Add m-esr52 at 52.6.0

1 files changed, 928 insertions, 0 deletions

diff --git a/gfx/gl/GLContextFeatures.cpp b/gfx/gl/GLContextFeatures.cpp
new file mode 100644
index 000000000..0714d9641
--- /dev/null
+++ b/gfx/gl/GLContextFeatures.cpp
@@ -0,0 +1,928 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "GLContext.h"
+#include "nsPrintfCString.h"
+
+namespace mozilla {
+namespace gl {
+
+const size_t kMAX_EXTENSION_GROUP_SIZE = 5;
+
+enum class GLVersion : uint32_t {
+    NONE  = 0,   // Feature is not supported natively by GL
+    GL1_2 = 120,
+    GL1_3 = 130,
+    GL2   = 200,
+    GL2_1 = 210,
+    GL3   = 300,
+    GL3_1 = 310,
+    GL3_2 = 320,
+    GL3_3 = 330,
+    GL4   = 400,
+    GL4_1 = 410,
+    GL4_2 = 420,
+    GL4_3 = 430,
+};
+
+enum class GLESVersion : uint32_t {
+    NONE  = 0,   // Feature is not support natively by GL ES
+    ES2   = 200,
+    ES3   = 300,
+    ES3_1 = 310,
+    ES3_2 = 320,
+};
+
+// ARB_ES2_compatibility is natively supported in OpenGL 4.1.
+static const GLVersion kGLCoreVersionForES2Compat = GLVersion::GL4_1;
+
+// ARB_ES3_compatibility is natively supported in OpenGL 4.3.
+static const GLVersion kGLCoreVersionForES3Compat = GLVersion::GL4_3;
+
+struct FeatureInfo
+{
+    const char* mName;
+
+    /* The (desktop) OpenGL version that provides this feature */
+    GLVersion mOpenGLVersion;
+
+    /* The OpenGL ES version that provides this feature */
+    GLESVersion mOpenGLESVersion;
+
+    /* If there is an ARB extension, and its function symbols are
+     * not decorated with an ARB suffix, then its extension ID should go
+     * here, and NOT in mExtensions.  For example, ARB_vertex_array_object
+     * functions do not have an ARB suffix, because it is an extension that
+     * was created to match core GL functionality and will never differ.
+     * Some ARB extensions do have a suffix, if they were created before
+     * a core version of the functionality existed.
+     *
+     * If there is no such ARB extension, pass 0 (GLContext::Extension_None)
+     */
+    GLContext::GLExtensions mARBExtensionWithoutARBSuffix;
+
+    /* Extensions that also provide this feature */
+    GLContext::GLExtensions mExtensions[kMAX_EXTENSION_GROUP_SIZE];
+};
+
+static const FeatureInfo sFeatureInfoArr[] = {
+    {
+        "bind_buffer_offset",
+        GLVersion::NONE,
+        GLESVersion::NONE,
+        GLContext::Extension_None,
+        {
+
+            GLContext::EXT_transform_feedback,
+            GLContext::NV_transform_feedback2,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "blend_minmax",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_blend_minmax,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "clear_buffers",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "copy_buffer",
+        GLVersion::GL3_1,
+        GLESVersion::ES3,
+        GLContext::ARB_copy_buffer,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "depth_texture",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_depth_texture,
+            GLContext::OES_depth_texture,
+            // Intentionally avoid putting ANGLE_depth_texture here,
+            // it does not offer quite the same functionality.
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "draw_buffers",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_draw_buffers,
+            GLContext::EXT_draw_buffers,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "draw_instanced",
+        GLVersion::GL3_1,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_draw_instanced,
+            GLContext::EXT_draw_instanced,
+            GLContext::NV_draw_instanced,
+            GLContext::ANGLE_instanced_arrays,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "draw_range_elements",
+        GLVersion::GL1_2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_draw_range_elements,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "element_index_uint",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::OES_element_index_uint,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "ES2_compatibility",
+        kGLCoreVersionForES2Compat,
+        GLESVersion::ES2, // OpenGL ES version
+        GLContext::ARB_ES2_compatibility, // no suffix on ARB extension
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "ES3_compatibility",
+        kGLCoreVersionForES3Compat,
+        GLESVersion::ES3, // OpenGL ES version
+        GLContext::ARB_ES3_compatibility, // no suffix on ARB extension
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "EXT_color_buffer_float",
+        GLVersion::GL3,
+        GLESVersion::ES3_2,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_color_buffer_float,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        // Removes clamping for float color outputs from frag shaders.
