Add flag to avoid stencil buffers in Skia

Certain systems experience a leak in the GL driver associated with
stencil buffers. Attempts to avoid the leak (while still using stencil
buffers) dind't succeed. This patch adds a GrContextOption
fAvoidStencilBuffers. This disables certain path rendering modes, as
well as stencil based masking/clipping.

Bug: 713854
Change-Id: Ifa6c0f2bd5ee395547bda9165d6c79d197ae8b8b
Reviewed-on: https://skia-review.googlesource.com/15253
Commit-Queue: Eric Karl <ericrk@chromium.org>
Reviewed-by: Eric Karl <ericrk@chromium.org>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/GrCaps.cpp b/src/gpu/GrCaps.cpp
index 57ab5fd..4acf90e 100644
--- a/src/gpu/GrCaps.cpp
+++ b/src/gpu/GrCaps.cpp
@@ -77,6 +77,7 @@
     fUseDrawInsteadOfPartialRenderTargetWrite = options.fUseDrawInsteadOfPartialRenderTargetWrite;
     fUseDrawInsteadOfAllRenderTargetWrites = false;
     fAvoidInstancedDrawsToFPTargets = false;
+    fAvoidStencilBuffers = false;
 
     fPreferVRAMUseOverFlushes = true;
 }
@@ -95,6 +96,7 @@
                  GrWindowRectangles::kMaxWindows, fMaxWindowRectangles);
         fMaxWindowRectangles = GrWindowRectangles::kMaxWindows;
     }
+    fAvoidStencilBuffers = options.fAvoidStencilBuffers;
 }
 
 static SkString map_flags_to_string(uint32_t flags) {
diff --git a/src/gpu/GrClipStackClip.cpp b/src/gpu/GrClipStackClip.cpp
index 18df1d6..e24e635 100644
--- a/src/gpu/GrClipStackClip.cpp
+++ b/src/gpu/GrClipStackClip.cpp
@@ -115,7 +115,7 @@
 
         GrShape shape(path, GrStyle::SimpleFill());
         GrPathRenderer::CanDrawPathArgs canDrawArgs;
-        canDrawArgs.fShaderCaps = context->caps()->shaderCaps();
+        canDrawArgs.fCaps = context->caps();
         canDrawArgs.fViewMatrix = &viewMatrix;
         canDrawArgs.fShape = &shape;
         if (!element->isAA()) {
@@ -152,6 +152,10 @@
     // a clip gets complex enough it can just be done in SW regardless
     // of whether it would invoke the GrSoftwarePathRenderer.
 
+    // If we're avoiding stencils, always use SW:
+    if (context->caps()->avoidStencilBuffers())
+        return true;
+
     // Set the matrix so that rendered clip elements are transformed to mask space from clip
     // space.
     SkMatrix translate;
@@ -283,6 +287,8 @@
     SkASSERT(rtIBounds.contains(clipIBounds)); // Mask shouldn't be larger than the RT.
 #endif
 
+    bool avoidStencilBuffers = context->caps()->avoidStencilBuffers();
+
     // An element count of 4 was chosen because of the common pattern in Blink of:
     //   isect RR
     //   diff  RR
@@ -294,7 +300,8 @@
     if (reducedClip.elements().count() <= kMaxAnalyticElements) {
         // When there are multiple samples we want to do per-sample clipping, not compute a
         // fractional pixel coverage.
-        bool disallowAnalyticAA = renderTargetContext->isStencilBufferMultisampled();
+        bool disallowAnalyticAA = renderTargetContext->isStencilBufferMultisampled() &&
+                                  !avoidStencilBuffers;
         if (disallowAnalyticAA && !renderTargetContext->numColorSamples()) {
             // With a single color sample, any coverage info is lost from color once it hits the
             // color buffer anyway, so we may as well use coverage AA if nothing else in the pipe
@@ -302,7 +309,7 @@
             disallowAnalyticAA = useHWAA || hasUserStencilSettings;
         }
         sk_sp<GrFragmentProcessor> clipFP;
-        if (reducedClip.requiresAA() &&
+        if ((reducedClip.requiresAA() || avoidStencilBuffers) &&
             get_analytic_clip_processor(reducedClip.elements(), disallowAnalyticAA, devBounds,
                                         &clipFP)) {
             out->addCoverageFP(std::move(clipFP));
@@ -311,7 +318,8 @@
     }
 
