[llvm] [NewPM][CodeGen][WIP] Add callback style CodeGen pass pipeline builder (PR #104725)

[Matt Arsenault via llvm-commits]

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@@ -2221,3 +2338,578 @@ AAManager PassBuilder::buildDefaultAAPipeline() {
 
   return AA;
 }
+
+// Find the Profile remapping file name. The internal option takes the
+// precedence before getting from TargetMachine.
+static std::string getFSRemappingFile(const TargetMachine *TM,
+                                      const CGPassBuilderOption &Options) {
+  if (!Options.FSRemappingFile.empty())
+    return Options.FSRemappingFile;
+  const std::optional<PGOOptions> &PGOOpt = TM->getPGOOption();
+  if (PGOOpt == std::nullopt || PGOOpt->Action != PGOOptions::SampleUse)
+    return std::string();
+  return PGOOpt->ProfileRemappingFile;
+}
+
+// Find the FSProfile file name. The internal option takes the precedence
+// before getting from TargetMachine.
+static std::string getFSProfileFile(const TargetMachine *TM,
+                                    const CGPassBuilderOption &Options) {
+  if (!Options.FSProfileFile.empty())
+    return Options.FSProfileFile;
+  const std::optional<PGOOptions> &PGOOpt = TM->getPGOOption();
+  if (PGOOpt == std::nullopt || PGOOpt->Action != PGOOptions::SampleUse)
+    return std::string();
+  return PGOOpt->ProfileFile;
+}
+
+Error PassBuilder::addExceptionHandlingPasses(FunctionPassManager &FPM) {
+  const MCAsmInfo *MCAI = TM->getMCAsmInfo();
+  if (!MCAI)
+    return make_error<StringError>("No MCAsmInfo!", inconvertibleErrorCode());
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arsenm wrote:

Can this actually fail? I'd assume the target would be unimplemented 

https://github.com/llvm/llvm-project/pull/104725