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      1 ; RUN: opt < %s -S -basicaa -licm | FileCheck %s
      2 ; RUN: opt -aa-pipeline=basic-aa -passes='lcssa,require<aa>,require<targetir>,require<scalar-evolution>,loop(licm)' < %s -S | FileCheck %s
      3 
      4 ; Check that we can hoist unordered loads
      5 define i32 @test1(i32* nocapture %y) nounwind uwtable ssp {
      6 entry:
      7   br label %loop
      8 
      9 loop:
     10   %i = phi i32 [ %inc, %loop ], [ 0, %entry ]
     11   %val = load atomic i32, i32* %y unordered, align 4
     12   %inc = add nsw i32 %i, 1
     13   %exitcond = icmp eq i32 %inc, %val
     14   br i1 %exitcond, label %end, label %loop
     15 
     16 end:
     17   ret i32 %val
     18 ; CHECK-LABEL: define i32 @test1(
     19 ; CHECK: load atomic
     20 ; CHECK-NEXT: br label %loop
     21 }
     22 
     23 ; Check that we don't sink/hoist monotonic loads
     24 ; (Strictly speaking, it's not forbidden, but it's supposed to be possible to
     25 ; use monotonic for spinlock-like constructs.)
     26 define i32 @test2(i32* nocapture %y) nounwind uwtable ssp {
     27 entry:
     28   br label %loop
     29 
     30 loop:
     31   %val = load atomic i32, i32* %y monotonic, align 4
     32   %exitcond = icmp ne i32 %val, 0
     33   br i1 %exitcond, label %end, label %loop
     34 
     35 end:
     36   ret i32 %val
     37 ; CHECK-LABEL: define i32 @test2(
     38 ; CHECK: load atomic
     39 ; CHECK-NEXT: %exitcond = icmp ne
     40 ; CHECK-NEXT: br i1 %exitcond, label %end, label %loop
     41 }
     42 
     43 ; Check that we hoist unordered around monotonic.
     44 ; (The noalias shouldn't be necessary in theory, but LICM isn't quite that
     45 ; smart yet.)
     46 define i32 @test3(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
     47 entry:
     48   br label %loop
     49 
     50 loop:
     51   %vala = load atomic i32, i32* %y monotonic, align 4
     52   %valb = load atomic i32, i32* %x unordered, align 4
     53   %exitcond = icmp ne i32 %vala, %valb
     54   br i1 %exitcond, label %end, label %loop
     55 
     56 end:
     57   ret i32 %vala
     58 ; CHECK-LABEL: define i32 @test3(
     59 ; CHECK: load atomic i32, i32* %x unordered
     60 ; CHECK-NEXT: br label %loop
     61 }
     62 
     63 ; Don't try to "sink" unordered stores yet; it is legal, but the machinery
     64 ; isn't there.
     65 define i32 @test4(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
     66 entry:
     67   br label %loop
     68 
     69 loop:
     70   %vala = load atomic i32, i32* %y monotonic, align 4
     71   store atomic i32 %vala, i32* %x unordered, align 4
     72   %exitcond = icmp ne i32 %vala, 0
     73   br i1 %exitcond, label %end, label %loop
     74 
     75 end:
     76   ret i32 %vala
     77 ; CHECK-LABEL: define i32 @test4(
     78 ; CHECK: load atomic i32, i32* %y monotonic
     79 ; CHECK-NEXT: store atomic
     80 }
     81