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      1 ; RUN: opt < %s -gvn -S | FileCheck %s
      2 
      3 target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:32-f32:32:32-f64:32:32-v64:64:64-v128:128:128-a0:0:32-n32"
      4 
      5 @p = external global i32
      6 
      7 define i32 @test(i32 %n) nounwind {
      8 ; CHECK: @test
      9 entry:
     10   br label %for.cond
     11 
     12 ; loads aligned greater than the memory should not be moved past conditionals
     13 ; CHECK-NOT: load
     14 ; CHECK: br i1
     15 
     16 for.cond:
     17   %i.0 = phi i32 [ 0, %entry ], [ %indvar.next, %for.inc ]
     18   %cmp = icmp slt i32 %i.0, %n
     19   br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge
     20 
     21 for.cond.for.end_crit_edge:
     22 ; ...but PRE can still move the load out of for.end to here.
     23 ; CHECK: for.cond.for.end_crit_edge:
     24 ; CHECK-NEXT: load
     25   br label %for.end
     26 
     27 for.body:
     28   %tmp3 = load i32* @p, align 8
     29   %dec = add i32 %tmp3, -1
     30   store i32 %dec, i32* @p
     31   %cmp6 = icmp slt i32 %dec, 0
     32   br i1 %cmp6, label %for.body.for.end_crit_edge, label %for.inc
     33 
     34 for.body.for.end_crit_edge:
     35   br label %for.end
     36 
     37 for.inc:
     38   %indvar.next = add i32 %i.0, 1
     39   br label %for.cond
     40 
     41 for.end:
     42   %tmp9 = load i32* @p, align 8
     43   ret i32 %tmp9
     44 }
     45