Commit Graph

6 Commits

Author SHA1 Message Date
Ulrich Weigand 2eb027d21f [SystemZ] Implement conditional returns
Return is now considered a predicable instruction, and is converted
to a newly-added CondReturn (which maps to BCR to %r14) instruction by
the if conversion pass.

Also, fused compare-and-branch transform knows about conditional
returns, emitting the proper fused instructions for them.

This transform triggers on a *lot* of tests, hence the huge diffstat.
The changes are mostly jX to br %r14 -> bXr %r14.

Author: koriakin

Differential Revision: http://reviews.llvm.org/D17339

llvm-svn: 265689
2016-04-07 16:11:44 +00:00
Ulrich Weigand 1f6666a49c [SystemZ] Provide basic TargetTransformInfo implementation
This hooks up the TargetTransformInfo machinery for SystemZ,
and provides an implementation of getIntImmCost.

In addition, the patch adds the isLegalICmpImmediate and
isLegalAddImmediate TargetLowering overrides, and updates
a couple of test cases where we now generate slightly
better code.

llvm-svn: 233688
2015-03-31 12:52:27 +00:00
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