Revert "Revert "Make SkSL GLSL generator declare sk_FragColor inout when EXT fb fetch is used.""

This reverts commit d40133092ae138b3d47a1158101faec3c53c6b1f.

Bug: skia:
Change-Id: I236505da047d5ad29e4952d8955eb7aa1bfb870b
Reviewed-on: https://skia-review.googlesource.com/118621
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

3 files changed, 8 insertions, 0 deletions

diff --git a/src/gpu/glsl/GrGLSLFragmentShaderBuilder.cpp b/src/gpu/glsl/GrGLSLFragmentShaderBuilder.cpp
index 8ad3a058eb..9afd470776 100644
--- a/src/gpu/glsl/GrGLSLFragmentShaderBuilder.cpp
+++ b/src/gpu/glsl/GrGLSLFragmentShaderBuilder.cpp
@@ -170,6 +170,11 @@ const char* GrGLSLFragmentShaderBuilder::getPrimaryColorOutputName() const {
     return fHasCustomColorOutput ? DeclaredColorOutputName() : "sk_FragColor";
 }
 
+bool GrGLSLFragmentShaderBuilder::primaryColorOutputIsInOut() const {
+    return fHasCustomColorOutput &&
+           fOutputs[fCustomColorOutputIndex].getTypeModifier() == GrShaderVar::kInOut_TypeModifier;
+}
+
 void GrGLSLFragmentBuilder::declAppendf(const char* fmt, ...) {
     va_list argp;
     va_start(argp, fmt);
diff --git a/src/gpu/glsl/GrGLSLFragmentShaderBuilder.h b/src/gpu/glsl/GrGLSLFragmentShaderBuilder.h
index 5a73c17d9a..0e0794fd37 100644
--- a/src/gpu/glsl/GrGLSLFragmentShaderBuilder.h
+++ b/src/gpu/glsl/GrGLSLFragmentShaderBuilder.h
@@ -119,6 +119,7 @@ private:
     void enableSecondaryOutput();
     const char* getPrimaryColorOutputName() const;
     const char* getSecondaryColorOutputName() const;
+    bool primaryColorOutputIsInOut() const;
 
 #ifdef SK_DEBUG
     // As GLSLProcessors emit code, there are some conditions we need to verify.  We use the below
diff --git a/src/gpu/glsl/GrGLSLProgramBuilder.h b/src/gpu/glsl/GrGLSLProgramBuilder.h
index ac2d4965b5..d4d2099a41 100644
--- a/src/gpu/glsl/GrGLSLProgramBuilder.h
+++ b/src/gpu/glsl/GrGLSLProgramBuilder.h
@@ -115,6 +115,8 @@ protected:
 
     void finalizeShaders();
 
+    bool fragColorIsInOut() const { return fFS.primaryColorOutputIsInOut(); }
+
 private:
     // reset is called by program creator between each processor's emit code.  It increments the
     // stage offset for variable name mangling, and also ensures verfication variables in the