; 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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %c, i64 1
%arrayidx9 = getelementptr inbounds i32, i32* %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, i32* %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, i32* %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, i32* %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, i32* %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, i32* %p, i32 %i.0
%0 = load i32, i32* %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, i32* %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, i32* %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, i32* %p, i32 %i.0
%0 = load i32, i32* %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, i32* %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 { i8*, 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
}