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| ; RUN: opt < %s -S -loop-unroll -verify-loop-info | FileCheck %s
; RUN: opt < %s -S -passes='require<opt-remark-emit>,unroll,verify<loops>' | FileCheck %s
;
; Unit tests for LoopInfo::markAsRemoved.
declare i1 @check() nounwind
; Ensure that tail->inner is removed and rely on verify-loopinfo to
; check soundness.
;
; CHECK-LABEL: @skiplevelexit(
; CHECK: tail:
; CHECK-NOT: br
; CHECK: ret void
define void @skiplevelexit() nounwind {
entry:
br label %outer
outer:
br label %inner
inner:
%iv = phi i32 [ 0, %outer ], [ %inc, %tail ]
%inc = add i32 %iv, 1
call zeroext i1 @check()
br i1 true, label %outer.backedge, label %tail
tail:
br i1 false, label %inner, label %exit
outer.backedge:
br label %outer
exit:
ret void
}
; Remove the middle loop of a triply nested loop tree.
; Ensure that only the middle loop is removed and rely on verify-loopinfo to
; check soundness.
;
; CHECK-LABEL: @unloopNested(
; Outer loop control.
; CHECK: while.body:
; CHECK: br i1 %cmp3, label %if.then, label %if.end
; Inner loop control.
; CHECK: while.end14.i:
; CHECK: br i1 %call15.i, label %if.end.i, label %exit
; Middle loop control should no longer reach %while.cond.
; Now it is the outer loop backedge.
; CHECK: exit:
; CHECK: br label %while.cond.outer
define void @unloopNested() {
entry:
br label %while.cond.outer
while.cond.outer:
br label %while.cond
while.cond:
%cmp = call zeroext i1 @check()
br i1 %cmp, label %while.body, label %while.end
while.body:
%cmp3 = call zeroext i1 @check()
br i1 %cmp3, label %if.then, label %if.end
if.then:
br label %return
if.end:
%cmp.i48 = call zeroext i1 @check()
br i1 %cmp.i48, label %if.then.i, label %if.else20.i
if.then.i:
%cmp8.i = call zeroext i1 @check()
br i1 %cmp8.i, label %merge, label %if.else.i
if.else.i:
br label %merge
if.else20.i:
%cmp25.i = call zeroext i1 @check()
br i1 %cmp25.i, label %merge, label %if.else28.i
if.else28.i:
br label %merge
merge:
br label %while.cond2.i
while.cond2.i:
%cmp.i = call zeroext i1 @check()
br i1 %cmp.i, label %while.cond2.backedge.i, label %while.end.i
while.cond2.backedge.i:
br label %while.cond2.i
while.end.i:
%cmp1114.i = call zeroext i1 @check()
br i1 %cmp1114.i, label %while.body12.lr.ph.i, label %while.end14.i
while.body12.lr.ph.i:
br label %while.end14.i
while.end14.i:
%call15.i = call zeroext i1 @check()
br i1 %call15.i, label %if.end.i, label %exit
if.end.i:
br label %while.cond2.backedge.i
exit:
br i1 false, label %while.cond, label %if.else
if.else:
br label %while.cond.outer
while.end:
br label %return
return:
ret void
}
; Remove the middle loop of a deeply nested loop tree.
; Ensure that only the middle loop is removed and rely on verify-loopinfo to
; check soundness.
;
; This test must be disabled until trip count computation can be optimized...
; rdar:14038809 [SCEV]: Optimize trip count computation for multi-exit loops.
; CHECKFIXME-LABEL: @unloopDeepNested(
; Inner-inner loop control.
; CHECKFIXME: while.cond.us.i:
; CHECKFIXME: br i1 %cmp.us.i, label %next_data.exit, label %while.body.us.i
; CHECKFIXME: if.then.us.i:
; CHECKFIXME: br label %while.cond.us.i
; Inner loop tail.
; CHECKFIXME: if.else.i:
; CHECKFIXME: br label %while.cond.outer.i
; Middle loop control (removed).
; CHECKFIXME: valid_data.exit:
; CHECKFIXME-NOT: br
; CHECKFIXME: %cmp = call zeroext i1 @check()
; Outer loop control.
; CHECKFIXME: copy_data.exit:
; CHECKFIXME: br i1 %cmp38, label %if.then39, label %while.cond.outer
; Outer-outer loop tail.
