commit 012fc4e9d9b66b3ffb7838b0e29dadbb4863ee69
author Nicolas Geoffray <ngeoffray@google.com> Fri Jan 08 15:58:19 2016 +0000
committer Nicolas Geoffray <ngeoffray@google.com> Fri Jan 08 17:14:17 2016 +0000
tree abba308e56a3d81e5c3fceebc95fb37a0ffe9c7c
parent 5ee288c9dd99614e3a238f5efceeec6456e3499d

Don't encode a DexRegisterMap if there is no live register.

Change-Id: I76a291e6a0ac37f0590d16c7f5b866115588bc55

compiler/optimizing/stack_map_stream.cc

diff --git a/compiler/optimizing/stack_map_stream.cc b/compiler/optimizing/stack_map_stream.cc
index c60a4ea..4784de1 100644
--- a/compiler/optimizing/stack_map_stream.cc
+++ b/compiler/optimizing/stack_map_stream.cc
@@ -270,7 +270,7 @@
       stack_map.SetStackMask(stack_map_encoding_, *entry.sp_mask);
     }
 
-    if (entry.num_dex_registers == 0) {
+    if (entry.num_dex_registers == 0 || (entry.live_dex_registers_mask->NumSetBits() == 0)) {
       // No dex map available.
       stack_map.SetDexRegisterMapOffset(stack_map_encoding_, StackMap::kNoDexRegisterMap);
     } else {

compiler/optimizing/stack_map_test.cc

diff --git a/compiler/optimizing/stack_map_test.cc b/compiler/optimizing/stack_map_test.cc
index 560502f..604787f 100644
--- a/compiler/optimizing/stack_map_test.cc
+++ b/compiler/optimizing/stack_map_test.cc
@@ -614,6 +614,10 @@
   stream.BeginStackMapEntry(0, 64, 0x3, &sp_mask, number_of_dex_registers, 0);
   stream.EndStackMapEntry();
 
+  number_of_dex_registers = 1;
+  stream.BeginStackMapEntry(1, 67, 0x4, &sp_mask, number_of_dex_registers, 0);
+  stream.EndStackMapEntry();
+
   size_t size = stream.PrepareForFillIn();
   void* memory = arena.Alloc(size, kArenaAllocMisc);
   MemoryRegion region(memory, size);
@@ -622,7 +626,7 @@
   CodeInfo code_info(region);
   StackMapEncoding encoding = code_info.ExtractEncoding();
   ASSERT_EQ(0u, encoding.NumberOfBytesForStackMask());
-  ASSERT_EQ(1u, code_info.GetNumberOfStackMaps());
+  ASSERT_EQ(2u, code_info.GetNumberOfStackMaps());
 
   uint32_t number_of_location_catalog_entries = code_info.GetNumberOfLocationCatalogEntries();
   ASSERT_EQ(0u, number_of_location_catalog_entries);
@@ -638,6 +642,16 @@
 
   ASSERT_FALSE(stack_map.HasDexRegisterMap(encoding));
   ASSERT_FALSE(stack_map.HasInlineInfo(encoding));
+
+  stack_map = code_info.GetStackMapAt(1, encoding);
+  ASSERT_TRUE(stack_map.Equals(code_info.GetStackMapForDexPc(1, encoding)));
+  ASSERT_TRUE(stack_map.Equals(code_info.GetStackMapForNativePcOffset(67, encoding)));
+  ASSERT_EQ(1u, stack_map.GetDexPc(encoding));
+  ASSERT_EQ(67u, stack_map.GetNativePcOffset(encoding));
+  ASSERT_EQ(0x4u, stack_map.GetRegisterMask(encoding));
+
+  ASSERT_FALSE(stack_map.HasDexRegisterMap(encoding));
+  ASSERT_FALSE(stack_map.HasInlineInfo(encoding));
 }
 
 TEST(StackMapTest, InlineTest) {