Optimizing: Improve const-string code generation.
For strings in the boot image, use either direct pointers
or pc-relative addresses. For other strings, use PC-relative
access to the dex cache arrays for AOT and direct address of
the string's dex cache slot for JIT.
For aosp_flounder-userdebug:
- 32-bit boot.oat: -692KiB (-0.9%)
- 64-bit boot.oat: -948KiB (-1.1%)
- 32-bit dalvik cache total: -900KiB (-0.9%)
- 64-bit dalvik cache total: -3672KiB (-1.5%)
(contains more files than the 32-bit dalvik cache)
For aosp_flounder-userdebug forced to compile PIC:
- 32-bit boot.oat: -380KiB (-0.5%)
- 64-bit boot.oat: -928KiB (-1.0%)
- 32-bit dalvik cache total: -468KiB (-0.4%)
- 64-bit dalvik cache total: -1928KiB (-0.8%)
(contains more files than the 32-bit dalvik cache)
Bug: 26884697
Change-Id: Iec7266ce67e6fedc107be78fab2e742a8dab2696
diff --git a/runtime/safe_map.h b/runtime/safe_map.h
index 0e5b503..49f80f3 100644
--- a/runtime/safe_map.h
+++ b/runtime/safe_map.h
@@ -19,6 +19,7 @@
#include <map>
#include <memory>
+#include <type_traits>
#include "base/allocator.h"
#include "base/logging.h"
@@ -124,6 +125,18 @@
return result.first;
}
+ template <typename CreateFn>
+ V GetOrCreate(const K& k, CreateFn create) {
+ static_assert(std::is_same<V, typename std::result_of<CreateFn()>::type>::value,
+ "Argument `create` should return a value of type V.");
+ auto lb = lower_bound(k);
+ if (lb != end() && !key_comp()(k, lb->first)) {
+ return lb->second;
+ }
+ auto it = PutBefore(lb, k, create());
+ return it->second;
+ }
+
bool Equals(const Self& rhs) const {
return map_ == rhs.map_;
}