; RUN: opt -S -passes=gvn-hoist < %s | FileCheck %s ; Checking gvn-hoist in case of infinite loops and irreducible control flow. ; Check that bitcast is not hoisted beacuse down safety is not guaranteed. ; CHECK-LABEL: @bazv1 ; CHECK: if.then.i: ; CHECK: bitcast ; CHECK-NEXT: load ; CHECK: if.then4.i: ; CHECK: bitcast ; CHECK-NEXT: load %class.bar = type { ptr, ptr } %class.base = type { ptr } ; Function Attrs: noreturn nounwind uwtable define void @bazv1() local_unnamed_addr { entry: %agg.tmp = alloca %class.bar, align 8 %x.sroa.2.0..sroa_idx2 = getelementptr inbounds %class.bar, ptr %agg.tmp, i64 0, i32 1 store ptr null, ptr %x.sroa.2.0..sroa_idx2, align 8 call void @_Z3foo3bar(ptr nonnull %agg.tmp) %0 = load ptr, ptr %x.sroa.2.0..sroa_idx2, align 8 %1 = bitcast ptr %agg.tmp to ptr %cmp.i = icmp eq ptr %0, %1 br i1 %cmp.i, label %if.then.i, label %if.else.i if.then.i: ; preds = %entry %2 = bitcast ptr %0 to ptr %vtable.i = load ptr, ptr %2, align 8 %vfn.i = getelementptr inbounds ptr, ptr %vtable.i, i64 2 %3 = load ptr, ptr %vfn.i, align 8 call void %3(ptr %0) br label %while.cond.preheader if.else.i: ; preds = %entry %tobool.i = icmp eq ptr %0, null br i1 %tobool.i, label %while.cond.preheader, label %if.then4.i if.then4.i: ; preds = %if.else.i %4 = bitcast ptr %0 to ptr %vtable6.i = load ptr, ptr %4, align 8 %vfn7.i = getelementptr inbounds ptr, ptr %vtable6.i, i64 3 %5 = load ptr, ptr %vfn7.i, align 8 call void %5(ptr nonnull %0) br label %while.cond.preheader while.cond.preheader: ; preds = %if.then.i, %if.else.i, %if.then4.i br label %while.cond while.cond: ; preds = %while.cond.preheader, %while.cond %call = call i32 @sleep(i32 10) br label %while.cond } declare void @_Z3foo3bar(ptr) local_unnamed_addr declare i32 @sleep(i32) local_unnamed_addr ; Check that the load is hoisted even if it is inside an irreducible control flow ; because the load is anticipable on all paths. ; CHECK-LABEL: @bazv ; CHECK: bb2: ; CHECK-NOT: load ; CHECK-NOT: bitcast define void @bazv() { entry: %agg.tmp = alloca %class.bar, align 8 %x= getelementptr inbounds %class.bar, ptr %agg.tmp, i64 0, i32 1 %0 = load ptr, ptr %x, align 8 %1 = bitcast ptr %agg.tmp to ptr %cmp.i = icmp eq ptr %0, %1 br i1 %cmp.i, label %bb1, label %bb4 bb1: %b1 = bitcast ptr %0 to ptr %i = load ptr, ptr %b1, align 8 %vfn.i = getelementptr inbounds ptr, ptr %i, i64 2 %cmp.j = icmp eq ptr %0, %1 br i1 %cmp.j, label %bb2, label %bb3 bb2: %l1 = load ptr, ptr %vfn.i, align 8 br label %bb3 bb3: %l2 = load ptr, ptr %vfn.i, align 8 br label %bb2 bb4: %b2 = bitcast ptr %0 to ptr ret void }