     // If the stencil buffer is multisampled we can use it to do everything.
-    if (!renderTargetContext->isStencilBufferMultisampled() && reducedClip.requiresAA()) {
+    if ((!renderTargetContext->isStencilBufferMultisampled() && reducedClip.requiresAA()) ||
+        avoidStencilBuffers) {
         sk_sp<GrTextureProxy> result;
         if (UseSWOnlyPath(context, hasUserStencilSettings, renderTargetContext, reducedClip)) {
             // The clip geometry is complex enough that it will be more efficient to create it
@@ -328,7 +336,13 @@
                                                   reducedClip.ibounds()));
             return true;
         }
-        // if alpha clip mask creation fails fall through to the non-AA code paths
+
+        // If alpha or software clip mask creation fails, fall through to the stencil code paths,
+        // unless stencils are disallowed.
+        if (context->caps()->avoidStencilBuffers()) {
+            SkDebugf("WARNING: Clip mask requires stencil, but stencil unavailable. Clip will be ignored.\n");
+            return false;
+        }
     }
 
     GrRenderTarget* rt = renderTargetContext->accessRenderTarget();
diff --git a/src/gpu/GrGpu.cpp b/src/gpu/GrGpu.cpp
index f8ac850..ceb0dee 100644
--- a/src/gpu/GrGpu.cpp
+++ b/src/gpu/GrGpu.cpp
@@ -197,10 +197,13 @@
     if (!tex) {
         return nullptr;
     }
-    // TODO: defer this and attach dynamically
-    GrRenderTarget* tgt = tex->asRenderTarget();
-    if (tgt && !fContext->resourceProvider()->attachStencilAttachment(tgt)) {
-        return nullptr;
+
+    if (!this->caps()->avoidStencilBuffers()) {
+        // TODO: defer this and attach dynamically
+        GrRenderTarget* tgt = tex->asRenderTarget();
+        if (tgt && !fContext->resourceProvider()->attachStencilAttachment(tgt)) {
+            return nullptr;
+        }
     }
     return tex;
 }
diff --git a/src/gpu/GrPathRenderer.h b/src/gpu/GrPathRenderer.h
index 05673d5..0845bc0 100644
--- a/src/gpu/GrPathRenderer.h
+++ b/src/gpu/GrPathRenderer.h
@@ -74,14 +74,14 @@
 
     /** Args to canDrawPath()
      *
-     * fShaderCaps       The shader caps
+     * fCaps             The context caps
      * fPipelineBuilder  The pipelineBuilder
      * fViewMatrix       The viewMatrix
      * fShape            The shape to draw
      * fAntiAlias        The type of anti aliasing required.
      */
     struct CanDrawPathArgs {
-        const GrShaderCaps*         fShaderCaps;
+        const GrCaps*               fCaps;
         const SkMatrix*             fViewMatrix;
         const GrShape*              fShape;
         GrAAType                    fAAType;
@@ -91,7 +91,7 @@
 
 #ifdef SK_DEBUG
         void validate() const {
-            SkASSERT(fShaderCaps);
+            SkASSERT(fCaps);
             SkASSERT(fViewMatrix);
             SkASSERT(fShape);
         }
@@ -153,7 +153,7 @@
         SkDEBUGCODE(args.validate();)
 #ifdef SK_DEBUG
         CanDrawPathArgs canArgs;
-        canArgs.fShaderCaps = args.fContext->caps()->shaderCaps();
+        canArgs.fCaps = args.fContext->caps();
         canArgs.fViewMatrix = args.fViewMatrix;
         canArgs.fShape = args.fShape;
         canArgs.fAAType = args.fAAType;
diff --git a/src/gpu/GrReducedClip.cpp b/src/gpu/GrReducedClip.cpp
index 4b7e69b..28ba47c 100644
--- a/src/gpu/GrReducedClip.cpp
+++ b/src/gpu/GrReducedClip.cpp
@@ -730,7 +730,7 @@
 
