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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 = 1024
entry:
br label %body
; Loop backedges are weighted and thus their bodies have a greater frequency.
; CHECK: body = 31744
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 = 1024
exit:
ret i32 %sum
}
define i32 @test2(i32 %i, i32 %a, i32 %b) {
; CHECK: Printing analysis {{.*}} for function 'test2'
; CHECK: entry = 1024
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 = 963
then:
br label %exit
; CHECK: else = 60
else:
br label %exit
; FIXME: It may be a bug that we don't sum back to 1024.
; CHECK: exit = 1023
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 = 1024
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 = 51
case_a:
br label %exit
; CHECK: case_b = 51
case_b:
br label %exit
; The 'case_c' branch is predicted more likely via branch weight metadata.
; CHECK: case_c = 819
case_c:
br label %exit
; CHECK: case_d = 51
case_d:
br label %exit
; CHECK: case_e = 51
case_e:
br label %exit
; FIXME: It may be a bug that we don't sum back to 1024.
; CHECK: exit = 1023
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}
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