From 93d4c10ffccc2faf2e38bab74ba14414751bae91 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?K=C3=A1ri=20Tristan=20Helgason?= <kthelgason@webrtc.org>
Date: Mon, 19 Aug 2019 15:17:37 +0200
Subject: [PATCH] Declare references as constant in the metal renderers.
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This silences a warning that appeared with iOS 13, and is more efficient
in general.

Bug: webrtc:10866
Change-Id: I23db6b78af36e59b1d825d3f0cccc6008f9b626a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/149808
Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
Reviewed-by: Anders Carlsson <andersc@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28911}
---
 sdk/objc/components/renderer/metal/RTCMTLI420Renderer.mm | 7 ++++---
 sdk/objc/components/renderer/metal/RTCMTLNV12Renderer.mm | 7 ++++---
 sdk/objc/components/renderer/metal/RTCMTLRGBRenderer.mm  | 8 ++++----
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/sdk/objc/components/renderer/metal/RTCMTLI420Renderer.mm b/sdk/objc/components/renderer/metal/RTCMTLI420Renderer.mm
index a6e22035bd..6cd7ff3055 100644
--- a/sdk/objc/components/renderer/metal/RTCMTLI420Renderer.mm
+++ b/sdk/objc/components/renderer/metal/RTCMTLI420Renderer.mm
@@ -33,10 +33,10 @@ static NSString *const shaderSource = MTL_STRINGIFY(
       float2 texcoord;
     } Varyings;
 
-    vertex Varyings vertexPassthrough(device Vertex * verticies[[buffer(0)]],
+    vertex Varyings vertexPassthrough(constant Vertex *verticies[[buffer(0)]],
                                       unsigned int vid[[vertex_id]]) {
       Varyings out;
-      device Vertex &v = verticies[vid];
+      constant Vertex &v = verticies[vid];
       out.position = float4(float2(v.position), 0.0, 1.0);
       out.texcoord = v.texcoord;
 
@@ -44,7 +44,8 @@ static NSString *const shaderSource = MTL_STRINGIFY(
     }
 
     fragment half4 fragmentColorConversion(
-        Varyings in[[stage_in]], texture2d<float, access::sample> textureY[[texture(0)]],
+        Varyings in[[stage_in]],
+        texture2d<float, access::sample> textureY[[texture(0)]],
         texture2d<float, access::sample> textureU[[texture(1)]],
         texture2d<float, access::sample> textureV[[texture(2)]]) {
       constexpr sampler s(address::clamp_to_edge, filter::linear);
diff --git a/sdk/objc/components/renderer/metal/RTCMTLNV12Renderer.mm b/sdk/objc/components/renderer/metal/RTCMTLNV12Renderer.mm
index bc5e982dbd..98835cb518 100644
--- a/sdk/objc/components/renderer/metal/RTCMTLNV12Renderer.mm
+++ b/sdk/objc/components/renderer/metal/RTCMTLNV12Renderer.mm
@@ -34,10 +34,10 @@ static NSString *const shaderSource = MTL_STRINGIFY(
       float2 texcoord;
     } Varyings;
 
-    vertex Varyings vertexPassthrough(device Vertex * verticies[[buffer(0)]],
+    vertex Varyings vertexPassthrough(constant Vertex *verticies[[buffer(0)]],
                                       unsigned int vid[[vertex_id]]) {
       Varyings out;
-      device Vertex &v = verticies[vid];
+      constant Vertex &v = verticies[vid];
       out.position = float4(float2(v.position), 0.0, 1.0);
       out.texcoord = v.texcoord;
       return out;
@@ -45,7 +45,8 @@ static NSString *const shaderSource = MTL_STRINGIFY(
 
     // Receiving YCrCb textures.
     fragment half4 fragmentColorConversion(
-        Varyings in[[stage_in]], texture2d<float, access::sample> textureY[[texture(0)]],
+        Varyings in[[stage_in]],
+        texture2d<float, access::sample> textureY[[texture(0)]],
         texture2d<float, access::sample> textureCbCr[[texture(1)]]) {
       constexpr sampler s(address::clamp_to_edge, filter::linear);
       float y;
diff --git a/sdk/objc/components/renderer/metal/RTCMTLRGBRenderer.mm b/sdk/objc/components/renderer/metal/RTCMTLRGBRenderer.mm
index d03d71f884..eb4c2ba106 100644
--- a/sdk/objc/components/renderer/metal/RTCMTLRGBRenderer.mm
+++ b/sdk/objc/components/renderer/metal/RTCMTLRGBRenderer.mm
@@ -34,17 +34,17 @@ static NSString *const shaderSource = MTL_STRINGIFY(
       float2 texcoord;
     } VertexIO;
 
-    vertex VertexIO vertexPassthrough(device Vertex * verticies[[buffer(0)]],
+    vertex VertexIO vertexPassthrough(constant Vertex *verticies[[buffer(0)]],
                                       uint vid[[vertex_id]]) {
       VertexIO out;
-      device Vertex &v = verticies[vid];
+      constant Vertex &v = verticies[vid];
       out.position = float4(float2(v.position), 0.0, 1.0);
       out.texcoord = v.texcoord;
       return out;
     }
 
-    fragment half4 fragmentColorConversion(
-        VertexIO in[[stage_in]], texture2d<half, access::sample> texture[[texture(0)]],
+    fragment half4 fragmentColorConversion(VertexIO in[[stage_in]],
+                                           texture2d<half, access::sample> texture[[texture(0)]],
                                            constant bool &isARGB[[buffer(0)]]) {
       constexpr sampler s(address::clamp_to_edge, filter::linear);