             GrShape shape(clipPath, GrStyle::SimpleFill());
             GrPathRenderer::CanDrawPathArgs canDrawArgs;
-            canDrawArgs.fShaderCaps = context->caps()->shaderCaps();
+            canDrawArgs.fCaps = context->caps();
             canDrawArgs.fViewMatrix = &SkMatrix::I();
             canDrawArgs.fShape = &shape;
             canDrawArgs.fAAType = aaType;
diff --git a/src/gpu/GrRenderTargetContext.cpp b/src/gpu/GrRenderTargetContext.cpp
index 7de1f8d..fc1ab68 100644
--- a/src/gpu/GrRenderTargetContext.cpp
+++ b/src/gpu/GrRenderTargetContext.cpp
@@ -1425,8 +1425,7 @@
 
     GrShape shape(path, GrStyle::SimpleFill());
     GrPathRenderer::CanDrawPathArgs canDrawArgs;
-    canDrawArgs.fShaderCaps =
-        fRenderTargetContext->drawingManager()->getContext()->caps()->shaderCaps();
+    canDrawArgs.fCaps = fRenderTargetContext->drawingManager()->getContext()->caps();
     canDrawArgs.fViewMatrix = &viewMatrix;
     canDrawArgs.fShape = &shape;
     canDrawArgs.fAAType = aaType;
@@ -1487,7 +1486,7 @@
         aaType = GrAAType::kCoverage;
     }
     GrPathRenderer::CanDrawPathArgs canDrawArgs;
-    canDrawArgs.fShaderCaps = this->drawingManager()->getContext()->caps()->shaderCaps();
+    canDrawArgs.fCaps = this->drawingManager()->getContext()->caps();
     canDrawArgs.fViewMatrix = &viewMatrix;
     canDrawArgs.fShape = &shape;
     canDrawArgs.fHasUserStencilSettings = false;
diff --git a/src/gpu/GrSoftwarePathRenderer.cpp b/src/gpu/GrSoftwarePathRenderer.cpp
index 0e7cecd..a9613b4 100644
--- a/src/gpu/GrSoftwarePathRenderer.cpp
+++ b/src/gpu/GrSoftwarePathRenderer.cpp
@@ -136,7 +136,9 @@
     bool inverseFilled = false;
     SkTLazy<GrShape> tmpShape;
     SkASSERT(!args.fShape->style().applies());
-    inverseFilled = args.fShape->inverseFilled();
+    // If the path is hairline, ignore inverse fill.
+    inverseFilled = args.fShape->inverseFilled() &&
+                    !IsStrokeHairlineOrEquivalent(args.fShape->style(), *args.fViewMatrix, nullptr);
 
     SkIRect unclippedDevShapeBounds, clippedDevShapeBounds, devClipBounds;
     // To prevent overloading the cache with entries during animations we limit the cache of masks
diff --git a/src/gpu/gl/GrGLCaps.cpp b/src/gpu/gl/GrGLCaps.cpp
index 47f26ff..2c2f7ec 100644
--- a/src/gpu/gl/GrGLCaps.cpp
+++ b/src/gpu/gl/GrGLCaps.cpp
@@ -344,23 +344,6 @@
      * GrCaps fields
      **************************************************************************/
 
