Merging r246990:

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r246990 | dsanders | 2015-09-08 10:07:03 +0100 (Tue, 08 Sep 2015) | 9 lines

[mips] Reserve address spaces 1-255 for software use.

Summary: And define them to have noop casts with address spaces 0-255.

Reviewers: pekka.jaaskelainen

Subscribers: pekka.jaaskelainen, llvm-commits

Differential Revision: http://reviews.llvm.org/D12678
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llvm-svn: 247538