commit 1ca718ec2de53fb5ef2a9211bfcc921311775c90
author Mathieu Chartier <mathieuc@google.com> Tue Oct 23 12:55:34 2018 -0700
committer Mathieu Chartier <mathieuc@google.com> Tue Oct 30 16:03:00 2018 +0000
tree f5ce8c3f4edd022765c343cc5a9df8ebd292f0ec
parent ce2a00daa92670a4fc01ef59fdbc3769a846f69c

Add PreResolved strings dex cache array

For app images, this dex cache may be prepopulated to speed up
application startup. This new dex cache array is created when
--resolve-startup-const-strings=true.

Test: test-art-host
Bug: 116059983
Bug: 118385560

Change-Id: I379dc15174281665d7f4ceb106f7fbf51f89b921

runtime/class_linker.cc

diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index e240167..9b45b48 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -1415,9 +1415,9 @@
   for (size_t offset_index = 0; offset_index < num_string_offsets; ++offset_index) {
     uint32_t base_offset = sro_base[offset_index].first;
 
-    if (HasDexCacheNativeRefTag(base_offset)) {
-      base_offset = ClearDexCacheNativeRefTag(base_offset);
-      DCHECK_ALIGNED(base_offset,  2);
+    if (HasDexCacheStringNativeRefTag(base_offset)) {
+      base_offset = ClearDexCacheNativeRefTags(base_offset);
+      DCHECK_ALIGNED(base_offset, 2);
 
       ObjPtr<mirror::DexCache> dex_cache =
           reinterpret_cast<mirror::DexCache*>(space->Begin() + base_offset);
@@ -1437,10 +1437,27 @@
         dex_cache->GetStrings()[string_index].store(
             mirror::StringDexCachePair(it->second, source.index));
       }
+    } else if (HasDexCachePreResolvedStringNativeRefTag(base_offset)) {
+      base_offset = ClearDexCacheNativeRefTags(base_offset);
+      DCHECK_ALIGNED(base_offset, 2);
 
+      ObjPtr<mirror::DexCache> dex_cache =
+          reinterpret_cast<mirror::DexCache*>(space->Begin() + base_offset);
+      uint32_t string_index = sro_base[offset_index].second;
+
+      ObjPtr<mirror::String> referred_string =
+          dex_cache->GetPreResolvedStrings()[string_index].Read();
+      DCHECK(referred_string != nullptr);
+
+      auto it = intern_remap.find(referred_string.Ptr());
+      if (it != intern_remap.end()) {
+        // Because we are not using a helper function we need to mark the GC card manually.
+        WriteBarrier::ForEveryFieldWrite(dex_cache);
+        dex_cache->GetPreResolvedStrings()[string_index] = GcRoot<mirror::String>(it->second);
+      }
     } else {
       uint32_t raw_member_offset = sro_base[offset_index].second;
-      DCHECK_ALIGNED(base_offset,  2);
+      DCHECK_ALIGNED(base_offset, 2);
       DCHECK_ALIGNED(raw_member_offset, 2);
 
       ObjPtr<mirror::Object> obj_ptr =