+        "frag_color_float",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_color_buffer_float,
+            GLContext::EXT_color_buffer_float,
+            GLContext::EXT_color_buffer_half_float,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "frag_depth",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_frag_depth,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        // Check for just the blit framebuffer blit part of
+        // ARB_framebuffer_object
+        "framebuffer_blit",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::ARB_framebuffer_object,
+        {
+            GLContext::ANGLE_framebuffer_blit,
+            GLContext::EXT_framebuffer_blit,
+            GLContext::NV_framebuffer_blit,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        // Check for just the multisample renderbuffer part of
+        // ARB_framebuffer_object
+        "framebuffer_multisample",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::ARB_framebuffer_object,
+        {
+            GLContext::ANGLE_framebuffer_multisample,
+            GLContext::APPLE_framebuffer_multisample,
+            GLContext::EXT_framebuffer_multisample,
+            GLContext::EXT_multisampled_render_to_texture,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        // ARB_framebuffer_object support
+        "framebuffer_object",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::ARB_framebuffer_object,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        // EXT_framebuffer_object/OES_framebuffer_object support
+        "framebuffer_object_EXT_OES",
+        GLVersion::GL3,
+        GLESVersion::ES2,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_framebuffer_object,
+            GLContext::OES_framebuffer_object,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "get_integer_indexed",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_draw_buffers2,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "get_integer64_indexed",
+        GLVersion::GL3_2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "get_query_object_i64v",
+        GLVersion::GL3_3,
+        GLESVersion::NONE,
+        GLContext::ARB_timer_query,
+        {
+            GLContext::ANGLE_timer_query,
+            GLContext::EXT_disjoint_timer_query,
+            GLContext::EXT_timer_query,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "get_query_object_iv",
+        GLVersion::GL2,
+        GLESVersion::NONE,
+        GLContext::Extension_None,
+        {
+            GLContext::Extensions_End
+        }
+        /*
+         * XXX_get_query_object_iv only provide GetQueryObjectiv provided by
+         * ARB_occlusion_query (added by OpenGL 2.0).
+         */
+    },
+    {
+        "get_string_indexed",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::Extensions_End
+        }
+        // glGetStringi
+    },
+    {
+        "gpu_shader4",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_gpu_shader4,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "instanced_arrays",
+        GLVersion::GL3_3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_instanced_arrays,
+            GLContext::NV_instanced_arrays,
+            GLContext::ANGLE_instanced_arrays,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "instanced_non_arrays",
+        GLVersion::GL3_3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_instanced_arrays,
+            GLContext::Extensions_End
+        }
+        /* This is an expanded version of `instanced_arrays` that allows for all
+         * enabled active attrib arrays to have non-zero divisors.
+         * ANGLE_instanced_arrays and NV_instanced_arrays forbid this, but GLES3
+         * has no such restriction.
+         */
+    },
+    {
+        "internalformat_query",
+        GLVersion::GL4_2,
+        GLESVersion::ES3,
+        GLContext::ARB_internalformat_query,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "invalidate_framebuffer",
+        GLVersion::GL4_3,
+        GLESVersion::ES3,
+        GLContext::ARB_invalidate_subdata,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "map_buffer_range",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::ARB_map_buffer_range,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "occlusion_query",
+        GLVersion::GL2,
+        GLESVersion::NONE,
+        GLContext::Extension_None,
+        {
+            GLContext::Extensions_End
+        }
+        // XXX_occlusion_query depend on ARB_occlusion_query (added in OpenGL 2.0)
+    },
+    {
+        "occlusion_query_boolean",
+        kGLCoreVersionForES3Compat,
+        GLESVersion::ES3,
+        GLContext::ARB_ES3_compatibility,
+        {
+            GLContext::EXT_occlusion_query_boolean,
+            GLContext::Extensions_End
+        }
+        /*
+         * XXX_occlusion_query_boolean provide ANY_SAMPLES_PASSED_CONSERVATIVE,
+         * but EXT_occlusion_query_boolean is only a OpenGL ES extension. But
+         * it is supported on desktop if ARB_ES3_compatibility because
+         * EXT_occlusion_query_boolean (added in OpenGL ES 3.0).
