llvm/llvm/test/Analysis/BranchProbabilityInfo/loop.ll

; Test the static branch probability heuristics for no-return functions.
; RUN: opt < %s -passes='print<branch-prob>' --disable-output 2>&1 | FileCheck %s

declare void @g1()
declare void @g2()
declare void @g3()
declare void @g4()
declare i32 @g5()

define void @test1(i32 %a, i32 %b) {
entry:
  br label %do.body
; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

do.body:
  %i.0 = phi i32 [ 0, %entry ], [ %inc3, %do.end ]
  call void @g1()
  br label %do.body1
; CHECK: edge %do.body -> %do.body1 probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

do.body1:
  %j.0 = phi i32 [ 0, %do.body ], [ %inc, %do.body1 ]
  call void @g2()
  %inc = add nsw i32 %j.0, 1
  %cmp = icmp slt i32 %inc, %b
  br i1 %cmp, label %do.body1, label %do.end
; CHECK: edge %do.body1 -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %do.body1 -> %do.end probability is 0x04000000 / 0x80000000 = 3.12%

do.end:
  call void @g3()
  %inc3 = add nsw i32 %i.0, 1
  %cmp4 = icmp slt i32 %inc3, %a
  br i1 %cmp4, label %do.body, label %do.end5
; CHECK: edge %do.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %do.end -> %do.end5 probability is 0x04000000 / 0x80000000 = 3.12%

do.end5:
  call void @g4()
  ret void
}

define void @test2(i32 %a, i32 %b) {
entry:
  %cmp9 = icmp sgt i32 %a, 0
  br i1 %cmp9, label %for.body.lr.ph, label %for.end6
; CHECK: edge %entry -> %for.body.lr.ph probability is 0x50000000 / 0x80000000 = 62.50%
; CHECK: edge %entry -> %for.end6 probability is 0x30000000 / 0x80000000 = 37.50%

for.body.lr.ph:
  %cmp27 = icmp sgt i32 %b, 0
  br label %for.body
; CHECK: edge %for.body.lr.ph -> %for.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.body:
  %i.010 = phi i32 [ 0, %for.body.lr.ph ], [ %inc5, %for.end ]
  call void @g1()
  br i1 %cmp27, label %for.body3, label %for.end
; CHECK: edge %for.body -> %for.body3 probability is 0x50000000 / 0x80000000 = 62.50%
; CHECK: edge %for.body -> %for.end probability is 0x30000000 / 0x80000000 = 37.50%

for.body3:
  %j.08 = phi i32 [ %inc, %for.body3 ], [ 0, %for.body ]
  call void @g2()
  %inc = add nsw i32 %j.08, 1
  %exitcond = icmp eq i32 %inc, %b
  br i1 %exitcond, label %for.end, label %for.body3
; CHECK: edge %for.body3 -> %for.end probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %for.body3 -> %for.body3 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

for.end:
  call void @g3()
  %inc5 = add nsw i32 %i.010, 1
  %exitcond11 = icmp eq i32 %inc5, %a
  br i1 %exitcond11, label %for.end6, label %for.body
; CHECK: edge %for.end -> %for.end6 probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %for.end -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

for.end6:
  call void @g4()
  ret void
}

define void @test3(i32 %a, i32 %b, ptr %c) {
entry:
  br label %do.body
; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

do.body:
  %i.0 = phi i32 [ 0, %entry ], [ %inc4, %if.end ]
  call void @g1()
  %0 = load i32, ptr %c, align 4
  %cmp = icmp slt i32 %0, 42
  br i1 %cmp, label %do.body1, label %if.end
; CHECK: edge %do.body -> %do.body1 probability is 0x40000000 / 0x80000000 = 50.00%
; CHECK: edge %do.body -> %if.end probability is 0x40000000 / 0x80000000 = 50.00%

