Implement function prefix data as an IR feature.

Previous discussion:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-July/063909.html

Differential Revision: http://llvm-reviews.chandlerc.com/D1191

llvm-svn: 190773
diff --git a/llvm/test/CodeGen/X86/prefixdata.ll b/llvm/test/CodeGen/X86/prefixdata.ll
new file mode 100644
index 0000000..2ffa89d
--- /dev/null
+++ b/llvm/test/CodeGen/X86/prefixdata.ll
@@ -0,0 +1,15 @@
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s
+
+@i = linkonce_odr global i32 1
+
+; CHECK: f:
+; CHECK-NEXT: .long	1
+define void @f() prefix i32 1 {
+  ret void
+}
+
+; CHECK: g:
+; CHECK-NEXT: .quad	i
+define void @g() prefix i32* @i {
+  ret void
+}