[PATCH] Consider error-reporting calls cold in BPI

[Hal Finkel]

Hello,

BranchProbabilityInfo, which is used by the SDAG builder to assign branch weights, contains a number of well-known heuristics for statically predicting branch outcomes. One of these heuristics assigns low probabilities to paths post-dominated by cold calls (calls with the cold attribute). This patch enhances that heuristic to consider 'error reporting' calls to also be cold. An 'error reporting' call is a call to perror or a call to fprintf, fwrite, etc. where stderr is the stream.

This is one of the suggested heuristics from:
http://impact.crhc.illinois.edu/shared/papers/pact-98-branchpred.pdf

I don't see any significant test-suite changes.

Please review.

Thanks again,
Hal

-- 
Hal Finkel
Assistant Computational Scientist
Leadership Computing Facility
Argonne National Laboratory
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