Turned on SkSL->GLSL compiler

src/gpu/gl/builders/GrGLShaderStringBuilder.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrGLShaderStringBuilder.h"
 #include "gl/GrGLGpu.h"
 #include "gl/GrGLSLPrettyPrint.h"
 #include "SkTraceEvent.h"
+#include "SkSLCompiler.h"
+#include "ir/SkSLProgram.h"
 
 #define GL_CALL(X) GR_GL_CALL(gpu->glInterface(), X)
 #define GL_CALL_RET(R, X) GR_GL_CALL_RET(gpu->glInterface(), R, X)
 
 // Print the source code for all shaders generated.
 static const bool c_PrintShaders{false};
 
 static void print_shader_source(const char** strings, int* lengths, int count);
 
+static SkSL::GLCaps skslcaps_for_context(const GrGLContext& context) {
+    GrGLStandard standard = context.standard();
+    const GrGLCaps* caps = context.caps();
+    const GrGLSLCaps* glslCaps = caps->glslCaps();
+    SkSL::GLCaps result;
+    switch (standard) {
+        case kGL_GrGLStandard:
+            result.fStandard = SkSL::GLCaps::kGL_Standard;
+            break;
+        case kGLES_GrGLStandard:
+            result.fStandard = SkSL::GLCaps::kGLES_Standard;
+            break;
+        default:
+            SkASSERT(false);
+            result.fStandard = SkSL::GLCaps::kGL_Standard;
+    }
+
+    switch (glslCaps->generation()) {
+        case k110_GrGLSLGeneration:
+            if (kGLES_GrGLStandard == standard) {
+                // ES2's shader language is based on GLSL 1.20 but is version 1.00 of the ES 
+                // language
+                result.fVersion = 100;
+            } else {
+                SkASSERT(kGL_GrGLStandard == standard);
+                result.fVersion = 110;
+            }
+            break;
+        case k130_GrGLSLGeneration:
+            SkASSERT(kGL_GrGLStandard == standard);
+            result.fVersion = 130;
+            break;
+        case k140_GrGLSLGeneration:
+            SkASSERT(kGL_GrGLStandard == standard);
+            result.fVersion = 140;
+            break;
+        case k150_GrGLSLGeneration:
+            SkASSERT(kGL_GrGLStandard == standard);
+            result.fVersion = 150;
+            break;
+        case k330_GrGLSLGeneration:
+            if (kGLES_GrGLStandard == standard) {
+                result.fVersion = 300;
+            } else {
+                SkASSERT(kGL_GrGLStandard == standard);
+                result.fVersion = 330;
+            }
+            break;
+        case k400_GrGLSLGeneration:
+            SkASSERT(kGL_GrGLStandard == standard);
+            result.fVersion = 400;
+            break;
+        case k310es_GrGLSLGeneration:
+            SkASSERT(kGLES_GrGLStandard == standard);
+            result.fVersion = 310;
+            break;
+        case k320es_GrGLSLGeneration:
+            SkASSERT(kGLES_GrGLStandard == standard);
+            result.fVersion = 320;
+            break;
+    }
+    result.fIsCoreProfile = caps->isCoreProfile();
+    result.fUsesPrecisionModifiers = glslCaps->usesPrecisionModifiers();
+    result.fMustDeclareFragmentShaderOutput = glslCaps->mustDeclareFragmentShaderOutput();
+    result.fCanUseMinAndAbsTogether = glslCaps->canUseMinAndAbsTogether();
+    return result;
+}
+
+static void dump_string(std::string s) {
+    // on Android, SkDebugf only displays the first 1K characters of output, which results in
+    // incomplete shader source code. Print each line individually to avoid this problem.
+    size_t index = 0;
+    for (;;) {
+        size_t next = s.find("\n", index);
+        if (next == std::string::npos) {
+            SkDebugf("%s", s.substr(index).c_str());
+            break;
+        } else {
+            SkDebugf("%s", s.substr(index, next - index + 1).c_str());
+            index = next + 1;
+        }
+    }
+}
+
 GrGLuint GrGLCompileAndAttachShader(const GrGLContext& glCtx,
                                     GrGLuint programId,
                                     GrGLenum type,
                                     const char** strings,
                                     int* lengths,
                                     int count,
                                     GrGpu::Stats* stats) {
     const GrGLInterface* gli = glCtx.interface();
 
