[PATCH] D22744: CodeExtractor : Add ability to preserve profile data.

[David Li via llvm-commits]

davidxl added inline comments.

================
Comment at: lib/Transforms/Utils/CodeExtractor.cpp:693
@@ +692,3 @@
+  for (auto &Weight : ExitWeights) {
+    if (Weight.second.getFrequency() == 0) {
+      HasValidWeights = false;
----------------
This check does not look correct. It is possible for the frequency to be zero

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Comment at: lib/Transforms/Utils/CodeExtractor.cpp:805
@@ +804,3 @@
+  // Update the entry count of the function.
+  if (BFI && EntryFreq.getFrequency() > 0) {
+    Optional<uint64_t> OptEntryCount =
----------------
The Freq > 0 check can be removed. I don't see how it can be zero (it is not actual count).

================
Comment at: lib/Transforms/Utils/CodeExtractor.cpp:808
@@ +807,3 @@
+        BFI->getProfileCountFromFreq(EntryFreq.getFrequency());
+    newFunction->setEntryCount( OptEntryCount.getValue());
+    BFI->setBlockFreq(codeReplacer, EntryFreq.getFrequency());
----------------
silvas wrote:
> nit: no space after the open paren
The check should be here: if optEntryCount has value (hasValue() returns true, not >0), set it to the newFunction entry.    hasValue is false when PGO is not enabled.




https://reviews.llvm.org/D22744