Commit Graph

4 Commits

Author SHA1 Message Date
Richard Sandiford c3dc44781b [SystemZ] Make more use of TMHH
This originally came about after noticing that InstCombine turns
some of the TMHH (icmp (and...), ...) tests into plain comparisons.
Since there is no instruction to compare with a 64-bit immediate,
TMHH is generally better than an ordered comparison for the cases
that it can handle.

llvm-svn: 197238
2013-12-13 15:46:55 +00:00
Richard Sandiford f03789ca3f [SystemZ] Fix TMHH and TMHL usage for z10 with -O0
I've no idea why I decided to handle TMxx differently from all the other
high/low logic operations, but it was a stupid thing to do.  The high
registers aren't available as separate 32-bit registers on z10,
so subreg_h32 can't be used on a GR64 there.

I've normally been testing with z196 and with -O3 and so hadn't noticed
this until now.

llvm-svn: 195473
2013-11-22 17:28:28 +00:00
Richard Sandiford 030c165710 [SystemZ] Try to fold shifts into TMxx
E.g. "SRL %r2, 2; TMLL %r2, 1" => "TMLL %r2, 4".

llvm-svn: 190672
2013-09-13 09:09:50 +00:00
Richard Sandiford 35b9be298a [SystemZ] Add support for TMHH, TMHL, TMLH and TMLL
For now just handles simple comparisons of an ANDed value with zero.
The CC value provides enough information to do any comparison for a
2-bit mask, and some nonzero comparisons with more populated masks,
but that's all future work.

llvm-svn: 189469
2013-08-28 10:31:43 +00:00