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; 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
}
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