[PATCH] [Power] Improve the expansion of atomic loads/stores

[hfinkel at anl.gov]

Thanks! Commit whenever you're ready.

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Comment at: test/CodeGen/PowerPC/atomics-indexed.ll:2
@@ +1,3 @@
+; RUN: llc < %s -mtriple=powerpc-apple-darwin -march=ppc32 -verify-machineinstrs | FileCheck %s --check-prefix=CHECK --check-prefix=PPC32
+; FIXME: -verify-machineinstrs currently fail on ppc64 (mismatched register/instruction).
+; This is already checked for in Atomics-64.ll
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If at some point you could look at fixing this, that would be great.

http://reviews.llvm.org/D5587