initial SkSLJIT checkin

Docs-Preview: https://skia.org/?cl=112204
Bug: skia:
Change-Id: I10042a0200db00bd8ff8078467c409b1cf191f50
Reviewed-on: https://skia-review.googlesource.com/112204
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>

1 files changed, 89 insertions, 0 deletions

diff --git a/src/sksl/SkSLInterpreter.h b/src/sksl/SkSLInterpreter.h
new file mode 100644
index 0000000000..93f32a1617
--- /dev/null
+++ b/src/sksl/SkSLInterpreter.h
@@ -0,0 +1,89 @@
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SKSL_INTERPRETER
+#define SKSL_INTERPRETER
+
+#include "ir/SkSLAppendStage.h"
+#include "ir/SkSLExpression.h"
+#include "ir/SkSLFunctionCall.h"
+#include "ir/SkSLFunctionDefinition.h"
+#include "ir/SkSLProgram.h"
+#include "ir/SkSLStatement.h"
+
+#include <stack>
+
+class SkRasterPipeline;
+
+namespace SkSL {
+
+class Interpreter {
+    typedef int StackIndex;
+
+    struct StatementIndex {
+        const Statement* fStatement;
+        size_t fIndex;
+    };
+
+public:
+    union Value {
+        Value(float f)
+        : fFloat(f) {}
+
+        Value(int i)
+        : fInt(i) {}
+
+        Value(bool b)
+        : fBool(b) {}
+
+        float fFloat;
+        int fInt;
+        bool fBool;
+    };
+
+    enum TypeKind {
+        kFloat_TypeKind,
+        kInt_TypeKind,
+        kBool_TypeKind
+    };
+
+    Interpreter(std::unique_ptr<Program> program, SkRasterPipeline* pipeline, std::vector<Value>* stack)
+    : fProgram(std::move(program))
+    , fPipeline(*pipeline)
+    , fStack(*stack) {}
+
+    void run();
+
+    void run(const FunctionDefinition& f);
+
+    void push(Value value);
+
+    Value pop();
+
+    StackIndex stackAlloc(int count);
+
+    void runStatement();
+
+    StackIndex getLValue(const Expression& expr);
+
+    Value call(const FunctionCall& c);
+
+    void appendStage(const AppendStage& c);
+
+    Value evaluate(const Expression& expr);
+
+private:
+    std::unique_ptr<Program> fProgram;
+    SkRasterPipeline& fPipeline;
+    std::vector<StatementIndex> fCurrentIndex;
+    std::vector<std::map<const Variable*, StackIndex>> fVars;
+    std::vector<Value> &fStack;
+};
+
+} // namespace
+
+#endif