-    // We need dual source blending and the ability to disable multisample in order to support mixed
-    // samples in every corner case. We only use mixed samples if the stencil-and-cover path
-    // renderer is available and enabled; no other path renderers support this feature.
-    if (fMultisampleDisableSupport &&
-        shaderCaps->dualSourceBlendingSupport() &&
-        fShaderCaps->pathRenderingSupport() &&
-        (contextOptions.fGpuPathRenderers & GrContextOptions::GpuPathRenderers::kStencilAndCover)) {
-        fUsesMixedSamples = ctxInfo.hasExtension("GL_NV_framebuffer_mixed_samples") ||
-                ctxInfo.hasExtension("GL_CHROMIUM_framebuffer_mixed_samples");
-        // Workaround NVIDIA bug related to glInvalidateFramebuffer and mixed samples.
-        if (fUsesMixedSamples && (kNVIDIA_GrGLDriver == ctxInfo.driver() ||
-                                  kChromium_GrGLDriver == ctxInfo.driver())) {
-            fDiscardRenderTargetSupport = false;
-            fInvalidateFBType = kNone_InvalidateFBType;
-        }
-    }
-
     // SGX and Mali GPUs that are based on a tiled-deferred architecture that have trouble with
     // frequently changing VBOs. We've measured a performance increase using non-VBO vertex
     // data for dynamic content on these GPUs. Perhaps we should read the renderer string and
@@ -373,11 +356,12 @@
         fPreferClientSideDynamicBuffers = true;
     }
 
-    // fUsesMixedSamples must be set before calling initFSAASupport.
-    this->initFSAASupport(ctxInfo, gli);
+    if (!contextOptions.fAvoidStencilBuffers) {
+        // To reduce surface area, if we avoid stencil buffers, we also disable MSAA.
+        this->initFSAASupport(contextOptions, ctxInfo, gli);
+        this->initStencilSupport(ctxInfo);
+    }
     this->initBlendEqationSupport(ctxInfo);
-    this->initStencilFormats(ctxInfo);
-
 
     if (kGL_GrGLStandard == standard) {
         fMapBufferFlags = kCanMap_MapFlag; // we require VBO support and the desktop VBO
@@ -464,21 +448,6 @@
                            kQualcomm_GrGLVendor != ctxInfo.vendor();
 #endif
 
-    // initFSAASupport() must have been called before this point
-    if (GrGLCaps::kES_IMG_MsToTexture_MSFBOType == fMSFBOType) {
-        GR_GL_GetIntegerv(gli, GR_GL_MAX_SAMPLES_IMG, &fMaxStencilSampleCount);
-    } else if (GrGLCaps::kNone_MSFBOType != fMSFBOType) {
-        GR_GL_GetIntegerv(gli, GR_GL_MAX_SAMPLES, &fMaxStencilSampleCount);
-    }
-    // We only have a use for raster multisample if there is coverage modulation from mixed samples.
-    if (fUsesMixedSamples && ctxInfo.hasExtension("GL_EXT_raster_multisample")) {
-        GR_GL_GetIntegerv(gli, GR_GL_MAX_RASTER_SAMPLES, &fMaxRasterSamples);
-        // This is to guard against platforms that may not support as many samples for
-        // glRasterSamples as they do for framebuffers.
-        fMaxStencilSampleCount = SkTMin(fMaxStencilSampleCount, fMaxRasterSamples);
-    }
-    fMaxColorSampleCount = fMaxStencilSampleCount;
-
     if (ctxInfo.hasExtension("GL_EXT_window_rectangles")) {
         GR_GL_GetIntegerv(gli, GR_GL_MAX_WINDOW_RECTANGLES, &fMaxWindowRectangles);
     }
@@ -982,7 +951,25 @@
            fConfigTable[surfaceConfig].fSecondReadPixelsFormat.fType == readType;
 }
 
