Merging r258221:

Merging r258221:
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r258221 | qcolombet | 2016-01-19 15:29:03 -0800 (Tue, 19 Jan 2016) | 8 lines

[X86] Do not run shrink-wrapping on function with split-stack attribute or HiPE
calling convention.
The implementation of the related callbacks in the x86 backend for such
functions are not ready to deal with a prologue block that is not the entry
block of the function.

This fixes PR26107, but the longer term solution would be to fix those callbacks.

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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_38@258269 91177308-0d34-0410-b5e6-96231b3b80d8