do.body1:
  %j.0 = phi i32 [ %inc, %do.body1 ], [ 0, %do.body ]
  call void @g2()
  %inc = add nsw i32 %j.0, 1
  %cmp2 = icmp slt i32 %inc, %b
  br i1 %cmp2, label %do.body1, label %if.end
; CHECK: edge %do.body1 -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %do.body1 -> %if.end probability is 0x04000000 / 0x80000000 = 3.12%

if.end:
  call void @g3()
  %inc4 = add nsw i32 %i.0, 1
  %cmp5 = icmp slt i32 %inc4, %a
  br i1 %cmp5, label %do.body, label %do.end6
; CHECK: edge %if.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %if.end -> %do.end6 probability is 0x04000000 / 0x80000000 = 3.12%

do.end6:
  call void @g4()
  ret void
}

define void @test4(i32 %a, i32 %b, ptr %c) {
entry:
  br label %do.body
; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

do.body:
  %i.0 = phi i32 [ 0, %entry ], [ %inc4, %do.end ]
  call void @g1()
  %0 = load i32, ptr %c, align 4
  %cmp = icmp slt i32 %0, 42
  br i1 %cmp, label %return, label %do.body1
; CHECK: edge %do.body -> %return probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %do.body -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

do.body1:
  %j.0 = phi i32 [ %inc, %do.body1 ], [ 0, %do.body ]
  call void @g2()
  %inc = add nsw i32 %j.0, 1
  %cmp2 = icmp slt i32 %inc, %b
  br i1 %cmp2, label %do.body1, label %do.end
; CHECK: edge %do.body1 -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %do.body1 -> %do.end probability is 0x04000000 / 0x80000000 = 3.12%

do.end:
  call void @g3()
  %inc4 = add nsw i32 %i.0, 1
  %cmp5 = icmp slt i32 %inc4, %a
  br i1 %cmp5, label %do.body, label %do.end6
; CHECK: edge %do.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %do.end -> %do.end6 probability is 0x04000000 / 0x80000000 = 3.12%

do.end6:
  call void @g4()
  br label %return
; CHECK: edge %do.end6 -> %return probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

return:
  ret void
}

define void @test5(i32 %a, i32 %b, ptr %c) {
entry:
  br label %do.body
; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

do.body:
  %i.0 = phi i32 [ 0, %entry ], [ %inc4, %do.end ]
  call void @g1()
  br label %do.body1
; CHECK: edge %do.body -> %do.body1 probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

do.body1:
  %j.0 = phi i32 [ 0, %do.body ], [ %inc, %if.end ]
  %0 = load i32, ptr %c, align 4
  %cmp = icmp slt i32 %0, 42
  br i1 %cmp, label %return, label %if.end
; CHECK: edge %do.body1 -> %return probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %do.body1 -> %if.end probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

if.end:
  call void @g2()
  %inc = add nsw i32 %j.0, 1
  %cmp2 = icmp slt i32 %inc, %b
  br i1 %cmp2, label %do.body1, label %do.end
; CHECK: edge %if.end -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %if.end -> %do.end probability is 0x04000000 / 0x80000000 = 3.12%

do.end:
  call void @g3()
  %inc4 = add nsw i32 %i.0, 1
  %cmp5 = icmp slt i32 %inc4, %a
  br i1 %cmp5, label %do.body, label %do.end6
; CHECK: edge %do.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %do.end -> %do.end6 probability is 0x04000000 / 0x80000000 = 3.12%

do.end6:
  call void @g4()
  br label %return
; CHECK: edge %do.end6 -> %return probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

return:
  ret void
}

define void @test6(i32 %a, i32 %b, ptr %c) {
entry:
  br label %do.body
; CHECK: edge %entry -> %do.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

do.body:
  %i.0 = phi i32 [ 0, %entry ], [ %inc4, %do.end ]
  call void @g1()
  br label %do.body1
; CHECK: edge %do.body -> %do.body1 probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

