SkRasterPipeline::compile().

I'm not yet caching these in the blitter, and speed is essentially unchanged in the bench where I am now building and compiling the pipeline only once.  This may not be able to stay a simple std::function after I figure out caching, but for now it's a nice fit.

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=3911

Change-Id: I9545af589f73baf9f17cb4e6ace9a814c2478fe9
Reviewed-on: https://skia-review.googlesource.com/3911
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>

5 files changed, 14 insertions, 12 deletions

diff --git a/src/core/SkOpts.cpp b/src/core/SkOpts.cpp
index c082b160ee..6648909d1a 100644
--- a/src/core/SkOpts.cpp
+++ b/src/core/SkOpts.cpp
@@ -89,7 +89,7 @@ namespace SkOpts {
 
     DEFINE_DEFAULT(hash_fn);
 
-    DEFINE_DEFAULT(run_pipeline);
+    DEFINE_DEFAULT(compile_pipeline);
 #undef DEFINE_DEFAULT
 
     // Each Init_foo() is defined in src/opts/SkOpts_foo.cpp.
diff --git a/src/core/SkOpts.h b/src/core/SkOpts.h
index 7283030068..8e1b7fec8a 100644
--- a/src/core/SkOpts.h
+++ b/src/core/SkOpts.h
@@ -12,6 +12,7 @@
 #include "SkTextureCompressor.h"
 #include "SkTypes.h"
 #include "SkXfermode.h"
+#include <functional>
 
 struct ProcCoeff;
 
@@ -73,7 +74,8 @@ namespace SkOpts {
         return hash_fn(data, bytes, seed);
     }
 
-    extern void (*run_pipeline)(size_t, size_t, const SkRasterPipeline::Stage*, int);
+    extern
+    std::function<void(size_t, size_t)> (*compile_pipeline)(const SkRasterPipeline::Stage*, int);
 }
 
 #endif//SkOpts_DEFINED
diff --git a/src/core/SkRasterPipeline.cpp b/src/core/SkRasterPipeline.cpp
index 707a33ae6f..54de6793b0 100644
--- a/src/core/SkRasterPipeline.cpp
+++ b/src/core/SkRasterPipeline.cpp
@@ -22,6 +22,6 @@ void SkRasterPipeline::extend(const SkRasterPipeline& src) {
     }
 }
 
-void SkRasterPipeline::run(size_t x, size_t n) const {
-    SkOpts::run_pipeline(x,n, fStages, fNum);
+std::function<void(size_t, size_t)> SkRasterPipeline::compile() const {
+    return SkOpts::compile_pipeline(fStages, fNum);
 }
diff --git a/src/core/SkRasterPipeline.h b/src/core/SkRasterPipeline.h
index 60279dd168..548e503c84 100644
--- a/src/core/SkRasterPipeline.h
+++ b/src/core/SkRasterPipeline.h
@@ -11,6 +11,7 @@
 #include "SkNx.h"
 #include "SkTArray.h"
 #include "SkTypes.h"
+#include <functional>
 
 /**
  * SkRasterPipeline provides a cheap way to chain together a pixel processing pipeline.
@@ -85,11 +86,8 @@ public:
     // Append all stages to this pipeline.
     void extend(const SkRasterPipeline&);
 
-    // Run the pipeline constructed with append(), walking x through [x,x+n),
-    // generally in 4-pixel steps, with perhaps one jagged tail step.
-    void run(size_t x, size_t n) const;
-    void run(size_t n) const { this->run(0, n); }
-
+    // Runs the pipeline walking x through [x,x+n).
+    std::function<void(size_t x, size_t n)> compile() const;
 
     struct Stage {
         StockStage stage;
diff --git a/src/core/SkRasterPipelineBlitter.cpp b/src/core/SkRasterPipelineBlitter.cpp
index 91d60bee3a..ec634c8b98 100644
--- a/src/core/SkRasterPipelineBlitter.cpp
+++ b/src/core/SkRasterPipelineBlitter.cpp
@@ -149,6 +149,8 @@ void SkRasterPipelineBlitter::append_store(SkRasterPipeline* p, void* dst) const
     }
 }
 
+// TODO: Figure out how to cache some of the compiled pipelines.
+
 void SkRasterPipelineBlitter::blitH(int x, int y, int w) {
     auto dst = fDst.writable_addr(0,y);
 
@@ -159,7 +161,7 @@ void SkRasterPipelineBlitter::blitH(int x, int y, int w) {
     p.extend(fXfermode);
     this->append_store(&p, dst);
 
-    p.run(x, w);
+    p.compile()(x,w);
 }
 
 void SkRasterPipelineBlitter::blitAntiH(int x, int y, const SkAlpha aa[], const int16_t runs[]) {
@@ -176,7 +178,7 @@ void SkRasterPipelineBlitter::blitAntiH(int x, int y, const SkAlpha aa[], const
 
     for (int16_t run = *runs; run > 0; run = *runs) {
         coverage = *aa * (1/255.0f);
-        p.run(x, run);
+        p.compile()(x, run);
 
         x    += run;
         runs += run;
@@ -210,6 +212,6 @@ void SkRasterPipelineBlitter::blitMask(const SkMask& mask, const SkIRect& clip)
         }
         this->append_store(&p, dst);
 
-        p.run(x, clip.width());
+        p.compile()(x, clip.width());
     }
 }