+         */
+    },
+    {
+        "occlusion_query2",
+        GLVersion::GL3_3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_occlusion_query2,
+            GLContext::ARB_ES3_compatibility,
+            GLContext::EXT_occlusion_query_boolean,
+            GLContext::Extensions_End
+        }
+        /*
+         * XXX_occlusion_query2 (add in OpenGL 3.3) provide ANY_SAMPLES_PASSED,
+         * which is provided by ARB_occlusion_query2, EXT_occlusion_query_boolean
+         * (added in OpenGL ES 3.0) and ARB_ES3_compatibility
+         */
+    },
+    {
+        "packed_depth_stencil",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_packed_depth_stencil,
+            GLContext::OES_packed_depth_stencil,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "prim_restart",
+        GLVersion::GL3_1,
+        GLESVersion::NONE,
+        GLContext::Extension_None,
+        {
+            //GLContext::NV_primitive_restart, // Has different enum values.
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "prim_restart_fixed",
+        kGLCoreVersionForES3Compat,
+        GLESVersion::ES3,
+        GLContext::ARB_ES3_compatibility,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "query_counter",
+        GLVersion::GL3_3,
+        GLESVersion::NONE,
+        GLContext::ARB_timer_query,
+        {
+            GLContext::ANGLE_timer_query,
+            GLContext::EXT_disjoint_timer_query,
+            // EXT_timer_query does NOT support GL_TIMESTAMP retrieval with
+            // QueryCounter.
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "query_objects",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ANGLE_timer_query,
+            GLContext::EXT_disjoint_timer_query,
+            GLContext::EXT_occlusion_query_boolean,
+            GLContext::Extensions_End
+        }
+        /*
+         * XXX_query_objects only provide entry points commonly supported by
+         * ARB_occlusion_query (added in OpenGL 2.0), EXT_occlusion_query_boolean
+         * (added in OpenGL ES 3.0), and ARB_timer_query (added in OpenGL 3.3)
+         */
+    },
+    {
+        "query_time_elapsed",
+        GLVersion::GL3_3,
+        GLESVersion::NONE,
+        GLContext::ARB_timer_query,
+        {
+            GLContext::ANGLE_timer_query,
+            GLContext::EXT_disjoint_timer_query,
+            GLContext::EXT_timer_query,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "read_buffer",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "renderbuffer_color_float",
+        GLVersion::GL3,
+        GLESVersion::ES3_2,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_texture_float,
+            GLContext::EXT_color_buffer_float,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "renderbuffer_color_half_float",
+        GLVersion::GL3,
+        GLESVersion::ES3_2,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_texture_float,
+            GLContext::EXT_color_buffer_float,
+            GLContext::EXT_color_buffer_half_float,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "robustness",
+        GLVersion::NONE,
+        GLESVersion::NONE,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_robustness,
+            GLContext::EXT_robustness,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "sRGB_framebuffer",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::ARB_framebuffer_sRGB,
+        {
+            GLContext::EXT_framebuffer_sRGB,
+            GLContext::EXT_sRGB_write_control,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "sRGB_texture",
+        GLVersion::GL2_1,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_sRGB,
+            GLContext::EXT_texture_sRGB,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "sampler_objects",
+        GLVersion::GL3_3,
+        GLESVersion::ES3,
+        GLContext::ARB_sampler_objects,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "seamless_cube_map_opt_in",
+        GLVersion::GL3_2,
+        GLESVersion::NONE,
+        GLContext::ARB_seamless_cube_map,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "shader_texture_lod",
+        GLVersion::NONE,
+        GLESVersion::NONE,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_shader_texture_lod,
+            GLContext::EXT_shader_texture_lod,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        // Do we have separate DRAW and READ framebuffer bind points?
