commit 896f8f7fe562f6e59119cb32531da9f0a5f13d18
author Nicolas Geoffray <ngeoffray@google.com> Mon Mar 30 15:44:25 2015 +0100
committer Nicolas Geoffray <ngeoffray@google.com> Tue Mar 31 15:32:48 2015 +0100
tree 9f2b61474702a655ab5e793bac44d89612cf1b80
parent 7411a69982c055692966c685636b6a226f10215e

Use variable encoding for StackMap.

dex_pc, native_pc_offset, dex_register_map_offset, inline_info_offset,
and register_mask can now be encoded in 1, 2, 3, or 4 bytes.

Change-Id: I15f93e8226ce374204d44c5a80a9fd89bda2687c

compiler/optimizing/stack_map_stream.h

diff --git a/compiler/optimizing/stack_map_stream.h b/compiler/optimizing/stack_map_stream.h
index b77e604..a73c8d7 100644
--- a/compiler/optimizing/stack_map_stream.h
+++ b/compiler/optimizing/stack_map_stream.h
@@ -68,6 +68,7 @@
         stack_mask_max_(-1),
         dex_pc_max_(0),
         native_pc_offset_max_(0),
+        register_mask_max_(0),
         number_of_stack_maps_with_inline_info_(0),
         dex_map_hash_to_stack_map_indices_(std::less<uint32_t>(), allocator->Adapter()) {}
 
@@ -128,6 +129,7 @@
 
     dex_pc_max_ = std::max(dex_pc_max_, dex_pc);
     native_pc_offset_max_ = std::max(native_pc_offset_max_, native_pc_offset);
+    register_mask_max_ = std::max(register_mask_max_, register_mask);
   }
 
   void AddInlineInfoEntry(uint32_t method_index) {
@@ -156,7 +158,8 @@
         ComputeInlineInfoSize(),
         ComputeDexRegisterMapsSize(),
         dex_pc_max_,
-        native_pc_offset_max_);
+        native_pc_offset_max_,
+        register_mask_max_);
   }
 
   // Compute the size of the Dex register location catalog of `entry`.
@@ -248,8 +251,11 @@
       ComputeInlineInfoStart(),
       inline_info_size);
 
-    code_info.SetEncoding(
-        inline_info_size, dex_register_map_size, dex_pc_max_, native_pc_offset_max_);
+    code_info.SetEncoding(inline_info_size,
+                          dex_register_map_size,
+                          dex_pc_max_,
+                          native_pc_offset_max_,
+                          register_mask_max_);
     code_info.SetNumberOfStackMaps(stack_maps_.Size());
     code_info.SetStackMaskSize(stack_mask_size);
     DCHECK_EQ(code_info.GetStackMapsSize(), ComputeStackMapsSize());
@@ -476,6 +482,7 @@
   int stack_mask_max_;
   uint32_t dex_pc_max_;
   uint32_t native_pc_offset_max_;
+  uint32_t register_mask_max_;
   size_t number_of_stack_maps_with_inline_info_;
 
   ArenaSafeMap<uint32_t, GrowableArray<uint32_t>> dex_map_hash_to_stack_map_indices_;

compiler/optimizing/stack_map_test.cc

diff --git a/compiler/optimizing/stack_map_test.cc b/compiler/optimizing/stack_map_test.cc
index b9bf016..8d160bc 100644
--- a/compiler/optimizing/stack_map_test.cc
+++ b/compiler/optimizing/stack_map_test.cc
@@ -401,9 +401,8 @@
   // ...the offset of the second Dex register map (relative to the
   // beginning of the Dex register maps region) is 255 (i.e.,
   // kNoDexRegisterMapSmallEncoding).
-  ASSERT_NE(StackMap::kNoDexRegisterMap, stack_map1.GetDexRegisterMapOffset(code_info));
-  ASSERT_EQ(StackMap::kNoDexRegisterMapSmallEncoding,
-            stack_map1.GetDexRegisterMapOffset(code_info));
+  ASSERT_NE(stack_map1.GetDexRegisterMapOffset(code_info), StackMap::kNoDexRegisterMap);
+  ASSERT_EQ(stack_map1.GetDexRegisterMapOffset(code_info), 0xFFu);
 }
 
 TEST(StackMapTest, TestShareDexRegisterMap) {