[llvm] c5b6371 - [GC][NFC] Make getGCStrategy by name available in IR

[Max Kazantsev via llvm-commits]

Author: Max Kazantsev
Date: 2021-08-02T14:26:04+07:00
New Revision: c5b63714b520a2b271809d5f1257e5b3737b12ac

URL: https://github.com/llvm/llvm-project/commit/c5b63714b520a2b271809d5f1257e5b3737b12ac
DIFF: https://github.com/llvm/llvm-project/commit/c5b63714b520a2b271809d5f1257e5b3737b12ac.diff

LOG: [GC][NFC] Make getGCStrategy by name available in IR

We might want to use info from GC strategy in middle end analysis.
The motivation for this is provided in D99135: we may want to ask
a GC if it's going to work with a given pointer (currently this code
makes naive check by the method name).

Differetial Revision: https://reviews.llvm.org/D100559
Reviewed By: reames

Added: 
    

Modified: 
    llvm/include/llvm/IR/GCStrategy.h
    llvm/lib/CodeGen/GCMetadata.cpp
    llvm/lib/IR/GCStrategy.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/IR/GCStrategy.h b/llvm/include/llvm/IR/GCStrategy.h
index a69958d596c67..4fa8e3a8dcf4f 100644
--- a/llvm/include/llvm/IR/GCStrategy.h
+++ b/llvm/include/llvm/IR/GCStrategy.h
@@ -131,6 +131,9 @@ class GCStrategy {
 /// GCMetadataPrinterRegistery as well.
 using GCRegistry = Registry<GCStrategy>;
 
+/// Lookup the GCStrategy object associated with the given gc name.
+std::unique_ptr<GCStrategy> getGCStrategy(const StringRef Name);
+
 } // end namespace llvm
 
 #endif // LLVM_IR_GCSTRATEGY_H

diff  --git a/llvm/lib/CodeGen/GCMetadata.cpp b/llvm/lib/CodeGen/GCMetadata.cpp
index 8fae798b31d9a..af5515cc6bfd4 100644
--- a/llvm/lib/CodeGen/GCMetadata.cpp
+++ b/llvm/lib/CodeGen/GCMetadata.cpp
@@ -145,24 +145,9 @@ GCStrategy *GCModuleInfo::getGCStrategy(const StringRef Name) {
   if (NMI != GCStrategyMap.end())
     return NMI->getValue();
 
-  for (auto& Entry : GCRegistry::entries()) {
-    if (Name == Entry.getName()) {
-      std::unique_ptr<GCStrategy> S = Entry.instantiate();
-      S->Name = std::string(Name);
-      GCStrategyMap[Name] = S.get();
-      GCStrategyList.push_back(std::move(S));
-      return GCStrategyList.back().get();
-    }
-  }
-
-  if (GCRegistry::begin() == GCRegistry::end()) {
-    // In normal operation, the registry should not be empty.  There should
-    // be the builtin GCs if nothing else.  The most likely scenario here is
-    // that we got here without running the initializers used by the Registry
-    // itself and it's registration mechanism.
-    const std::string error = ("unsupported GC: " + Name).str() +
-      " (did you remember to link and initialize the CodeGen library?)";
-    report_fatal_error(error);
-  } else
-    report_fatal_error(std::string("unsupported GC: ") + Name);
+  std::unique_ptr<GCStrategy> S = llvm::getGCStrategy(Name);
+  S->Name = std::string(Name);
+  GCStrategyMap[Name] = S.get();
+  GCStrategyList.push_back(std::move(S));
+  return GCStrategyList.back().get();
 }

diff  --git a/llvm/lib/IR/GCStrategy.cpp b/llvm/lib/IR/GCStrategy.cpp
index 25dad5bec9ef3..f3bc5b74f8fd3 100644
--- a/llvm/lib/IR/GCStrategy.cpp
+++ b/llvm/lib/IR/GCStrategy.cpp
@@ -18,3 +18,21 @@ using namespace llvm;
 LLVM_INSTANTIATE_REGISTRY(GCRegistry)
 
 GCStrategy::GCStrategy() = default;
+
+std::unique_ptr<GCStrategy> llvm::getGCStrategy(const StringRef Name) {
+  for (auto &S : GCRegistry::entries())
+    if (S.getName() == Name)
+      return S.instantiate();
+
+  if (GCRegistry::begin() == GCRegistry::end()) {
+    // In normal operation, the registry should not be empty.  There should
+    // be the builtin GCs if nothing else.  The most likely scenario here is
+    // that we got here without running the initializers used by the Registry
+    // itself and it's registration mechanism.
+    const std::string error =
+        std::string("unsupported GC: ") + Name.str() +
+        " (did you remember to link and initialize the library?)";
+    report_fatal_error(error);
+  } else
+    report_fatal_error(std::string("unsupported GC: ") + Name.str());
+}