initial checkin of SkSL compiler

src/sksl/SkSLCompiler.cpp

Index: src/sksl/SkSLCompiler.cpp
diff --git a/src/sksl/SkSLCompiler.cpp b/src/sksl/SkSLCompiler.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..6f443fd91d4ad0cbb3efdc7ea650742c29e1be45
--- /dev/null
+++ b/src/sksl/SkSLCompiler.cpp
@@ -0,0 +1,255 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+ 
+#include "SkSLCompiler.h"
+
+#include <fstream>
+#include <streambuf>
+
+#include "SkSLIRGenerator.h"
+#include "SkSLParser.h"
+#include "SkSLSPIRVCodeGenerator.h"
+#include "ir/SkSLExpression.h"
+#include "ir/SkSLIntLiteral.h"
+#include "ir/SkSLSymbolTable.h"
+#include "ir/SkSLVarDeclaration.h"
+#include "SkMutex.h"
+
+#define STRINGIFY(x) #x
+
+// include the built-in shader symbols as static strings
+
+static std::string SKSL_INCLUDE = 
+#include "sksl.include"
+;
+
+static std::string SKSL_VERT_INCLUDE = 
+#include "sksl_vert.include"
+;
+
+static std::string SKSL_FRAG_INCLUDE = 
+#include "sksl_frag.include"
+;
+
+namespace SkSL {
+
+Compiler::Compiler() 
+: fErrorCount(0) {
+#ifdef SKIA
+    SK_DECLARE_STATIC_MUTEX(mutex);
+    mutex.acquire();
+    static bool initialized = false;
+    static auto types = std::shared_ptr<SymbolTable>(new SymbolTable(*this));

[dogben, 2016/06/23 17:43:11]

This seems unhygienic. Could we either add a dummy implementation of
ErrorReporter and store it in a static field, or make SymbolTable handle a null
ErrorReporter?

[ethannicholas, 2016/06/24 21:23:08]

These didn't used to be shared, and I failed to fix this when I made them
static. Fixed.

+    static auto symbols = std::shared_ptr<SymbolTable>(new SymbolTable(types, *this));

[dogben, 2016/06/23 17:43:12]

Why are types and symbols in different SymbolTables?

[ethannicholas, 2016/06/24 21:23:08]

The Parser uses the types symboltable to determine whether an IDENTIFIER is a
type. I've added a comment to clarify that.

+    fIRGenerator = new IRGenerator(symbols, *this);
+    fTypes = types;
+    if (!initialized) {
+#else
+    auto types = std::shared_ptr<SymbolTable>(new SymbolTable(*this));
+    auto symbols = std::shared_ptr<SymbolTable>(new SymbolTable(types, *this));
+    fIRGenerator = new IRGenerator(symbols, *this);
+    fTypes = types;
+#endif
+        #define ADD_TYPE(t) types->add(k ## t ## _Type->fName, k ## t ## _Type)
+        ADD_TYPE(Void);
+        ADD_TYPE(Float);
+        ADD_TYPE(Vec2);
+        ADD_TYPE(Vec3);
+        ADD_TYPE(Vec4);
+        ADD_TYPE(Double);
+        ADD_TYPE(DVec2);
+        ADD_TYPE(DVec3);
+        ADD_TYPE(DVec4);
+        ADD_TYPE(Int);
+        ADD_TYPE(IVec2);
+        ADD_TYPE(IVec3);
+        ADD_TYPE(IVec4);
+        ADD_TYPE(UInt);
+        ADD_TYPE(UVec2);
+        ADD_TYPE(UVec3);
+        ADD_TYPE(UVec4);
+        ADD_TYPE(Bool);
+        ADD_TYPE(BVec2);
+        ADD_TYPE(BVec3);
+        ADD_TYPE(BVec4);
+        ADD_TYPE(Mat2x2);
+        ADD_TYPE(Mat2x3);
+        ADD_TYPE(Mat2x4);
+        ADD_TYPE(Mat3x2);
+        ADD_TYPE(Mat3x3);
+        ADD_TYPE(Mat3x4);
+        ADD_TYPE(Mat4x2);
+        ADD_TYPE(Mat4x3);
+        ADD_TYPE(Mat4x4);
+        ADD_TYPE(GenType);
+        ADD_TYPE(GenDType);
+        ADD_TYPE(GenIType);
+        ADD_TYPE(GenUType);
+        ADD_TYPE(GenBType);
+        ADD_TYPE(Mat);
+        ADD_TYPE(Vec);
+        ADD_TYPE(GVec);
+        ADD_TYPE(GVec2);
+        ADD_TYPE(GVec3);
+        ADD_TYPE(GVec4);
+        ADD_TYPE(DVec);
+        ADD_TYPE(IVec);
+        ADD_TYPE(UVec);
+        ADD_TYPE(BVec);
+
+        ADD_TYPE(Sampler1D);
+        ADD_TYPE(Sampler2D);
+        ADD_TYPE(Sampler3D);
+        ADD_TYPE(SamplerCube);
+        ADD_TYPE(Sampler2DRect);
+        ADD_TYPE(Sampler1DArray);
+        ADD_TYPE(Sampler2DArray);
+        ADD_TYPE(SamplerCubeArray);
+        ADD_TYPE(SamplerBuffer);
+        ADD_TYPE(Sampler2DMS);
+        ADD_TYPE(Sampler2DMSArray);
+
+        ADD_TYPE(GSampler1D);
+        ADD_TYPE(GSampler2D);
+        ADD_TYPE(GSampler3D);
+        ADD_TYPE(GSamplerCube);
+        ADD_TYPE(GSampler2DRect);
+        ADD_TYPE(GSampler1DArray);
+        ADD_TYPE(GSampler2DArray);
+        ADD_TYPE(GSamplerCubeArray);
+        ADD_TYPE(GSamplerBuffer);
+        ADD_TYPE(GSampler2DMS);
+        ADD_TYPE(GSampler2DMSArray);
+
+        ADD_TYPE(Sampler1DShadow);
+        ADD_TYPE(Sampler2DShadow);
+        ADD_TYPE(SamplerCubeShadow);
+        ADD_TYPE(Sampler2DRectShadow);
+        ADD_TYPE(Sampler1DArrayShadow);
+        ADD_TYPE(Sampler2DArrayShadow);
+        ADD_TYPE(SamplerCubeArrayShadow);
+        ADD_TYPE(GSampler2DArrayShadow);
+        ADD_TYPE(GSamplerCubeArrayShadow);
+
+        std::vector<std::unique_ptr<ProgramElement>> ignored;
+        ASSERT_RESULT(this->internalConvertProgram(SKSL_INCLUDE, &ignored));
+#ifdef SKIA
+        initialized = true;
+    }
+    mutex.release();
+#endif
+}
+
+Compiler::~Compiler() {
+    delete fIRGenerator;
+}
+
+bool Compiler::internalConvertProgram(std::string text,
+                                      std::vector<std::unique_ptr<ProgramElement>>* result) {
+    Parser parser(text, *fTypes, *this);
+    std::vector<std::unique_ptr<ASTDeclaration>> parsed = parser.file();
+    for (size_t i = 0; i < parsed.size(); i++) {
+        ASTDeclaration& decl = *parsed[i];
+        switch (decl.fKind) {
+            case ASTDeclaration::kVar_Kind: {
+                std::unique_ptr<VarDeclaration> s = fIRGenerator->convertVarDeclaration(
+                                                                         (ASTVarDeclaration&) decl, 

