[PATCH] [X86] Make wide loads be managed by AtomicExpand

[JF Bastien]

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Comment at: test/CodeGen/X86/atomic-load-store-wide.ll:1
@@ -1,2 +1,2 @@
 ; RUN: llc < %s -mcpu=corei7 -march=x86 -verify-machineinstrs | FileCheck %s
 
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morisset wrote:
> jfb wrote:
> > Is there also a cmpxchg8b test for x86-64?
> I do not understand this point, 64 bits accesses are naturally atomic on x86-64 (provided some alignment constraints are respected).
> So there is no need for cmpxchg8b, and I do not know a case where they can be emitted by LLVM on x86-64.
Oh right! Ignore :)

http://reviews.llvm.org/D5404