[PATCH] D97735: [Globals] Treat nobuiltin fns as maybe-derefined.

[Florian Hahn via Phabricator via llvm-commits]

This revision was landed with ongoing or failed builds.
This revision was automatically updated to reflect the committed changes.
Closed by commit rG5913d7705618: [Globals] Treat nobuiltin fns as maybe-derefined. (authored by fhahn).

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D97735/new/

https://reviews.llvm.org/D97735

Files:
  llvm/include/llvm/IR/GlobalValue.h
  llvm/lib/IR/Globals.cpp
  llvm/test/Transforms/DeadArgElim/pr49022-builtin-nobuiltin.ll


Index: llvm/test/Transforms/DeadArgElim/pr49022-builtin-nobuiltin.ll
===================================================================
--- llvm/test/Transforms/DeadArgElim/pr49022-builtin-nobuiltin.ll
+++ llvm/test/Transforms/DeadArgElim/pr49022-builtin-nobuiltin.ll
@@ -13,7 +13,7 @@
 define dso_local i32 @test_fn(ptr %ptr) {
 ; CHECK-LABEL: @test_fn(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    call void @_ZdlPv(ptr poison) #[[ATTR1:[0-9]+]]
+; CHECK-NEXT:    call void @_ZdlPv(ptr [[PTR:%.*]]) #[[ATTR1:[0-9]+]]
 ; CHECK-NEXT:    ret i32 1
 ;
 entry:
Index: llvm/lib/IR/Globals.cpp
===================================================================
--- llvm/lib/IR/Globals.cpp
+++ llvm/lib/IR/Globals.cpp
@@ -261,6 +261,13 @@
   setGlobalObjectFlag(HasSectionHashEntryBit, !S.empty());
 }
 
+bool GlobalValue::isNobuiltinFnDef() const {
+  const Function *F = dyn_cast<Function>(this);
+  if (!F || F->empty())
+    return false;
+  return F->hasFnAttribute(Attribute::NoBuiltin);
+}
+
 bool GlobalValue::isDeclaration() const {
   // Globals are definitions if they have an initializer.
   if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(this))
Index: llvm/include/llvm/IR/GlobalValue.h
===================================================================
--- llvm/include/llvm/IR/GlobalValue.h
+++ llvm/include/llvm/IR/GlobalValue.h
@@ -145,12 +145,20 @@
     case AppendingLinkage:
     case InternalLinkage:
     case PrivateLinkage:
-      return isInterposable();
+      // Optimizations may assume builtin semantics for functions defined as
+      // nobuiltin due to attributes at call-sites. To avoid applying IPO based
+      // on nobuiltin semantics, treat such function definitions as maybe
+      // derefined.
+      return isInterposable() || isNobuiltinFnDef();
     }
 
     llvm_unreachable("Fully covered switch above!");
   }
 
+  /// Returns true if the global is a function definition with the nobuiltin
+  /// attribute.
+  bool isNobuiltinFnDef() const;
+
 protected:
   /// The intrinsic ID for this subclass (which must be a Function).
   ///


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D97735.454804.patch
Type: text/x-patch
Size: 2082 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20220823/2d0d239e/attachment.bin>