llvm-project/llvm/test/Transforms/JumpThreading/unreachable-loops.ll

64 lines
1.8 KiB
LLVM

; RUN: opt -jump-threading -S < %s | FileCheck %s
; RUN: opt -passes=jump-threading -S < %s | FileCheck %s
; Check the unreachable loop won't cause infinite loop
; in jump-threading when it tries to update the predecessors'
; profile metadata from a phi node.
define void @unreachable_single_bb_loop() {
; CHECK-LABEL: @unreachable_single_bb_loop()
bb:
%tmp = call i32 @a()
%tmp1 = icmp eq i32 %tmp, 1
br i1 %tmp1, label %bb5, label %bb8
; unreachable single bb loop.
bb2: ; preds = %bb2
%tmp4 = icmp ne i32 %tmp, 1
switch i1 %tmp4, label %bb2 [
i1 0, label %bb5
i1 1, label %bb8
]
bb5: ; preds = %bb2, %bb
%tmp6 = phi i1 [ %tmp1, %bb ], [ false, %bb2 ]
br i1 %tmp6, label %bb8, label %bb7, !prof !0
bb7: ; preds = %bb5
br label %bb8
bb8: ; preds = %bb8, %bb7, %bb5, %bb2
ret void
}
define void @unreachable_multi_bbs_loop() {
; CHECK-LABEL: @unreachable_multi_bbs_loop()
bb:
%tmp = call i32 @a()
%tmp1 = icmp eq i32 %tmp, 1
br i1 %tmp1, label %bb5, label %bb8
; unreachable two bbs loop.
bb3: ; preds = %bb2
br label %bb2
bb2: ; preds = %bb3
%tmp4 = icmp ne i32 %tmp, 1
switch i1 %tmp4, label %bb3 [
i1 0, label %bb5
i1 1, label %bb8
]
bb5: ; preds = %bb2, %bb
%tmp6 = phi i1 [ %tmp1, %bb ], [ false, %bb2 ]
br i1 %tmp6, label %bb8, label %bb7, !prof !0
bb7: ; preds = %bb5
br label %bb8
bb8: ; preds = %bb8, %bb7, %bb5, %bb2
ret void
}
declare i32 @a()
!0 = !{!"branch_weights", i32 2146410443, i32 1073205}