commit 62ad2128255877ed41c714366861eee9c1da30dd
author Dávid Bolvanský <david.bolvansky@gmail.com> Wed Nov 06 23:07:17 2019 +0100
committer Dávid Bolvanský <david.bolvansky@gmail.com> Wed Nov 06 23:08:07 2019 +0100
tree 53b0a915153ae008f96ddd703296de12be58c75a
parent 77a60f0df673074a2c9276498f95a9eaadeece56

[Analysis] Attribute deref/deref_or_null should not prevent tail call optimization

llvm/lib/CodeGen/Analysis.cpp

diff --git a/llvm/lib/CodeGen/Analysis.cpp b/llvm/lib/CodeGen/Analysis.cpp
index 023c236..4b738ca 100644
--- a/llvm/lib/CodeGen/Analysis.cpp
+++ b/llvm/lib/CodeGen/Analysis.cpp
@@ -567,12 +567,16 @@
   AttrBuilder CalleeAttrs(cast<CallInst>(I)->getAttributes(),
                           AttributeList::ReturnIndex);
 
-  // NoAlias and NonNull are completely benign as far as calling convention
+  // Following attributes are completely benign as far as calling convention
   // goes, they shouldn't affect whether the call is a tail call.
   CallerAttrs.removeAttribute(Attribute::NoAlias);
   CalleeAttrs.removeAttribute(Attribute::NoAlias);
   CallerAttrs.removeAttribute(Attribute::NonNull);
   CalleeAttrs.removeAttribute(Attribute::NonNull);
+  CallerAttrs.removeAttribute(Attribute::Dereferenceable);
+  CalleeAttrs.removeAttribute(Attribute::Dereferenceable);
+  CallerAttrs.removeAttribute(Attribute::DereferenceableOrNull);
+  CalleeAttrs.removeAttribute(Attribute::DereferenceableOrNull);
 
   if (CallerAttrs.contains(Attribute::ZExt)) {
     if (!CalleeAttrs.contains(Attribute::ZExt))