[PATCH] D121737: [PseudoProbe] Do not emit pseudo probes when module is not probed.

[Hongtao Yu via Phabricator via llvm-commits]

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There is a case when a function has pseudo probe intrinsics but the module it resides does not have the probe desc. This could happen when the current module is not built with `-fpseudo-probe-for-profiling` while a function in it calls some other function from a probed module. In thinLTO mode, the callee function could be imported and inlined into the current function.
While this is undefined behavior, I'm fixing the asm printer to not ICE.

Alternatively we can adjust the inliner to exclude all probe intrinsics in this case, but it doesn't seem that there's any existing support to similar cases (in CloneFunction.cpp). I could not find a good certralized place to emit a warning either.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D121737

Files:
  llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp


Index: llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
===================================================================
--- llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1167,12 +1167,14 @@
 }
 
 void AsmPrinter::emitPseudoProbe(const MachineInstr &MI) {
-  auto GUID = MI.getOperand(0).getImm();
-  auto Index = MI.getOperand(1).getImm();
-  auto Type = MI.getOperand(2).getImm();
-  auto Attr = MI.getOperand(3).getImm();
-  DILocation *DebugLoc = MI.getDebugLoc();
-  PP->emitPseudoProbe(GUID, Index, Type, Attr, DebugLoc);
+  if (PP) {
+    auto GUID = MI.getOperand(0).getImm();
+    auto Index = MI.getOperand(1).getImm();
+    auto Type = MI.getOperand(2).getImm();
+    auto Attr = MI.getOperand(3).getImm();
+    DILocation *DebugLoc = MI.getDebugLoc();
+    PP->emitPseudoProbe(GUID, Index, Type, Attr, DebugLoc);
+  }
 }
 
 void AsmPrinter::emitStackSizeSection(const MachineFunction &MF) {


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