Commit Graph

10 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
49b2803ec2 Prepare remaining tests for -join-physreg going away.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130893 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-04 23:54:59 +00:00
Andrew Trick
12f0dc6bb5 In the pre-RA scheduler, maintain cmp+br proximity.
This is done by pushing physical register definitions close to their
use, which happens to handle flag definitions if they're not glued to
the branch. This seems to be generally a good thing though, so I
didn't need to add a target hook yet.

The primary motivation is to generate code closer to what people
expect and rule out missed opportunity from enabling macro-op
fusion. As a side benefit, we get several 2-5% gains on x86
benchmarks. There is one regression:
SingleSource/Benchmarks/Shootout/lists slows down be -10%. But this is
an independent scheduler bug that will be tracked separately.
See rdar://problem/9283108.

Incidentally, pre-RA scheduling is only half the solution. Fixing the
later passes is tracked by:
<rdar://problem/8932804> [pre-RA-sched] on x86, attempt to schedule CMP/TEST adjacent with condition jump

Fixes:
<rdar://problem/9262453> Scheduler unnecessary break of cmp/jump fusion


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129508 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-14 05:15:06 +00:00
Jakob Stoklund Olesen
7eb589d3f9 Try again to disable critical edge splitting in CodeGenPrepare.
The bug that broke i386 linux has been fixed in r115191.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115204 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-30 20:51:52 +00:00
Jakob Stoklund Olesen
08342f2d11 Revert "Disable codegen prepare critical edge splitting. Machine instruction passes now"
This reverts revision 114633. It was breaking llvm-gcc-i386-linux-selfhost.

It seems there is a downstream bug that is exposed by
-cgp-critical-edge-splitting=0. When that bug is fixed, this patch can go back
in.

Note that the changes to tailcallfp2.ll are not reverted. They were good are
required.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114859 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-27 18:43:48 +00:00
Evan Cheng
dd3a41a6b3 Disable codegen prepare critical edge splitting. Machine instruction passes now
break critical edges on demand.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114633 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-23 06:55:34 +00:00
Jakob Stoklund Olesen
6ff1c3f36c Remove the SimpleJoin optimization from SimpleRegisterCoalescing.
Measurements show that it does not speed up coalescing, so there is no reason
the keep the added complexity around.

Also clean out some unused methods and static functions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106548 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-22 16:13:57 +00:00
Evan Cheng
9f68948609 Try trivial remat before the coalescer gives up on a vr / physreg coalescing for fear of tying up a physical register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99575 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-26 00:07:25 +00:00
Chris Lattner
47cdf4abff Make the NDEBUG assertion stronger and more clear what is
happening.

Enhance scheduling to set the DEAD flag on implicit defs
more aggressively.  Before, we'd set an implicit def operand
to dead if it were present in the SDNode corresponding to
the machineinstr but had no use.  Now we do it in this case
AND if the implicit def does not exist in the SDNode at all.

This exposes a couple of problems: one is the FIXME, which
causes a live intervals crash on CodeGen/X86/sibcall.ll.
The second is that it makes machinecse and licm more 
aggressive (which is a good thing) but also exposes a case
where licm hoists a set0 and then it doesn't get resunk.

Talking to codegen folks about both these issues, but I need
this patch in in the meantime.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99485 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25 05:40:48 +00:00
Dan Gohman
36a0947820 Eliminate more uses of llvm-as and llvm-dis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81290 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-08 23:54:48 +00:00
Dan Gohman
b24380804c PR2659 was fixed by r61847. Add the testcase as a regression test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61986 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-09 08:16:12 +00:00