3 files changed, 20 insertions, 10 deletions

diff --git a/src/gpu/GrShaderCaps.cpp b/src/gpu/GrShaderCaps.cpp
index 90c2e68a93..0ee9339b45 100644
--- a/src/gpu/GrShaderCaps.cpp
+++ b/src/gpu/GrShaderCaps.cpp
@@ -43,6 +43,7 @@ GrShaderCaps::GrShaderCaps(const GrContextOptions& options) {
     fGLSLGeneration = k330_GrGLSLGeneration;
     fShaderDerivativeSupport = false;
     fGeometryShaderSupport = false;
+    fGSInvocationsSupport = false;
     fPathRenderingSupport = false;
     fDstReadInShaderSupport = false;
     fDualSourceBlendingSupport = false;
@@ -61,7 +62,6 @@ GrShaderCaps::GrShaderCaps(const GrContextOptions& options) {
     fMustForceNegatedAtanParamToFloat = false;
     fAtan2ImplementedAsAtanYOverX = false;
     fRequiresLocalOutputColorForFBFetch = false;
-    fMustImplementGSInvocationsWithLoop = false;
     fMustObfuscateUniformColor = false;
     fMustGuardDivisionEvenAfterExplicitZeroCheck = false;
     fFlatInterpolationSupport = false;
@@ -76,6 +76,7 @@ GrShaderCaps::GrShaderCaps(const GrContextOptions& options) {
 
     fVersionDeclString = nullptr;
     fShaderDerivativeExtensionString = nullptr;
+    fGSInvocationsExtensionString = nullptr;
     fFragCoordConventionsExtensionString = nullptr;
     fSecondaryOutputExtensionString = nullptr;
     fExternalTextureExtensionString = nullptr;
@@ -102,6 +103,7 @@ void GrShaderCaps::dumpJSON(SkJSONWriter* writer) const {
 
     writer->appendBool("Shader Derivative Support", fShaderDerivativeSupport);
     writer->appendBool("Geometry Shader Support", fGeometryShaderSupport);
+    writer->appendBool("Geometry Shader Invocations Support", fGSInvocationsSupport);
     writer->appendBool("Path Rendering Support", fPathRenderingSupport);
     writer->appendBool("Dst Read In Shader Support", fDstReadInShaderSupport);
     writer->appendBool("Dual Source Blending Support", fDualSourceBlendingSupport);
@@ -150,8 +152,6 @@ void GrShaderCaps::dumpJSON(SkJSONWriter* writer) const {
     writer->appendBool("Can use fract() for negative values", fCanUseFractForNegativeValues);
     writer->appendBool("Must force negated atan param to float", fMustForceNegatedAtanParamToFloat);
     writer->appendBool("Must use local out color for FBFetch", fRequiresLocalOutputColorForFBFetch);
-    writer->appendBool("Must implement geo shader invocations with loop",
-                       fMustImplementGSInvocationsWithLoop);
     writer->appendBool("Must obfuscate uniform color", fMustObfuscateUniformColor);
     writer->appendBool("Must guard division even after explicit zero check",
                        fMustGuardDivisionEvenAfterExplicitZeroCheck);
diff --git a/src/gpu/gl/GrGLCaps.cpp b/src/gpu/gl/GrGLCaps.cpp
index c424b84a1a..21aadd59f6 100644
--- a/src/gpu/gl/GrGLCaps.cpp
+++ b/src/gpu/gl/GrGLCaps.cpp
@@ -307,10 +307,24 @@ void GrGLCaps::init(const GrContextOptions& contextOptions,
         shaderCaps->fDualSourceBlendingSupport = (ctxInfo.version() >= GR_GL_VER(3, 3) ||
             ctxInfo.hasExtension("GL_ARB_blend_func_extended")) &&
             GrGLSLSupportsNamedFragmentShaderOutputs(ctxInfo.glslGeneration());
+
         shaderCaps->fShaderDerivativeSupport = true;
+
         // we don't support GL_ARB_geometry_shader4, just GL 3.2+ GS
         shaderCaps->fGeometryShaderSupport = ctxInfo.version() >= GR_GL_VER(3, 2) &&
             ctxInfo.glslGeneration() >= k150_GrGLSLGeneration;
+        if (shaderCaps->fGeometryShaderSupport) {
+            // On at least some MacBooks, GLSL 4.0 geometry shaders break if we use invocations.
+#ifndef SK_BUILD_FOR_MAC
+            if (ctxInfo.glslGeneration() >= k400_GrGLSLGeneration) {
+                shaderCaps->fGSInvocationsSupport = true;
+            } else if (ctxInfo.hasExtension("GL_ARB_gpu_shader5")) {
+                shaderCaps->fGSInvocationsSupport = true;
+                shaderCaps->fGSInvocationsExtensionString = "GL_ARB_gpu_shader5";
+            }
+#endif
+        }
+
         shaderCaps->fIntegerSupport = ctxInfo.version() >= GR_GL_VER(3, 0) &&
             ctxInfo.glslGeneration() >= k130_GrGLSLGeneration;
     }
@@ -321,6 +335,7 @@ void GrGLCaps::init(const GrContextOptions& contextOptions,
             ctxInfo.hasExtension("GL_OES_standard_derivatives");
 
         shaderCaps->fGeometryShaderSupport = ctxInfo.hasExtension("GL_EXT_geometry_shader");
+        shaderCaps->fGSInvocationsSupport = shaderCaps->fGeometryShaderSupport;
 
         shaderCaps->fIntegerSupport = ctxInfo.version() >= GR_GL_VER(3, 0) &&
             ctxInfo.glslGeneration() >= k330_GrGLSLGeneration; // We use this value for GLSL ES 3.0.
@@ -938,13 +953,6 @@ void GrGLCaps::initGLSL(const GrGLContextInfo& ctxInfo) {
         shaderCaps->fRequiresLocalOutputColorForFBFetch = true;
     }
 
-#ifdef SK_BUILD_FOR_MAC
-    // On at least some MacBooks, geometry shaders fall apart if we use more than one invocation. To
-    // work around this, we always use a single invocation and wrap the shader in a loop. The long-
-    // term plan for this WAR is for it to eventually be baked into SkSL.
-    shaderCaps->fMustImplementGSInvocationsWithLoop = true;
-#endif
-
     // Newer Mali GPUs do incorrect static analysis in specific situations: If there is uniform
     // color, and that uniform contains an opaque color, and the output of the shader is only based
     // on that uniform plus soemthing un-trackable (like a texture read), the compiler will deduce
diff --git a/src/gpu/vk/GrVkCaps.cpp b/src/gpu/vk/GrVkCaps.cpp
index c92c7d59f9..1b0db7fb23 100644
--- a/src/gpu/vk/GrVkCaps.cpp
+++ b/src/gpu/vk/GrVkCaps.cpp
@@ -242,7 +242,9 @@ void GrVkCaps::initShaderCaps(const VkPhysicalDeviceProperties& properties, uint
     // GrShaderCaps
 
     shaderCaps->fShaderDerivativeSupport = true;
+
     shaderCaps->fGeometryShaderSupport = SkToBool(featureFlags & kGeometryShader_GrVkFeatureFlag);
+    shaderCaps->fGSInvocationsSupport = shaderCaps->fGeometryShaderSupport;
 
     shaderCaps->fDualSourceBlendingSupport = SkToBool(featureFlags & kDualSrcBlend_GrVkFeatureFlag);
     if (kAMD_VkVendor == properties.vendorID) {