jdk8-mips64-public/hotspot: ASSEMBLY

[C2] disjoint_byte_copy: fix unaligned LW/SW

/mnt/j2sdk-image/bin/java \
-XX:+PrintCompilation \
-XX:CompileCommand="compileonly,java/util/jar/Manifest\$FastInputStream.*" \
-jar SPECjvm2008.jar -ikv -coe -ict -bt 1 \
compress

It triggers 35000 unaligned instructions.

280 CALL_LEAF_NOFP,runtime jbyte_arraycopy

a0: (-122610748, .) fc127a6b pc: ffe9809004 <-- src是个奇地址
a1: (-122610748, .) fc128100 pc: ffe980910c <-- dest是个偶地址
a2: (-122610748, .) 2b pc: ffe9809210
t3: (-122610748, .) fc127a6c pc: ffe98093a4 <-- 试图把src对齐4字节，
t0: (-122610748, .) fc128101 pc: ffe98094a8 <-- 则dest就不对齐了，使用sw就出了unalign
t3: (-122610747, *) fc127a70 pc: ffe98093a4
t0: (-122610747, .) fc128105 pc: ffe98094a8 <-- 后面所有对dest的访问都会unalign
t3: (-122610746, *) fc127a74 pc: ffe98093a4
t0: (-122610746, .) fc128109 pc: ffe98094a8

Effect:
* 0 unaligned instructions.

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Mercurial > jdk8-mips64-public > hotspot / file revision

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