; CHECKFIXME: while.cond.outer.outer.backedge:
; CHECKFIXME: br label %while.cond.outer.outer
define void @unloopDeepNested() nounwind {
for.cond8.preheader.i:
%cmp113.i = call zeroext i1 @check()
br i1 %cmp113.i, label %make_data.exit, label %for.body13.lr.ph.i
for.body13.lr.ph.i:
br label %make_data.exit
make_data.exit:
br label %while.cond.outer.outer
while.cond.outer.outer:
br label %while.cond.outer
while.cond.outer:
br label %while.cond
while.cond:
br label %while.cond.outer.i
while.cond.outer.i:
%tmp192.ph.i = call zeroext i1 @check()
br i1 %tmp192.ph.i, label %while.cond.outer.split.us.i, label %while.body.loopexit
while.cond.outer.split.us.i:
br label %while.cond.us.i
while.cond.us.i:
%cmp.us.i = call zeroext i1 @check()
br i1 %cmp.us.i, label %next_data.exit, label %while.body.us.i
while.body.us.i:
%cmp7.us.i = call zeroext i1 @check()
br i1 %cmp7.us.i, label %if.then.us.i, label %if.else.i
if.then.us.i:
br label %while.cond.us.i
if.else.i:
br label %while.cond.outer.i
next_data.exit:
%tmp192.ph.i.lcssa28 = call zeroext i1 @check()
br i1 %tmp192.ph.i.lcssa28, label %while.end, label %while.body
while.body.loopexit:
br label %while.body
while.body:
br label %while.cond.i
while.cond.i:
%cmp.i = call zeroext i1 @check()
br i1 %cmp.i, label %valid_data.exit, label %while.body.i
while.body.i:
%cmp7.i = call zeroext i1 @check()
br i1 %cmp7.i, label %valid_data.exit, label %if.end.i
if.end.i:
br label %while.cond.i
valid_data.exit:
br i1 true, label %if.then, label %while.cond
if.then:
%cmp = call zeroext i1 @check()
br i1 %cmp, label %if.then12, label %if.end
if.then12:
br label %if.end
if.end:
%tobool3.i = call zeroext i1 @check()
br i1 %tobool3.i, label %copy_data.exit, label %while.body.lr.ph.i
while.body.lr.ph.i:
br label %copy_data.exit
copy_data.exit:
%cmp38 = call zeroext i1 @check()
br i1 %cmp38, label %if.then39, label %while.cond.outer
if.then39:
%cmp5.i = call zeroext i1 @check()
br i1 %cmp5.i, label %while.cond.outer.outer.backedge, label %for.cond8.preheader.i8.thread
for.cond8.preheader.i8.thread:
br label %while.cond.outer.outer.backedge
while.cond.outer.outer.backedge:
br label %while.cond.outer.outer
while.end:
ret void
}
; Remove a nested loop with irreducible control flow.
; Ensure that only the middle loop is removed and rely on verify-loopinfo to
; check soundness.
;
; CHECK-LABEL: @unloopIrreducible(
; Irreducible loop.
; CHECK: for.inc117:
; CHECK: br label %for.cond103t
; Nested loop (removed).
; CHECK: for.inc159:
; CHECK: br label %for.inc163
define void @unloopIrreducible() nounwind {
entry:
br label %for.body
for.body:
%cmp2113 = call zeroext i1 @check()
br i1 %cmp2113, label %for.body22.lr.ph, label %for.inc163
for.body22.lr.ph:
br label %for.body22
for.body22:
br label %for.body33
for.body33:
br label %for.end
for.end:
%cmp424 = call zeroext i1 @check()
br i1 %cmp424, label %for.body43.lr.ph, label %for.end93
for.body43.lr.ph:
br label %for.end93
for.end93:
%cmp96 = call zeroext i1 @check()
br i1 %cmp96, label %if.then97, label %for.cond103
if.then97:
br label %for.cond103t
for.cond103t:
br label %for.cond103
for.cond103:
%cmp105 = call zeroext i1 @check()
br i1 %cmp105, label %for.body106, label %for.end120
for.body106:
%cmp108 = call zeroext i1 @check()
br i1 %cmp108, label %if.then109, label %for.inc117
if.then109:
br label %for.inc117
for.inc117:
br label %for.cond103t
for.end120:
br label %for.inc159
for.inc159:
br i1 false, label %for.body22, label %for.cond15.for.inc163_crit_edge
for.cond15.for.inc163_crit_edge:
br label %for.inc163
for.inc163:
%cmp12 = call zeroext i1 @check()
br i1 %cmp12, label %for.body, label %for.end166
for.end166:
ret void
}
; Remove a loop whose exit branches into a sibling loop.
