The final result of all this refactoring: instead of doing stat immediately
followed by an open for every source file we open, probe the file system with
'open' and then do an fstat when it succeeds. open+fstat is faster than
stat+open because the kernel only has to perform the string->inode mapping
once. Presumably it gets faster the deeper in your filesystem a lookup
happens.
For -Eonly on cocoa.h, this reduces system time from 0.042s to 0.039s on
my machine, a 7.7% speedup.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@120066 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed