commit 2d7210188805292e463be4bcf7a133b654d7e0ea
author Mathieu Chartier <mathieuc@google.com> Mon Nov 10 11:08:06 2014 -0800
committer Mathieu Chartier <mathieuc@google.com> Tue Nov 18 12:27:37 2014 -0800
tree 7705a3bf841ae44b2396728fa22ed0b5dcb44dbf
parent e0491682d101c69bf88c3c24a965312129cbfa38

Change 64 bit ArtMethod fields to be pointer sized

Changed the 64 bit entrypoint and gc map fields in ArtMethod to be
pointer sized. This saves a large amount of memory on 32 bit systems.
Reduces ArtMethod size by 16 bytes on 32 bit.

Total number of ArtMethod on low memory mako: 169957
Image size: 49203 methods -> 787248 image size reduction.
Zygote space size: 1070 methods -> 17120 size reduction.
App methods: ~120k -> 2 MB savings.

Savings per app on low memory mako: 125K+ per app
(less active apps -> more image methods per app).

Savings depend on how often the shared methods are on dirty pages vs
shared.

TODO in another CL, delete gc map field from ArtMethod since we
should be able to get it from the Oat method header.

Bug: 17643507

Change-Id: Ie9508f05907a9f693882d4d32a564460bf273ee8

(cherry picked from commit e832e64a7e82d7f72aedbd7d798fb929d458ee8f)

runtime/asm_support.h

diff --git a/runtime/asm_support.h b/runtime/asm_support.h
index 26df045..4b4c885 100644
--- a/runtime/asm_support.h
+++ b/runtime/asm_support.h
@@ -148,13 +148,21 @@
 ADD_TEST_EQ(MIRROR_ART_METHOD_DEX_CACHE_METHODS_OFFSET,
             art::mirror::ArtMethod::DexCacheResolvedMethodsOffset().Int32Value())
 
-#define MIRROR_ART_METHOD_PORTABLE_CODE_OFFSET     (32 + MIRROR_OBJECT_HEADER_SIZE)
-ADD_TEST_EQ(MIRROR_ART_METHOD_PORTABLE_CODE_OFFSET,
-            art::mirror::ArtMethod::EntryPointFromPortableCompiledCodeOffset().Int32Value())
+#define MIRROR_ART_METHOD_PORTABLE_CODE_OFFSET_32     (48 + MIRROR_OBJECT_HEADER_SIZE)
+ADD_TEST_EQ(MIRROR_ART_METHOD_PORTABLE_CODE_OFFSET_32,
+            art::mirror::ArtMethod::EntryPointFromPortableCompiledCodeOffset(4).Int32Value())
 
-#define MIRROR_ART_METHOD_QUICK_CODE_OFFSET        (40 + MIRROR_OBJECT_HEADER_SIZE)
-ADD_TEST_EQ(MIRROR_ART_METHOD_QUICK_CODE_OFFSET,
-            art::mirror::ArtMethod::EntryPointFromQuickCompiledCodeOffset().Int32Value())
+#define MIRROR_ART_METHOD_QUICK_CODE_OFFSET_32        (40 + MIRROR_OBJECT_HEADER_SIZE)
+ADD_TEST_EQ(MIRROR_ART_METHOD_QUICK_CODE_OFFSET_32,
+            art::mirror::ArtMethod::EntryPointFromQuickCompiledCodeOffset(4).Int32Value())
+
+#define MIRROR_ART_METHOD_PORTABLE_CODE_OFFSET_64     (64 + MIRROR_OBJECT_HEADER_SIZE)
+ADD_TEST_EQ(MIRROR_ART_METHOD_PORTABLE_CODE_OFFSET_64,
+            art::mirror::ArtMethod::EntryPointFromPortableCompiledCodeOffset(8).Int32Value())
+
+#define MIRROR_ART_METHOD_QUICK_CODE_OFFSET_64        (48 + MIRROR_OBJECT_HEADER_SIZE)
+ADD_TEST_EQ(MIRROR_ART_METHOD_QUICK_CODE_OFFSET_64,
+            art::mirror::ArtMethod::EntryPointFromQuickCompiledCodeOffset(8).Int32Value())
 
 #if defined(__cplusplus)
 }  // End of CheckAsmSupportOffsets.