search for: b6581a81

...would use 0x1000, 0x2000, 0x3000 so as long as you had no more than 3 trailing calls you can still encode the discriminator in a 2-byte ULEB128. --paulr -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20161027/b6581a81/attachment.html>

Motivation: Many optimizations duplicate code. E.g. loop unroller duplicates the loop body, GVN duplicates computation, etc. The duplicated code will share the same debug info with the original code. For SamplePGO, the debug info is used to present the profile. Code duplication will affect profile accuracy. Taking loop unrolling for example: #1 foo(); #2 for (i = 0; i < N; i++) { #3 bar();