On Thu, Sep 27, 2012 at 10:19:51AM -0700, Richard Henderson wrote:
> Reduces code duplication and prefers
>
> movcond d, c1, c2, const, s
> to
> movcond d, c1, c2, s, const
>
> Signed-off-by: Richard Henderson <r...@twiddle.net>
> ---
> tcg/optimize.c | 54 ++++++++++++++++++++++--------------------------------
> 1 file changed, 22 insertions(+), 32 deletions(-)
>
> diff --git a/tcg/optimize.c b/tcg/optimize.c
> index 35532a1..55f2a24 100644
> --- a/tcg/optimize.c
> +++ b/tcg/optimize.c
> @@ -382,6 +382,21 @@ static TCGArg do_constant_folding_cond(TCGOpcode op,
> TCGArg x,
> tcg_abort();
> }
>
> +static bool swap_commutative(TCGArg dest, TCGArg *p1, TCGArg *p2)
> +{
> + TCGArg a1 = *p1, a2 = *p2;
> + /* Prefer the constant in second argument, and then the form
> + op a, a, b, which is better handled on non-RISC hosts. */
> + if (temps[a1].state == TCG_TEMP_CONST
> + || (dest != (TCGArg)-1 && dest == a2
> + && temps[a2].state != TCG_TEMP_CONST)) {
> + *p1 = a2;
> + *p2 = a1;
> + return true;
> + }
> + return false;
> +}
> +
> /* Propagate constants and copies, fold constant expressions. */
> static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
> TCGArg *args, TCGOpDef *tcg_op_defs)
> @@ -391,7 +406,6 @@ static TCGArg *tcg_constant_folding(TCGContext *s,
> uint16_t *tcg_opc_ptr,
> const TCGOpDef *def;
> TCGArg *gen_args;
> TCGArg tmp;
> - TCGCond cond;
>
> /* Array VALS has an element for each temp.
> If this temp holds a constant then its value is kept in VALS' element.
> @@ -434,52 +448,28 @@ static TCGArg *tcg_constant_folding(TCGContext *s,
> uint16_t *tcg_opc_ptr,
> CASE_OP_32_64(eqv):
> CASE_OP_32_64(nand):
> CASE_OP_32_64(nor):
> - /* Prefer the constant in second argument, and then the form
> - op a, a, b, which is better handled on non-RISC hosts. */
> - if (temps[args[1]].state == TCG_TEMP_CONST || (args[0] == args[2]
> - && temps[args[2]].state != TCG_TEMP_CONST)) {
> - tmp = args[1];
> - args[1] = args[2];
> - args[2] = tmp;
> - }
> + swap_commutative(args[0], &args[1], &args[2]);
> break;
> CASE_OP_32_64(brcond):
> - if (temps[args[0]].state == TCG_TEMP_CONST
> - && temps[args[1]].state != TCG_TEMP_CONST) {
> - tmp = args[0];
> - args[0] = args[1];
> - args[1] = tmp;
> + if (swap_commutative(-1, &args[0], &args[1])) {
> args[2] = tcg_swap_cond(args[2]);
> }
> break;
> CASE_OP_32_64(setcond):
> - if (temps[args[1]].state == TCG_TEMP_CONST
> - && temps[args[2]].state != TCG_TEMP_CONST) {
> - tmp = args[1];
> - args[1] = args[2];
> - args[2] = tmp;
> + if (swap_commutative(args[0], &args[1], &args[2])) {
> args[3] = tcg_swap_cond(args[3]);
> }
> break;
> CASE_OP_32_64(movcond):
> - cond = args[5];
> - if (temps[args[1]].state == TCG_TEMP_CONST
> - && temps[args[2]].state != TCG_TEMP_CONST) {
> - tmp = args[1];
> - args[1] = args[2];
> - args[2] = tmp;
> - cond = tcg_swap_cond(cond);
> + if (swap_commutative(-1, &args[1], &args[2])) {
> + args[5] = tcg_swap_cond(args[5]);
> }
> /* For movcond, we canonicalize the "false" input reg to match
> the destination reg so that the tcg backend can implement
> a "move if true" operation. */
> - if (args[0] == args[3]) {
> - tmp = args[3];
> - args[3] = args[4];
> - args[4] = tmp;
> - cond = tcg_invert_cond(cond);
> + if (swap_commutative(args[0], &args[4], &args[3])) {
> + args[5] = tcg_invert_cond(args[5]);
> }
> - args[5] = cond;
> default:
> break;
> }
Reviewed-by: Aurelien Jarno <aurel...@aurel32.net>
--
Aurelien Jarno GPG: 1024D/F1BCDB73
aurel...@aurel32.net http://www.aurel32.net