do.body1:
  %j.0 = phi i32 [ 0, %do.body ], [ %inc, %do.cond ]
  call void @g2()
  %0 = load i32, ptr %c, align 4
  %cmp = icmp slt i32 %0, 42
  br i1 %cmp, label %return, label %do.cond
; CHECK: edge %do.body1 -> %return probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %do.body1 -> %do.cond probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

do.cond:
  %inc = add nsw i32 %j.0, 1
  %cmp2 = icmp slt i32 %inc, %b
  br i1 %cmp2, label %do.body1, label %do.end
; CHECK: edge %do.cond -> %do.body1 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %do.cond -> %do.end probability is 0x04000000 / 0x80000000 = 3.12%

do.end:
  call void @g3()
  %inc4 = add nsw i32 %i.0, 1
  %cmp5 = icmp slt i32 %inc4, %a
  br i1 %cmp5, label %do.body, label %do.end6
; CHECK: edge %do.end -> %do.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %do.end -> %do.end6 probability is 0x04000000 / 0x80000000 = 3.12%

do.end6:
  call void @g4()
  br label %return
; CHECK: edge %do.end6 -> %return probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

return:
  ret void
}

define void @test7(i32 %a, i32 %b, ptr %c) {
entry:
  %cmp10 = icmp sgt i32 %a, 0
  br i1 %cmp10, label %for.body.lr.ph, label %for.end7
; CHECK: edge %entry -> %for.body.lr.ph probability is 0x50000000 / 0x80000000 = 62.50%
; CHECK: edge %entry -> %for.end7 probability is 0x30000000 / 0x80000000 = 37.50%

for.body.lr.ph:
  %cmp38 = icmp sgt i32 %b, 0
  br label %for.body
; CHECK: edge %for.body.lr.ph -> %for.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.body:
  %i.011 = phi i32 [ 0, %for.body.lr.ph ], [ %inc6, %for.inc5 ]
  %0 = load i32, ptr %c, align 4
  %cmp1 = icmp eq i32 %0, %i.011
  br i1 %cmp1, label %for.inc5, label %if.end
; CHECK: edge %for.body -> %for.inc5 probability is 0x40000000 / 0x80000000 = 50.00%
; CHECK: edge %for.body -> %if.end probability is 0x40000000 / 0x80000000 = 50.00%

if.end:
  call void @g1()
  br i1 %cmp38, label %for.body4, label %for.end
; CHECK: edge %if.end -> %for.body4 probability is 0x50000000 / 0x80000000 = 62.50%
; CHECK: edge %if.end -> %for.end probability is 0x30000000 / 0x80000000 = 37.50%

for.body4:
  %j.09 = phi i32 [ %inc, %for.body4 ], [ 0, %if.end ]
  call void @g2()
  %inc = add nsw i32 %j.09, 1
  %exitcond = icmp eq i32 %inc, %b
  br i1 %exitcond, label %for.end, label %for.body4
; CHECK: edge %for.body4 -> %for.end probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %for.body4 -> %for.body4 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

for.end:
  call void @g3()
  br label %for.inc5
; CHECK: edge %for.end -> %for.inc5 probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.inc5:
  %inc6 = add nsw i32 %i.011, 1
  %exitcond12 = icmp eq i32 %inc6, %a
  br i1 %exitcond12, label %for.end7, label %for.body
; CHECK: edge %for.inc5 -> %for.end7 probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %for.inc5 -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

for.end7:
  call void @g4()
  ret void
}

define void @test8(i32 %a, i32 %b, ptr %c) {
entry:
  %cmp18 = icmp sgt i32 %a, 0
  br i1 %cmp18, label %for.body.lr.ph, label %for.end15
; CHECK: edge %entry -> %for.body.lr.ph probability is 0x50000000 / 0x80000000 = 62.50%
; CHECK: edge %entry -> %for.end15 probability is 0x30000000 / 0x80000000 = 37.50%

