[PGO] Allow value profile writer interface to allocated target buffer

Raw profile writer needs to write all data of one kind in one continuous block,
so the buffer needs to be pre-allocated and passed to the writer method in
pieces for function profile data. The change adds the support for raw value data
writing.

llvm-svn: 254219

1 files changed, 13 insertions, 9 deletions

diff --git a/llvm/lib/ProfileData/InstrProf.cpp b/llvm/lib/ProfileData/InstrProf.cpp
index 54c37e30dba..3bbc8249c3d 100644
--- a/llvm/lib/ProfileData/InstrProf.cpp
+++ b/llvm/lib/ProfileData/InstrProf.cpp
@@ -170,10 +170,12 @@ void serializeValueProfRecordFrom(ValueProfRecord *This,
   }
 }
 
-ValueProfData *serializeValueProfDataFrom(ValueProfRecordClosure *Closure) {
+ValueProfData *serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
+                                          ValueProfData *DstData) {
   uint32_t TotalSize = getValueProfDataSize(Closure);
 
-  ValueProfData *VPD = Closure->AllocValueProfData(TotalSize);
+  ValueProfData *VPD =
+      DstData ? DstData : Closure->AllocValueProfData(TotalSize);
 
   VPD->TotalSize = TotalSize;
   VPD->NumValueKinds = Closure->GetNumValueKinds(Closure->Record);
@@ -259,7 +261,7 @@ ValueProfData::serializeFrom(const InstrProfRecord &Record) {
   InstrProfRecordClosure.Record = &Record;
 
   std::unique_ptr<ValueProfData> VPD(
-      serializeValueProfDataFrom(&InstrProfRecordClosure));
+      serializeValueProfDataFrom(&InstrProfRecordClosure, 0));
   return VPD;
 }
 
@@ -367,16 +369,18 @@ uint32_t getValueProfDataSizeRT(const ValueProfRuntimeRecord *Record) {
 }
 
 /* Return a ValueProfData instance that stores the data collected
-   from runtime. */
+ * from runtime. If \c DstData is provided by the caller, the value
+ * profile data will be store in *DstData and DstData is returned,
+ * otherwise the method will allocate space for the value data and
+ * return pointer to the newly allocated space.
+ */
 ValueProfData *
-serializeValueProfDataFromRT(const ValueProfRuntimeRecord *Record) {
+serializeValueProfDataFromRT(const ValueProfRuntimeRecord *Record,
+                             ValueProfData *DstData) {
   RTRecordClosure.Record = Record;
-  return serializeValueProfDataFrom(&RTRecordClosure);
+  return serializeValueProfDataFrom(&RTRecordClosure, DstData);
 }
 
-
-
-
 void ValueProfRecord::deserializeTo(InstrProfRecord &Record,
                                     InstrProfRecord::ValueMapType *VMap) {
   Record.reserveSites(Kind, NumValueSites);