From: Duncan P. N. Exon Smith Date: Tue, 11 Mar 2014 18:18:12 +0000 (+0000) Subject: PGO: Clarify the testing README X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=fade78f1fdf70a91d2d0e580ec12d6d2d030b97e;p=clang PGO: Clarify the testing README git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@203593 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/test/Profile/README b/test/Profile/README index 8cf13c062f..3b66765711 100644 --- a/test/Profile/README +++ b/test/Profile/README @@ -1,8 +1,16 @@ -These are tests for instrumentation based profiling. This specifically -means the -fprofile-instr-generate and -fprofile-instr-use driver flags. - -Tests in this directory should test both the generation of profile -data, and the use of that same data. As such, the input source file -should include a main function such that building with -use and -running the resulting program would generate the input data that is -consumed in the -generate case. +These are tests for instrumentation based profiling. This specifically means +the -fprofile-instr-generate and -fprofile-instr-use driver flags. + +Tests in this directory should usually test both: + + - the generation of instrumentation (-fprofile-instr-generate), and + - the use of profile data from instrumented runs (-fprofile-instr-use). + +In order to test -fprofile-instr-use without actually running an instrumented +program, .profdata files are checked into Inputs/. + +The input source files must include a main function such that building with +-fprofile-instr-generate and running the resulting program generates the same +.profdata file that is consumed by the tests for -fprofile-instr-use. Even +tests that only check -fprofile-instr-use should include such a main function, +so that profile data can be regenerated as the .profdata file format evolves.