handle);
     }
 
-    typename ResourceMap<ResourceType, IDType>::Iterator begin() const
-    {
-        return mObjectMap.begin();
-    }
-    typename ResourceMap<ResourceType, IDType>::Iterator end() const { return mObjectMap.end(); }
+    const ResourceMap<ResourceType, IDType> &getResourcesForCapture() const { return mObjectMap; }
 
   protected:
     ~TypedResourceManager() override;
diff --git a/src/libANGLE/ResourceMap.h b/src/libANGLE/ResourceMap.h
index b454e261a2..92d6b6251d 100644
--- a/src/libANGLE/ResourceMap.h
+++ b/src/libANGLE/ResourceMap.h
@@ -73,6 +73,11 @@ class ResourceMap final : angle::NonCopyable
         bool mSkipNulls;
     };
 
+  private:
+    friend class Iterator;
+    template <typename SameResourceType, typename SameIDType>
+    friend class UnsafeResourceMapIter;
+
     // null values represent reserved handles.
     Iterator begin() const;
     Iterator end() const;
@@ -80,12 +85,7 @@ class ResourceMap final : angle::NonCopyable
     Iterator beginWithNull() const;
     Iterator endWithNull() const;
 
-    // Not a constant-time operation, should only be used for verification.
-    bool empty() const;
-
-  private:
-    friend class Iterator;
-
+    // Used by iterators and related functions only (due to lack of thread safety).
     GLuint nextResource(size_t flatIndex, bool skipNulls) const;
 
     // constexpr methods cannot contain reinterpret_cast, so we need a static method.
@@ -108,6 +108,30 @@ class ResourceMap final : angle::NonCopyable
     HashMap mHashedResources;
 };
 
+// A helper to retrieve the resource map iterators while being explicit that this is not thread
+// safe.  Usage of iterators are limited to clean up on destruction and capture/replay, neither of
+// which can race with other threads in their access to the resource map.
+template <typename ResourceType, typename IDType>
+class UnsafeResourceMapIter
+{
+  public:
+    using ResMap = ResourceMap<ResourceType, IDType>;
+
+    UnsafeResourceMapIter(const ResMap &resourceMap) : mResourceMap(resourceMap) {}
+
+    typename ResMap::Iterator begin() const { return mResourceMap.begin(); }
+    typename ResMap::Iterator end() const { return mResourceMap.end(); }
+
+    typename ResMap::Iterator beginWithNull() const { return mResourceMap.beginWithNull(); }
+    typename ResMap::Iterator endWithNull() const { return mResourceMap.endWithNull(); }
+
+    // Not a constant-time operation, should only be used for verification.
+    bool empty() const;
+
+  private:
+    const ResMap &mResourceMap;
+};
+
 template <typename ResourceType, typename IDType>
 ResourceMap<ResourceType, IDType>::ResourceMap()
     : mFlatResourcesSize(kInitialFlatResourcesSize),
@@ -119,7 +143,7 @@ ResourceMap<ResourceType, IDType>::ResourceMap()
 template <typename ResourceType, typename IDType>
 ResourceMap<ResourceType, IDType>::~ResourceMap()
 {
-    ASSERT(empty());
+    ASSERT(UnsafeResourceMapIter(*this).empty());
     delete[] mFlatResources;
 }
 
@@ -222,9 +246,9 @@ ResourceMap<ResourceType, IDType>::endWithNull() const
 }
 
 template <typename ResourceType, typename IDType>
-bool ResourceMap<ResourceType, IDType>::empty() const
+bool UnsafeResourceMapIter<ResourceType, IDType>::empty() const
 {
-    return (begin() == end());
+    return begin() == end();
 }
 
 template <typename ResourceType, typename IDType>
diff --git a/src/libANGLE/ResourceMap_unittest.cpp b/src/libANGLE/ResourceMap_unittest.cpp
index 056dde518a..01d2d706ba 100644
--- a/src/libANGLE/ResourceMap_unittest.cpp
+++ b/src/libANGLE/ResourceMap_unittest.cpp
@@ -33,7 +33,7 @@ TEST(ResourceMapTest, AssignAndErase)
         ASSERT_EQ(&objects[index], found);
     }
 
-    ASSERT_TRUE(resourceMap.empty());
+    ASSERT_TRUE(UnsafeResourceMapIter(resourceMap).empty());
 }
 
 // Tests assigning slots in the map and then using clear() to free it.
@@ -48,7 +48,7 @@ TEST(ResourceMapTest, AssignAndClear)
     }
 
     resourceMap.clear();
-    ASSERT_TRUE(resourceMap.empty());
+    ASSERT_TRUE(UnsafeResourceMapIter(resourceMap).empty());
 }
 