for.body.lr.ph:
  %cmp216 = icmp sgt i32 %b, 0
  %arrayidx5 = getelementptr inbounds i32, ptr %c, i64 1
  %arrayidx9 = getelementptr inbounds i32, ptr %c, i64 2
  br label %for.body
; CHECK: edge %for.body.lr.ph -> %for.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.body:
  %i.019 = phi i32 [ 0, %for.body.lr.ph ], [ %inc14, %for.end ]
  call void @g1()
  br i1 %cmp216, label %for.body3, label %for.end
; CHECK: edge %for.body -> %for.body3 probability is 0x50000000 / 0x80000000 = 62.50%
; CHECK: edge %for.body -> %for.end probability is 0x30000000 / 0x80000000 = 37.50%

for.body3:
  %j.017 = phi i32 [ 0, %for.body ], [ %inc, %for.inc ]
  %0 = load i32, ptr %c, align 4
  %cmp4 = icmp eq i32 %0, %j.017
  br i1 %cmp4, label %for.inc, label %if.end
; CHECK: edge %for.body3 -> %for.inc probability is 0x40000000 / 0x80000000 = 50.00%
; CHECK: edge %for.body3 -> %if.end probability is 0x40000000 / 0x80000000 = 50.00%

if.end:
  %1 = load i32, ptr %arrayidx5, align 4
  %cmp6 = icmp eq i32 %1, %j.017
  br i1 %cmp6, label %for.inc, label %if.end8
; CHECK: edge %if.end -> %for.inc probability is 0x40000000 / 0x80000000 = 50.00%
; CHECK: edge %if.end -> %if.end8 probability is 0x40000000 / 0x80000000 = 50.00%

if.end8:
  %2 = load i32, ptr %arrayidx9, align 4
  %cmp10 = icmp eq i32 %2, %j.017
  br i1 %cmp10, label %for.inc, label %if.end12
; CHECK: edge %if.end8 -> %for.inc probability is 0x40000000 / 0x80000000 = 50.00%
; CHECK: edge %if.end8 -> %if.end12 probability is 0x40000000 / 0x80000000 = 50.00%

if.end12:
  call void @g2()
  br label %for.inc
; CHECK: edge %if.end12 -> %for.inc probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.inc:
  %inc = add nsw i32 %j.017, 1
  %exitcond = icmp eq i32 %inc, %b
  br i1 %exitcond, label %for.end, label %for.body3
; CHECK: edge %for.inc -> %for.end probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %for.inc -> %for.body3 probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

for.end:
  call void @g3()
  %inc14 = add nsw i32 %i.019, 1
  %exitcond20 = icmp eq i32 %inc14, %a
  br i1 %exitcond20, label %for.end15, label %for.body
; CHECK: edge %for.end -> %for.end15 probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %for.end -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]

for.end15:
  call void @g4()
  ret void
}

; Test that an irreducible loop gets heavily weighted back-edges.
define void @test9(i32 %i, i32 %x, i32 %c) {
entry:
  %tobool = icmp eq i32 %c, 0
  br i1 %tobool, label %if.end, label %midloop
; CHECK:  edge %entry -> %if.end probability is 0x30000000 / 0x80000000 = 37.50%
; CHECK:  edge %entry -> %midloop probability is 0x50000000 / 0x80000000 = 62.50%

if.end:
  br label %for.cond
; CHECK:  edge %if.end -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.cond:
  %i.addr.0 = phi i32 [ %inc, %for.inc ], [ 0, %if.end ]
  %cmp = icmp slt i32 %i.addr.0, %x
  br i1 %cmp, label %midloop, label %end
; CHECK:  edge %for.cond -> %midloop probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK:  edge %for.cond -> %end probability is 0x04000000 / 0x80000000 = 3.12%

midloop:
  %i.addr.1 = phi i32 [ %i, %entry ], [ %i.addr.0, %for.cond ]
  %call1 = call i32 @g5()
  %tobool2 = icmp eq i32 %call1, 0
  br i1 %tobool2, label %for.inc, label %end
; CHECK:  edge %midloop -> %for.inc probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK:  edge %midloop -> %end probability is 0x04000000 / 0x80000000 = 3.12%