-void GrGLCaps::initFSAASupport(const GrGLContextInfo& ctxInfo, const GrGLInterface* gli) {
+void GrGLCaps::initFSAASupport(const GrContextOptions& contextOptions, const GrGLContextInfo& ctxInfo,
+                               const GrGLInterface* gli) {
+    // We need dual source blending and the ability to disable multisample in order to support mixed
+    // samples in every corner case. We only use mixed samples if the stencil-and-cover path
+    // renderer is available and enabled; no other path renderers support this feature.
+    if (fMultisampleDisableSupport &&
+        this->shaderCaps()->dualSourceBlendingSupport() &&
+        this->shaderCaps()->pathRenderingSupport() &&
+        (contextOptions.fGpuPathRenderers & GrContextOptions::GpuPathRenderers::kStencilAndCover)) {
+        fUsesMixedSamples = ctxInfo.hasExtension("GL_NV_framebuffer_mixed_samples") ||
+                ctxInfo.hasExtension("GL_CHROMIUM_framebuffer_mixed_samples");
+        // Workaround NVIDIA bug related to glInvalidateFramebuffer and mixed samples.
+        if (fUsesMixedSamples && (kNVIDIA_GrGLDriver == ctxInfo.driver() ||
+                                  kChromium_GrGLDriver == ctxInfo.driver())) {
+            fDiscardRenderTargetSupport = false;
+            fInvalidateFBType = kNone_InvalidateFBType;
+        }
+    }
+
     if (kGL_GrGLStandard != ctxInfo.standard()) {
         // We prefer the EXT/IMG extension over ES3 MSAA because we've observed
         // ES3 driver bugs on at least one device with a tiled GPU (N10).
@@ -1030,6 +1017,20 @@
             fBlitFramebufferFlags = 0;
         }
     }
+
+    if (GrGLCaps::kES_IMG_MsToTexture_MSFBOType == fMSFBOType) {
+        GR_GL_GetIntegerv(gli, GR_GL_MAX_SAMPLES_IMG, &fMaxStencilSampleCount);
+    } else if (GrGLCaps::kNone_MSFBOType != fMSFBOType) {
+        GR_GL_GetIntegerv(gli, GR_GL_MAX_SAMPLES, &fMaxStencilSampleCount);
+    }
+    // We only have a use for raster multisample if there is coverage modulation from mixed samples.
+    if (fUsesMixedSamples && ctxInfo.hasExtension("GL_EXT_raster_multisample")) {
+        GR_GL_GetIntegerv(gli, GR_GL_MAX_RASTER_SAMPLES, &fMaxRasterSamples);
+        // This is to guard against platforms that may not support as many samples for
+        // glRasterSamples as they do for framebuffers.
+        fMaxStencilSampleCount = SkTMin(fMaxStencilSampleCount, fMaxRasterSamples);
+    }
+    fMaxColorSampleCount = fMaxStencilSampleCount;
 }
 
 void GrGLCaps::initBlendEqationSupport(const GrGLContextInfo& ctxInfo) {
@@ -1084,7 +1085,7 @@
 const GrGLuint kUnknownBitCount = GrGLStencilAttachment::kUnknownBitCount;
 }
 
-void GrGLCaps::initStencilFormats(const GrGLContextInfo& ctxInfo) {
+void GrGLCaps::initStencilSupport(const GrGLContextInfo& ctxInfo) {
 
     // Build up list of legal stencil formats (though perhaps not supported on
     // the particular gpu/driver) from most preferred to least.
diff --git a/src/gpu/gl/GrGLCaps.h b/src/gpu/gl/GrGLCaps.h
index 7439711..c32e419 100644
--- a/src/gpu/gl/GrGLCaps.h
+++ b/src/gpu/gl/GrGLCaps.h
@@ -380,9 +380,10 @@
 
     void onApplyOptionsOverrides(const GrContextOptions& options) override;
 
