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| ; RUN: llc -mcpu=corei7 -mtriple=x86_64-linux < %s | FileCheck %s
define void @foo() !prof !1 {
; Test if a cold block in a loop will be placed at the end of the function
; chain.
;
; CHECK-LABEL: foo:
; CHECK: callq b
; CHECK: callq c
; CHECK: callq e
; CHECK: callq f
; CHECK: callq d
entry:
br label %header
header:
call void @b()
%call = call zeroext i1 @a()
br i1 %call, label %if.then, label %if.else, !prof !4
if.then:
call void @c()
br label %if.end
if.else:
call void @d()
br label %if.end
if.end:
call void @e()
%call2 = call zeroext i1 @a()
br i1 %call2, label %header, label %end, !prof !5
end:
call void @f()
ret void
}
define void @nested_loop_0(i1 %flag) !prof !1 {
; Test if a block that is cold in the inner loop but not cold in the outer loop
; will merged to the outer loop chain.
;
; CHECK-LABEL: nested_loop_0:
; CHECK: callq c
; CHECK: callq d
; CHECK: callq b
; CHECK: callq e
; CHECK: callq f
entry:
br label %header
header:
call void @b()
%call4 = call zeroext i1 @a()
br i1 %call4, label %header2, label %end
header2:
call void @c()
%call = call zeroext i1 @a()
br i1 %call, label %if.then, label %if.else, !prof !2
if.then:
call void @d()
%call3 = call zeroext i1 @a()
br i1 %call3, label %header2, label %header, !prof !3
if.else:
call void @e()
br i1 %flag, label %header2, label %header, !prof !3
end:
call void @f()
ret void
}
define void @nested_loop_1() !prof !1 {
; Test if a cold block in an inner loop will be placed at the end of the
; function chain.
;
; CHECK-LABEL: nested_loop_1:
; CHECK: callq b
; CHECK: callq c
; CHECK: callq e
; CHECK: callq d
entry:
br label %header
header:
call void @b()
br label %header2
header2:
call void @c()
%call = call zeroext i1 @a()
br i1 %call, label %end, label %if.else, !prof !4
if.else:
call void @d()
%call2 = call zeroext i1 @a()
br i1 %call2, label %header2, label %header, !prof !5
end:
call void @e()
ret void
}
declare zeroext i1 @a()
declare void @b()
declare void @c()
declare void @d()
declare void @e()
declare void @f()
!1 = !{!"function_entry_count", i64 1}
!2 = !{!"branch_weights", i32 100, i32 1}
!3 = !{!"branch_weights", i32 1, i32 10}
!4 = !{!"branch_weights", i32 1000, i32 1}
!5 = !{!"branch_weights", i32 100, i32 1}
|