Set up cache in vulkan to reuse GrVkPrograms (aka VkPipelines)

src/gpu/GrStencil.cpp

Index: src/gpu/GrStencil.cpp
diff --git a/src/gpu/GrStencil.cpp b/src/gpu/GrStencil.cpp
index f37aa317ec37b20f9ff0f731278ab27dedc8bf66..79bce9940ba8b23c6712a356a117cb50af3d2a4c 100644
--- a/src/gpu/GrStencil.cpp
+++ b/src/gpu/GrStencil.cpp
@@ -9,6 +9,8 @@
 
 #include "GrStencil.h"
 
+#include "GrProcessor.h"
+
 ////////////////////////////////////////////////////////////////////////////////
 // Stencil Rules for Merging user stencil space into clip
 
@@ -393,3 +395,9 @@ bool GrStencilSettings::GetClipPasses(
     }
     return false;
 }
+
+void GrStencilSettings::genKey(GrProcessorKeyBuilder* b) const {
+    SkASSERT(sizeof(GrStencilSettings) <= 6 * sizeof(uint32_t));

[bsalomon, 2016/03/22 14:00:33]

How about

static const int kCount = sizeof(GrStencilSettings) / sizeof(uint32_t);
GR_STATIC_ASSERT(0 == sizeof(GrStencilSettings) % sizeof(uint32_t));

Also, is this guy tightly packed or does it memset itself to zero?

[egdaniel, 2016/03/22 20:06:14]

Done. He does do a memset to zero in ctor. In general he is tightly packed
except for 16 bits of packing in middle which is also manually set to 0 to make
sure it is all nicely initialized.

+    uint32_t* key = b->add32n(6);
+    memcpy(key, this, sizeof(GrStencilSettings));
+}