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/utf.cc b/runtime/utf.cc
index a2d6363..5e9fdf7 100644
--- a/runtime/utf.cc
+++ b/runtime/utf.cc
@@ -178,6 +178,23 @@
return static_cast<int32_t>(hash);
}
+int32_t ComputeUtf16HashFromModifiedUtf8(const char* utf8, size_t utf16_length) {
+ uint32_t hash = 0;
+ while (utf16_length != 0u) {
+ const uint32_t pair = GetUtf16FromUtf8(&utf8);
+ const uint16_t first = GetLeadingUtf16Char(pair);
+ hash = hash * 31 + first;
+ --utf16_length;
+ const uint16_t second = GetTrailingUtf16Char(pair);
+ if (second != 0) {
+ hash = hash * 31 + second;
+ DCHECK_NE(utf16_length, 0u);
+ --utf16_length;
+ }
+ }
+ return static_cast<int32_t>(hash);
+}
+
uint32_t ComputeModifiedUtf8Hash(const char* chars) {
uint32_t hash = 0;
while (*chars != '\0') {