Defer deletion of our shaders until after linking the gl program to work around an Android emulator…

src/gpu/gl/GrGLShaderBuilder.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gl/GrGLShaderBuilder.h"
 #include "gl/GrGLProgram.h"
 #include "gl/GrGLUniformHandle.h"
@@ skipping 554 matching lines @@
 const char* GrGLShaderBuilder::enableSecondaryOutput() {
     if (!fHasSecondaryOutput) {
         fFSOutputs.push_back().set(kVec4f_GrSLType,
                                    GrGLShaderVar::kOut_TypeModifier,
                                    dual_source_output_name());
         fHasSecondaryOutput = true;
     }
     return dual_source_output_name();
 }
 
-
 bool GrGLShaderBuilder::finish(GrGLuint* outProgramId) {
     SK_TRACE_EVENT0("GrGLShaderBuilder::finish");
 
     GrGLuint programId = 0;
     GL_CALL_RET(programId, CreateProgram());
     if (!programId) {
         return false;
     }
 
-    if (!this->compileAndAttachShaders(programId)) {
+    SkTDArray<GrGLuint> shadersToDelete;
+
+    if (!this->compileAndAttachShaders(programId, &shadersToDelete)) {
         GL_CALL(DeleteProgram(programId));
         return false;
     }
 
     this->bindProgramLocations(programId);
     if (fUniformManager.isUsingBindUniform()) {
       fUniformManager.getUniformLocations(programId, fUniforms);
     }
 
     GL_CALL(LinkProgram(programId));
@@ skipping 22 matching lines @@
             }
             SkDEBUGFAIL("Error linking program");
             GL_CALL(DeleteProgram(programId));
             return false;
         }
     }
 
     if (!fUniformManager.isUsingBindUniform()) {
       fUniformManager.getUniformLocations(programId, fUniforms);
     }
+
+    for (int i = 0; i < shadersToDelete.count(); ++i) {
+      GL_CALL(DeleteShader(shadersToDelete[i]));
+    }
+
     *outProgramId = programId;
     return true;
 }
 
-// Compiles a GL shader, attaches it to a program, and releases the shader's reference.
-// (That way there's no need to hang on to the GL shader id and delete it later.)
-static bool attach_shader(const GrGLContext& glCtx,
-                          GrGLuint programId,
-                          GrGLenum type,
-                          const SkString& shaderSrc) {
+// Compiles a GL shader and attaches it to a program. Returns the shader ID if
+// successful, or 0 if not.
+static GrGLuint attach_shader(const GrGLContext& glCtx,
+                              GrGLuint programId,
+                              GrGLenum type,
+                              const SkString& shaderSrc) {
     const GrGLInterface* gli = glCtx.interface();
 
     GrGLuint shaderId;
     GR_GL_CALL_RET(gli, shaderId, CreateShader(type));
     if (0 == shaderId) {
-        return false;
+        return 0;
     }
 
     const GrGLchar* sourceStr = shaderSrc.c_str();
     GrGLint sourceLength = static_cast<GrGLint>(shaderSrc.size());
     GR_GL_CALL(gli, ShaderSource(shaderId, 1, &sourceStr, &sourceLength));
     GR_GL_CALL(gli, CompileShader(shaderId));
 
     // Calling GetShaderiv in Chromium is quite expensive. Assume success in release builds.
     bool checkCompiled = !glCtx.isChromium();
 #ifdef SK_DEBUG
@@ skipping 11 matching lines @@
                 // retrieve length even though we don't need it to workaround bug in Chromium cmd
                 // buffer param validation.
                 GrGLsizei length = GR_GL_INIT_ZERO;
                 GR_GL_CALL(gli, GetShaderInfoLog(shaderId, infoLen+1,
                                                  &length, (char*)log.get()));
                 GrPrintf(shaderSrc.c_str());
                 GrPrintf("\n%s", log.get());
             }
             SkDEBUGFAIL("Shader compilation failed!");
             GR_GL_CALL(gli, DeleteShader(shaderId));
-            return false;
+            return 0;
         }
     }
     if (c_PrintShaders) {
         GrPrintf(shaderSrc.c_str());
         GrPrintf("\n");
     }
 
+    // Attach the shader, but defer deletion until after we have linked the program.
+    // This works around a bug in the Android emulator's GLES2 wrapper which
+    // will immediately delete the shader object and free its memory even though it's
+    // attached to a program, which then causes glLinkProgram to fail.
     GR_GL_CALL(gli, AttachShader(programId, shaderId));
-    GR_GL_CALL(gli, DeleteShader(shaderId));
-    return true;
+
+    return shaderId;
 }
 
-bool GrGLShaderBuilder::compileAndAttachShaders(GrGLuint programId) const {
+bool GrGLShaderBuilder::compileAndAttachShaders(GrGLuint programId, SkTDArray<GrGLuint>* shaderIds) const {
     SkString fragShaderSrc(GrGetGLSLVersionDecl(this->ctxInfo()));
     fragShaderSrc.append(fFSExtensions);
     append_default_precision_qualifier(kDefaultFragmentPrecision,
                                        fGpu->glStandard(),
                                        &fragShaderSrc);
     this->appendUniformDecls(kFragment_Visibility, &fragShaderSrc);
     this->appendDecls(fFSInputs, &fragShaderSrc);
     // We shouldn't have declared outputs on 1.10
     SkASSERT(k110_GrGLSLGeneration != fGpu->glslGeneration() || fFSOutputs.empty());
     this->appendDecls(fFSOutputs, &fragShaderSrc);
     fragShaderSrc.append(fFSFunctions);
     fragShaderSrc.append("void main() {\n");
     fragShaderSrc.append(fFSCode);
     fragShaderSrc.append("}\n");
-    if (!attach_shader(fGpu->glContext(), programId, GR_GL_FRAGMENT_SHADER, fragShaderSrc)) {
+
+    GrGLuint fragShaderId = attach_shader(fGpu->glContext(), programId, GR_GL_FRAGMENT_SHADER, fragShaderSrc);
+    if (!fragShaderId) {
         return false;
     }
 