     GrGLuint shaderId;
     GR_GL_CALL_RET(gli, shaderId, CreateShader(type));
     if (0 == shaderId) {
         return 0;
     }
 
+    std::string sksl;
 #ifdef SK_DEBUG
     SkString prettySource = GrGLSLPrettyPrint::PrettyPrintGLSL(strings, lengths, count, false);
-    const GrGLchar* sourceStr = prettySource.c_str();
-    GrGLint sourceLength = static_cast<GrGLint>(prettySource.size());
-    GR_GL_CALL(gli, ShaderSource(shaderId, 1, &sourceStr, &sourceLength));
+    sksl = std::string(prettySource.c_str());
 #else
-    GR_GL_CALL(gli, ShaderSource(shaderId, count, strings, lengths));
+    for (int i = 0; i < count; i++) {
+        sksl.append(strings[i], lengths[i]);
+    }
 #endif
 
+    std::string glsl;
+    SkSL::Compiler& compiler = *glCtx.compiler();
+    SkSL::GLCaps caps = skslcaps_for_context(glCtx);
+    SkASSERT(type == GR_GL_VERTEX_SHADER || type == GR_GL_FRAGMENT_SHADER);
+    SkDEBUGCODE(bool result = )compiler.toGLSL(type == GR_GL_VERTEX_SHADER 
+                                                                    ? SkSL::Program::kVertex_Kind
+                                                                    : SkSL::Program::kFragment_Kind,
+                                               std::string(sksl.c_str()),
+                                               caps,
+                                               &glsl);
+#ifdef SK_DEBUG
+    if (!result) {
+        SkDebugf("SKSL compilation error\n----------------------\n");
+        SkDebugf("SKSL:\n");
+        dump_string(sksl);
+        SkDebugf("\nErrors:\n%s\n", compiler.errorText().c_str());
+        SkDEBUGFAIL("SKSL compilation failed!\n");
+    }
+#endif
+    const char* glslChars = glsl.c_str();
+    GrGLint glslLength = (GrGLint) glsl.length();
+    GR_GL_CALL(gli, ShaderSource(shaderId, 1, &glslChars, &glslLength));
+
     // If tracing is enabled in chrome then we pretty print
     bool traceShader;
     TRACE_EVENT_CATEGORY_GROUP_ENABLED(TRACE_DISABLED_BY_DEFAULT("skia.gpu"), &traceShader);
     if (traceShader) {
         SkString shader = GrGLSLPrettyPrint::PrettyPrintGLSL(strings, lengths, count, false);
         TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("skia.gpu"), "skia_gpu::GLShader",
                              TRACE_EVENT_SCOPE_THREAD, "shader", TRACE_STR_COPY(shader.c_str()));
     }
 
     stats->incShaderCompilations();
@@ skipping 10 matching lines @@
 
         if (!compiled) {
             GrGLint infoLen = GR_GL_INIT_ZERO;
             GR_GL_CALL(gli, GetShaderiv(shaderId, GR_GL_INFO_LOG_LENGTH, &infoLen));
             SkAutoMalloc log(sizeof(char)*(infoLen+1)); // outside if for debugger
             if (infoLen > 0) {
                 // 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()));
-                print_shader_source(strings, lengths, count);
-                SkDebugf("\n%s", (const char*)log.get());
+                SkDebugf("GLSL compilation error\n----------------------\n");
+                SkDebugf("SKSL:\n");
+                dump_string(sksl);
+                SkDebugf("GLSL:\n");
+                dump_string(glsl);
+                SkDebugf("Errors:\n%s\n", (const char*) log.get());
             }
-            SkDEBUGFAIL("Shader compilation failed!");
+            SkDEBUGFAIL("GLSL compilation failed!");
             GR_GL_CALL(gli, DeleteShader(shaderId));
             return 0;
         }
     }
 
     if (c_PrintShaders) {
         print_shader_source(strings, lengths, count);
     }
 
     // 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));
 
     return shaderId;
 }
 
 static void print_shader_source(const char** strings, int* lengths, int count) {
     const SkString& pretty = GrGLSLPrettyPrint::PrettyPrintGLSL(strings, lengths, count, true);
     SkTArray<SkString> lines;
     SkStrSplit(pretty.c_str(), "\n", &lines);
     for (const SkString& line : lines) {
         // Print the shader one line at the time so it doesn't get truncated by the adb log.
         SkDebugf("%s\n", line.c_str());
     }
 }