-
Enhancement
-
Resolution: Fixed
-
P4
-
17, 21, 22, 23
-
b08
We noticed in JDK-8323497 that `movptr` optimization done in JDK-8319406 is not covering the case of immediates that fit in 32-bit unsigned, but do not fit in 32-bit signed. In that case, we can maybe do `mov r32, imm32` and rely on x86 zero-extending 32->64 bit for us. Since `movl` encoding is smaller than sign-extending `movq`, we also save more code on most paths that JDK-8319406 improved.
This saves additional 0.1..0.8% of code for Xcomp HelloWorld.
https://github.com/openjdk/jdk/pull/17343
This saves additional 0.1..0.8% of code for Xcomp HelloWorld.
https://github.com/openjdk/jdk/pull/17343
- relates to
-
JDK-8323497 On x64, use 32-bit immediate moves for narrow klass base if possible
- In Progress
-
JDK-8319406 x86: Shorter movptr(reg, imm) for 32-bit immediates
- Resolved