 // Tests growing a map more than double the size.
@@ -80,7 +80,7 @@ TEST(ResourceMapTest, BigGrowth)
         ASSERT_EQ(object, *found);
     }
 
-    ASSERT_TRUE(resourceMap.empty());
+    ASSERT_TRUE(UnsafeResourceMapIter(resourceMap).empty());
 }
 
 // Tests querying unassigned or erased values.
@@ -106,7 +106,7 @@ TEST(ResourceMapTest, QueryUnassigned)
         resourceMap.assign(object, &object);
     }
 
-    ASSERT_FALSE(resourceMap.empty());
+    ASSERT_FALSE(UnsafeResourceMapIter(resourceMap).empty());
 
     for (size_t &object : objects)
     {
@@ -126,7 +126,7 @@ TEST(ResourceMapTest, QueryUnassigned)
         ASSERT_EQ(object, *found);
     }
 
-    ASSERT_TRUE(resourceMap.empty());
+    ASSERT_TRUE(UnsafeResourceMapIter(resourceMap).empty());
 
     ASSERT_FALSE(resourceMap.contains(0));
     ASSERT_EQ(nullptr, resourceMap.query(0));
diff --git a/src/libANGLE/capture/FrameCapture.cpp b/src/libANGLE/capture/FrameCapture.cpp
index 22daf186f7..3d9680aa94 100644
--- a/src/libANGLE/capture/FrameCapture.cpp
+++ b/src/libANGLE/capture/FrameCapture.cpp
@@ -4125,7 +4125,7 @@ void CaptureShareGroupMidExecutionSetup(
 
     // Capture Buffer data.
     const gl::BufferManager &buffers = apiState.getBufferManagerForCapture();
-    for (const auto &bufferIter : buffers)
+    for (const auto &bufferIter : gl::UnsafeResourceMapIter(buffers.getResourcesForCapture()))
     {
         gl::BufferID id    = {bufferIter.first};
         gl::Buffer *buffer = bufferIter.second;
@@ -4267,7 +4267,7 @@ void CaptureShareGroupMidExecutionSetup(
     // Capture Texture setup and data.
     const gl::TextureManager &textures = apiState.getTextureManagerForCapture();
 
-    for (const auto &textureIter : textures)
+    for (const auto &textureIter : gl::UnsafeResourceMapIter(textures.getResourcesForCapture()))
     {
         gl::TextureID id     = {textureIter.first};
         gl::Texture *texture = textureIter.second;
@@ -4593,7 +4593,8 @@ void CaptureShareGroupMidExecutionSetup(
     const gl::RenderbufferManager &renderbuffers = apiState.getRenderbufferManagerForCapture();
     FramebufferCaptureFuncs framebufferFuncs(context->isGLES1());
 
-    for (const auto &renderbufIter : renderbuffers)
+    for (const auto &renderbufIter :
+         gl::UnsafeResourceMapIter(renderbuffers.getResourcesForCapture()))
     {
         gl::RenderbufferID id                = {renderbufIter.first};
         const gl::Renderbuffer *renderbuffer = renderbufIter.second;
@@ -4657,7 +4658,7 @@ void CaptureShareGroupMidExecutionSetup(
     // Capture Program binary state.
     gl::ShaderProgramID tempShaderStartID = {resourceTracker->getMaxShaderPrograms()};
     std::map<gl::ShaderProgramID, std::vector<gl::ShaderProgramID>> deferredAttachCalls;
-    for (const auto &programIter : programs)
+    for (const auto &programIter : gl::UnsafeResourceMapIter(programs))
     {
         gl::ShaderProgramID id = {programIter.first};
         gl::Program *program   = programIter.second;
@@ -4738,7 +4739,7 @@ void CaptureShareGroupMidExecutionSetup(
     }
 
     // Handle shaders.
-    for (const auto &shaderIter : shaders)
+    for (const auto &shaderIter : gl::UnsafeResourceMapIter(shaders))
     {
         gl::ShaderProgramID id = {shaderIter.first};
         gl::Shader *shader     = shaderIter.second;
@@ -4827,7 +4828,7 @@ void CaptureShareGroupMidExecutionSetup(
 
     // Capture Sampler Objects
     const gl::SamplerManager &samplers = apiState.getSamplerManagerForCapture();
-    for (const auto &samplerIter : samplers)
+    for (const auto &samplerIter : gl::UnsafeResourceMapIter(samplers.getResourcesForCapture()))
     {
         gl::SamplerID samplerID = {samplerIter.first};
 
