[clang] 1331728 - [NewPM] Use the default AA pipeline by default

[Arthur Eubanks via cfe-commits]

Author: Arthur Eubanks
Date: 2021-11-04T15:10:34-07:00
New Revision: 13317286f8298eb3bafa9ddebd1c03bef4918948

URL: https://github.com/llvm/llvm-project/commit/13317286f8298eb3bafa9ddebd1c03bef4918948
DIFF: https://github.com/llvm/llvm-project/commit/13317286f8298eb3bafa9ddebd1c03bef4918948.diff

LOG: [NewPM] Use the default AA pipeline by default

We almost always want to use the default AA pipeline. It's very easy for
users of PassBuilder to forget to customize the AAManager to use the
default AA pipeline (for example, the NewPM C API forgets to do this).

If somebody wants a custom AA pipeline, similar to what is being done
now with the default AA pipeline registration, they can

  FAM.registerPass([&] { return std::move(MyAA); });

before calling

  PB.registerFunctionAnalyses(FAM);

For example, LTOBackend.cpp and NewPMDriver.cpp do this.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D113210

Added: 
    

Modified: 
    clang/lib/CodeGen/BackendUtil.cpp
    llvm/lib/LTO/LTOBackend.cpp
    llvm/lib/LTO/ThinLTOCodeGenerator.cpp
    llvm/lib/Passes/PassBuilder.cpp
    llvm/tools/llvm-opt-fuzzer/llvm-opt-fuzzer.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index e7ed77bcb60f..2d467e8dea81 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1312,9 +1312,6 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
   get##Ext##PluginInfo().RegisterPassBuilderCallbacks(PB);
 #include "llvm/Support/Extension.def"
 
-  // Register the AA manager first so that our version is the one used.
-  FAM.registerPass([&] { return PB.buildDefaultAAPipeline(); });
-
   // Register the target library analysis directly and give it a customized
   // preset TLI.
   Triple TargetTriple(TheModule->getTargetTriple());

diff  --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
index d0e3b45d2bc1..be06556b0c3b 100644
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -251,18 +251,16 @@ static void runNewPMPasses(const Config &Conf, Module &Mod, TargetMachine *TM,
     TLII->disableAllFunctions();
   FAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
 
-  AAManager AA;
   // Parse a custom AA pipeline if asked to.
   if (!Conf.AAPipeline.empty()) {
+    AAManager AA;
     if (auto Err = PB.parseAAPipeline(AA, Conf.AAPipeline)) {
       report_fatal_error(Twine("unable to parse AA pipeline description '") +
                          Conf.AAPipeline + "': " + toString(std::move(Err)));
     }
-  } else {
-    AA = PB.buildDefaultAAPipeline();
+    // Register the AA manager first so that our version is the one used.
+    FAM.registerPass([&] { return std::move(AA); });
   }
-  // Register the AA manager first so that our version is the one used.
-  FAM.registerPass([&] { return std::move(AA); });
 
   // Register all the basic analyses with the managers.
   PB.registerModuleAnalyses(MAM);

diff  --git a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
index b4c1836c678d..9474d8c9dafb 100644
--- a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
+++ b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -291,11 +291,6 @@ static void optimizeModuleNewPM(Module &TheModule, TargetMachine &TM,
     TLII->disableAllFunctions();
   FAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
 
-  AAManager AA = PB.buildDefaultAAPipeline();
-
-  // Register the AA manager first so that our version is the one used.
-  FAM.registerPass([&] { return std::move(AA); });
-
   // Register all the basic analyses with the managers.
   PB.registerModuleAnalyses(MAM);
   PB.registerCGSCCAnalyses(CGAM);

diff  --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index baf150190026..74d96c732acd 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -413,6 +413,11 @@ void PassBuilder::registerCGSCCAnalyses(CGSCCAnalysisManager &CGAM) {
 }
 
 void PassBuilder::registerFunctionAnalyses(FunctionAnalysisManager &FAM) {
+  // We almost always want the default alias analysis pipeline.
+  // If a user wants a 
diff erent one, they can register their own before calling
+  // registerFunctionAnalyses().
+  FAM.registerPass([&] { return buildDefaultAAPipeline(); });
+
 #define FUNCTION_ANALYSIS(NAME, CREATE_PASS)                                   \
   FAM.registerPass([&] { return CREATE_PASS; });
 #include "PassRegistry.def"

diff  --git a/llvm/tools/llvm-opt-fuzzer/llvm-opt-fuzzer.cpp b/llvm/tools/llvm-opt-fuzzer/llvm-opt-fuzzer.cpp
index 7cf7b1feb3b7..265c8ac47fb6 100644
--- a/llvm/tools/llvm-opt-fuzzer/llvm-opt-fuzzer.cpp
+++ b/llvm/tools/llvm-opt-fuzzer/llvm-opt-fuzzer.cpp
@@ -144,7 +144,6 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
   ModulePassManager MPM;
   ModuleAnalysisManager MAM;
 
-  FAM.registerPass([&] { return PB.buildDefaultAAPipeline(); });
   PB.registerModuleAnalyses(MAM);
   PB.registerCGSCCAnalyses(CGAM);
   PB.registerFunctionAnalyses(FAM);