Use JITServer check to create a relocation record for interface calls on Power #7386
Conversation
|
I should mention that this routine adds relocation records for |
fjeremic
added
arch:power
comp:jitserver
There was a problem hiding this comment.
I should mention that this routine adds relocation records for TR_J2IVirtualThunkPointer as well. But only if comp->compileRelocatableCode() returns true. Do we need to augment this check to check for comp->isOutOfProcessCompilation() as well? I did not see any failures related to this, but I do see that in the Z codegen this relo record is always added unconditionally.
No, we shouldn't need to relocate thunk pointers, they should be valid client-side pointers at this point for non-AOT JITServer compilations.
It probably doesn't hurt to emit relocations on Z because when the client applies the reloc it will just overwrite the thunk address with the same value. The same is probably true on P, but we already found out that relocs aren't applied the same way on every platform so lets just leave it be until there's reason to do otherwise.
| @@ -719,7 +719,7 @@ uint8_t *TR::PPCInterfaceCallSnippet::emitSnippetBody() | |||
| { | |||
| int32_t *patchAddr = (int32_t *)getLowerInstruction()->getBinaryEncoding(); | |||
| intptrj_t addrValue = (intptrj_t)cursor; | |||
| if (!comp->compileRelocatableCode()) | |||
| if (!comp->compileRelocatableCode() && !comp->isOutOfProcessCompilation()) | |||
There was a problem hiding this comment.
Can you add a comment on the else path here that explains to the reader that the immediate fields of the instructions being patched need to be clear for AOT and JITServer because the relocation ORs the relocated address into the fields and therefore can't tolerate any unexpectedly set bits? It will save someone a lot of grief in the future if they ever have to visit this part of the code.
[skip ci] Signed-off-by: Dhruv Chopra <Dhruv.C.Chopra@ibm.com>
dchopra001
force-pushed
the
interfaceCalls
branch
from
a746af6 to
dbd29ed
Compare
[skip ci]
Signed-off-by: Dhruv Chopra Dhruv.C.Chopra@ibm.com