[lra] patch to revert a code from previous patch.

[Vladimir Makarov]

On 12-10-15 3:10 PM, Richard Sandiford wrote:
> Vladimir Makarov <vmakarov@redhat.com> writes:
>>     After committing a patch yesterday to implement proposals from a
>> review, I found that GCC crashes on SPEC2000 gap.  LRA is trying to find
>> a mode of operand (const_int 1) in *lea_general_1 insn and can not find
>> it as the operand and insn template operand has VOIDmode.
>>
>> There are still cases when context lookup is necessary to find a mode of
>> the operand.  So I am reversing the change I did yesterday.
>>
>> The patch is committed as rev. 192462.
>>
>> 2012-10-15  Vladimir Makarov  <vmakarov@redhat.com>
>>
>>           * lra-int.h (lra_get_mode): Remove.
>>           * lra-constraints.c (find_mode, get_op_mode): New functions.
>>           (match_reload): Use get_op_mode instead of lra_get_mode.
>>           (process_alt_operands, curr_insn_transform): Ditto.
> But my objection to this code still stands.  It's wrong to assume
> that an operand to an rtx has the same mode as the containing rtx.
I use it as only the last chance to find a mode for a constant.
> Please add a testcase that shows the problem.
>
>
It is a SPEC2000 test file.  I don't think the license permits it.

In insn:

(define_insn_and_split "*lea_general_1"
   [(set (match_operand 0 "register_operand" "=r")
     (plus (plus (match_operand 1 "index_register_operand" "l")
             (match_operand 2 "register_operand" "r"))
           (match_operand 3 "immediate_operand" "i")))]

one operand is (const_int 1).  Its mode is VOIDmode.  recog_data mode is 
VOIDmode.  The patch takes right mode from PLUS containing it.