+    *shaderIds->append() = fragShaderId;
+
     return true;
 }
 
 void GrGLShaderBuilder::bindProgramLocations(GrGLuint programId) const {
     if (fHasCustomColorOutput) {
         GL_CALL(BindFragDataLocation(programId, 0, declared_color_output_name()));
     }
     if (fHasSecondaryOutput) {
         GL_CALL(BindFragDataLocationIndexed(programId, 0, 1, dual_source_output_name()));
     }
@@ skipping 146 matching lines @@
 
     GrGLVertexProgramEffectsBuilder programEffectsBuilder(this, effectCnt);
     this->INHERITED::createAndEmitEffects(&programEffectsBuilder,
                                           effectStages,
                                           effectKeys,
                                           effectCnt,
                                           inOutFSColor);
     return programEffectsBuilder.finish();
 }
 
-bool GrGLFullShaderBuilder::compileAndAttachShaders(GrGLuint programId) const {
+bool GrGLFullShaderBuilder::compileAndAttachShaders(GrGLuint programId, SkTDArray<GrGLuint>* shaderIds) const {
     const GrGLContext& glCtx = this->gpu()->glContext();
     SkString vertShaderSrc(GrGetGLSLVersionDecl(this->ctxInfo()));
     this->appendUniformDecls(kVertex_Visibility, &vertShaderSrc);
     this->appendDecls(fVSAttrs, &vertShaderSrc);
     this->appendDecls(fVSOutputs, &vertShaderSrc);
     vertShaderSrc.append("void main() {\n");
     vertShaderSrc.append(fVSCode);
     vertShaderSrc.append("}\n");
-    if (!attach_shader(glCtx, programId, GR_GL_VERTEX_SHADER, vertShaderSrc)) {
+    GrGLuint vertShaderId = attach_shader(glCtx, programId, GR_GL_VERTEX_SHADER, vertShaderSrc);
+    if (!vertShaderId) {
         return false;
     }
+    *shaderIds->append() = vertShaderId;
 
 #if GR_GL_EXPERIMENTAL_GS
     if (fDesc.getHeader().fExperimentalGS) {
         SkASSERT(this->ctxInfo().glslGeneration() >= k150_GrGLSLGeneration);
         SkString geomShaderSrc(GrGetGLSLVersionDecl(this->ctxInfo()));
         geomShaderSrc.append("layout(triangles) in;\n"
                              "layout(triangle_strip, max_vertices = 6) out;\n");
         this->appendDecls(fGSInputs, &geomShaderSrc);
         this->appendDecls(fGSOutputs, &geomShaderSrc);
         geomShaderSrc.append("void main() {\n");
         geomShaderSrc.append("\tfor (int i = 0; i < 3; ++i) {\n"
                              "\t\tgl_Position = gl_in[i].gl_Position;\n");
         if (fDesc.getHeader().fEmitsPointSize) {
             geomShaderSrc.append("\t\tgl_PointSize = 1.0;\n");
         }
         SkASSERT(fGSInputs.count() == fGSOutputs.count());
         for (int i = 0; i < fGSInputs.count(); ++i) {
             geomShaderSrc.appendf("\t\t%s = %s[i];\n",
                                   fGSOutputs[i].getName().c_str(),
                                   fGSInputs[i].getName().c_str());
         }
         geomShaderSrc.append("\t\tEmitVertex();\n"
                              "\t}\n"
                              "\tEndPrimitive();\n");
         geomShaderSrc.append("}\n");
-        if (!attach_shader(glCtx, programId, GR_GL_GEOMETRY_SHADER, geomShaderSrc)) {
+        GrGLuint geomShaderId = attach_shader(glCtx, programId, GR_GL_GEOMETRY_SHADER, geomShaderSrc);
+        if (!geomShaderId) {
             return false;
         }
+        *shaderIds->append() = geomShaderId;
     }
 #endif
 
-    return this->INHERITED::compileAndAttachShaders(programId);
+    return this->INHERITED::compileAndAttachShaders(programId, shaderIds);
 }
 
 void GrGLFullShaderBuilder::bindProgramLocations(GrGLuint programId) const {
     this->INHERITED::bindProgramLocations(programId);
 
     const GrGLProgramDesc::KeyHeader& header = fDesc.getHeader();
 
     // Bind the attrib locations to same values for all shaders
     SkASSERT(-1 != header.fPositionAttributeIndex);
     GL_CALL(BindAttribLocation(programId,
@@ skipping 50 matching lines @@
         GrGLSLExpr4* inOutFSColor) {
 
     GrGLTexGenProgramEffectsBuilder texGenEffectsBuilder(this, effectCnt);
     this->INHERITED::createAndEmitEffects(&texGenEffectsBuilder,
                                           effectStages,
                                           effectKeys,
                                           effectCnt,
                                           inOutFSColor);
     return texGenEffectsBuilder.finish();
 }