Richard Henderson <richard.hender...@linaro.org> writes:
> Most of these are handled by creating a fold_const2_commutative
> to handle all of the binary operators. The rest were already
> handled on a case-by-case basis in the switch, and have their
> own fold function in which to place the call.
>
> We now have only one major switch on TCGOpcode.
>
> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
> ---
> tcg/optimize.c | 128 ++++++++++++++++++++++---------------------------
> 1 file changed, 56 insertions(+), 72 deletions(-)
>
> diff --git a/tcg/optimize.c b/tcg/optimize.c
> index ba068e7d3e..92b35a8c3f 100644
> --- a/tcg/optimize.c
> +++ b/tcg/optimize.c
> @@ -696,6 +696,12 @@ static bool fold_const2(OptContext *ctx, TCGOp *op)
> return false;
> }
>
> +static bool fold_const2_commutative(OptContext *ctx, TCGOp *op)
> +{
> + swap_commutative(op->args[0], &op->args[1], &op->args[2]);
> + return fold_const2(ctx, op);
> +}
> +
> static bool fold_masks(OptContext *ctx, TCGOp *op)
> {
> uint64_t a_mask = ctx->a_mask;
> @@ -832,7 +838,7 @@ static bool fold_xx_to_x(OptContext *ctx, TCGOp *op)
>
> static bool fold_add(OptContext *ctx, TCGOp *op)
> {
> - if (fold_const2(ctx, op) ||
> + if (fold_const2_commutative(ctx, op) ||
> fold_xi_to_x(ctx, op, 0)) {
> return true;
> }
> @@ -891,6 +897,9 @@ static bool fold_addsub2(OptContext *ctx, TCGOp *op, bool
> add)
>
> static bool fold_add2(OptContext *ctx, TCGOp *op)
> {
> + swap_commutative(op->args[0], &op->args[2], &op->args[4]);
> + swap_commutative(op->args[1], &op->args[3], &op->args[5]);
> +
> return fold_addsub2(ctx, op, true);
> }
>
> @@ -898,7 +907,7 @@ static bool fold_and(OptContext *ctx, TCGOp *op)
> {
> uint64_t z1, z2;
>
> - if (fold_const2(ctx, op) ||
> + if (fold_const2_commutative(ctx, op) ||
> fold_xi_to_i(ctx, op, 0) ||
> fold_xi_to_x(ctx, op, -1) ||
> fold_xx_to_x(ctx, op)) {
> @@ -950,8 +959,13 @@ static bool fold_andc(OptContext *ctx, TCGOp *op)
> static bool fold_brcond(OptContext *ctx, TCGOp *op)
> {
> TCGCond cond = op->args[2];
> - int i = do_constant_folding_cond(ctx->type, op->args[0], op->args[1],
> cond);
> + int i;
>
> + if (swap_commutative(-1, &op->args[0], &op->args[1])) {
I find this a bit magical. I couldn't find anything about TCGArg except
it's type:
typedef tcg_target_ulong TCGArg;
so I'm not sure what to make of -1 in this case. I guess it just means
we never have a (sum == 0 && dest == a2) leg but it's not obvious
reading the fold code.
>
> + if (swap_commutative(-1, &op->args[1], &op->args[2])) {
> + op->args[5] = cond = tcg_swap_cond(cond);
> + }
Also here.
<snip>
--
Alex Bennée
