On 04/08/2010 09:32 AM, Richard Henderson wrote:
>>> +static void tcg_out_ori(TCGContext *s, int ret, int arg, tcg_target_ulong
>>> m)
>>> +{
>>> + if (m == 0) {
>>> + tcg_out_mov(s, ret, arg);
>>> + } else if (m == -1) {
>>> + tcg_out_movi(s, TCG_TYPE_I32, ret, -1);
>>
>> Those cases are already eliminated in tcg/tcg-op.h. This code looks
>> redundant.
>
> The cases eliminated in tcg-op.h are with immediate constants.
> There is no generic code in tcg.c to eliminate these cases
> after constant propagation. However, I can remove them with...
For the record, a real case that appears in linux-test-0.3 sparc:
0x435e8ac4: andcc %g0, %g0, %o4
---- 0x435e8ac4
movi_i32 tmp19,$0x0
movi_i32 tmp20,$0x0
and_i32 loc4,tmp19,tmp20
mov_i32 cc_dst,loc4
movi_i32 cc_op,$0xb
st_i32 loc4,regwptr,$0x10
The and_i32 there is "loc4 = 0 & 0".
I've no idea why the original sparc code uses this instruction.
r~