@@ -4892,7 +4893,7 @@ void CaptureShareGroupMidExecutionSetup(
 
     // Capture Sync Objects
     const gl::SyncManager &syncs = apiState.getSyncManagerForCapture();
-    for (const auto &syncIter : syncs)
+    for (const auto &syncIter : gl::UnsafeResourceMapIter(syncs.getResourcesForCapture()))
     {
         gl::SyncID syncID    = {syncIter.first};
         const gl::Sync *sync = syncIter.second;
@@ -4967,7 +4968,7 @@ void CaptureMidExecutionSetup(const gl::Context *context,
 
     const gl::VertexArrayMap &vertexArrayMap = context->getVertexArraysForCapture();
     gl::VertexArrayID boundVertexArrayID     = {0};
-    for (const auto &vertexArrayIter : vertexArrayMap)
+    for (const auto &vertexArrayIter : gl::UnsafeResourceMapIter(vertexArrayMap))
     {
         TrackedResource &trackedVertexArrays =
             resourceTracker->getTrackedResource(context->id(), ResourceIDType::VertexArray);
@@ -5145,7 +5146,8 @@ void CaptureMidExecutionSetup(const gl::Context *context,
 
     const gl::RenderbufferManager &renderbuffers = apiState.getRenderbufferManagerForCapture();
     gl::RenderbufferID currentRenderbuffer       = {0};
-    for (const auto &renderbufIter : renderbuffers)
+    for (const auto &renderbufIter :
+         gl::UnsafeResourceMapIter(renderbuffers.getResourcesForCapture()))
     {
         currentRenderbuffer = renderbufIter.second->id();
     }
@@ -5162,7 +5164,8 @@ void CaptureMidExecutionSetup(const gl::Context *context,
     gl::FramebufferID currentDrawFramebuffer = {0};
     gl::FramebufferID currentReadFramebuffer = {0};
 
-    for (const auto &framebufferIter : framebuffers)
+    for (const auto &framebufferIter :
+         gl::UnsafeResourceMapIter(framebuffers.getResourcesForCapture()))
     {
         gl::FramebufferID id               = {framebufferIter.first};
         const gl::Framebuffer *framebuffer = framebufferIter.second;
@@ -5297,7 +5300,8 @@ void CaptureMidExecutionSetup(const gl::Context *context,
     const gl::ProgramPipelineManager *programPipelineManager =
         apiState.getProgramPipelineManagerForCapture();
 
-    for (const auto &ppoIterator : *programPipelineManager)
+    for (const auto &ppoIterator :
+         gl::UnsafeResourceMapIter(programPipelineManager->getResourcesForCapture()))
     {
         gl::ProgramPipeline *pipeline = ppoIterator.second;
         gl::ProgramPipelineID id      = {ppoIterator.first};
@@ -5380,8 +5384,9 @@ void CaptureMidExecutionSetup(const gl::Context *context,
     // Create existing queries. Note that queries may be genned and not yet started. In that
     // case the queries will exist in the query map as nullptr entries.
     const gl::QueryMap &queryMap = context->getQueriesForCapture();
-    for (gl::QueryMap::Iterator queryIter = queryMap.beginWithNull();
-         queryIter != queryMap.endWithNull(); ++queryIter)
+    for (gl::QueryMap::Iterator queryIter = gl::UnsafeResourceMapIter(queryMap).beginWithNull(),
+                                endIter   = gl::UnsafeResourceMapIter(queryMap).endWithNull();
+         queryIter != endIter; ++queryIter)
     {
         ASSERT(queryIter->first);
         gl::QueryID queryID = {queryIter->first};
@@ -5407,7 +5412,7 @@ void CaptureMidExecutionSetup(const gl::Context *context,
 
     // Transform Feedback
     const gl::TransformFeedbackMap &xfbMap = context->getTransformFeedbacksForCapture();
-    for (const auto &xfbIter : xfbMap)
+    for (const auto &xfbIter : gl::UnsafeResourceMapIter(xfbMap))
     {
         gl::TransformFeedbackID xfbID = {xfbIter.first};
 
