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| ; RUN: opt -licm -basicaa < %s -S | FileCheck %s
; RUN: opt -aa-pipeline=basic-aa -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s
define void @f_0(i1 %p) nounwind ssp {
; CHECK-LABEL: @f_0(
entry:
br label %for.body
for.body:
br i1 undef, label %if.then, label %for.cond.backedge
for.cond.backedge:
br i1 undef, label %for.end104, label %for.body
if.then:
br i1 undef, label %if.then27, label %if.end.if.end.split_crit_edge.critedge
if.then27:
; CHECK: tail call void @llvm.assume
tail call void @llvm.assume(i1 %p)
br label %for.body61.us
if.end.if.end.split_crit_edge.critedge:
br label %for.body61
for.body61.us:
br i1 undef, label %for.cond.backedge, label %for.body61.us
for.body61:
br i1 undef, label %for.cond.backedge, label %for.body61
for.end104:
ret void
}
define void @f_1(i1 %cond, i32* %ptr) {
; CHECK-LABEL: @f_1(
; CHECK-LABEL: entry:
; CHECK: call void @llvm.assume(i1 %cond)
; CHECK: %val = load i32, i32* %ptr
; CHECK-LABEL: loop:
entry:
br label %loop
loop:
%x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
call void @llvm.assume(i1 %cond)
%val = load i32, i32* %ptr
%x.inc = add i32 %x, %val
br label %loop
}
; Can't hoist because the call may throw and the assume
; may never execute.
define void @f_2(i1 %cond, i32* %ptr) {
; CHECK-LABEL: @f_2(
; CHECK-LABEL: entry:
; CHECK-LABEL: loop:
; CHECK: call void @llvm.assume(i1 %cond)
; CHECK: %val = load i32, i32* %ptr
entry:
br label %loop
loop:
%x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
call void @maythrow()
call void @llvm.assume(i1 %cond)
%val = load i32, i32* %ptr
%x.inc = add i32 %x, %val
br label %loop
}
; Note: resulting loop could be peeled and then hoisted, but
; by default assume is captured in phi cycle.
define void @f_3(i1 %cond, i32* %ptr) {
; CHECK-LABEL: @f_3(
; CHECK-LABEL: entry:
; CHECK: %val = load i32, i32* %ptr
; CHECK-LABEL: loop:
; CHECK: call void @llvm.assume(i1 %x.cmp)
entry:
br label %loop
loop:
%x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
%x.cmp = phi i1 [%cond, %entry], [%cond.next, %loop]
call void @llvm.assume(i1 %x.cmp)
%val = load i32, i32* %ptr
%cond.next = icmp eq i32 %val, 5
%x.inc = add i32 %x, %val
br label %loop
}
declare void @maythrow()
declare void @llvm.assume(i1)
|