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      1 ; RUN: opt < %s -globalopt -S | FileCheck %s
      2 
      3 declare void @wait()
      4 declare void @signal()
      5 declare void @start_thread(void ()*)
      6 
      7 @x = internal thread_local global [100 x i32] zeroinitializer, align 16
      8 @ip = internal global i32* null, align 8
      9 
     10 ; PR14309: GlobalOpt would think that the value of @ip is always the address of
     11 ; x[1]. However, that address is different for different threads so @ip cannot
     12 ; be replaced with a constant.
     13 
     14 define i32 @f() {
     15 entry:
     16   ; Set @ip to point to x[1] for thread 1.
     17   store i32* getelementptr inbounds ([100 x i32]* @x, i64 0, i64 1), i32** @ip, align 8
     18 
     19   ; Run g on a new thread.
     20   tail call void @start_thread(void ()* @g) nounwind
     21   tail call void @wait() nounwind
     22 
     23   ; Reset x[1] for thread 1.
     24   store i32 0, i32* getelementptr inbounds ([100 x i32]* @x, i64 0, i64 1), align 4
     25 
     26   ; Read the value of @ip, which now points at x[1] for thread 2.
     27   %0 = load i32** @ip, align 8
     28 
     29   %1 = load i32* %0, align 4
     30   ret i32 %1
     31 
     32 ; CHECK: @f
     33 ; Make sure that the load from @ip hasn't been removed.
     34 ; CHECK: load i32** @ip
     35 ; CHECK: ret
     36 }
     37 
     38 define internal void @g() nounwind uwtable {
     39 entry:
     40   ; Set @ip to point to x[1] for thread 2.
     41   store i32* getelementptr inbounds ([100 x i32]* @x, i64 0, i64 1), i32** @ip, align 8
     42 
     43   ; Store 50 in x[1] for thread 2.
     44   store i32 50, i32* getelementptr inbounds ([100 x i32]* @x, i64 0, i64 1), align 4
     45 
     46   tail call void @signal() nounwind
     47   ret void
     48 
     49 ; CHECK: @g
     50 ; Make sure that the store to @ip hasn't been removed.
     51 ; CHECK: store {{.*}} @ip
     52 ; CHECK: ret
     53 }
     54