[clang] [PassBuilder] Add a mechanism for adding passbuilder callbacks for static builds (PR #70171)

[William Moses via cfe-commits]

https://github.com/wsmoses updated https://github.com/llvm/llvm-project/pull/70171

>From fca61de1d6cf5fe68cfb51bfe5ca73d5d3948ba5 Mon Sep 17 00:00:00 2001
From: "William S. Moses" <gh at wsmoses.com>
Date: Wed, 25 Oct 2023 02:10:32 -0500
Subject: [PATCH] [PassBuilder] Add a mechanism for adding passbuilder
 callbacks without an extension mechanism or dlopen of plugin

---
 clang/lib/CodeGen/BackendUtil.cpp      | 3 +++
 llvm/include/llvm/Passes/PassBuilder.h | 5 +++++
 llvm/lib/LTO/LTOBackend.cpp            | 3 +++
 llvm/lib/Passes/PassBuilder.cpp        | 3 +++
 llvm/tools/opt/NewPMDriver.cpp         | 3 +++
 5 files changed, 17 insertions(+)

diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 70accce456d3c07..8dbe4d942df278d 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -909,6 +909,9 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
 #define HANDLE_EXTENSION(Ext)                                                  \
   get##Ext##PluginInfo().RegisterPassBuilderCallbacks(PB);
 #include "llvm/Support/Extension.def"
+  for (auto PassCallback : ListRegisterPassBuilderCallbacks) {
+    PassCallback(PB);
+  }
 
   // Register the target library analysis directly and give it a customized
   // preset TLI.
diff --git a/llvm/include/llvm/Passes/PassBuilder.h b/llvm/include/llvm/Passes/PassBuilder.h
index 2c7ceda7998eda1..d018dd1e69166f0 100644
--- a/llvm/include/llvm/Passes/PassBuilder.h
+++ b/llvm/include/llvm/Passes/PassBuilder.h
@@ -739,6 +739,11 @@ bool parseAnalysisUtilityPasses(
 
   return false;
 }
+
+//! List of pass builder callbacks to be applied, in addition to those imported
+//! from plugins or LLVM extensions.
+extern SmallVector<std::function<void(PassBuilder &)>>
+    ListRegisterPassBuilderCallbacks;
 }
 
 #endif
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
index ccc4276e36dacf0..28aabf8bdebb4d6 100644
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -187,6 +187,9 @@ static void RegisterPassPlugins(ArrayRef<std::string> PassPlugins,
 #define HANDLE_EXTENSION(Ext)                                                  \
   get##Ext##PluginInfo().RegisterPassBuilderCallbacks(PB);
 #include "llvm/Support/Extension.def"
+  for (auto PassCallback : ListRegisterPassBuilderCallbacks) {
+    PassCallback(PB);
+  }
 
   // Load requested pass plugins and let them register pass builder callbacks
   for (auto &PluginFN : PassPlugins) {
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index fde759026e5d780..21a7ecb88e96418 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -2099,3 +2099,6 @@ void PassBuilder::registerParseTopLevelPipelineCallback(
         &C) {
   TopLevelPipelineParsingCallbacks.push_back(C);
 }
+
+llvm::SmallVector<std::function<void(PassBuilder &)>>
+    ListRegisterPassBuilderCallbacks;
diff --git a/llvm/tools/opt/NewPMDriver.cpp b/llvm/tools/opt/NewPMDriver.cpp
index 6ae3f87099afd64..f072120d7461d4e 100644
--- a/llvm/tools/opt/NewPMDriver.cpp
+++ b/llvm/tools/opt/NewPMDriver.cpp
@@ -431,6 +431,9 @@ bool llvm::runPassPipeline(
 #define HANDLE_EXTENSION(Ext)                                                  \
   get##Ext##PluginInfo().RegisterPassBuilderCallbacks(PB);
 #include "llvm/Support/Extension.def"
+  for (auto PassCallback : ListRegisterPassBuilderCallbacks) {
+    PassCallback(PB);
+  }
 
   // Specially handle the alias analysis manager so that we can register
   // a custom pipeline of AA passes with it.