for.inc:
  %inc = add nsw i32 %i.addr.1, 1
  br label %for.cond
; CHECK:  edge %for.inc -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

end:
  ret void
}

; Check that the for.body -> if.then edge is considered unlikely due to making
; the if-condition false for the next iteration of the loop.
define i32 @test10(i32 %n, ptr %p) {
entry:
  br label %for.cond
; CHECK: edge %entry -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.cond:
  %count.0 = phi i32 [ 0, %entry ], [ %count.1, %for.inc ]
  %sum.0 = phi i32 [ 0, %entry ], [ %sum.1, %for.inc ]
  %i.0 = phi i32 [ 0, %entry ], [ %inc3, %for.inc ]
  %cmp = icmp slt i32 %i.0, %n
  br i1 %cmp, label %for.body, label %for.cond.cleanup
; CHECK: edge %for.cond -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %for.cond -> %for.cond.cleanup probability is 0x04000000 / 0x80000000 = 3.12%

for.cond.cleanup:
  ret i32 %sum.0

for.body:
  %arrayidx = getelementptr inbounds i32, ptr %p, i32 %i.0
  %0 = load i32, ptr %arrayidx, align 4
  %add = add nsw i32 %sum.0, %0
  %inc = add nsw i32 %count.0, 1
  %cmp1 = icmp sgt i32 %count.0, 6
  br i1 %cmp1, label %if.then, label %for.inc
; CHECK: edge %for.body -> %if.then probability is 0x2aaaa8e4 / 0x80000000 = 33.33%
; CHECK: edge %for.body -> %for.inc probability is 0x5555571c / 0x80000000 = 66.67%
if.then:
  store i32 %add, ptr %arrayidx, align 4
  br label %for.inc
; CHECK: edge %if.then -> %for.inc probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.inc:
  %count.1 = phi i32 [ 0, %if.then ], [ %inc, %for.body ]
  %sum.1 = phi i32 [ 0, %if.then ], [ %add, %for.body ]
  %inc3 = add nsw i32 %i.0, 1
  br label %for.cond
; CHECK: edge %for.inc -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
}

; Each successor to for.body makes itself not be taken in the next iteration, so
; both should be equally likely
define i32 @test11(i32 %n, ptr %p) {
entry:
  br label %for.cond
; CHECK: edge %entry -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.cond:
  %flip.0 = phi i32 [ 0, %entry ], [ %flip.1, %for.inc ]
  %sum.0 = phi i32 [ 0, %entry ], [ %sum.1, %for.inc ]
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]
  %cmp = icmp slt i32 %i.0, %n
  br i1 %cmp, label %for.body, label %for.cond.cleanup
; CHECK: edge %for.cond -> %for.body probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %for.cond -> %for.cond.cleanup probability is 0x04000000 / 0x80000000 = 3.12%

for.cond.cleanup:
  ret i32 %sum.0

for.body:
  %tobool = icmp eq i32 %flip.0, 0
  %arrayidx1 = getelementptr inbounds i32, ptr %p, i32 %i.0
  %0 = load i32, ptr %arrayidx1, align 4
  br i1 %tobool, label %if.else, label %if.then
; CHECK: edge %for.body -> %if.else probability is 0x40000000 / 0x80000000 = 50.00%
; CHECK: edge %for.body -> %if.then probability is 0x40000000 / 0x80000000 = 50.00%

if.then:
  %add = add nsw i32 %0, %sum.0
  store i32 %add, ptr %arrayidx1, align 4
  br label %for.inc
; CHECK: edge %if.then -> %for.inc probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

if.else:
  %add2 = add nsw i32 %sum.0, %0
  br label %for.inc
; CHECK: edge %if.else -> %for.inc probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

for.inc:
  %flip.1 = phi i32 [ 0, %if.then ], [ 1, %if.else ]
  %sum.1 = phi i32 [ %sum.0, %if.then ], [ %add2, %if.else ]
  %inc = add nsw i32 %i.0, 1
  br label %for.cond
; CHECK: edge %for.inc -> %for.cond probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
}

