Merging r200775:

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r200775 | thomas.stellard | 2014-02-04 09:18:42 -0800 (Tue, 04 Feb 2014) | 5 lines

R600/SI: Don't assume copies will be coalesced in SIFixSGPRCopies

There is no lit test for this, because it would be too big and
complicated, but it does fix a crash in the Arithm/Absdiff.* OpenCV
test.

llvm-svn: 204644