; RUN: opt -gvn -S -o - %s | FileCheck %s ; RUN: opt -passes=gvn -S -o - %s | FileCheck %s %struct.sk_buff = type opaque @l2tp_recv_dequeue_session = external dso_local local_unnamed_addr global i32, align 4 @l2tp_recv_dequeue_skb = external dso_local local_unnamed_addr global %struct.sk_buff*, align 8 @l2tp_recv_dequeue_session_2 = external dso_local local_unnamed_addr global i32, align 4 @l2tp_recv_dequeue_session_0 = external dso_local local_unnamed_addr global i32, align 4 declare void @llvm.assume(i1 noundef) define dso_local void @l2tp_recv_dequeue() local_unnamed_addr { entry: %0 = load i32, i32* @l2tp_recv_dequeue_session, align 4 %conv = sext i32 %0 to i64 %1 = inttoptr i64 %conv to %struct.sk_buff* %2 = load i32, i32* @l2tp_recv_dequeue_session_2, align 4 %tobool.not = icmp eq i32 %2, 0 br label %for.cond for.cond: ; preds = %if.end, %entry %storemerge = phi %struct.sk_buff* [ %1, %entry ], [ null, %if.end ] store %struct.sk_buff* %storemerge, %struct.sk_buff** @l2tp_recv_dequeue_skb, align 8 br i1 %tobool.not, label %if.end, label %if.then if.then: ; preds = %for.cond %ns = bitcast %struct.sk_buff* %storemerge to i32* %3 = load i32, i32* %ns, align 4 store i32 %3, i32* @l2tp_recv_dequeue_session_0, align 4 ; Splitting the critical edge from if.then to if.end will fail, but should not ; cause an infinite loop in GVN. If we can one day split edges of callbr ; indirect targets, great! ; CHECK: callbr void asm sideeffect "", "X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@l2tp_recv_dequeue, %if.end)) ; CHECK-NEXT: to label %asm.fallthrough.i [label %if.end] callbr void asm sideeffect "", "X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@l2tp_recv_dequeue, %if.end)) to label %asm.fallthrough.i [label %if.end] asm.fallthrough.i: ; preds = %if.then br label %if.end if.end: ; preds = %asm.fallthrough.i, %if.then, %for.cond %ns1 = bitcast %struct.sk_buff* %storemerge to i32* %4 = load i32, i32* %ns1, align 4 %tobool2.not = icmp eq i32 %4, 0 tail call void @llvm.assume(i1 %tobool2.not) br label %for.cond }