Possible bug in regrename.c???
Anders Ådland
aaadland@atmel.no
Tue Jul 29 11:45:00 GMT 2003
movhi is accepting all general operands, which makes GCC able to generate
this pattern. Use a predicate function and constraint letters to restrict
which patterns movhi is accepting. The avr port is dividing movhi into a
define_expand and a define_insn, which is a good solution.
Anders
On Mon, 28 Jul 2003 19:03:39 +1000, Marty Hauff <marty.hauff@rmit.edu.au>
wrote:
> The port that I'm doing is based around the AVR and it already has
> GO_IF_LEGITIMATE_ADDRESS defined. The change that I have made which
> seems to break the port is modifying the movhi RTX to the following:
>
> (define_insn "movhi" [(set (match_operand:HI 0 "general_operand" "")
> (match_operand:HI 1 "general_operand" ""))]
> ""
> ";movhi_" )
>
> I'm not sure where the GO_IF_LEGITIMATE_ADDRESS macro is used but it
> certainly isn't called anywhere near where the code is segfaulting. A
> better macro definition may prevent the offending RTX from being created
> in the first place but as far as I can see, the offending RTX is legal
> and therefore should not cause the compiler to segfault???
>
> I'll follow your suggestion through some more though...
>
> Marty Moose
>
>>>> Anders Ã
dland <aaadland@atmel.no> 07/28/03 16:56 PM >>>
> On Sun, 27 Jul 2003 16:08:39 +1000, Marty Hauff <marty.hauff@rmit.edu.au>
> wrote:
>
>> I'm still new to GCC but I stumbled across the following anomoly whilst
>> trying to make a new port.
>>
>> The following RTX:
>> (set (mem:HI (reg/v/f:HI 8 r8 [44]) [8 S2 A8])
>> (mem:HI (pre_dec:HI (mem:HI (plus:HI (reg/f:HI 28 r28)
>> (const_int 3 [0x3])) [17 S2 A8])) [8 S2 A8]))
>>
>> causes set_value_regno() to segfault.
>
> I'm new to GCC too, but had a similar problem. It looks like a pseudo
> register is replaced by a memory reference. Is GO_IF_LEGITIMATE_ADDRESS
> defined properly, with one strict and one non-strict variant?
>
> Anders
>
>
>
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