Revert "[MemProf] Memprof profile matching and annotation"

This reverts commit a212d8da94d08e229aa8d65283e4b116310bba10, and follow
on fixes 0cd6763fa93159b84d70a5bb602c24996acaafaa,
e9ff53d42feac7fc157718523275619a8106f2f3, and
37c6a25e9ab230e5e21fa34e246d9fec55275df0.

After re-reading the documentation for hash_combine, I don't think this
is the appropriate hash function to use for computing the hash to use as
a stack id in the metadata, since it is not guaranteed to produce stable
values across executions. I have not hit this problem, but plan to
switch to using an MD5 hash. I am hitting an issue with one of the bots
(https://lab.llvm.org/buildbot/#/builders/171/builds/20732)
where the values produced are only the lower 32 bits of the expected
hash values, however, which I assume is related to the implementation of
hash_combine and hash_code.

I believe I fixed all of the other bot failures with the follow on fixes,
which I'll merge into the new version before reapplying.

1 files changed, 1 insertions, 4 deletions

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 656e595..9f92410 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1306,10 +1306,7 @@ static void setPGOUseInstrumentor(CodeGenOptions &Opts,
   }
   std::unique_ptr<llvm::IndexedInstrProfReader> PGOReader =
     std::move(ReaderOrErr.get());
-  // Currently memprof profiles are only added at the IR level. Mark the profile
-  // type as IR in that case as well and the subsequent matching needs to detect
-  // which is available (might be one or both).
-  if (PGOReader->isIRLevelProfile() || PGOReader->hasMemoryProfile()) {
+  if (PGOReader->isIRLevelProfile()) {
     if (PGOReader->hasCSIRLevelProfile())
       Opts.setProfileUse(CodeGenOptions::ProfileCSIRInstr);
     else