initial checkin of SkSL compiler

src/sksl/ir/SkSLTernaryExpression.h

+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+ 
+#ifndef SKSL_TERNARYEXPRESSION
+#define SKSL_TERNARYEXPRESSION
+
+#include "SkSLExpression.h"
+#include "../SkSLPosition.h"
+
+namespace SkSL {
+
+/**
+ * A ternary expression (test ? ifTrue : ifFalse).
+ */
+struct TernaryExpression : public Expression {
+    TernaryExpression(Position position, std::unique_ptr<Expression> test,
+                      std::unique_ptr<Expression> ifTrue, std::unique_ptr<Expression> ifFalse)
+    : INHERITED(position, kTernary_Kind, ifTrue->fType)
+    , fTest(std::move(test))
+    , fIfTrue(std::move(ifTrue))
+    , fIfFalse(std::move(ifFalse)) {
+        ASSERT(fIfTrue->fType == fIfFalse->fType);
+    }
+
+    std::string description() const override {
+        return "(" + fTest->description() + " ? " + fIfTrue->description() + " : " + 
+               fIfFalse->description() + ")";
+    }
+
+    const std::unique_ptr<Expression> fTest;
+    const std::unique_ptr<Expression> fIfTrue;
+    const std::unique_ptr<Expression> fIfFalse;
+
+    typedef Expression INHERITED;
+};
+
+} // namespace
+
+#endif