Cherry-pick from gles3-dev: Add and implement ANGLE_device_mtl extens…

…ion.

Allow user to query internal MTLDevice used by MetalANGLE.

Change-Id: If310917c091b80ad605084403b94ffee5e803553

# Conflicts:
#	include/EGL/eglext_angle.h
#	src/libANGLE/Caps.h
#	src/libANGLE/renderer/metal/DisplayMtl.mm
#	src/libGLESv2/entry_points_egl_ext.cpp

extensions/EGL_ANGLE_device_mtl.txt

@@ -0,0 +1,90 @@
+Name
+
+    ANGLE_device_mtl
+
+Name Strings
+
+    EGL_ANGLE_device_mtl
+
+Contributors
+
+    Le Hoang Quyen
+
+Contact
+
+    Le Hoang Quyen (lehoangq 'at' gmail.com)
+
+Status
+
+    Draft
+
+Version
+
+    Version 1, Jul 19, 2020
+
+Number
+
+    EGL Extension #XXX
+
+Extension Type
+
+    EGL device extension
+
+Dependencies
+
+    This extension is written against the language of EGL 1.5 as
+    modified by EGL_EXT_device_query.
+
+    EGL_EXT_device_query is required.
+
+Overview
+
+    ANGLE has the ability to run GPU commands on a metal device.
+    This extension defines a mapping from an EGL device to a metal
+    device, after it's queried from an EGL display.
+
+IP Status
+
+    No known claims.
+
+New Types
+
+    None.
+
+New Procedures and Functions
+
+    None.
+
+New Tokens
+
+    Accepted as a queried <attribute> in eglQueryDeviceAttribEXT:
+
+        EGL_MTL_DEVICE_ANGLE              0x33A2
+
+Add a new section 2.1.3 (Metal Devices) after 2.1.2 (Devices)
+
+    Somewhat analogous to an EGL device, a Metal device establishes a
+    namespace for Metal operations. In the Metal APIs, such devices are
+    represented by pointers. For more details, see the Metal
+    documentation.
+
+Changes to section 3.2 (Devices)
+
+    Replace the paragraph immediately following the prototype for
+    eglQueryDeviceAttribEXT:
+
+    <attribute> may be EGL_MTL_DEVICE_ANGLE.
+    On success, EGL_TRUE is returned, and a valid MTLDevice pointer
+    corresponding to the EGL device is returned in <value>. This handle
+    is compatible with Metal API functions. If the EGL device is not currently
+    associated with a Metal device and <attribute> is EGL_MTL_DEVICE_ANGLE,
+    EGL_BAD_ATTRIBUTE is returned, and <value> is left unchanged.
+
+Issues
+
+    None
+
+Revision History
+
+    Version 1, Jul 19, 2020 (Le Hoang Quyen)
+        - Initial Draft

include/EGL/eglext_angle.h

@@ -254,6 +254,11 @@ EGLAPI EGLBoolean EGLAPIENTRY eglQueryDisplayAttribANGLE(EGLDisplay dpy, EGLint
 #define EGL_CGL_PIXEL_FORMAT_ANGLE 0x3486
 #endif
 
+#ifndef EGL_ANGLE_device_mtl
+#define EGL_ANGLE_device_mtl 1
+#define EGL_MTL_DEVICE_ANGLE 0x33A2
+#endif /* EGL_ANGLE_device_mtl */
+
 // clang-format on
 
 #endif  // INCLUDE_EGL_EGLEXT_ANGLE_

src/libANGLE/Caps.cpp

@@ -1274,6 +1274,7 @@ std::vector<std::string> DeviceExtensions::getStrings() const
     //                   | Extension name                                 | Supported flag                | Output vector   |
     InsertExtensionString("EGL_ANGLE_device_d3d",                          deviceD3D,                      &extensionStrings);
     InsertExtensionString("EGL_ANGLE_device_cgl",                          deviceCGL,                      &extensionStrings);
+    InsertExtensionString("EGL_ANGLE_device_mtl",                          deviceMTL,                      &extensionStrings);
     // clang-format on
 
     return extensionStrings;

src/libANGLE/Caps.h

@@ -975,6 +975,9 @@ struct DeviceExtensions
 
     // EGL_ANGLE_device_cgl
     bool deviceCGL = false;
+
+    // EGL_ANGLE_device_mtl
+    bool deviceMTL = false;
 };
 
 struct ClientExtensions

src/libANGLE/renderer/metal/DisplayMtl.mm

@@ -11,6 +11,7 @@
 #include "libANGLE/Context.h"
 #include "libANGLE/Display.h"
 #include "libANGLE/Surface.h"
+#include "libANGLE/renderer/DeviceImpl.h"
 #include "libANGLE/renderer/glslang_wrapper_utils.h"
 #include "libANGLE/renderer/metal/ContextMtl.h"
 #include "libANGLE/renderer/metal/SurfaceMtl.h"
@@ -43,6 +44,37 @@ bool IsMetalDisplayAvailable()
     return new DisplayMtl(state);
 }
 
+// DeviceMTL implementation, implements DeviceImpl
+class DeviceMTL : public DeviceImpl
+{
+  public:
+    DeviceMTL() {}
+    ~DeviceMTL() override {}
+
+    egl::Error initialize() override { return egl::NoError(); }
+    egl::Error getAttribute(const egl::Display *display, EGLint attribute, void **outValue) override
+    {
+        DisplayMtl *displayImpl = mtl::GetImpl(display);
+
+        switch (attribute)
+        {
+            case EGL_MTL_DEVICE_ANGLE:
+                *outValue = displayImpl->getMetalDevice();
+                break;
+            default:
+                return egl::EglBadAttribute();
+        }
+
+        return egl::NoError();
+    }
+    EGLint getType() override { return 0; }
+    void generateExtensions(egl::DeviceExtensions *outExtensions) const override
+    {
+        outExtensions->deviceMTL = true;
+    }
+};
+
+// DisplayMtl implementation
 DisplayMtl::DisplayMtl(const egl::DisplayState &state)
     : DisplayImpl(state), mStateCache(mFeatures), mUtils(this)
 {}
@@ -125,8 +157,7 @@ bool IsMetalDisplayAvailable()
 
 DeviceImpl *DisplayMtl::createDevice()
 {
-    UNIMPLEMENTED();
-    return nullptr;
+    return new DeviceMTL();
 }
 
 egl::Error DisplayMtl::waitClient(const gl::Context *context)
@@ -237,6 +268,7 @@ bool IsMetalDisplayAvailable()
     outExtensions->fenceSync                    = true;
     outExtensions->waitSync                     = true;
     outExtensions->glColorspace                 = true;
+    outExtensions->deviceQuery                  = true;
 }
 
 void DisplayMtl::generateCaps(egl::Caps *outCaps) const {}

src/libGLESv2/entry_points_egl_ext.cpp

@@ -301,6 +301,15 @@ EGLBoolean EGLAPIENTRY EGL_QueryDeviceAttribEXT(EGLDeviceEXT device,
             }
             error = dev->getAttribute(attribute, value);
             break;
+        case EGL_MTL_DEVICE_ANGLE:
+            if (!dev->getExtensions().deviceMTL)
+            {
+                thread->setError(EglBadAttribute(), GetDebug(), "eglQueryDeviceAttribEXT",
+                                 GetDeviceIfValid(dev));
+                return EGL_FALSE;
+            }
+            error = dev->getAttribute(attribute, value);
+            break;
         case EGL_CGL_CONTEXT_ANGLE:
         case EGL_CGL_PIXEL_FORMAT_ANGLE:
             if (!dev->getExtensions().deviceCGL)