; The loop heuristic should not overwrite the invoke heuristic. The unwind destination
; of an invoke should be considered VERY rare even in a loop.
define void @test12(i32 %a) personality i8 0 {
entry:
  br label %loop
; CHECK: edge %entry -> %loop probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

loop:
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %invoke.cont ]
  invoke i32 @InvokeCall()
          to label %invoke.cont unwind label %lpad
; CHECK: edge %loop -> %invoke.cont probability is 0x7ffff800 / 0x80000000 = 100.00% [HOT edge]
; CHECK: edge %loop -> %lpad probability is 0x00000800 / 0x80000000 = 0.00%

invoke.cont:
  %inc = add nsw i32 %i.0, 1
  %cmp = icmp slt i32 %inc, %a
  br i1 %cmp, label %loop, label %exit
; CHECK: edge %invoke.cont -> %loop probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %invoke.cont -> %exit probability is 0x04000000 / 0x80000000 = 3.12%

lpad:
  %ll = landingpad { ptr, i32 }
          cleanup
  br label %exit

exit:
  ret void
}

declare i32 @InvokeCall()
declare void @cold() cold

; If loop has single exit and it leads to 'cold' block then edge leading to loop enter
; should be considered 'cold' as well.
define void @test13() {
; CHECK: edge %entry -> %loop probability is 0x078780e3 / 0x80000000 = 5.88%
; CHECK: edge %entry -> %exit probability is 0x78787f1d / 0x80000000 = 94.12% [HOT edge]
; CHECK: edge %loop -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]
; CHECK: edge %loop -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%
; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

entry:
  br i1 undef, label %loop, label %exit

loop:
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %loop ]
  %inc = add nsw i32 %i.0, 1
  br i1 undef, label %loop, label %cold

cold:
  call void @cold()
  br label %exit

exit:
  ret void
}

; This is the same case as test13 but with additional loop 'preheader' block.
define void @test14() {
; CHECK: edge %entry -> %preheader probability is 0x078780e3 / 0x80000000 = 5.88%
; CHECK: edge %entry -> %exit probability is 0x78787f1d / 0x80000000 = 94.12% [HOT edge]
; CHECK: edge %preheader -> %loop probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
; CHECK: edge %loop -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]
; CHECK: edge %loop -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%
; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

entry:
  br i1 undef, label %preheader, label %exit

preheader:
  br label %loop

loop:
  %i.0 = phi i32 [ 0, %preheader ], [ %inc, %loop ]
  %inc = add nsw i32 %i.0, 1
  br i1 undef, label %loop, label %cold

cold:
  call void @cold()
  br label %exit

exit:
  ret void
}

; If loop has multiple low probability exits then edge leading to loop enter
; should be considered low probable as well.
define void @test15() {
; CHECK: edge %entry -> %loop probability is 0x078780e3 / 0x80000000 = 5.88%
; CHECK: edge %entry -> %exit probability is 0x78787f1d / 0x80000000 = 94.12% [HOT edge]
; CHECK: edge %loop -> %cont probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
; CHECK: edge %loop -> %unreached probability is 0x00000000 / 0x80000000 = 0.00%
; CHECK: edge %cont -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]
; CHECK: edge %cont -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%
; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

entry:
  br i1 undef, label %loop, label %exit

loop:
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %cont ]
  %inc = add nsw i32 %i.0, 1
  br i1 undef, label %cont, label %unreached

