Request for review (L): 6797305: Add LoadUB and LoadUI opcode class

[Tom Rodriguez]

>> Didn't you reorder the instruct definitions?
>
> No, I just uncommented some of them.  Maybe these have been commented
> because of this bug...

It's possible.  The ConvI2L LoadI variant was the first and only one  
before your change but now it's not.

>
>
>> I think the cisc spill
>> matching selects the first one it sees and it's possible that now  
>> it's
>> finding the LoadB variant.  Anyway, I think cisc_spill_match should  
>> be
>> fixed to handle this correctly.
>
> Do you think I can fix that or is it too complicated for a "beginner"?
> At least I will have a look at it.

You want this change:

@@ -3431,10 +3431,16 @@ int MatchNode::cisc_spill_match(FormDict
      const InstructForm *form2_inst = form2 ? form2- 
 >is_instruction() : NULL;
      const char *name_left  = mRule2->_lChild ? mRule2->_lChild- 
 >_opType : NULL;
      const char *name_right = mRule2->_rChild ? mRule2->_rChild- 
 >_opType : NULL;
+    DataType data_type = Form::none;
+    if (form->is_operand()) {
+      // Make sure the loadX matches the type of the reg
+      data_type = form->ideal_to_Reg_type(form->is_operand()- 
 >ideal_type(globals));
+    }
      // Detect reg vs (loadX memory)
      if( form->is_cisc_reg(globals)
          && form2_inst
-        && (is_load_from_memory(mRule2->_opType) != Form::none) //  
reg vs. (load memory)
+        && data_type != Form::none
+        && (is_load_from_memory(mRule2->_opType) == data_type) // reg  
vs. (load memory)
          && (name_left != NULL)       // NOT (load)
          && (name_right == NULL) ) {  // NOT (load memory foo)
        const Form *form2_left = name_left ? globals[name_left] : NULL;

This will verify that the ideal type of the register and the load  
operation are in agreement.

tom

>
>
> -- Christian
>