Expand test to weak symbols.

Author: rlavaee

llvm/test/CodeGen/X86/basic-block-sections-code-prefetch.ll

@@ -7,6 +7,9 @@
 ; RUN: echo 't 1@0' >> %t
 ; RUN: echo 't 1@1' >> %t
 ; RUN: echo 't 2@1' >> %t
+; RUN: echo 'f _Z3barv' >> %t
+; RUN: echo 't 0@0' >> %t
+; RUN: echo 't 21@1' >> %t
 ;;
 ; RUN: llc < %s -mtriple=x86_64-pc-linux -asm-verbose=false -function-sections -basic-block-sections=%t  | FileCheck %s
 
@@ -47,5 +50,12 @@ define i32 @_Z3foob(i1 zeroext %0) nounwind {
   ret i32 %14
 }
 
-declare i32 @_Z3barv() #1
+define weak i32 @_Z3barv() nounwind {
+  %1 = call i32 @_Z3bazv()
+  ret i32 %1
+; CHECK:      _Z3barv:
+; CHECK-NEXT:   .weak __llvm_prefetch_target__Z3barv_0_0
+; CHECK-NEXT: __llvm_prefetch_target__Z3barv_0_0:
+}
+
 declare i32 @_Z3bazv() #1