; RUN: opt -S < %s -passes='print<scalar-evolution>,loop-simplify,print<scalar-evolution>' 2>&1 | FileCheck %s
; Provide legal integer types.
target datalayout = "n8:16:32:64"
@maxStat = external global i32
; LoopSimplify should invalidate SCEV when splitting out the
; inner loop.
;
; First SCEV print:
; CHECK-LABEL: Classifying expressions for: @test
; CHECK: %[[PHI:.*]] = phi i32 [ 0, %entry ], [ %{{.*}}, %if.then5 ], [ %[[PHI]], %if.end ]
; CHECK-LABEL: Determining loop execution counts for: @test
; CHECK: Loop %for.body18: Unpredictable backedge-taken count.
; CHECK: Loop %for.body18: max backedge-taken count is 2147483646
; CHECK: Loop %for.body18: Unpredictable predicated backedge-taken count.
; CHECK: Loop %for.cond: <multiple exits> Unpredictable backedge-taken count.
; CHECK: Loop %for.cond: Unpredictable max backedge-taken count.
; CHECK: Loop %for.cond: Unpredictable predicated backedge-taken count.
;
; Now simplify the loop, which should cause SCEV to re-compute more precise
; info here in addition to having preheader PHIs. Second SCEV print:
; CHECK-LABEL: Classifying expressions for: @test
; CHECK: phi i32 [ %{{.*}}, %if.then5 ], [ 0, %entry ]
; CHECK-LABEL: Determining loop execution counts for: @test
; CHECK: Loop %for.body18: Unpredictable backedge-taken count.
; CHECK: Loop %for.body18: max backedge-taken count is 2147483646
; CHECK: Loop %for.body18: Unpredictable predicated backedge-taken count.
; CHECK: Loop %for.cond: <multiple exits> Unpredictable backedge-taken count.
; CHECK: Loop %for.cond: max backedge-taken count is -2147483647
; CHECK: Loop %for.cond: Unpredictable predicated backedge-taken count.
; CHECK: Loop %for.cond.outer: <multiple exits> Unpredictable backedge-taken count.
; CHECK: Loop %for.cond.outer: Unpredictable max backedge-taken count.
; CHECK: Loop %for.cond.outer: Unpredictable predicated backedge-taken count.
define i32 @test() nounwind {
entry:
br label %for.cond
for.cond: ; preds = %if.then5, %if.end, %entry
%cuts.1 = phi i32 [ 0, %entry ], [ %inc, %if.then5 ], [ %cuts.1, %if.end ]
%0 = phi i32 [ 0, %entry ], [ %add, %if.end ], [ %add, %if.then5 ]
%add = add i32 %0, 1
%cmp = icmp slt i32 %0, 1
%tmp1 = load i32, i32* @maxStat, align 4
br i1 %cmp, label %for.body, label %for.cond14.preheader
for.cond14.preheader: ; preds = %for.cond
%cmp1726 = icmp sgt i32 %tmp1, 0
br i1 %cmp1726, label %for.body18, label %return
for.body: ; preds = %for.cond
%cmp2 = icmp sgt i32 %tmp1, 100
br i1 %cmp2, label %return, label %if.end
if.end: ; preds = %for.body
%cmp4 = icmp sgt i32 %tmp1, -1
br i1 %cmp4, label %if.then5, label %for.cond
if.then5: ; preds = %if.end
call void @foo() nounwind
%inc = add i32 %cuts.1, 1
br label %for.cond
for.body18: ; preds = %for.body18, %for.cond14.preheader
%i13.027 = phi i32 [ %1, %for.body18 ], [ 0, %for.cond14.preheader ]
call void @foo() nounwind
%1 = add nsw i32 %i13.027, 1
%tmp16 = load i32, i32* @maxStat, align 4
%cmp17 = icmp slt i32 %1, %tmp16
br i1 %cmp17, label %for.body18, label %return
return: ; preds = %for.body18, %for.body, %for.cond14.preheader
ret i32 0
}
declare void @foo() nounwind
; Notify SCEV when removing an ExitingBlock. This only changes the
; backedge-taken information.