-    void initFSAASupport(const GrGLContextInfo&, const GrGLInterface*);
+    void initFSAASupport(const GrContextOptions& contextOptions, const GrGLContextInfo&,
+                         const GrGLInterface*);
     void initBlendEqationSupport(const GrGLContextInfo&);
-    void initStencilFormats(const GrGLContextInfo&);
+    void initStencilSupport(const GrGLContextInfo&);
     // This must be called after initFSAASupport().
     void initConfigTable(const GrContextOptions&, const GrGLContextInfo&, const GrGLInterface*,
                          GrShaderCaps*);
diff --git a/src/gpu/gl/GrGLRenderTarget.cpp b/src/gpu/gl/GrGLRenderTarget.cpp
index 45efba2..09c2851 100644
--- a/src/gpu/gl/GrGLRenderTarget.cpp
+++ b/src/gpu/gl/GrGLRenderTarget.cpp
@@ -7,6 +7,7 @@
 
 #include "GrGLRenderTarget.h"
 
+#include "GrContext.h"
 #include "GrGLGpu.h"
 #include "GrGLUtil.h"
 #include "GrGpuResourcePriv.h"
@@ -170,6 +171,10 @@
 }
 
 bool GrGLRenderTarget::canAttemptStencilAttachment() const {
+    if (this->getGpu()->getContext()->caps()->avoidStencilBuffers()) {
+        return false;
+    }
+
     // Only modify the FBO's attachments if we have created the FBO. Public APIs do not currently
     // allow for borrowed FBO ownership, so we can safely assume that if an object is owned,
     // Skia created it.
diff --git a/src/gpu/gl/GrGLTextureRenderTarget.cpp b/src/gpu/gl/GrGLTextureRenderTarget.cpp
index 0abeb8e..eac29b6 100644
--- a/src/gpu/gl/GrGLTextureRenderTarget.cpp
+++ b/src/gpu/gl/GrGLTextureRenderTarget.cpp
@@ -7,6 +7,7 @@
 
 #include "GrGLTextureRenderTarget.h"
 
+#include "GrContext.h"
 #include "SkTraceMemoryDump.h"
 
 // GrGLTextureRenderTarget must dump both of its superclasses.
@@ -40,8 +41,8 @@
 
 bool GrGLTextureRenderTarget::canAttemptStencilAttachment() const {
     // The RT FBO of GrGLTextureRenderTarget is never created from a
-    // wrapped FBO.
-    return true;
+    // wrapped FBO, so we only care about the flag.
+    return !this->getGpu()->getContext()->caps()->avoidStencilBuffers();
 }
 
 sk_sp<GrGLTextureRenderTarget> GrGLTextureRenderTarget::MakeWrapped(
diff --git a/src/gpu/ops/GrAAConvexPathRenderer.cpp b/src/gpu/ops/GrAAConvexPathRenderer.cpp
index f9e95c7..9144d16 100644
--- a/src/gpu/ops/GrAAConvexPathRenderer.cpp
+++ b/src/gpu/ops/GrAAConvexPathRenderer.cpp
@@ -667,9 +667,9 @@
 ///////////////////////////////////////////////////////////////////////////////
 
 bool GrAAConvexPathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const {
-    return (args.fShaderCaps->shaderDerivativeSupport() && (GrAAType::kCoverage == args.fAAType) &&
-            args.fShape->style().isSimpleFill() && !args.fShape->inverseFilled() &&
-            args.fShape->knownToBeConvex());
+    return (args.fCaps->shaderCaps()->shaderDerivativeSupport() &&
+            (GrAAType::kCoverage == args.fAAType) && args.fShape->style().isSimpleFill() &&
+            !args.fShape->inverseFilled() && args.fShape->knownToBeConvex());
 }
 
