1; RUN: opt -passes=gvn -S -o - %s | FileCheck %s 2 3%struct.sk_buff = type opaque 4 5@l2tp_recv_dequeue_session = external dso_local local_unnamed_addr global i32, align 4 6@l2tp_recv_dequeue_skb = external dso_local local_unnamed_addr global ptr, align 8 7@l2tp_recv_dequeue_session_2 = external dso_local local_unnamed_addr global i32, align 4 8@l2tp_recv_dequeue_session_0 = external dso_local local_unnamed_addr global i32, align 4 9 10declare void @llvm.assume(i1 noundef) 11 12define dso_local void @l2tp_recv_dequeue() local_unnamed_addr { 13entry: 14 %0 = load i32, ptr @l2tp_recv_dequeue_session, align 4 15 %conv = sext i32 %0 to i64 16 %1 = inttoptr i64 %conv to ptr 17 %2 = load i32, ptr @l2tp_recv_dequeue_session_2, align 4 18 %tobool.not = icmp eq i32 %2, 0 19 br label %for.cond 20 21for.cond: ; preds = %if.end, %entry 22 %storemerge = phi ptr [ %1, %entry ], [ null, %if.end ] 23 store ptr %storemerge, ptr @l2tp_recv_dequeue_skb, align 8 24 br i1 %tobool.not, label %if.end, label %if.then 25 26if.then: ; preds = %for.cond 27 %3 = load i32, ptr %storemerge, align 4 28 store i32 %3, ptr @l2tp_recv_dequeue_session_0, align 4 29; Splitting the critical edge from if.then to if.end will fail, but should not 30; cause an infinite loop in GVN. If we can one day split edges of callbr 31; indirect targets, great! 32; CHECK: callbr void asm sideeffect "", "!i,~{dirflag},~{fpsr},~{flags}"() 33; CHECK-NEXT: to label %asm.fallthrough.i [label %if.end] 34 callbr void asm sideeffect "", "!i,~{dirflag},~{fpsr},~{flags}"() 35 to label %asm.fallthrough.i [label %if.end] 36 37asm.fallthrough.i: ; preds = %if.then 38 br label %if.end 39 40if.end: ; preds = %asm.fallthrough.i, %if.then, %for.cond 41 %4 = load i32, ptr %storemerge, align 4 42 %tobool2.not = icmp eq i32 %4, 0 43 tail call void @llvm.assume(i1 %tobool2.not) 44 br label %for.cond 45} 46 47