Re: [Qemu-devel] [PATCH 5/7] tcg-sparc: Implement setcond, movcond, setcond2, brcond2.

[Richard Henderson <rth@twiddle.net>]

On 12/19/2009 01:25 PM, Blue Swirl wrote:
> On Sat, Dec 19, 2009 at 5:47 PM, Richard Henderson<rth@twiddle.net>  wrote:
>> On 12/19/2009 02:31 AM, Blue Swirl wrote:
>>>>
>>>>   static inline void tcg_out_movi_imm32(TCGContext *s, int ret, uint32_t
>>>> arg)
>>>>   {
>>>> -    if (check_fit_tl(arg, 12))
>>>> +    if (check_fit_tl(arg, 13))
>>>>          tcg_out_movi_imm13(s, ret, arg);
>>>
>>> IIRC sign extension prevents this.
>>
>> Pardon?  check_fit_tl checks a signed value, the OR opcode provides one.
>>   Where's the conflict?
>
> Long time ago I tried the same change, but the generated code was not
> correct. But now it seems to work.

I can't imagine why.  I've looked at the instruction encodings very 
carefully and double-checked the arithmetic vs GCC.

I still think the change is correct.  I can probably dig up access to a 
sparc machine and verify, but I don't know that would convince you.


r~