Merging r213773:

Merging r213773:
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r213773 | jholewinski | 2014-07-23 13:40:45 -0400 (Wed, 23 Jul 2014) | 5 lines

[NVPTX] Make sure we do not generate MULWIDE ISD nodes when optimizations are disabled

With optimizations disabled, we disable the isel patterns for mul.wide; but we
were still generating MULWIDE ISD nodes.  Now, we only try to generate MULWIDE
ISD nodes in DAGCombine if the optimization level is not zero.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@214309 91177308-0d34-0410-b5e6-96231b3b80d8