Commit Graph

5 Commits

Author SHA1 Message Date
Michael Kuperstein 3e3652aef2 Recommit r274692 - [X86] Transform setcc + movzbl into xorl + setcc
xorl + setcc is generally the preferred sequence due to the partial register
stall setcc + movzbl suffers from. As a bonus, it also encodes one byte smaller.
This fixes PR28146.

The original commit tried inserting an 8bit-subreg into a GR32 (not GR32_ABCD)
which was not appreciated by fast regalloc on 32-bit.

llvm-svn: 274802
2016-07-07 22:50:23 +00:00
Michael Kuperstein edb38a94f8 Revert r274692 to check whether this is what breaks windows selfhost.
llvm-svn: 274771
2016-07-07 16:55:35 +00:00
Michael Kuperstein 1ef6c59b1d [X86] Transform setcc + movzbl into xorl + setcc
xorl + setcc is generally the preferred sequence due to the partial register
stall setcc + movzbl suffers from. As a bonus, it also encodes one byte smaller.

This fixes PR28146.

Differential Revision: http://reviews.llvm.org/D21774

llvm-svn: 274692
2016-07-06 21:56:18 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +00:00
Tim Northover 51472bc600 X86: lower ATOMIC_CMP_SWAP_WITH_SUCCESS directly
Lowering this new node allows us to fold the almost universal
comparison for success before it's even formed. Instead we can create
a copy from EFLAGS and an X86ISD::SETCC operation since all "cmpxchg"
instructions set the zero-flag to the correct value.

rdar://problem/13201607

llvm-svn: 210923
2014-06-13 17:29:39 +00:00