RFR: Bulk backports sh/jdk11 -> sh/jdk8u

[Aleksey Shipilev]

On 3/16/19 11:36 AM, Roman Kennke wrote:
>> *) Asserts seem excessive here, already under UseShenandoahGC branch:
>>
>> 2349 #if INCLUDE_ALL_GCS
>> 2350   if (UseShenandoahGC) {
>> 2351     if (mode == LoopOptsShenandoahExpand) {
>> 2352       assert(UseShenandoahGC, "only for shenandoah");
>> 2353       ShenandoahWriteBarrierNode::pin_and_expand(this);
>> 2354     } else if (mode == LoopOptsShenandoahPostExpand) {
>> 2355       assert(UseShenandoahGC, "only for shenandoah");
>> 2356       visited.Clear();
>> 2357       ShenandoahWriteBarrierNode::optimize_after_expansion(visited, nstack, worklist, this);
>> 2358     }
> 
> Newer versions don't have 'UseShenandoahGC' around the part, but should only ever executed (as
> asserted). I suggest we either remove the if (UseShenandoahGC) in 8, or add it to later versions. Or
> maybe just remove the assert in 8 and live with the difference? What do you think?

Nah, leave the assert as is. It is more important that the block contents are visually the same,
even if it is doing excessive work for debug builds.

-Aleksey