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