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      1 ; RUN: opt < %s -S -basicaa -licm | FileCheck %s
      2 
      3 ; Check that we can hoist unordered loads
      4 define i32 @test1(i32* nocapture %y) nounwind uwtable ssp {
      5 entry:
      6   br label %loop
      7 
      8 loop:
      9   %i = phi i32 [ %inc, %loop ], [ 0, %entry ]
     10   %val = load atomic i32, i32* %y unordered, align 4
     11   %inc = add nsw i32 %i, 1
     12   %exitcond = icmp eq i32 %inc, %val
     13   br i1 %exitcond, label %end, label %loop
     14 
     15 end:
     16   ret i32 %val
     17 ; CHECK-LABEL: define i32 @test1(
     18 ; CHECK: load atomic
     19 ; CHECK-NEXT: br label %loop
     20 }
     21 
     22 ; Check that we don't sink/hoist monotonic loads
     23 ; (Strictly speaking, it's not forbidden, but it's supposed to be possible to
     24 ; use monotonic for spinlock-like constructs.)
     25 define i32 @test2(i32* nocapture %y) nounwind uwtable ssp {
     26 entry:
     27   br label %loop
     28 
     29 loop:
     30   %val = load atomic i32, i32* %y monotonic, align 4
     31   %exitcond = icmp ne i32 %val, 0
     32   br i1 %exitcond, label %end, label %loop
     33 
     34 end:
     35   ret i32 %val
     36 ; CHECK-LABEL: define i32 @test2(
     37 ; CHECK: load atomic
     38 ; CHECK-NEXT: %exitcond = icmp ne
     39 ; CHECK-NEXT: br i1 %exitcond, label %end, label %loop
     40 }
     41 
     42 ; Check that we hoist unordered around monotonic.
     43 ; (The noalias shouldn't be necessary in theory, but LICM isn't quite that
     44 ; smart yet.)
     45 define i32 @test3(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
     46 entry:
     47   br label %loop
     48 
     49 loop:
     50   %vala = load atomic i32, i32* %y monotonic, align 4
     51   %valb = load atomic i32, i32* %x unordered, align 4
     52   %exitcond = icmp ne i32 %vala, %valb
     53   br i1 %exitcond, label %end, label %loop
     54 
     55 end:
     56   ret i32 %vala
     57 ; CHECK-LABEL: define i32 @test3(
     58 ; CHECK: load atomic i32, i32* %x unordered
     59 ; CHECK-NEXT: br label %loop
     60 }
     61 
     62 ; Don't try to "sink" unordered stores yet; it is legal, but the machinery
     63 ; isn't there.
     64 define i32 @test4(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
     65 entry:
     66   br label %loop
     67 
     68 loop:
     69   %vala = load atomic i32, i32* %y monotonic, align 4
     70   store atomic i32 %vala, i32* %x unordered, align 4
     71   %exitcond = icmp ne i32 %vala, 0
     72   br i1 %exitcond, label %end, label %loop
     73 
     74 end:
     75   ret i32 %vala
     76 ; CHECK-LABEL: define i32 @test4(
     77 ; CHECK: load atomic i32, i32* %y monotonic
     78 ; CHECK-NEXT: store atomic
     79 }
     80