Optimize the check for negative bignums. #405
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| @@ -543,13 +543,13 @@ MVMObject *MVM_bigint_div(MVMThreadContext *tc, MVMObject *result_type, MVMObjec | |||
| bc = get_bigint_body(tc, result); | |||
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| if (MVM_BIGINT_IS_BIG(ba)) { | |||
| cmp_a = mp_cmp_d(ba->u.bigint, 0); | |||
| cmp_a = SIGN(ba->u.bigint) == MP_NEG ? MP_LT : MP_GT; | |||
| } else { | |||
| // we only care about MP_LT or !MP_LT, so we give MP_GT even for 0. | |||
| cmp_a = ba->u.smallint.value < 0 ? MP_LT : MP_GT; | |||
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We could probably make this code use MP_NEG and MP_ZPOS instead
We save a function call for every check.
Two mp_neg calls have no effect and mp_get_int64 doesn't care about the sign.
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@LemonBoy any reason to close this besides "too slow to get review"? Finally got around to looking at it now, and it looks fine. |
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None in particular, it got killed in a housekeeping spree :) |
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I seem to recall this was related to https://rt.perl.org/Ticket/Display.html?id=128035, was the patch actually applied? |
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D'oh, I forgot. It's applied now, though it was a welcome optimization rather than a behavior change, so no impact on the RT in question. |
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We save a function call for every check.