; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -asm-verbose=false | FileCheck %s
; These tests check for loop branching structure, and that the loop align
; directive is placed in the expected place.
; CodeGen should insert a branch into the middle of the loop in
; order to avoid a branch within the loop.
; CHECK-LABEL: simple:
; CHECK: align
; CHECK-NEXT: .LBB0_1:
; CHECK-NEXT: callq loop_header
; CHECK: js .LBB0_3
; CHECK-NEXT: callq loop_latch
; CHECK-NEXT: jmp .LBB0_1
; CHECK-NEXT: .LBB0_3:
; CHECK-NEXT: callq exit
define void @simple() nounwind {
entry:
br label %loop
loop:
call void @loop_header()
%t0 = tail call i32 @get()
%t1 = icmp slt i32 %t0, 0
br i1 %t1, label %done, label %bb
bb:
call void @loop_latch()
br label %loop
done:
call void @exit()
ret void
}
; CodeGen should move block_a to the top of the loop so that it
; falls through into the loop, avoiding a branch within the loop.
; CHECK-LABEL: slightly_more_involved:
; CHECK: jmp .LBB1_1
; CHECK-NEXT: align
; CHECK-NEXT: .LBB1_4:
; CHECK-NEXT: callq bar99
; CHECK-NEXT: .LBB1_1:
; CHECK-NEXT: callq body
define void @slightly_more_involved() nounwind {
entry:
br label %loop
loop:
call void @body()
%t0 = call i32 @get()
%t1 = icmp slt i32 %t0, 2
br i1 %t1, label %block_a, label %bb
bb:
%t2 = call i32 @get()
%t3 = icmp slt i32 %t2, 99
br i1 %t3, label %exit, label %loop
block_a:
call void @bar99()
br label %loop
exit:
call void @exit()
ret void
}
; Same as slightly_more_involved, but block_a is now a CFG diamond with
; fallthrough edges which should be preserved.
; "callq block_a_merge_func" is tail duped.
; CHECK-LABEL: yet_more_involved:
; CHECK: jmp .LBB2_1
; CHECK-NEXT: align
; CHECK: .LBB2_1:
; CHECK-NEXT: callq body
; CHECK-NEXT: callq get
; CHECK-NEXT: cmpl $2, %eax
; CHECK-NEXT: jge .LBB2_2
; CHECK-NEXT: callq bar99
; CHECK-NEXT: callq get
; CHECK-NEXT: cmpl $2999, %eax
; CHECK-NEXT: jg .LBB2_6
; CHECK-NEXT: callq block_a_true_func
; CHECK-NEXT: callq block_a_merge_func
; CHECK-NEXT: jmp .LBB2_1
; CHECK-NEXT: align
; CHECK-NEXT: .LBB2_6:
; CHECK-NEXT: callq block_a_false_func
; CHECK-NEXT: callq block_a_merge_func
; CHECK-NEXT: jmp .LBB2_1
define void @yet_more_involved() nounwind {
entry:
br label %loop
loop:
call void @body()
%t0 = call i32 @get()
%t1 = icmp slt i32 %t0, 2
br i1 %t1, label %block_a, label %bb
bb:
%t2 = call i32 @get()
%t3 = icmp slt i32 %t2, 99
br i1 %t3, label %exit, label %loop
block_a:
call void @bar99()
%z0 = call i32 @get()
%z1 = icmp slt i32 %z0, 3000
br i1 %z1, label %block_a_true, label %block_a_false
block_a_true:
call void @block_a_true_func()
br label %block_a_merge
block_a_false:
call void @block_a_false_func()
br label %block_a_merge
block_a_merge:
call void @block_a_merge_func()
br label %loop
exit:
call void @exit()
ret void
}
; CodeGen should move the CFG islands that are part of the loop but don't
; conveniently fit anywhere so that they are at least contiguous with the
; loop.
