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| author | Richard Henderson <richard.henderson@linaro.org> | 2024-12-22 16:08:42 -0800 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2025-06-30 07:42:37 -0600 |
| commit | d4d441e3a1c9f485a27662890ec7c009a056fda8 (patch) | |
| tree | e369b87bd04ce48b99248f4941a809afcc73c06e | |
| parent | 1e2edf85cc4755c844f9c98cbe52ac63d7d1fb18 (diff) | |
| download | qemu-d4d441e3a1c9f485a27662890ec7c009a056fda8.zip qemu-d4d441e3a1c9f485a27662890ec7c009a056fda8.tar.gz qemu-d4d441e3a1c9f485a27662890ec7c009a056fda8.tar.bz2 | |
tcg/optimize: Build and use o_bits in fold_andc
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
| -rw-r--r-- | tcg/optimize.c | 23 |
1 files changed, 8 insertions, 15 deletions
diff --git a/tcg/optimize.c b/tcg/optimize.c index d9ccbb3..123734b 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -1452,7 +1452,7 @@ static bool fold_and(OptContext *ctx, TCGOp *op) static bool fold_andc(OptContext *ctx, TCGOp *op) { - uint64_t z_mask, s_mask; + uint64_t z_mask, o_mask, s_mask, a_mask; TempOptInfo *t1, *t2; if (fold_const2(ctx, op) || @@ -1464,7 +1464,6 @@ static bool fold_andc(OptContext *ctx, TCGOp *op) t1 = arg_info(op->args[1]); t2 = arg_info(op->args[2]); - z_mask = t1->z_mask; if (ti_is_const(t2)) { /* Fold andc r,x,i to and r,x,~i. */ @@ -1485,20 +1484,14 @@ static bool fold_andc(OptContext *ctx, TCGOp *op) return fold_and(ctx, op); } - /* - * Known-zeros does not imply known-ones. Therefore unless - * arg2 is constant, we can't infer anything from it. - */ - if (ti_is_const(t2)) { - uint64_t v2 = ti_const_val(t2); - if (fold_affected_mask(ctx, op, z_mask & v2)) { - return true; - } - z_mask &= ~v2; - } - + z_mask = t1->z_mask & ~t2->o_mask; + o_mask = t1->o_mask & ~t2->z_mask; s_mask = t1->s_mask & t2->s_mask; - return fold_masks_zs(ctx, op, z_mask, s_mask); + + /* Affected bits are those not known zero, masked by those known zero. */ + a_mask = t1->z_mask & t2->z_mask; + + return fold_masks_zosa(ctx, op, z_mask, o_mask, s_mask, a_mask); } static bool fold_bitsel_vec(OptContext *ctx, TCGOp *op) |