[dogben, 2016/06/23 17:43:11]

nit: odd indentation, several places in this method

+                                                                         Variable::kGlobal_Storage);
+                if (s) {
+                    result->push_back(std::move(s));
+                }
+                break;
+            }
+            case ASTDeclaration::kFunction_Kind: {
+                std::unique_ptr<FunctionDefinition> f = fIRGenerator->convertFunction(
+                                                                               (ASTFunction&) decl);
+                if (f) {
+                    result->push_back(std::move(f));
+                }
+                break;
+            }
+            case ASTDeclaration::kInterfaceBlock_Kind: {
+                std::unique_ptr<InterfaceBlock> i = fIRGenerator->convertInterfaceBlock(
+                                                                         (ASTInterfaceBlock&) decl);
+                if (i) {
+                    result->push_back(std::move(i));
+                }
+                break;
+            }
+            case ASTDeclaration::kExtension_Kind: {
+                std::unique_ptr<Extension> e = fIRGenerator->convertExtension((ASTExtension&) decl);
+                if (e) {
+                    result->push_back(std::move(e));
+                }
+                break;
+            }
+            default:
+                ABORT("unsupported declaration: %s\n", decl.description().c_str());
+        }
+    }
+    return true;

[dogben, 2016/06/23 17:43:11]

return fErrorCount == 0? Or make return type void?

+}
+
+std::unique_ptr<Program> Compiler::convertProgram(Program::Kind kind, std::string text) {
+    fErrorText = "";
+    fErrorCount = 0;
+    fIRGenerator->pushSymbolTable();
+    std::vector<std::unique_ptr<ProgramElement>> result;
+    switch (kind) {
+        case Program::kVertex_Kind:
+            this->internalConvertProgram(SKSL_VERT_INCLUDE, &result);
+            break;
+        case Program::kFragment_Kind:
+            this->internalConvertProgram(SKSL_FRAG_INCLUDE, &result);
+            break;
+    }
+    this->internalConvertProgram(text, &result);
+    fIRGenerator->popSymbolTable();
+    this->writeErrorCount();
+    return std::unique_ptr<Program>(new Program(kind, std::move(result)));;
+}
+
+void Compiler::error(Position position, std::string msg) {
+    fErrorCount++;
+    fErrorText += "error: " + position.description() + ": " + msg.c_str() + "\n";
+}
+
+std::string Compiler::errorText() {
+    std::string result = fErrorText;

[dogben, 2016/06/23 17:43:11]

nit: "return fErrorText;" is equivalent.

+    return result;
+}
+
+void Compiler::writeErrorCount() {
+    if (fErrorCount) {
+        fErrorText += to_string(fErrorCount) + " error";
+        if (fErrorCount > 1) {
+            fErrorText += "s";
+        }
+        fErrorText += "\n";
+    }
+}
+
+bool Compiler::toSPIRV(Program::Kind kind, std::string text, std::ostream& out) {
+    auto program = this->convertProgram(kind, text);
+    if (fErrorCount == 0) {
+        auto cg = std::unique_ptr<SkSL::CodeGenerator>(new SkSL::SPIRVCodeGenerator());
+        cg->generateCode(*program.get(), out);

[dogben, 2016/06/23 17:43:11]

nit: ".get()" is unnecessary

+        ASSERT(!out.rdstate());

[dogben, 2016/06/23 17:43:11]

nit: caller's responsibility to check this, and errors writing to a file
shouldn't crash the program.

This would make more sense in the next method, ASSERT(!buffer.rdstate());

+    }
+    return fErrorCount == 0;
+}
+
+bool Compiler::toSPIRV(Program::Kind kind, std::string text, std::string* out) {
+    std::stringstream buffer;
+    bool result = this->toSPIRV(kind, text, buffer);
+    if (result) {
+        *out = buffer.str();
+    }
+    return fErrorCount == 0;
+}
+
+} // namespace