Add -fno-strict-aliasing to LinuxPPC builds #3087
Conversation
|
@gacholio FYI. @dnakamura would you kindly review? |
|
Hmmm. Found another place ( |
|
Maybe we should ignore this until cmake is live. UMA is a "maze of twisty little passages, all alike". This should also be applied to 390 and ARM, if they don't already have it. |
The compilers are being upgraded (if they haven't been already) and I'm concerned that waiting for cmake may leave us with a tail of odd bugs. My preference is to hit all the points we can, and even if some are missed, we've narrowed the bug window. |
pshipton
changed the title
|
@pdbain-ibm renamed the title to include WIP, please remove when you are ready to un-pause. |
| @@ -128,7 +128,7 @@ ifndef UMA_DO_NOT_OPTIMIZE_CCODE | |||
| <#elseif uma.spec.processor.arm> | |||
| UMA_OPTIMIZATION_CXXFLAGS += -g -O3 -fno-strict-aliasing $(ARM_ARCH_FLAGS) -Wno-unused-but-set-variable | |||
| <#elseif uma.spec.processor.ppc> | |||
| UMA_OPTIMIZATION_CXXFLAGS += -O3 | |||
| UMA_OPTIMIZATION_CXXFLAGS += -O3 -fno-strict-aliasing | |||
There was a problem hiding this comment.
Did you mean to also modify the UMA_OPTIMIZATION_CFLAGS above?
There was a problem hiding this comment.
Yes, testing that.
|
This appears to be adding the -f to xlC command lines. It should apply only to gcc. |
Update both UMA_OPTIMIZATION_CFLAGS and UMA_OPTIMIZATION_CXXFLAGS for GCC compilation. Signed-off-by: Peter Bain <[email protected]>
|
Added ifdefs to apply the comment only for GCC. Requested a performance run with the option added to the C flags also. |
|
It's also worth noting that these changes will have no effect on the JIT or OMR code. |
pdbain-ibm
changed the title
|
Performance team reports that this has no observable effect on performance. |
|
What have you done about OMR and JIT? |
|
I haven't made any changes there. |
|
I'll leave it up to @DanHeidinga and @pshipton to decide if the half-measure is worth committing. |
This is a glass half-full, glass half-empty kind of thing. I prefer to see this as a step on the path to get having the option used across the board and as such would be willing to commit it (post review / test of course!) |
|
fine with me, although I'd wait until after the 0.11.0 release |
|
jenkins test sanity plinux jdk8 |
|
jenkins compile aix jdk8 |
Applies to LinuxPPC only. This protects against possible functional errors
due to less-than-rigorous casting.
No effect on performance.
Signed-off-by: Peter Bain [email protected]