Commit Graph

10 Commits

Author SHA1 Message Date
Andrew Trick
f6c39412dd Revert r128175.
I'm backing this out for the second time. It was supposed to be fixed by r128164, but the mingw self-host must be defeating the fix.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128181 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-23 23:11:02 +00:00
Andrew Trick
d8fa01fbd7 Reapply Eli's r127852 now that the pre-RA scheduler can spill EFLAGS.
(target-specific branchless method for double-width relational comparisons on x86)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128175 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-23 22:16:02 +00:00
Eli Friedman
b6192d2a9f Revert r127852; it's apparently causing an ICE on mingw.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127909 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-18 21:12:29 +00:00
Eli Friedman
b4b8b0cc90 Add a target-specific branchless method for double-width relational
comparisons on x86.  Essentially, the way this works is that SUB+SBB sets
the relevant flags the same way a double-width CMP would.

This is a substantial improvement over the generic lowering in LLVM. The output
is also shorter than the gcc-generated output; I haven't done any detailed
benchmarking, though.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127852 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-18 02:34:11 +00:00
Cameron Zwarich
899eaa3569 Roll r127459 back in:
Optimize trivial branches in CodeGenPrepare, which often get created from the
lowering of objectsize intrinsics. Unfortunately, a number of tests were relying
on llc not optimizing trivial branches, so I had to add an option to allow them
to continue to test what they originally tested.

This fixes <rdar://problem/8785296> and <rdar://problem/9112893>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127498 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11 21:52:04 +00:00
Daniel Dunbar
950d3db5f4 Revert r127459, "Optimize trivial branches in CodeGenPrepare, which often get
created from the", it broke some GCC test suite tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127477 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11 19:30:30 +00:00
Cameron Zwarich
592ca3fda9 Optimize trivial branches in CodeGenPrepare, which often get created from the
lowering of objectsize intrinsics. Unfortunately, a number of tests were relying
on llc not optimizing trivial branches, so I had to add an option to allow them
to continue to test what they originally tested.

This fixes <rdar://problem/8785296> and <rdar://problem/9112893>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127459 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11 04:54:27 +00:00
Evan Cheng
00a99a3584 Run codegen dce pass for all targets at all optimization levels. Previously it's
only run for x86 with fastisel. I've found it being very effective in
eliminating some obvious dead code as result of formal parameter lowering
especially when tail call optimization eliminated the need for some of the loads
from fixed frame objects. It also shrinks a number of the tests. A couple of
tests no longer make sense and are now eliminated.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95493 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-06 09:07:11 +00:00
Evan Cheng
5fef8bc1cb Fix a bug introduced by r94490 where it created a X86ISD::CMP whose output type is different from its inputs.
This fixes PR6146.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94731 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-28 01:57:22 +00:00
Evan Cheng
8c7ecaf524 Implement cond ? -1 : 0 with sbb.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94490 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-26 02:00:44 +00:00