Reapply "[PGO] Fix name encoding for ObjC-like functions"

Function names in ObjC can have spaces in them. This interacts poorly
with name compression, which uses spaces to separate PGO names. Fix the
issue by using a different separator and update a test.

I chose "\01" as the separator because 1) it's non-printable, 2) we
strip it from PGO names, and 3) it's the next natural choice once "\00"
is discarded (that one's overloaded).

This reverts the revert commit beaf3d18. What's changed?

- I fixed up the covmap-V2 binary format tests using a linux VM.
- I updated the expected counts in instrprof-comdat.h to account for
  the fact that there have been bugfixes to clang coverage.
- I added an assert to make sure we don't get bitten by this again.

Differential Revision: http://reviews.llvm.org/D18516

llvm-svn: 264641

1 files changed, 8 insertions, 2 deletions

diff --git a/llvm/lib/ProfileData/InstrProf.cpp b/llvm/lib/ProfileData/InstrProf.cpp
index 2446521a5bc..1be3df4699c 100644
--- a/llvm/lib/ProfileData/InstrProf.cpp
+++ b/llvm/lib/ProfileData/InstrProf.cpp
@@ -158,9 +158,15 @@ void InstrProfSymtab::create(const Module &M) {
 
 int collectPGOFuncNameStrings(const std::vector<std::string> &NameStrs,
                               bool doCompression, std::string &Result) {
+  assert(NameStrs.size() && "No name data to emit");
+
   uint8_t Header[16], *P = Header;
   std::string UncompressedNameStrings =
-      join(NameStrs.begin(), NameStrs.end(), StringRef(" "));
+      join(NameStrs.begin(), NameStrs.end(), getInstrProfNameSeparator());
+
+  assert(StringRef(UncompressedNameStrings)
+                 .count(getInstrProfNameSeparator()) == (NameStrs.size() - 1) &&
+         "PGO name is invalid (contains separator token)");
 
   unsigned EncLen = encodeULEB128(UncompressedNameStrings.length(), P);
   P += EncLen;
@@ -238,7 +244,7 @@ int readPGOFuncNameStrings(StringRef NameStrings, InstrProfSymtab &Symtab) {
     }
     // Now parse the name strings.
     SmallVector<StringRef, 0> Names;
-    NameStrings.split(Names, ' ');
+    NameStrings.split(Names, getInstrProfNameSeparator());
     for (StringRef &Name : Names)
       Symtab.addFuncName(Name);