; Ensure that only the loop is removed and rely on verify-loopinfo to
; check soundness.
;
; CHECK-LABEL: @unloopCriticalEdge(
; CHECK: while.cond.outer.i.loopexit.split:
; CHECK: br label %while.body
; CHECK: while.body:
; CHECK: br label %for.end78
define void @unloopCriticalEdge() nounwind {
entry:
br label %for.cond31
for.cond31:
br i1 undef, label %for.body35, label %for.end94
for.body35:
br label %while.cond.i.preheader
while.cond.i.preheader:
br i1 undef, label %while.cond.i.preheader.split, label %while.cond.outer.i.loopexit.split
while.cond.i.preheader.split:
br label %while.cond.i
while.cond.i:
br i1 true, label %while.cond.i, label %while.cond.outer.i.loopexit
while.cond.outer.i.loopexit:
br label %while.cond.outer.i.loopexit.split
while.cond.outer.i.loopexit.split:
br i1 false, label %while.cond.i.preheader, label %Func2.exit
Func2.exit:
br label %while.body
while.body:
br i1 false, label %while.body, label %while.end
while.end:
br label %for.end78
for.end78:
br i1 undef, label %Proc2.exit, label %for.cond.i.preheader
for.cond.i.preheader:
br label %for.cond.i
for.cond.i:
br label %for.cond.i
Proc2.exit:
br label %for.cond31
for.end94:
ret void
}
; Test UnloopUpdater::removeBlocksFromAncestors.
;
; Check that the loop backedge is removed from the middle loop 1699,
; but not the inner loop 1676.
; CHECK: while.body1694:
; CHECK: unreachable
; CHECK: while.end1699:
; CHECK: br label %sw.default1711
define void @removeSubloopBlocks() nounwind {
entry:
br label %tryagain.outer
tryagain.outer: ; preds = %sw.bb304, %entry
br label %tryagain
tryagain: ; preds = %while.end1699, %tryagain.outer
br i1 undef, label %sw.bb1669, label %sw.bb304
sw.bb304: ; preds = %tryagain
br i1 undef, label %return, label %tryagain.outer
sw.bb1669: ; preds = %tryagain
br i1 undef, label %sw.default1711, label %while.cond1676
while.cond1676: ; preds = %while.body1694, %sw.bb1669
br i1 undef, label %while.end1699, label %while.body1694
while.body1694: ; preds = %while.cond1676
br label %while.cond1676
while.end1699: ; preds = %while.cond1676
br i1 false, label %tryagain, label %sw.default1711
sw.default1711: ; preds = %while.end1699, %sw.bb1669, %tryagain
br label %defchar
defchar: ; preds = %sw.default1711, %sw.bb376
br i1 undef, label %if.end2413, label %if.then2368
if.then2368: ; preds = %defchar
unreachable
if.end2413: ; preds = %defchar
unreachable
return: ; preds = %sw.bb304
ret void
}
; PR11335: the most deeply nested block should be removed from the outer loop.
; CHECK-LABEL: @removeSubloopBlocks2(
; CHECK: for.cond3:
; CHECK-NOT: br
; CHECK: ret void
define void @removeSubloopBlocks2() nounwind {
entry:
%tobool.i = icmp ne i32 undef, 0
br label %lbl_616
lbl_616.loopexit: ; preds = %for.cond
br label %lbl_616
lbl_616: ; preds = %lbl_616.loopexit, %entry
br label %for.cond
for.cond: ; preds = %for.cond3, %lbl_616
br i1 false, label %for.cond1.preheader, label %lbl_616.loopexit
for.cond1.preheader: ; preds = %for.cond
br label %for.cond1
for.cond1.loopexit: ; preds = %for.cond.i
br label %for.cond1
for.cond1: ; preds = %for.cond1.loopexit, %for.cond1.preheader
br i1 false, label %for.body2, label %for.cond3
for.body2: ; preds = %for.cond1
br label %for.cond.i
for.cond.i: ; preds = %for.cond.i, %for.body2
br i1 %tobool.i, label %for.cond.i, label %for.cond1.loopexit
for.cond3: ; preds = %for.cond1
br i1 false, label %for.cond, label %if.end
if.end: ; preds = %for.cond3
ret void
}
|