 // extract the result vertices and indices from the GrAAConvexTessellator
diff --git a/src/gpu/ops/GrAAHairLinePathRenderer.cpp b/src/gpu/ops/GrAAHairLinePathRenderer.cpp
index b8ec966..a40f059 100644
--- a/src/gpu/ops/GrAAHairLinePathRenderer.cpp
+++ b/src/gpu/ops/GrAAHairLinePathRenderer.cpp
@@ -624,7 +624,7 @@
     }
 
     if (SkPath::kLine_SegmentMask == args.fShape->segmentMask() ||
-        args.fShaderCaps->shaderDerivativeSupport()) {
+        args.fCaps->shaderCaps()->shaderDerivativeSupport()) {
         return true;
     }
 
diff --git a/src/gpu/ops/GrDefaultPathRenderer.cpp b/src/gpu/ops/GrDefaultPathRenderer.cpp
index 0ec090e..ef925b6 100644
--- a/src/gpu/ops/GrDefaultPathRenderer.cpp
+++ b/src/gpu/ops/GrDefaultPathRenderer.cpp
@@ -548,10 +548,14 @@
 }
 
 bool GrDefaultPathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const {
+    bool isHairline = IsStrokeHairlineOrEquivalent(args.fShape->style(), *args.fViewMatrix, nullptr);
+    // If we aren't a single_pass_shape or hairline, we require stencil buffers.
+    if (!(single_pass_shape(*args.fShape) || isHairline) && args.fCaps->avoidStencilBuffers()) {
+        return false;
+    }
     // This can draw any path with any simple fill style but doesn't do coverage-based antialiasing.
     return GrAAType::kCoverage != args.fAAType &&
-           (args.fShape->style().isSimpleFill() ||
-            IsStrokeHairlineOrEquivalent(args.fShape->style(), *args.fViewMatrix, nullptr));
+           (args.fShape->style().isSimpleFill() || isHairline);
 }
 
 bool GrDefaultPathRenderer::onDrawPath(const DrawPathArgs& args) {
diff --git a/src/gpu/ops/GrMSAAPathRenderer.cpp b/src/gpu/ops/GrMSAAPathRenderer.cpp
index d4c0f3f..b2782df 100644
--- a/src/gpu/ops/GrMSAAPathRenderer.cpp
+++ b/src/gpu/ops/GrMSAAPathRenderer.cpp
@@ -677,6 +677,10 @@
 }
 
 bool GrMSAAPathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const {
+    // If we aren't a single_pass_shape, we require stencil buffers.
+    if (!single_pass_shape(*args.fShape) && args.fCaps->avoidStencilBuffers()) {
+        return false;
+    }
     // This path renderer only fills and relies on MSAA for antialiasing. Stroked shapes are
     // handled by passing on the original shape and letting the caller compute the stroked shape
     // which will have a fill style.
diff --git a/src/gpu/ops/GrSmallPathRenderer.cpp b/src/gpu/ops/GrSmallPathRenderer.cpp
index 53de779..7b937e5 100644
--- a/src/gpu/ops/GrSmallPathRenderer.cpp
+++ b/src/gpu/ops/GrSmallPathRenderer.cpp
@@ -87,7 +87,7 @@
 
 ////////////////////////////////////////////////////////////////////////////////
 bool GrSmallPathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const {
-    if (!args.fShaderCaps->shaderDerivativeSupport()) {
+    if (!args.fCaps->shaderCaps()->shaderDerivativeSupport()) {
         return false;
     }
     // If the shape has no key then we won't get any reuse.
diff --git a/src/gpu/ops/GrStencilAndCoverPathRenderer.cpp b/src/gpu/ops/GrStencilAndCoverPathRenderer.cpp
index bd5c297..9832359 100644
--- a/src/gpu/ops/GrStencilAndCoverPathRenderer.cpp
+++ b/src/gpu/ops/GrStencilAndCoverPathRenderer.cpp
@@ -22,7 +22,7 @@
 
 GrPathRenderer* GrStencilAndCoverPathRenderer::Create(GrResourceProvider* resourceProvider,
                                                       const GrCaps& caps) {
-    if (caps.shaderCaps()->pathRenderingSupport()) {
+    if (caps.shaderCaps()->pathRenderingSupport() && !caps.avoidStencilBuffers()) {
         return new GrStencilAndCoverPathRenderer(resourceProvider);
     } else {
         return nullptr;