cont:
  br i1 undef, label %loop, label %cold

unreached:
  unreachable


cold:
  call void @cold()
  br label %exit

exit:
  ret void
}

; This is the same case as test15 but with additional loop 'preheader' block.
define void @test16() {
; CHECK: edge %entry -> %preheader probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
; CHECK: edge %preheader -> %loop probability is 0x078780e3 / 0x80000000 = 5.88%
; CHECK: edge %preheader -> %exit probability is 0x78787f1d / 0x80000000 = 94.12% [HOT edge]
; CHECK: edge %loop -> %cont probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
; CHECK: edge %loop -> %unreached probability is 0x00000000 / 0x80000000 = 0.00%
; CHECK: edge %cont -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]
; CHECK: edge %cont -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%
; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

entry:
  br label %preheader

preheader:
  br i1 undef, label %loop, label %exit

loop:
  %i.0 = phi i32 [ 0, %preheader ], [ %inc, %cont ]
  %inc = add nsw i32 %i.0, 1
  br i1 undef, label %cont, label %unreached

cont:
  br i1 undef, label %loop, label %cold

unreached:
  unreachable


cold:
  call void @cold()
  br label %exit

exit:
  ret void
}

declare void @abort() noreturn

; Check that 'preheader' has 50/50 probability since there is one 'normal' exit.
; Check that exit to 'cold' and 'noreturn' has lower probability than 'normal' exit.
define void @test17() {
; CHECK: edge %entry -> %preheader probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
; CHECK: edge %preheader -> %loop probability is 0x40000000 / 0x80000000 = 50.00%
; CHECK: edge %preheader -> %exit probability is 0x40000000 / 0x80000000 = 50.00%
; CHECK: edge %loop -> %cont probability is 0x7ffff800 / 0x80000000 = 100.00% [HOT edge]
; CHECK: edge %loop -> %noreturn probability is 0x00000800 / 0x80000000 = 0.00%
; CHECK: edge %cont -> %cont2 probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]
; CHECK: edge %cont -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%
; CHECK: edge %cont2 -> %loop probability is 0x7c000000 / 0x80000000 = 96.88% [HOT edge]
; CHECK: edge %cont2 -> %exit probability is 0x04000000 / 0x80000000 = 3.12%
; CHECK: edge %cold -> %exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
entry:
  br label %preheader

preheader:
  br i1 undef, label %loop, label %exit

loop:
  %i.0 = phi i32 [ 0, %preheader ], [ %inc, %cont2 ]
  %inc = add nsw i32 %i.0, 1
  br i1 undef, label %cont, label %noreturn

cont:
  br i1 undef, label %cont2, label %cold

cont2:
  br i1 undef, label %loop, label %exit

noreturn:
  call void @abort()
  unreachable

cold:
  call void @cold()
  br label %exit

exit:
  ret void
}


; This is case with two loops where one nested into another. Nested loop has
; low probable exit what encreases robability to take exit in the top level loop.
define void @test18() {
; CHECK: edge %entry -> %top.loop probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]
; CHECK: edge %top.loop -> %loop probability is 0x546cd4b7 / 0x80000000 = 65.96%
; CHECK: edge %top.loop -> %exit probability is 0x2b932b49 / 0x80000000 = 34.04%
; CHECK: edge %loop -> %loop probability is 0x7fbe1203 / 0x80000000 = 99.80% [HOT edge]
; CHECK: edge %loop -> %cold probability is 0x0041edfd / 0x80000000 = 0.20%
; CHECK: edge %cold -> %top.loop probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge]

entry:
 br label %top.loop 

top.loop:
  %j.0 = phi i32 [ 0, %entry ], [ %j.inc, %cold ]
  br i1 undef, label %loop, label %exit

loop:
  %i.0 = phi i32 [ %j.0, %top.loop ], [ %inc, %loop ]
  %inc = add nsw i32 %i.0, 1
  br i1 undef, label %loop, label %cold

cold:
  call void @cold()
  %j.inc = add nsw i32 %j.0, 1
  br label %top.loop

exit:
  ret void
}