added support for PLS path rendering

BUG=skia:3555
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1541903002

Committed: https://skia.googlesource.com/skia/+/7df3f5e127f8016d17b637cc48a6a4718f1a6822

Review URL: https://codereview.chromium.org/1541903002

6 files changed, 29 insertions, 16 deletions

diff --git a/src/gpu/effects/GrCoverageSetOpXP.cpp b/src/gpu/effects/GrCoverageSetOpXP.cpp
index 7761a6445a..8c98c6c843 100644
--- a/src/gpu/effects/GrCoverageSetOpXP.cpp
+++ b/src/gpu/effects/GrCoverageSetOpXP.cpp
@@ -9,6 +9,7 @@
 #include "effects/GrCoverageSetOpXP.h"
 #include "GrCaps.h"
 #include "GrColor.h"
+#include "GrPipeline.h"
 #include "GrProcessor.h"
 #include "GrProcOptInfo.h"
 #include "glsl/GrGLSLBlend.h"
@@ -151,7 +152,6 @@ class ShaderCSOXferProcessor : public GrXferProcessor {
 public:
     ShaderCSOXferProcessor(const DstTexture* dstTexture,
                            bool hasMixedSamples,
-                           SkXfermode::Mode xfermode,
                            SkRegion::Op regionOp,
                            bool invertCoverage)
         : INHERITED(dstTexture, true, hasMixedSamples)
@@ -323,6 +323,9 @@ GrCoverageSetOpXPFactory::onCreateXferProcessor(const GrCaps& caps,
         return nullptr;
     }
 
+    if (optimizations.fOverrides.fUsePLSDstRead) {
+        return new ShaderCSOXferProcessor(dst, hasMixedSamples, fRegionOp, fInvertCoverage);
+    }
     return CoverageSetOpXP::Create(fRegionOp, fInvertCoverage);
 }
 
diff --git a/src/gpu/effects/GrCustomXfermode.cpp b/src/gpu/effects/GrCustomXfermode.cpp
index 459ff52948..dccec0c599 100644
--- a/src/gpu/effects/GrCustomXfermode.cpp
+++ b/src/gpu/effects/GrCustomXfermode.cpp
@@ -54,12 +54,15 @@ static GrBlendEquation hw_blend_equation(SkXfermode::Mode mode) {
 }
 
 static bool can_use_hw_blend_equation(GrBlendEquation equation,
-                                      const GrProcOptInfo& coveragePOI,
+                                      const GrPipelineOptimizations& opt,
                                       const GrCaps& caps) {
     if (!caps.advancedBlendEquationSupport()) {
         return false;
     }
-    if (coveragePOI.isFourChannelOutput()) {
+    if (opt.fOverrides.fUsePLSDstRead) {
+        return false;
+    }
+    if (opt.fCoveragePOI.isFourChannelOutput()) {
         return false; // LCD coverage must be applied after the blend equation.
     }
     if (caps.canUseAdvancedBlendEquation(equation)) {
@@ -334,7 +337,7 @@ private:
                                            bool hasMixedSamples,
                                            const DstTexture*) const override;
 
-    bool willReadDstColor(const GrCaps& caps,
+    bool onWillReadDstColor(const GrCaps& caps,
                           const GrPipelineOptimizations& optimizations,
                           bool hasMixedSamples) const override;
 
@@ -362,17 +365,17 @@ GrXferProcessor* CustomXPFactory::onCreateXferProcessor(const GrCaps& caps,
                                                         const GrPipelineOptimizations& opt,
                                                         bool hasMixedSamples,
                                                         const DstTexture* dstTexture) const {
-    if (can_use_hw_blend_equation(fHWBlendEquation, opt.fCoveragePOI, caps)) {
+    if (can_use_hw_blend_equation(fHWBlendEquation, opt, caps)) {
         SkASSERT(!dstTexture || !dstTexture->texture());
         return new CustomXP(fMode, fHWBlendEquation);
     }
     return new CustomXP(dstTexture, hasMixedSamples, fMode);
 }
 
-bool CustomXPFactory::willReadDstColor(const GrCaps& caps,
-                                       const GrPipelineOptimizations& optimizations,
-                                       bool hasMixedSamples) const {
-    return !can_use_hw_blend_equation(fHWBlendEquation, optimizations.fCoveragePOI, caps);
+bool CustomXPFactory::onWillReadDstColor(const GrCaps& caps,
+                                         const GrPipelineOptimizations& optimizations,
+                                         bool hasMixedSamples) const {
+    return !can_use_hw_blend_equation(fHWBlendEquation, optimizations, caps);
 }
 
 void CustomXPFactory::getInvariantBlendedColor(const GrProcOptInfo& colorPOI,
diff --git a/src/gpu/effects/GrDashingEffect.cpp b/src/gpu/effects/GrDashingEffect.cpp
index 1516efd2b2..09dc90a529 100644
--- a/src/gpu/effects/GrDashingEffect.cpp
+++ b/src/gpu/effects/GrDashingEffect.cpp
@@ -275,7 +275,6 @@ public:
         // When this is called on a batch, there is only one geometry bundle
         color->setKnownFourComponents(fGeoData[0].fColor);
         coverage->setUnknownSingleComponent();
-        overrides->fUsePLSDstRead = false;
     }
 
