GL: avoid populating and sorting (!!) a vector of strings for exts.

Ew. At first I tried to just port a growable Array of StringViews (which would already save quite a lot), but then I realized I have a clear upper bound on the extensions and so can use a "counting sort" without having to deduplicate anything after. After the previous (rather minimal) reduction by the Context cleanup, this reduces the size of magnum-gl-info.wasm from 245 to 237 kB. Quite significant, I'd say!
mosra · Mar 3, 2021 · e96996e · e96996e
1 parent 32a7ade
commit e96996e
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Showing 25 changed files with 242 additions and 163 deletions.
diff --git a/src/Magnum/GL/Context.h b/src/Magnum/GL/Context.h
@@ -57,17 +57,6 @@ namespace GL {
 namespace Implementation {
     struct ContextState;
     struct State;
-
-    enum: std::size_t {
-        ExtensionCount =
-            #ifndef MAGNUM_TARGET_GLES
-            192
-            #elif !defined(MAGNUM_TARGET_WEBGL)
-            160
-            #else
-            48
-            #endif
-    };
 }
 
 /**

diff --git a/src/Magnum/GL/GL.h b/src/Magnum/GL/GL.h
@@ -29,6 +29,8 @@
  * @brief Forward declarations for the @ref Magnum::GL namespace
  */
 
+#include <cstddef>
+
 #include "Magnum/Types.h"
 
 #ifndef DOXYGEN_GENERATING_OUTPUT
@@ -40,6 +42,20 @@ typedef unsigned int GLuint; /* Needed by Implementation/State.h */
 namespace Magnum { namespace GL {
 
 #ifndef DOXYGEN_GENERATING_OUTPUT
+namespace Implementation {
+    /* Needed by Context as well as all Implementation::*State classes */
+    enum: std::size_t {
+        ExtensionCount =
+            #ifndef MAGNUM_TARGET_GLES
+            192
+            #elif !defined(MAGNUM_TARGET_WEBGL)
+            160
+            #else
+            48
+            #endif
+    };
+}
+
 /* FramebufferClear[Mask], FramebufferBlit[Mask], FramebufferBlitFilter,
    FramebufferTarget enums used only directly with framebuffer instance */
 class AbstractFramebuffer;

diff --git a/src/Magnum/GL/Implementation/BufferState.cpp b/src/Magnum/GL/Implementation/BufferState.cpp
@@ -80,7 +80,7 @@ std::size_t BufferState::indexForTarget(Buffer::TargetHint target) {
     CORRADE_INTERNAL_ASSERT_UNREACHABLE(); /* LCOV_EXCL_LINE */
 }
 
-BufferState::BufferState(Context& context, std::vector<std::string>& extensions): bindings()
+BufferState::BufferState(Context& context, Containers::StaticArrayView<Implementation::ExtensionCount, const char*> extensions): bindings()
     #ifndef MAGNUM_TARGET_GLES2
     #ifndef MAGNUM_TARGET_GLES
     , minMapAlignment(0)
@@ -99,7 +99,8 @@ BufferState::BufferState(Context& context, std::vector<std::string>& extensions)
         context.isDriverWorkaroundDisabled("intel-windows-crazy-broken-buffer-dsa"_s))
         #endif
     ) {
-        extensions.emplace_back(Extensions::ARB::direct_state_access::string());
+        extensions[Extensions::ARB::direct_state_access::Index] =
+                   Extensions::ARB::direct_state_access::string();
 
         createImplementation = &Buffer::createImplementationDSA;
         copyImplementation = &Buffer::copyImplementationDSA;
@@ -140,7 +141,8 @@ BufferState::BufferState(Context& context, std::vector<std::string>& extensions)
 
     #ifndef MAGNUM_TARGET_GLES
     if(context.isExtensionSupported<Extensions::ARB::invalidate_subdata>()) {
-        extensions.emplace_back(Extensions::ARB::invalidate_subdata::string());
+        extensions[Extensions::ARB::invalidate_subdata::Index] =
+                   Extensions::ARB::invalidate_subdata::string();
 
         invalidateImplementation = &Buffer::invalidateImplementationARB;
         invalidateSubImplementation = &Buffer::invalidateSubImplementationARB;
@@ -154,7 +156,8 @@ BufferState::BufferState(Context& context, std::vector<std::string>& extensions)
     #ifndef MAGNUM_TARGET_GLES2
     #ifndef MAGNUM_TARGET_GLES
     if(context.isExtensionSupported<Extensions::ARB::multi_bind>()) {
-        extensions.emplace_back(Extensions::ARB::multi_bind::string());
+        extensions[Extensions::ARB::multi_bind::Index] =
+                   Extensions::ARB::multi_bind::string();
 
         bindBasesImplementation = &Buffer::bindImplementationMulti;
         bindRangesImplementation = &Buffer::bindImplementationMulti;

diff --git a/src/Magnum/GL/Implementation/BufferState.h b/src/Magnum/GL/Implementation/BufferState.h
@@ -25,8 +25,6 @@
     DEALINGS IN THE SOFTWARE.
 */
 
-#include <vector>
-
 #include "Magnum/GL/Buffer.h"
 
 namespace Magnum { namespace GL { namespace Implementation {
@@ -46,7 +44,7 @@ struct BufferState {
     static std::size_t indexForTarget(Buffer::TargetHint target);
     static const Buffer::TargetHint targetForIndex[TargetCount-1];
 
