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; RUN: opt < %s -analyze -block-freq | FileCheck %s
define i32 @test1(i32 %i, i32* %a) {
; CHECK: Printing analysis {{.*}} for function 'test1'
; CHECK: entry = 1.0
entry:
br label %body
; Loop backedges are weighted and thus their bodies have a greater frequency.
; CHECK: body = 32.0
body:
%iv = phi i32 [ 0, %entry ], [ %next, %body ]
%base = phi i32 [ 0, %entry ], [ %sum, %body ]
%arrayidx = getelementptr inbounds i32* %a, i32 %iv
%0 = load i32* %arrayidx
%sum = add nsw i32 %0, %base
%next = add i32 %iv, 1
%exitcond = icmp eq i32 %next, %i
br i1 %exitcond, label %exit, label %body
; CHECK: exit = 1.0
exit:
ret i32 %sum
}
define i32 @test2(i32 %i, i32 %a, i32 %b) {
; CHECK: Printing analysis {{.*}} for function 'test2'
; CHECK: entry = 1.0
entry:
%cond = icmp ult i32 %i, 42
br i1 %cond, label %then, label %else, !prof !0
; The 'then' branch is predicted more likely via branch weight metadata.
; CHECK: then = 0.94116
then:
br label %exit
; CHECK: else = 0.05877
else:
br label %exit
; FIXME: It may be a bug that we don't sum back to 1.0.
; CHECK: exit = 0.99993
exit:
%result = phi i32 [ %a, %then ], [ %b, %else ]
ret i32 %result
}
!0 = metadata !{metadata !"branch_weights", i32 64, i32 4}
define i32 @test3(i32 %i, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) {
; CHECK: Printing analysis {{.*}} for function 'test3'
; CHECK: entry = 1.0
entry:
switch i32 %i, label %case_a [ i32 1, label %case_b
i32 2, label %case_c
i32 3, label %case_d
i32 4, label %case_e ], !prof !1
; CHECK: case_a = 0.04998
case_a:
br label %exit
; CHECK: case_b = 0.04998
case_b:
br label %exit
; The 'case_c' branch is predicted more likely via branch weight metadata.
; CHECK: case_c = 0.79998
case_c:
br label %exit
; CHECK: case_d = 0.04998
case_d:
br label %exit
; CHECK: case_e = 0.04998
case_e:
br label %exit
; FIXME: It may be a bug that we don't sum back to 1.0.
; CHECK: exit = 0.99993
exit:
%result = phi i32 [ %a, %case_a ],
[ %b, %case_b ],
[ %c, %case_c ],
[ %d, %case_d ],
[ %e, %case_e ]
ret i32 %result
}
!1 = metadata !{metadata !"branch_weights", i32 4, i32 4, i32 64, i32 4, i32 4}
; CHECK: Printing analysis {{.*}} for function 'nested_loops'
; CHECK: entry = 1.0
; This test doesn't seem to be assigning sensible frequencies to nested loops.
define void @nested_loops(i32 %a) {
entry:
br label %for.cond1.preheader
for.cond1.preheader:
%x.024 = phi i32 [ 0, %entry ], [ %inc12, %for.inc11 ]
br label %for.cond4.preheader
for.cond4.preheader:
%y.023 = phi i32 [ 0, %for.cond1.preheader ], [ %inc9, %for.inc8 ]
%add = add i32 %y.023, %x.024
br label %for.body6
for.body6:
%z.022 = phi i32 [ 0, %for.cond4.preheader ], [ %inc, %for.body6 ]
%add7 = add i32 %add, %z.022
tail call void @g(i32 %add7) #2
%inc = add i32 %z.022, 1
%cmp5 = icmp ugt i32 %inc, %a
br i1 %cmp5, label %for.inc8, label %for.body6, !prof !2
for.inc8:
%inc9 = add i32 %y.023, 1
%cmp2 = icmp ugt i32 %inc9, %a
br i1 %cmp2, label %for.inc11, label %for.cond4.preheader, !prof !2
for.inc11:
%inc12 = add i32 %x.024, 1
%cmp = icmp ugt i32 %inc12, %a
br i1 %cmp, label %for.end13, label %for.cond1.preheader, !prof !2
for.end13:
ret void
}
declare void @g(i32) #1
!2 = metadata !{metadata !"branch_weights", i32 1, i32 4000}
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