;
; First SCEV print:
; CHECK-LABEL: Determining loop execution counts for: @mergeExit
; CHECK: Loop %while.cond191: <multiple exits> Unpredictable backedge-taken count.
; CHECK: Loop %while.cond191: max backedge-taken count is -1
; CHECK: Loop %while.cond191: Unpredictable predicated backedge-taken count.
; CHECK: Loop %while.cond191.outer: <multiple exits> Unpredictable backedge-taken count.
; CHECK: Loop %while.cond191.outer: Unpredictable max backedge-taken count.
; CHECK: Loop %while.cond191.outer: Unpredictable predicated backedge-taken count.
;
; After simplifying, the max backedge count is refined.
; Second SCEV print:
; CHECK-LABEL: Determining loop execution counts for: @mergeExit
; CHECK: Loop %while.cond191: <multiple exits> backedge-taken count is 0
; CHECK: Loop %while.cond191: max backedge-taken count is 0
; CHECK: Loop %while.cond191: Predicated backedge-taken count is 0
; CHECK: Loop %while.cond191.outer: <multiple exits> Unpredictable backedge-taken count.
; CHECK: Loop %while.cond191.outer: max backedge-taken count is false
; CHECK: Loop %while.cond191.outer: Unpredictable predicated backedge-taken count.
define void @mergeExit(i32 %MapAttrCount) nounwind uwtable ssp {
entry:
br i1 undef, label %if.then124, label %if.end126
if.then124: ; preds = %entry
unreachable
if.end126: ; preds = %entry
br i1 undef, label %while.body.lr.ph, label %if.end591
while.body.lr.ph: ; preds = %if.end126
br i1 undef, label %if.end140, label %if.then137
if.then137: ; preds = %while.body.lr.ph
unreachable
if.end140: ; preds = %while.body.lr.ph
br i1 undef, label %while.cond191.outer, label %if.then148
if.then148: ; preds = %if.end140
unreachable
while.cond191.outer: ; preds = %if.then205, %if.end140
br label %while.cond191
while.cond191: ; preds = %while.body197, %while.cond191.outer
%CppIndex.0 = phi i32 [ %inc, %while.body197 ], [ undef, %while.cond191.outer ]
br i1 undef, label %land.rhs, label %if.then216
land.rhs: ; preds = %while.cond191
%inc = add i32 %CppIndex.0, 1
%cmp196 = icmp ult i32 %inc, %MapAttrCount
br i1 %cmp196, label %while.body197, label %if.then216
while.body197: ; preds = %land.rhs
br i1 undef, label %if.then205, label %while.cond191
if.then205: ; preds = %while.body197
br label %while.cond191.outer
if.then216: ; preds = %land.rhs, %while.cond191
br i1 undef, label %if.else, label %if.then221
if.then221: ; preds = %if.then216
unreachable
if.else: ; preds = %if.then216
br i1 undef, label %if.then266, label %if.end340
if.then266: ; preds = %if.else
switch i32 undef, label %if.else329 [
i32 17, label %if.then285
i32 19, label %if.then285
i32 18, label %if.then285
i32 15, label %if.then285
]
if.then285: ; preds = %if.then266, %if.then266, %if.then266, %if.then266
br i1 undef, label %if.then317, label %if.else324
if.then317: ; preds = %if.then285
br label %if.end340
if.else324: ; preds = %if.then285
unreachable
if.else329: ; preds = %if.then266
unreachable
if.end340: ; preds = %if.then317, %if.else
unreachable
if.end591: ; preds = %if.end126
br i1 undef, label %cond.end, label %cond.false
cond.false: ; preds = %if.end591
unreachable
cond.end: ; preds = %if.end591
ret void
}