[llvm-exegesis][NFC] Improve parsing of the YAML files
[llvm-exegesis][NFC] Improve parsing of the YAML files

Summary: sscanf turns out to be slow for reading floating points.

Reviewers: courbet

Subscribers: tschuett, llvm-commits, RKSimon

Differential Revision: https://reviews.llvm.org/D52866

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@343771 91177308-0d34-0410-b5e6-96231b3b80d8

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