The various scalar bit operations set SCC,
so one is erased or moved it needs to be recomputed.
Not sure why the existing tests don't fail on this.
llvm-svn: 312819
Previous change "Turn s_and_saveexec_b64 into s_and_b64 if
result is unused" introduced asan use-after-poison error.
Instruction was analyzed after eraseFromParent() calls.
Move analysys higher than erase.
llvm-svn: 309779
With SI_END_CF elimination for some nested control flow we can now
eliminate saved exec register completely by turning a saveexec version
of instruction into just a logical instruction.
Differential Revision: https://reviews.llvm.org/D36007
llvm-svn: 309766
Add a pass to remove redundant S_OR_B64 instructions enabling lanes in
the exec. If two SI_END_CF (lowered as S_OR_B64) come together without any
vector instructions between them we can only keep outer SI_END_CF, given
that CFG is structured and exec bits of the outer end statement are always
not less than exec bit of the inner one.
This needs to be done before the RA to eliminate saved exec bits registers
but after register coalescer to have no vector registers copies in between
of different end cf statements.
Differential Revision: https://reviews.llvm.org/D35967
llvm-svn: 309762