diff --git a/src/libANGLE/capture/serialize.cpp b/src/libANGLE/capture/serialize.cpp
index c1138a7f34..61655020a6 100644
--- a/src/libANGLE/capture/serialize.cpp
+++ b/src/libANGLE/capture/serialize.cpp
@@ -1404,7 +1404,8 @@ Result SerializeContextToString(const gl::Context *context, std::string *stringO
         const gl::FramebufferManager &framebufferManager =
             context->getState().getFramebufferManagerForCapture();
         GroupScope framebufferGroup(&json, "FramebufferManager");
-        for (const auto &framebuffer : framebufferManager)
+        for (const auto &framebuffer :
+             gl::UnsafeResourceMapIter(framebufferManager.getResourcesForCapture()))
         {
             gl::Framebuffer *framebufferPtr = framebuffer.second;
             ANGLE_TRY(SerializeFramebuffer(context, &json, &scratchBuffer, framebufferPtr));
@@ -1413,7 +1414,7 @@ Result SerializeContextToString(const gl::Context *context, std::string *stringO
     {
         const gl::BufferManager &bufferManager = context->getState().getBufferManagerForCapture();
         GroupScope framebufferGroup(&json, "BufferManager");
-        for (const auto &buffer : bufferManager)
+        for (const auto &buffer : gl::UnsafeResourceMapIter(bufferManager.getResourcesForCapture()))
         {
             gl::Buffer *bufferPtr = buffer.second;
             ANGLE_TRY(SerializeBuffer(context, &json, &scratchBuffer, bufferPtr));
@@ -1423,7 +1424,8 @@ Result SerializeContextToString(const gl::Context *context, std::string *stringO
         const gl::SamplerManager &samplerManager =
             context->getState().getSamplerManagerForCapture();
         GroupScope samplerGroup(&json, "SamplerManager");
-        for (const auto &sampler : samplerManager)
+        for (const auto &sampler :
+             gl::UnsafeResourceMapIter(samplerManager.getResourcesForCapture()))
         {
             gl::Sampler *samplerPtr = sampler.second;
             SerializeSampler(&json, samplerPtr);
@@ -1433,7 +1435,8 @@ Result SerializeContextToString(const gl::Context *context, std::string *stringO
         const gl::RenderbufferManager &renderbufferManager =
             context->getState().getRenderbufferManagerForCapture();
         GroupScope renderbufferGroup(&json, "RenderbufferManager");
-        for (const auto &renderbuffer : renderbufferManager)
+        for (const auto &renderbuffer :
+             gl::UnsafeResourceMapIter(renderbufferManager.getResourcesForCapture()))
         {
             gl::Renderbuffer *renderbufferPtr = renderbuffer.second;
             ANGLE_TRY(SerializeRenderbuffer(context, &json, &scratchBuffer, renderbufferPtr));
@@ -1445,7 +1448,7 @@ Result SerializeContextToString(const gl::Context *context, std::string *stringO
         const gl::ResourceMap<gl::Shader, gl::ShaderProgramID> &shaderManager =
             shaderProgramManager.getShadersForCapture();
         GroupScope shaderGroup(&json, "ShaderManager");
-        for (const auto &shader : shaderManager)
+        for (const auto &shader : gl::UnsafeResourceMapIter(shaderManager))
         {
             GLuint id             = shader.first;
             gl::Shader *shaderPtr = shader.second;
@@ -1456,7 +1459,7 @@ Result SerializeContextToString(const gl::Context *context, std::string *stringO
         const gl::ResourceMap<gl::Program, gl::ShaderProgramID> &programManager =
             shaderProgramManager.getProgramsForCaptureAndPerf();
         GroupScope shaderGroup(&json, "ProgramManager");
-        for (const auto &program : programManager)
+        for (const auto &program : gl::UnsafeResourceMapIter(programManager))
         {
             GLuint id               = program.first;
             gl::Program *programPtr = program.second;
@@ -1467,7 +1470,8 @@ Result SerializeContextToString(const gl::Context *context, std::string *stringO
         const gl::TextureManager &textureManager =
             context->getState().getTextureManagerForCapture();
         GroupScope shaderGroup(&json, "TextureManager");
-        for (const auto &texture : textureManager)
+        for (const auto &texture :
+             gl::UnsafeResourceMapIter(textureManager.getResourcesForCapture()))
         {
             gl::Texture *texturePtr = texture.second;
             ANGLE_TRY(SerializeTexture(context, &json, &scratchBuffer, texturePtr));
@@ -1476,7 +1480,7 @@ Result SerializeContextToString(const gl::Context *context, std::string *stringO
     {
         const gl::VertexArrayMap &vertexArrayMap = context->getVertexArraysForCapture();
         GroupScope shaderGroup(&json, "VertexArrayMap");
-        for (const auto &vertexArray : vertexArrayMap)
+        for (const auto &vertexArray : gl::UnsafeResourceMapIter(vertexArrayMap))
         {
             gl::VertexArray *vertexArrayPtr = vertexArray.second;
             SerializeVertexArray(&json, vertexArrayPtr);