+        "split_framebuffer",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::ARB_framebuffer_object,
+        {
+            GLContext::ANGLE_framebuffer_blit,
+            GLContext::APPLE_framebuffer_multisample,
+            GLContext::EXT_framebuffer_blit,
+            GLContext::NV_framebuffer_blit,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "standard_derivatives",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::OES_standard_derivatives,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "sync",
+        GLVersion::GL3_2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_sync,
+            GLContext::APPLE_sync,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_3D",
+        GLVersion::GL1_2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_texture3D,
+            GLContext::OES_texture_3D,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_3D_compressed",
+        GLVersion::GL1_3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_texture_compression,
+            GLContext::OES_texture_3D,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_3D_copy",
+        GLVersion::GL1_2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::EXT_copy_texture,
+            GLContext::OES_texture_3D,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_float",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_texture_float,
+            GLContext::OES_texture_float,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_float_linear",
+        GLVersion::GL3_1,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_texture_float,
+            GLContext::OES_texture_float_linear,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_half_float",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_half_float_pixel,
+            GLContext::ARB_texture_float,
+            GLContext::NV_half_float,
+            GLContext::Extensions_End
+        }
+        /**
+         * We are not including OES_texture_half_float in this feature, because:
+         *   GL_HALF_FLOAT     = 0x140B
+         *   GL_HALF_FLOAT_ARB = 0x140B == GL_HALF_FLOAT
+         *   GL_HALF_FLOAT_NV  = 0x140B == GL_HALF_FLOAT
+         *   GL_HALF_FLOAT_OES = 0x8D61 != GL_HALF_FLOAT
+         * WebGL handles this specifically with an OES_texture_half_float check.
+         */
+    },
+    {
+        "texture_half_float_linear",
+        GLVersion::GL3_1,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_half_float_pixel,
+            GLContext::ARB_texture_float,
+            GLContext::NV_half_float,
+            GLContext::OES_texture_half_float_linear,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_non_power_of_two",
+        GLVersion::GL2,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::ARB_texture_non_power_of_two,
+            GLContext::OES_texture_npot,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_rg",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::ARB_texture_rg,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_storage",
+        GLVersion::GL4_2,
+        GLESVersion::ES3,
+        GLContext::ARB_texture_storage,
+        {
+            /*
+             * Not including GL_EXT_texture_storage here because it
+             * doesn't guarantee glTexStorage3D, which is required for
+             * WebGL 2.
+             */
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "texture_swizzle",
+        GLVersion::GL3_3,
+        GLESVersion::ES3,
+        GLContext::ARB_texture_swizzle,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "transform_feedback2",
+        GLVersion::GL4,
+        GLESVersion::ES3,
+        GLContext::ARB_transform_feedback2,
+        {
+            GLContext::NV_transform_feedback2,
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "uniform_buffer_object",
+        GLVersion::GL3_1,
+        GLESVersion::ES3,
+        GLContext::ARB_uniform_buffer_object,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "uniform_matrix_nonsquare",
+        GLVersion::GL2_1,
+        GLESVersion::ES3,
+        GLContext::Extension_None,
+        {
+            GLContext::Extensions_End
+        }
+    },
+    {
+        "vertex_array_object",
+        GLVersion::GL3,
+        GLESVersion::ES3,
+        GLContext::ARB_vertex_array_object, // ARB extension
+        {
+            GLContext::OES_vertex_array_object,
+            GLContext::APPLE_vertex_array_object,
+            GLContext::Extensions_End
+        }
+    }
+};
+
+static inline const FeatureInfo&
+GetFeatureInfo(GLFeature feature)
+{
+    static_assert(MOZ_ARRAY_LENGTH(sFeatureInfoArr) == size_t(GLFeature::EnumMax),
+                  "Mismatched lengths for sFeatureInfoInfos and GLFeature enums");
+
+    MOZ_ASSERT(feature < GLFeature::EnumMax,
+               "GLContext::GetFeatureInfoInfo : unknown <feature>");
+
+    return sFeatureInfoArr[size_t(feature)];
+}
+
+static inline uint32_t
+ProfileVersionForFeature(GLFeature feature, ContextProfile profile)
+{
+    MOZ_ASSERT(profile != ContextProfile::Unknown,
+               "GLContext::ProfileVersionForFeature : unknown <profile>");
+
+    const FeatureInfo& featureInfo = GetFeatureInfo(feature);
+
+    if (profile == ContextProfile::OpenGLES)
+        return (uint32_t)featureInfo.mOpenGLESVersion;
+
+    return (uint32_t)featureInfo.mOpenGLVersion;
+}
+
+bool
+IsFeaturePartOfProfileVersion(GLFeature feature,
+                              ContextProfile profile, unsigned int version)
+{
+    unsigned int profileVersion = ProfileVersionForFeature(feature, profile);
+
+    /**
+     * if `profileVersion` is zero, it means that no version of the profile
+     * added support for the feature.
