RFR(XS): 8015437: SPARC cbcond offset value out of range

[Morris Meyer]

Sorry - eden_allocate() is where this change is located.

void MacroAssembler::eden_allocate(
   Register obj,                        // result: pointer to object 
after successful allocation
   Register var_size_in_bytes,          // object size in bytes if 
unknown at compile time; invalid otherwise
   int      con_size_in_bytes,          // object size in bytes if   
known at compile time
   Register t1,                         // temp register
   Register t2,                         // temp register
   Label&   slow_case                   // continuation point if fast 
allocation fails
){
   // make sure arguments make sense
   assert_different_registers(obj, var_size_in_bytes, t1, t2);
   assert(0 <= con_size_in_bytes && 
Assembler::is_simm13(con_size_in_bytes), "illegal object size");
   assert((con_size_in_bytes & MinObjAlignmentInBytesMask) == 0, "object 
size is not multiple of alignment");

   if (CMSIncrementalMode || 
!Universe::heap()->supports_inline_contig_alloc()) {
     // No allocation in the shared eden.
     ba(slow_case);
     delayed()->nop();


         --mm

On 6/7/13 10:16 AM, Vladimir Kozlov wrote:
> What is eden_allocate() in MacroAssembler issue?
>
> Vladimir
>
> On 6/7/13 6:24 AM, Morris Meyer wrote:
>> I substituted instructions from the non-cbcond path of ba_short():
>>
>> // Unconditional short branch
>> void MacroAssembler::ba_short(Label& L) {
>>    if (use_cbcond(L)) {
>>      Assembler::cbcond(equal, icc, G0, G0, L);
>>      return;
>>    }
>>    br(always, false, pt, L);
>>    delayed()->nop();
>> }
>>
>> Should w file a follow-on issue to address ba_short)() and 
>> eden_allocate() in MacroAssembler - or should we change both
>> and re-run the JPRT job?
>>
>>          --mm
>>
>>
>> On 6/7/13 7:59 AM, David Chase wrote:
>>> Huh.  ba,a (annulled branch -- if I recall, the sense of the 
>>> annulled bit is reversed for ba) ought to get the job
>>> done without the delay-slot nop.
>>>
>>> David
>>>
>>> On 2013-06-07, at 6:54 AM, Morris Meyer <morris.meyer at oracle.com> 
>>> wrote:
>>>
>>>> I needed to have the delayed()->nop() in there as ba() crashed for me.
>>>>
>>>>
>>>>       --mm
>>>>
>>>>
>>>> On Jun 7, 2013, at 12:35 AM, Vladimir Kozlov 
>>>> <vladimir.kozlov at oracle.com> wrote:
>>>>
>>>>> Morris,
>>>>>
>>>>> Why you used br(always, false, pt, slow_case) instead of 
>>>>> ba(slow_case)?
>>>>>
>>>>> Which is the same but simpler and it was specially added to avoid 
>>>>> messing with parameters of br() instruction.
>>>>>
>>>>> Thanks,
>>>>> Vladimir
>>>>>
>>>>> On 6/6/13 9:22 PM, Morris Meyer wrote:
>>>>>> Folks,
>>>>>>
>>>>>> Could I get a review for this issue?  The problem exists that we
>>>>>> optimistically assign forward branch labels and re-patch later. 
>>>>>> When we
>>>>>> emit a cbcond instruction - we check if the Label out of bounds.  
>>>>>> If it
>>>>>> is already bound the check is fine - if not bound a zero offset is
>>>>>> emitted and the label is patched later
>>>>>>
>>>>>> With Vladimir Kozlov's urgings I put about 4,000 lines of changes 
>>>>>> to add
>>>>>> __FILE__ and __LINE__ parameters to every assembler.bind() call and
>>>>>> checked the return of every patched branch to find out the line and
>>>>>> location of the offending bind.  The bind distance from
>>>>>> NewInstanceStub::emit_code() in c1_CodeStubs_sparc.cpp was to far 
>>>>>> from
>>>>>> __ allocate_object macro assembler call in 
>>>>>> LIRGenerator::new_instance
>>>>>> which uses the short branch in MacroAssembler::eden_allocate()
>>>>>>
>>>>>> This change has been through JPRT.
>>>>>>
>>>>>>         --morris
>>>>>>
>>>>>> WEBREV - http://cr.openjdk.java.net/~morris/JDK-8015437.01
>>>>>> JBS - https://jbs.oracle.com/bugs/browse/JDK-8015437
>>>>>>
>>>>>>
>>