On Tue, 11 Jun 2024 11:35:28 GMT, Shaojin Wen <d...@openjdk.org> wrote:
>> After PR https://github.com/openjdk/jdk/pull/16245, C2 optimizes stores into >> primitive arrays by combining values into larger stores. >> >> This PR rewrites the code of appendNull and append(boolean) methods so that >> these two methods can be optimized by C2. > > Shaojin Wen has updated the pull request incrementally with one additional > commit since the last revision: > > revert Ah, another issue is method inlining. It seems that in 1.2, the method is not inlined: ` 103 StoreB === 88 78 101 80 [[ 18 ]] @byte[int:>=0] (java/lang/Cloneable,java/io/Serializable):exact+any *, idx=5; Memory: @byte[int:>=0] (java/lang/Cloneable,java/io/Serializable):NotNull:exact+any *, idx=5; !jvms: StringUTF16::putChar @ bci:52 (line 72)` In the extra information I only see `StringUTF16::putChar @ bci:52 (line 72)`, so this method was not inlined. So of course there are only the 2 stores to be merged from `putChar`. Maybe you can do something about this with `@ForceInline`. In 2.2 I see there is more inlining: ` 865 StoreB === 656 839 863 45 [[ 885 ]] @byte[int:>=0] (java/lang/Cloneable,java/io/Serializable):exact+any *, idx=10; Memory: @byte[int:>=0] (java/lang/Cloneable,java/io/Serializable):NotNull:exact+any *, idx=10; !jvms: StringUTF16::putChar0 @ bci:19 (line 1587) StringUTF16::putCharsAt @ bci:34 (line 1572) AbstractStringBuilder::appendNull @ bci:63 (line 647) AbstractStringBuilder::append @ bci:5 (line 587) StringBuilder::append @ bci:2 (line 179)` Though I cannot seem to map it to your java code, maybe you pasted things together wrongly here. ------------- PR Comment: https://git.openjdk.org/jdk/pull/19626#issuecomment-2162118831
