Re-re-land "added GrSkSLFP and converted DitherEffect to use it"

This reverts commit 6c48e4d11ce80fa5cfef56e13b2d5847fe94a7cc.

Bug: skia:
Change-Id: I7ee78990fc30eec545d1856e59eb6e0573089426
Reviewed-on: https://skia-review.googlesource.com/144348
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>

1 files changed, 19 insertions, 2 deletions

diff --git a/src/sksl/ir/SkSLAppendStage.h b/src/sksl/ir/SkSLAppendStage.h
index 87a8210a83..268ae979d2 100644
--- a/src/sksl/ir/SkSLAppendStage.h
+++ b/src/sksl/ir/SkSLAppendStage.h
@@ -23,7 +23,16 @@ struct AppendStage : public Expression {
     , fStage(stage)
     , fArguments(std::move(arguments)) {}
 
-    String description() const {
+    std::unique_ptr<Expression> clone() const override {
+        std::vector<std::unique_ptr<Expression>> cloned;
+        for (const auto& arg : fArguments) {
+            cloned.push_back(arg->clone());
+        }
+        return std::unique_ptr<Expression>(new AppendStage(fOffset, fStage, std::move(cloned),
+                                                           &fType));
+    }
+
+    String description() const override {
         String result = "append(";
         const char* separator = "";
         for (const auto& a : fArguments) {
@@ -35,7 +44,7 @@ struct AppendStage : public Expression {
         return result;
     }
 
-    bool hasSideEffects() const {
+    bool hasSideEffects() const override {
         return true;
     }
 
@@ -44,6 +53,14 @@ struct AppendStage : public Expression {
     std::vector<std::unique_ptr<Expression>> fArguments;
 
     typedef Expression INHERITED;
+
+private:
+    AppendStage(int offset, SkRasterPipeline::StockStage stage,
+                std::vector<std::unique_ptr<Expression>> arguments, const Type* type)
+    : INHERITED(offset, kAppendStage_Kind, *type)
+    , fStage(stage)
+    , fArguments(std::move(arguments)) {}
+
 };
 
 } // namespace