+     */
+    return profileVersion && version >= profileVersion;
+}
+
+bool
+GLContext::IsFeatureProvidedByCoreSymbols(GLFeature feature)
+{
+    if (IsFeaturePartOfProfileVersion(feature, mProfile, mVersion))
+        return true;
+
+    if (IsExtensionSupported(GetFeatureInfo(feature).mARBExtensionWithoutARBSuffix))
+        return true;
+
+    return false;
+}
+
+const char*
+GLContext::GetFeatureName(GLFeature feature)
+{
+    return GetFeatureInfo(feature).mName;
+}
+
+void
+GLContext::InitFeatures()
+{
+    for (size_t featureId = 0; featureId < size_t(GLFeature::EnumMax); featureId++) {
+        GLFeature feature = GLFeature(featureId);
+
+        if (IsFeaturePartOfProfileVersion(feature, mProfile, mVersion)) {
+            mAvailableFeatures[featureId] = true;
+            continue;
+        }
+
+        mAvailableFeatures[featureId] = false;
+
+        const FeatureInfo& featureInfo = GetFeatureInfo(feature);
+
+        if (IsExtensionSupported(featureInfo.mARBExtensionWithoutARBSuffix)) {
+            mAvailableFeatures[featureId] = true;
+            continue;
+        }
+
+        for (size_t j = 0; true; j++) {
+            MOZ_ASSERT(j < kMAX_EXTENSION_GROUP_SIZE,
+                       "kMAX_EXTENSION_GROUP_SIZE too small");
+
+            if (featureInfo.mExtensions[j] == GLContext::Extensions_End)
+                break;
+
+            if (IsExtensionSupported(featureInfo.mExtensions[j])) {
+                mAvailableFeatures[featureId] = true;
+                break;
+            }
+        }
+    }
+
+    if (ShouldDumpExts()) {
+        for (size_t featureId = 0; featureId < size_t(GLFeature::EnumMax); featureId++) {
+            GLFeature feature = GLFeature(featureId);
+            printf_stderr("[%s] Feature::%s\n",
+                          IsSupported(feature) ? "enabled" : "disabled",
+                          GetFeatureName(feature));
+        }
+    }
+}
+
+void
+GLContext::MarkUnsupported(GLFeature feature)
+{
+    mAvailableFeatures[size_t(feature)] = false;
+
+    const FeatureInfo& featureInfo = GetFeatureInfo(feature);
+
+    for (size_t i = 0; true; i++) {
+        MOZ_ASSERT(i < kMAX_EXTENSION_GROUP_SIZE, "kMAX_EXTENSION_GROUP_SIZE too small");
+
+        if (featureInfo.mExtensions[i] == GLContext::Extensions_End)
+            break;
+
+        MarkExtensionUnsupported(featureInfo.mExtensions[i]);
+    }
+
+    MOZ_ASSERT(!IsSupported(feature), "GLContext::MarkUnsupported has failed!");
+
+    NS_WARNING(nsPrintfCString("%s marked as unsupported",
+                               GetFeatureName(feature)).get());
+}
+
+} /* namespace gl */
+} /* namespace mozilla */