[instrprof] Add an overload to accept raw_string_ostream.

[snehasish]

Summary

Add an overload for InstrProfWriter::write so that users can emit the
buffer to a string. Also use this new overload for existing unit test
usecases.

[snehasish]

Fix capitalization in comment.

[tejohnson]

The change looks fine to me but is this patch missing the referenced unit test changes?:

Also use this new overload for existing unit test usecases.

[snehasish]

In D153904#4454737, @tejohnson wrote:

The change looks fine to me but is this patch missing the referenced unit test changes?:

Also use this new overload for existing unit test usecases.

Sorry, my wording wasn't clear. By changing L658 in InstrProfWriter.cpp to use the new overload (in writeBuffer), all the unit tests now implicitly call the new overload.

[tejohnson]

LGTM but please change description per your explanation

[snehasish]

In D153904#4456588, @tejohnson wrote:

LGTM but please change description per your explanation

Hmm, I amended the commit message in my branch but after landing it I don't see it in git log. Let me try to fix up.

[snehasish]

In D153904#4456647, @snehasish wrote:

In D153904#4456588, @tejohnson wrote:

LGTM but please change description per your explanation

Hmm, I amended the commit message in my branch but after landing it I don't see it in git log. Let me try to fix up.

Fixing up now (after other commits have landed on top of this one) is too risky without a revert and restore. Let me know if you feel strongly about updating the message.

[tejohnson]

In D153904#4456676, @snehasish wrote:

In D153904#4456647, @snehasish wrote:

In D153904#4456588, @tejohnson wrote:

LGTM but please change description per your explanation

Hmm, I amended the commit message in my branch but after landing it I don't see it in git log. Let me try to fix up.

Fixing up now (after other commits have landed on top of this one) is too risky without a revert and restore. Let me know if you feel strongly about updating the message.

It's fine as is then, the explanation is here in the patch if anyone is curious.

llvm/include/llvm/ProfileData/InstrProfWriter.h

public:
 
   /// Merge existing function counts from the given writer.
   void mergeRecordsFromWriter(InstrProfWriter &&IPW,
                               function_ref<void(Error)> Warn);
 
   /// Write the profile to \c OS
   Error write(raw_fd_ostream &OS);
 
+  /// Write the profile to a string output stream \c OS
+  Error write(raw_string_ostream &OS);
+
   /// Write the profile in text format to \c OS
   Error writeText(raw_fd_ostream &OS);
 
   /// Write temporal profile trace data to the header in text format to \c OS
   void writeTextTemporalProfTraceData(raw_fd_ostream &OS,
                                       InstrProfSymtab &Symtab);
 
   Error validateRecord(const InstrProfRecord &Func);

llvm/lib/ProfileData/InstrProfWriter.cpp

 }
 
 Error InstrProfWriter::write(raw_fd_ostream &OS) {
   // Write the hash table.
   ProfOStream POS(OS);
   return writeImpl(POS);
 }
 
+Error InstrProfWriter::write(raw_string_ostream &OS) {
+  ProfOStream POS(OS);
+  return writeImpl(POS);
+}
+
 std::unique_ptr<MemoryBuffer> InstrProfWriter::writeBuffer() {
   std::string Data;
   raw_string_ostream OS(Data);
-  ProfOStream POS(OS);
   // Write the hash table.
-  if (Error E = writeImpl(POS))
+  if (Error E = write(OS))
     return nullptr;
   // Return this in an aligned memory buffer.
   return MemoryBuffer::getMemBufferCopy(Data);
 }
 
 static const char *ValueProfKindStr[] = {
 #define VALUE_PROF_KIND(Enumerator, Value, Descr) #Enumerator,
 #include "llvm/ProfileData/InstrProfData.inc"