[FIX] Avoid creating BFI when emitting remarks for dead functions

Dead function has its body stripped away, and can cause various
analyses to panic. Also it does not make sense to apply analyses on
such function.

Reviewed By: xazax.hun, MaskRay, wenlei, hoy

Differential Revision: https://reviews.llvm.org/D84715

diff --git a/llvm/lib/LTO/LTO.cpp b/llvm/lib/LTO/LTO.cpp
index 6e1e399..6230216 100644 (file)
--- a/llvm/lib/LTO/LTO.cpp
+++ b/llvm/lib/LTO/LTO.cpp
@@ -798,7 +798,7 @@ Error LTO::linkRegularLTO(RegularLTOState::AddedModule Mod,
   for (GlobalValue *GV : Mod.Keep) {
     if (LivenessFromIndex && !ThinLTO.CombinedIndex.isGUIDLive(GV->getGUID())) {
       if (Function *F = dyn_cast<Function>(GV)) {
-        OptimizationRemarkEmitter ORE(F);
+        OptimizationRemarkEmitter ORE(F, nullptr);
         ORE.emit(OptimizationRemark(DEBUG_TYPE, "deadfunction", F)
                  << ore::NV("Function", F)
                  << " not added to the combined module ");

diff --git a/llvm/test/LTO/Resolution/X86/dead-strip-fulllto.ll b/llvm/test/LTO/Resolution/X86/dead-strip-fulllto.ll
index 4365931..fb4fde7 100644 (file)
--- a/llvm/test/LTO/Resolution/X86/dead-strip-fulllto.ll
+++ b/llvm/test/LTO/Resolution/X86/dead-strip-fulllto.ll
@@ -1,7 +1,8 @@
 ; RUN: opt -module-summary -o %t %s
 ; RUN: opt -module-summary -o %t2 %S/Inputs/dead-strip-fulllto.ll
 
-; RUN: llvm-lto2 run --pass-remarks-output=%t4.yaml --pass-remarks-filter=. \
+; Adding '--pass-remarks-with-hotness' should not cause crash.
+; RUN: llvm-lto2 run --pass-remarks-output=%t4.yaml --pass-remarks-filter=. --pass-remarks-with-hotness \
 ; RUN:               %t -r %t,main,px -r %t,live1, -r %t,live2,p -r %t,dead2,p \
 ; RUN:               %t2 -r %t2,live1,p -r %t2,live2, -r %t2,dead1,p -r %t2,dead2, -r %t2,odr, \
 ; RUN:               -save-temps -o %t3