     SkSTArray<1, Geometry, true>* geoData() { return &fGeoData; }
diff --git a/src/gpu/effects/GrDisableColorXP.cpp b/src/gpu/effects/GrDisableColorXP.cpp
index 70e40e4a14..937bea8c35 100644
--- a/src/gpu/effects/GrDisableColorXP.cpp
+++ b/src/gpu/effects/GrDisableColorXP.cpp
@@ -6,6 +6,7 @@
  */
 
 #include "effects/GrDisableColorXP.h"
+#include "GrPipeline.h"
 #include "GrProcessor.h"
 #include "glsl/GrGLSLFragmentShaderBuilder.h"
 #include "glsl/GrGLSLProgramDataManager.h"
@@ -97,6 +98,7 @@ GrDisableColorXPFactory::onCreateXferProcessor(const GrCaps& caps,
                                                const GrPipelineOptimizations& optimizations,
                                                bool hasMixedSamples,
                                                const DstTexture* dst) const {
+    SkASSERT(!optimizations.fOverrides.fUsePLSDstRead);
     return DisableColorXP::Create();
 }
 
diff --git a/src/gpu/effects/GrDisableColorXP.h b/src/gpu/effects/GrDisableColorXP.h
index 94aae31751..21e69327f6 100644
--- a/src/gpu/effects/GrDisableColorXP.h
+++ b/src/gpu/effects/GrDisableColorXP.h
@@ -31,9 +31,9 @@ private:
                                            bool hasMixedSamples,
                                            const DstTexture* dstTexture) const override;
 
-    bool willReadDstColor(const GrCaps& caps,
-                          const GrPipelineOptimizations& optimizations,
-                          bool hasMixedSamples) const override {
+    bool onWillReadDstColor(const GrCaps& caps,
+                            const GrPipelineOptimizations& optimizations,
+                            bool hasMixedSamples) const override {
         return false;
     }
 
diff --git a/src/gpu/effects/GrPorterDuffXferProcessor.cpp b/src/gpu/effects/GrPorterDuffXferProcessor.cpp
index c443e1e992..d1059c7c7b 100644
--- a/src/gpu/effects/GrPorterDuffXferProcessor.cpp
+++ b/src/gpu/effects/GrPorterDuffXferProcessor.cpp
@@ -739,6 +739,9 @@ GrPorterDuffXPFactory::onCreateXferProcessor(const GrCaps& caps,
                                              const GrPipelineOptimizations& optimizations,
                                              bool hasMixedSamples,
                                              const DstTexture* dstTexture) const {
+    if (optimizations.fOverrides.fUsePLSDstRead) {
+        return new ShaderPDXferProcessor(dstTexture, hasMixedSamples, fXfermode);
+    }
     BlendFormula blendFormula;
     if (optimizations.fCoveragePOI.isFourChannelOutput()) {
         if (SkXfermode::kSrcOver_Mode == fXfermode &&
@@ -795,9 +798,9 @@ void GrPorterDuffXPFactory::getInvariantBlendedColor(const GrProcOptInfo& colorP
     }
 }
 
-bool GrPorterDuffXPFactory::willReadDstColor(const GrCaps& caps,
-                                             const GrPipelineOptimizations& optimizations,
-                                             bool hasMixedSamples) const {
+bool GrPorterDuffXPFactory::onWillReadDstColor(const GrCaps& caps,
+                                               const GrPipelineOptimizations& optimizations,
+                                               bool hasMixedSamples) const {
     if (caps.shaderCaps()->dualSourceBlendingSupport()) {
         return false;
     }
@@ -854,6 +857,9 @@ GrXferProcessor* GrPorterDuffXPFactory::CreateSrcOverXferProcessor(
         const GrPipelineOptimizations& optimizations,
         bool hasMixedSamples,
         const GrXferProcessor::DstTexture* dstTexture) {
+    if (optimizations.fOverrides.fUsePLSDstRead) {
+        return new ShaderPDXferProcessor(dstTexture, hasMixedSamples, SkXfermode::kSrcOver_Mode);
+    }
     if (!optimizations.fCoveragePOI.isFourChannelOutput() &&
         !(optimizations.fCoveragePOI.isSolidWhite() &&
           !hasMixedSamples &&