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; RUN: opt < %s -passes=gvn -S | FileCheck %s
; RUN: opt < %s -passes="gvn<load-pre>" -S | FileCheck %s
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"
@p = external global i32
define i32 @test(i32 %n) nounwind {
; CHECK-LABEL: @test(
entry:
br label %for.cond
; loads aligned greater than the memory should not be moved past conditionals
; CHECK-NOT: load
; CHECK: br i1
for.cond:
%i.0 = phi i32 [ 0, %entry ], [ %indvar.next, %for.inc ]
%cmp = icmp slt i32 %i.0, %n
br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge
for.cond.for.end_crit_edge:
; ...but PRE can still move the load out of for.end to here.
; CHECK: for.cond.for.end_crit_edge:
; CHECK-NEXT: load
br label %for.end
for.body:
%tmp3 = load i32, ptr @p, align 8
%dec = add i32 %tmp3, -1
store i32 %dec, ptr @p
%cmp6 = icmp slt i32 %dec, 0
br i1 %cmp6, label %for.body.for.end_crit_edge, label %for.inc
for.body.for.end_crit_edge:
br label %for.end
for.inc:
%indvar.next = add i32 %i.0, 1
br label %for.cond
for.end:
%tmp9 = load i32, ptr @p, align 8
ret i32 %tmp9
}
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