[PATCH] D114284: [llvm-profgen] Truncate the context with zero probe ID

[Lei Wang via Phabricator via llvm-commits]

wlei updated this revision to Diff 388637.
wlei added a comment.

Updating D114284 <https://reviews.llvm.org/D114284>: [llvm-profgen] Truncate the context with zero probe ID


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D114284/new/

https://reviews.llvm.org/D114284

Files:
  llvm/tools/llvm-profgen/ProfileGenerator.cpp


Index: llvm/tools/llvm-profgen/ProfileGenerator.cpp
===================================================================
--- llvm/tools/llvm-profgen/ProfileGenerator.cpp
+++ llvm/tools/llvm-profgen/ProfileGenerator.cpp
@@ -760,12 +760,12 @@
       FunctionProfile.addHeadSamples(Count);
       // Look up for the caller's function profile
       const auto *InlinerDesc = Binary->getInlinerDescForProbe(Probe);
-      if (InlinerDesc != nullptr) {
+      SampleContextFrames CalleeContextId =
+          FunctionProfile.getContext().getContextFrames();
+      if (InlinerDesc != nullptr && CalleeContextId.size() > 1) {
         // Since the context id will be compressed, we have to use callee's
         // context id to infer caller's context id to ensure they share the
         // same context prefix.
-        SampleContextFrames CalleeContextId =
-            FunctionProfile.getContext().getContextFrames();
         SampleContextFrameVector CallerContextId;
         SampleContextFrame &&CallerLeafFrameLoc =
             getCallerContext(CalleeContextId, CallerContextId);
@@ -825,6 +825,20 @@
   SampleContextFrameVector NewContextStack(ContextStack.begin(),
                                            ContextStack.end());
   Binary->getInlineContextForProbe(LeafProbe, NewContextStack, true);
+
+  int ZeroProbeIdx = -1;
+  for (uint32_t I = 0; I < NewContextStack.size() - 1; I++) {
+    auto &Callsite = NewContextStack[I];
+    // Ignore the context if the probe of the callsite is zero.
+    if (Callsite.Location.LineOffset == 0)
+      ZeroProbeIdx = I;
+  }
+  if (ZeroProbeIdx != -1) {
+    std::copy(NewContextStack.begin() + ZeroProbeIdx + 1, NewContextStack.end(),
+              NewContextStack.begin());
+    NewContextStack.resize(NewContextStack.size() - ZeroProbeIdx - 1);
+  }
+
   // For leaf inlined context with the top frame, we should strip off the top
   // frame's probe id, like:
   // Inlined stack: [foo:1, bar:2], the ContextId will be "foo:1 @ bar"


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D114284.388637.patch
Type: text/x-patch
Size: 1990 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20211119/b5f9a57c/attachment.bin>