commit 10b57ca6900f9608b523b1a3c12d3cf1a3e6e158
author Wei Mi <wmi@google.com> Tue Apr 21 14:32:28 2020 -0700
committer Wei Mi <wmi@google.com> Mon Apr 27 08:34:15 2020 -0700
tree bebdbbf666f9e1ffb9b20234cef42217525b772e
parent 18e96a31fe0214eb435e131e6ff585a899694576

[ProfileSummary] Add partial profile annotation on IR.

Profile and profile summary are usually read only once and then annotated
on IR. The profile summary metadata on IR should include the value of the
newly added partial profile flag, so that compilation phase like thinlto
postlink can get the full set of profile information.

Differential Revision: https://reviews.llvm.org/D78310

llvm/lib/IR/ProfileSummary.cpp

diff --git a/llvm/lib/IR/ProfileSummary.cpp b/llvm/lib/IR/ProfileSummary.cpp
index 11d95ac..d6c3c50 100644
--- a/llvm/lib/IR/ProfileSummary.cpp
+++ b/llvm/lib/IR/ProfileSummary.cpp
@@ -65,18 +65,24 @@
 // "ProfileFormat" and a string representing the format ("InstrProf" or
 // "SampleProfile"). The rest of the elements of the outer MDTuple are specific
 // to the kind of profile summary as returned by getFormatSpecificMD.
-Metadata *ProfileSummary::getMD(LLVMContext &Context) {
+// IsPartialProfile is an optional field and \p AddPartialField will decide
+// whether to add a field for it.
+Metadata *ProfileSummary::getMD(LLVMContext &Context, bool AddPartialField) {
   const char *KindStr[3] = {"InstrProf", "CSInstrProf", "SampleProfile"};
-  Metadata *Components[] = {
-    getKeyValMD(Context, "ProfileFormat", KindStr[PSK]),
-    getKeyValMD(Context, "TotalCount", getTotalCount()),
-    getKeyValMD(Context, "MaxCount", getMaxCount()),
-    getKeyValMD(Context, "MaxInternalCount", getMaxInternalCount()),
-    getKeyValMD(Context, "MaxFunctionCount", getMaxFunctionCount()),
-    getKeyValMD(Context, "NumCounts", getNumCounts()),
-    getKeyValMD(Context, "NumFunctions", getNumFunctions()),
-    getDetailedSummaryMD(Context),
-  };
+  SmallVector<Metadata *, 16> Components;
+  Components.push_back(getKeyValMD(Context, "ProfileFormat", KindStr[PSK]));
+  Components.push_back(getKeyValMD(Context, "TotalCount", getTotalCount()));
+  Components.push_back(getKeyValMD(Context, "MaxCount", getMaxCount()));
+  Components.push_back(
+      getKeyValMD(Context, "MaxInternalCount", getMaxInternalCount()));
+  Components.push_back(
+      getKeyValMD(Context, "MaxFunctionCount", getMaxFunctionCount()));
+  Components.push_back(getKeyValMD(Context, "NumCounts", getNumCounts()));
+  Components.push_back(getKeyValMD(Context, "NumFunctions", getNumFunctions()));
+  if (AddPartialField)
+    Components.push_back(
+        getKeyValMD(Context, "IsPartialProfile", isPartialProfile()));
+  Components.push_back(getDetailedSummaryMD(Context));
   return MDTuple::get(Context, Components);
 }
 
@@ -141,10 +147,11 @@
 
 ProfileSummary *ProfileSummary::getFromMD(Metadata *MD) {
   MDTuple *Tuple = dyn_cast_or_null<MDTuple>(MD);
-  if (!Tuple || Tuple->getNumOperands() != 8)
+  if (!Tuple && (Tuple->getNumOperands() < 8 || Tuple->getNumOperands() > 9))
     return nullptr;
 
-  auto &FormatMD = Tuple->getOperand(0);
+  int i = 0;
+  auto &FormatMD = Tuple->getOperand(i++);
   ProfileSummary::Kind SummaryKind;
   if (isKeyValuePair(dyn_cast_or_null<MDTuple>(FormatMD), "ProfileFormat",
                      "SampleProfile"))
@@ -160,27 +167,41 @@
 
   uint64_t NumCounts, TotalCount, NumFunctions, MaxFunctionCount, MaxCount,
       MaxInternalCount;
-  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(1)), "TotalCount",
+  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(i++)), "TotalCount",
               TotalCount))
     return nullptr;
-  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(2)), "MaxCount", MaxCount))
+  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(i++)), "MaxCount", MaxCount))
     return nullptr;
-  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(3)), "MaxInternalCount",
+  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(i++)), "MaxInternalCount",
               MaxInternalCount))
     return nullptr;
-  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(4)), "MaxFunctionCount",
+  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(i++)), "MaxFunctionCount",
               MaxFunctionCount))
     return nullptr;
-  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(5)), "NumCounts", NumCounts))
+  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(i++)), "NumCounts",
+              NumCounts))
     return nullptr;
-  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(6)), "NumFunctions",
+  if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(i++)), "NumFunctions",
               NumFunctions))
     return nullptr;
+  // Initialize IsPartialProfile because the field is optional.
+  uint64_t IsPartialProfile = 0;
+
+  // IsPartialProfile is optional so it doesn't matter even if the next val
+  // is not IsPartialProfile.
+  if (getVal(dyn_cast<MDTuple>(Tuple->getOperand(i)), "IsPartialProfile",
+             IsPartialProfile)) {
+    // Need to make sure when IsPartialProfile is presented, we won't step
+    // over the bound of Tuple operand array.
+    if (Tuple->getNumOperands() < 9)
+      return nullptr;
+    i++;
+  }
 
   SummaryEntryVector Summary;
-  if (!getSummaryFromMD(dyn_cast<MDTuple>(Tuple->getOperand(7)), Summary))
+  if (!getSummaryFromMD(dyn_cast<MDTuple>(Tuple->getOperand(i++)), Summary))
     return nullptr;
   return new ProfileSummary(SummaryKind, std::move(Summary), TotalCount,
                             MaxCount, MaxInternalCount, MaxFunctionCount,
-                            NumCounts, NumFunctions);
+                            NumCounts, NumFunctions, IsPartialProfile);
 }