Add 'nonnull', a new parameter and return attribute which indicates that the pointer is not null. Instcombine will elide comparisons between these and null. Patch by Luqman Aden!

llvm-svn: 209185

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/lib/IR/Function.cpp b/llvm/lib/IR/Function.cpp
index de8e66f1bca..fe32c4613e7 100644
--- a/llvm/lib/IR/Function.cpp
+++ b/llvm/lib/IR/Function.cpp
@@ -76,6 +76,14 @@ unsigned Argument::getArgNo() const {
   return ArgIdx;
 }
 
+/// hasNonNullAttr - Return true if this argument has the nonnull attribute on
+/// it in its containing function.
+bool Argument::hasNonNullAttr() const {
+  if (!getType()->isPointerTy()) return false;
+  return getParent()->getAttributes().
+    hasAttribute(getArgNo()+1, Attribute::NonNull);
+}
+
 /// hasByValAttr - Return true if this argument has the byval attribute on it
 /// in its containing function.
 bool Argument::hasByValAttr() const {