Fixes PR8287: SD scheduling time. The fix is a failsafe that prevents catastrophic compilation time in the event of unreasonable LLVM IR. Code quality is a separate issue--someone upstream needs to do a better job of reducing to llvm.memcpy. If the situation can be reproduced with any supported frontend, then it will be a separate bug.
Fixes PR8287: SD scheduling time. The fix is a failsafe that prevents
catastrophic compilation time in the event of unreasonable LLVM
IR. Code quality is a separate issue--someone upstream needs to do a
better job of reducing to llvm.memcpy. If the situation can be reproduced with
any supported frontend, then it will be a separate bug.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@118904 91177308-0d34-0410-b5e6-96231b3b80d8

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