initial checkin of SkSL compiler

src/sksl/ir/SkSLStatement.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_STATEMENT
+#define SKSL_STATEMENT
+
+#include "SkSLIRNode.h"
+#include "SkSLType.h"
+
+namespace SkSL {
+
+/**
+ * Abstract supertype of all statements.
+ */
+struct Statement : public IRNode {
+    enum Kind {
+        kBlock_Kind,
+        kBreak_Kind,
+        kContinue_Kind,
+        kDiscard_Kind,
+        kDo_Kind,
+        kExpression_Kind,
+        kFor_Kind,
+        kIf_Kind,
+        kReturn_Kind,
+        kVarDeclaration_Kind,
+        kWhile_Kind
+    };
+
+    Statement(Position position, Kind kind)
+    : INHERITED(position)
+    , fKind(kind) {}
+
+    const Kind fKind;
+
+    typedef IRNode INHERITED;
+};
+
+} // namespace
+
+#endif