Add methods to merge an AttrBuilder into another builder.

This is useful when parsing an object that references multiple attribute groups.

N.B. If both builders have alignments specified, then they should match!

llvm-svn: 174480

1 files changed, 17 insertions, 0 deletions

diff --git a/llvm/lib/IR/Attributes.cpp b/llvm/lib/IR/Attributes.cpp
index dc1a6573439..67ab4eaa699 100644
--- a/llvm/lib/IR/Attributes.cpp
+++ b/llvm/lib/IR/Attributes.cpp
@@ -956,6 +956,23 @@ AttrBuilder &AttrBuilder::addStackAlignmentAttr(unsigned Align) {
   return *this;
 }
 
+AttrBuilder &AttrBuilder::merge(const AttrBuilder &B) {
+  // FIXME: What if both have alignments, but they don't match?!
+  if (!Alignment)
+    Alignment = B.Alignment;
+
+  if (!StackAlignment)
+    StackAlignment = B.StackAlignment;
+
+  Attrs.insert(B.Attrs.begin(), B.Attrs.end());
+
+  for (td_const_iterator I = B.TargetDepAttrs.begin(),
+         E = B.TargetDepAttrs.end(); I != E; ++I)
+    TargetDepAttrs[I->first] = I->second;
+
+  return *this;
+}
+
 bool AttrBuilder::contains(Attribute::AttrKind A) const {
   return Attrs.count(A);
 }