src/share/vm/opto/library_call.cpp

rev 12619 : 8174164: SafePointNode::_replaced_nodes breaks with irreducible loops
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rev 12620 : 8174164: SafePointNode::_replaced_nodes breaks with irreducible loops
Reviewed-by:
rev 12697 : 8176506: C2: loop unswitching and unsafe accesses cause crash
Reviewed-by:
rev 12698 : 8176513: Poor code quality for ByteBuffers
Reviewed-by:
rev 12699 : 8176513: Poor code quality for ByteBuffers
Summary: relax conditions that causes MemBarCPUOrder membars to be added around unsafe accesses
Reviewed-by:

*** 2373,2383 ****
    // the alias analysis of the rest of the graph, either Compile::can_alias
    // or Compile::must_alias will throw a diagnostic assert.)
    bool need_mem_bar;
    switch (kind) {
        case Relaxed:
!           need_mem_bar = mismatched || can_access_non_heap;
            break;
        case Opaque:
            // Opaque uses CPUOrder membars for protection against code movement.
        case Acquire:
        case Release:
--- 2373,2383 ----
    // the alias analysis of the rest of the graph, either Compile::can_alias
    // or Compile::must_alias will throw a diagnostic assert.)
    bool need_mem_bar;
    switch (kind) {
        case Relaxed:
!           need_mem_bar = mismatched & !adr_type->isa_aryptr();
            break;
        case Opaque:
            // Opaque uses CPUOrder membars for protection against code movement.
        case Acquire:
        case Release: