On 1/26/23 14:45, Philippe Mathieu-Daudé wrote:
+ /* Compare i128 */
+ tcg_gen_xor_i64(t0, TCGV128_LOW(oldv), TCGV128_LOW(cmpv));
+ tcg_gen_xor_i64(t1, TCGV128_HIGH(oldv), TCGV128_HIGH(cmpv));
+ tcg_gen_or_i64(t0, t0, t1);
Can we skip the OR ...
+ /* tmpv = equal ? newv : oldv */
+ tcg_gen_movcond_i64(TCG_COND_EQ, TCGV128_LOW(tmpv), t0, z,
+ TCGV128_LOW(newv), TCGV128_LOW(oldv));
+ tcg_gen_movcond_i64(TCG_COND_EQ, TCGV128_HIGH(tmpv), t0, z,
... and test t1 here to partially update LO/HI? (we could remove t1 and
just use t0 as twice 'xor + movcond' but the code is less readable).
No.
We want equality on the entire 128-bit comparison to control the conditional
moves.
r~
