| commit | b08cbbd737e3b900a287e619f52bf0f593b6b7e7 | [log] [tgz] |
|---|---|---|
| author | Chris Lattner <sabre@nondot.org> | Sat May 19 00:43:44 2007 +0000 |
| committer | Chris Lattner <sabre@nondot.org> | Sat May 19 00:43:44 2007 +0000 |
| tree | 16c848d19de5b43aaca85ab67b3c62da4510dc14 | |
| parent | bde968823a888b9401987872d94c56b72107c476 [diff] |
Disable the (A == (B-A)) -> 2*A == B xform when the sub has multiple uses (in
this case, the xform introduces an extra operation). This compiles
PowerPC/compare-duplicate.ll into:
_test:
subf r2, r3, r4
cmplw cr0, r2, r3
bne cr0, LBB1_2 ;F
instead of:
_test:
slwi r2, r3, 1
subf r3, r3, r4
cmplw cr0, r4, r2
bne cr0, LBB1_2 ;F
This is target independent of course.
llvm-svn: 37246