; CHECK-LABEL: cfg_islands:
; CHECK: jmp .LBB3_1
; CHECK-NEXT: align
; CHECK-NEXT: .LBB3_7:
; CHECK-NEXT: callq bar100
; CHECK-NEXT: .LBB3_1:
; CHECK-NEXT: callq loop_header
; CHECK: jl .LBB3_7
; CHECK: jge .LBB3_3
; CHECK-NEXT: callq bar101
; CHECK-NEXT: jmp .LBB3_1
; CHECK-NEXT: align
; CHECK-NEXT: .LBB3_3:
; CHECK: jge .LBB3_4
; CHECK-NEXT: callq bar102
; CHECK-NEXT: jmp .LBB3_1
; CHECK-NEXT: .LBB3_4:
; CHECK: jl .LBB3_6
; CHECK-NEXT: callq loop_latch
; CHECK-NEXT: jmp .LBB3_1
; CHECK-NEXT: .LBB3_6:
define void @cfg_islands() nounwind {
entry:
br label %loop
loop:
call void @loop_header()
%t0 = call i32 @get()
%t1 = icmp slt i32 %t0, 100
br i1 %t1, label %block100, label %bb
bb:
%t2 = call i32 @get()
%t3 = icmp slt i32 %t2, 101
br i1 %t3, label %block101, label %bb1
bb1:
%t4 = call i32 @get()
%t5 = icmp slt i32 %t4, 102
br i1 %t5, label %block102, label %bb2
bb2:
%t6 = call i32 @get()
%t7 = icmp slt i32 %t6, 103
br i1 %t7, label %exit, label %bb3
bb3:
call void @loop_latch()
br label %loop
exit:
call void @exit()
ret void
block100:
call void @bar100()
br label %loop
block101:
call void @bar101()
br label %loop
block102:
call void @bar102()
br label %loop
}
; CHECK-LABEL: check_minsize:
; CHECK-NOT: align
; CHECK: .LBB4_1:
; CHECK-NEXT: callq loop_header
; CHECK: callq loop_latch
; CHECK: .LBB4_3:
; CHECK: callq exit
define void @check_minsize() minsize nounwind {
entry:
br label %loop
loop:
call void @loop_header()
%t0 = tail call i32 @get()
%t1 = icmp slt i32 %t0, 0
br i1 %t1, label %done, label %bb
bb:
call void @loop_latch()
br label %loop
done:
call void @exit()
ret void
}
; This is exactly the same function as slightly_more_involved.
; The difference is that when optimising for size, we do not want
; to see this reordering.
; CHECK-LABEL: slightly_more_involved_2:
; CHECK-NOT: jmp .LBB5_1
; CHECK: .LBB5_1:
; CHECK-NEXT: callq body
define void @slightly_more_involved_2() #0 {
entry:
br label %loop
loop:
call void @body()
%t0 = call i32 @get()
%t1 = icmp slt i32 %t0, 2
br i1 %t1, label %block_a, label %bb
bb:
%t2 = call i32 @get()
%t3 = icmp slt i32 %t2, 99
br i1 %t3, label %exit, label %loop
block_a:
call void @bar99()
br label %loop
exit:
call void @exit()
ret void
}
attributes #0 = { minsize norecurse nounwind optsize readnone uwtable }
; CHECK-LABEL: slightly_more_involved_2_pgso:
; CHECK-NOT: jmp .LBB6_1
; CHECK: .LBB6_1:
; CHECK-NEXT: callq body
define void @slightly_more_involved_2_pgso() norecurse nounwind readnone uwtable !prof !14 {
entry:
br label %loop
loop:
call void @body()
%t0 = call i32 @get()
%t1 = icmp slt i32 %t0, 2
br i1 %t1, label %block_a, label %bb
bb:
%t2 = call i32 @get()
%t3 = icmp slt i32 %t2, 99
br i1 %t3, label %exit, label %loop
block_a:
call void @bar99()
br label %loop
exit:
call void @exit()
ret void
}
declare void @bar99() nounwind
declare void @bar100() nounwind
declare void @bar101() nounwind
declare void @bar102() nounwind
declare void @body() nounwind
declare void @exit() nounwind
declare void @loop_header() nounwind
declare void @loop_latch() nounwind
declare i32 @get() nounwind
declare void @block_a_true_func() nounwind
declare void @block_a_false_func() nounwind
declare void @block_a_merge_func() nounwind
!llvm.module.flags = !{!0}
!0 = !{i32 1, !"ProfileSummary", !1}
!1 = !{!2, !3, !4, !5, !6, !7, !8, !9}
!2 = !{!"ProfileFormat", !"InstrProf"}
!3 = !{!"TotalCount", i64 10000}
!4 = !{!"MaxCount", i64 10}
!5 = !{!"MaxInternalCount", i64 1}
!6 = !{!"MaxFunctionCount", i64 1000}
!7 = !{!"NumCounts", i64 3}
!8 = !{!"NumFunctions", i64 3}
!9 = !{!"DetailedSummary", !10}
!10 = !{!11, !12, !13}
!11 = !{i32 10000, i64 100, i32 1}
!12 = !{i32 999000, i64 100, i32 1}
!13 = !{i32 999999, i64 1, i32 2}
!14 = !{!"function_entry_count", i64 0}
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