-    explicit BufferState(Context& context, std::vector<std::string>& extensions);
+    explicit BufferState(Context& context, Containers::StaticArrayView<Implementation::ExtensionCount, const char*> extensions);
 
     void reset();
 

diff --git a/src/Magnum/GL/Implementation/ContextState.cpp b/src/Magnum/GL/Implementation/ContextState.cpp
@@ -33,7 +33,7 @@ namespace Magnum { namespace GL { namespace Implementation {
 
 using namespace Containers::Literals;
 
-ContextState::ContextState(Context& context, std::vector<std::string>&) {
+ContextState::ContextState(Context& context, Containers::StaticArrayView<Implementation::ExtensionCount, const char*>) {
     #ifndef MAGNUM_TARGET_GLES
     if((context.detectedDriver() & Context::DetectedDriver::NVidia) &&
         !context.isDriverWorkaroundDisabled("nv-zero-context-profile-mask"_s))

diff --git a/src/Magnum/GL/Implementation/ContextState.h b/src/Magnum/GL/Implementation/ContextState.h
@@ -25,9 +25,7 @@
     DEALINGS IN THE SOFTWARE.
 */
 
-#include <string>
-#include <vector>
-
+#include "Magnum/Magnum.h"
 #include "Magnum/GL/GL.h"
 
 #ifdef _MSC_VER
@@ -40,7 +38,7 @@
 namespace Magnum { namespace GL { namespace Implementation {
 
 struct ContextState {
-    explicit ContextState(Context& context, std::vector<std::string>& extensions);
+    explicit ContextState(Context& context, Containers::StaticArrayView<Implementation::ExtensionCount, const char*> extensions);
 
     #ifndef MAGNUM_TARGET_GLES
     enum class CoreProfile {

diff --git a/src/Magnum/GL/Implementation/DebugState.cpp b/src/Magnum/GL/Implementation/DebugState.cpp
@@ -31,7 +31,7 @@
 
 namespace Magnum { namespace GL { namespace Implementation {
 
-DebugState::DebugState(Context& context, std::vector<std::string>& extensions):
+DebugState::DebugState(Context& context, Containers::StaticArrayView<Implementation::ExtensionCount, const char*> extensions):
     maxLabelLength{0},
     maxLoggedMessages{0},
     maxMessageLength{0},
@@ -45,7 +45,8 @@ DebugState::DebugState(Context& context, std::vector<std::string>& extensions):
     #endif
     {
         #ifndef MAGNUM_TARGET_GLES
-        extensions.emplace_back(Extensions::KHR::debug::string());
+        extensions[Extensions::KHR::debug::Index] =
+                   Extensions::KHR::debug::string();
         #endif
 
         getLabelImplementation = &AbstractObject::getLabelImplementationKhrDesktopES32;
@@ -60,7 +61,8 @@ DebugState::DebugState(Context& context, std::vector<std::string>& extensions):
     #endif
     #ifdef MAGNUM_TARGET_GLES
     if(context.isExtensionSupported<Extensions::KHR::debug>()) {
-        extensions.emplace_back(Extensions::KHR::debug::string());
+        extensions[Extensions::KHR::debug::Index] =
+                   Extensions::KHR::debug::string();
 
         getLabelImplementation = &AbstractObject::getLabelImplementationKhrES;
         labelImplementation = &AbstractObject::labelImplementationKhrES;
@@ -74,7 +76,8 @@ DebugState::DebugState(Context& context, std::vector<std::string>& extensions):
     #endif
     {
         if(context.isExtensionSupported<Extensions::EXT::debug_label>()) {
-            extensions.emplace_back(Extensions::EXT::debug_label::string());
+            extensions[Extensions::EXT::debug_label::Index] =
+                       Extensions::EXT::debug_label::string();
 
             getLabelImplementation = &AbstractObject::getLabelImplementationExt;
             labelImplementation = &AbstractObject::labelImplementationExt;
@@ -84,14 +87,16 @@ DebugState::DebugState(Context& context, std::vector<std::string>& extensions):
         }
 
         if(context.isExtensionSupported<Extensions::EXT::debug_marker>()) {
-            extensions.emplace_back(Extensions::EXT::debug_marker::string());
+            extensions[Extensions::EXT::debug_marker::Index] =
+                       Extensions::EXT::debug_marker::string();
 
             pushGroupImplementation = &DebugGroup::pushImplementationExt;
             popGroupImplementation = &DebugGroup::popImplementationExt;
             messageInsertImplementation = &DebugMessage::insertImplementationExt;
         #ifndef MAGNUM_TARGET_GLES
         } else if(context.isExtensionSupported<Extensions::GREMEDY::string_marker>()) {
-            extensions.emplace_back(Extensions::GREMEDY::string_marker::string());
+            extensions[Extensions::GREMEDY::string_marker::Index] =
+                       Extensions::GREMEDY::string_marker::string();
 
             pushGroupImplementation = &DebugGroup::pushImplementationNoOp;
             popGroupImplementation = &DebugGroup::popImplementationNoOp;

diff --git a/src/Magnum/GL/Implementation/DebugState.h b/src/Magnum/GL/Implementation/DebugState.h
@@ -25,9 +25,6 @@
     DEALINGS IN THE SOFTWARE.
 */
 
-#include <string>
-#include <vector>
-
 #include "Magnum/GL/DebugOutput.h"
 #include "Magnum/GL/GL.h"
 
@@ -38,7 +35,7 @@
 namespace Magnum { namespace GL { namespace Implementation {
 
 struct DebugState {
-    explicit DebugState(Context& context, std::vector<std::string>& extensions);
+    explicit DebugState(Context& context, Containers::StaticArrayView<Implementation::ExtensionCount, const char*> extensions);
 
     std::string(*getLabelImplementation)(GLenum, GLuint);
     void(*labelImplementation)(GLenum, GLuint, Containers::ArrayView<const char>);