Commit acf12465 authored by Aurelien Jarno's avatar Aurelien Jarno
Browse files

target-mips: implement movn/movz using movcond 



Avoid the branches in movn/movz implementation and replace them with
movcond. Also update a wrong command.

Reviewed-by: default avatarRichard Henderson <rth@twiddle.net>
Signed-off-by: default avatarAurelien Jarno <aurelien@aurel32.net>
parent 2d2826b9

target-mips/translate.c

+12 −15
Original line number Diff line number Diff line
@@ -2359,35 +2359,32 @@ static void gen_cond_move(CPUMIPSState *env, DisasContext *ctx, uint32_t opc, 
                          int rd, int rs, int rt)

{

    const char *opn = "cond move";

    int l1;

    TCGv t0, t1, t2;



    if (rd == 0) {

        /* If no destination, treat it as a NOP.

           For add & sub, we must generate the overflow exception when needed. */

        /* If no destination, treat it as a NOP. */

        MIPS_DEBUG("NOP");

        return;

    }



    l1 = gen_new_label();

    t0 = tcg_temp_new();

    gen_load_gpr(t0, rt);

    t1 = tcg_const_tl(0);

    t2 = tcg_temp_new();

    gen_load_gpr(t2, rs);

    switch (opc) {

    case OPC_MOVN:

        if (likely(rt != 0))

            tcg_gen_brcondi_tl(TCG_COND_EQ, cpu_gpr[rt], 0, l1);

        else

            tcg_gen_br(l1);

        tcg_gen_movcond_tl(TCG_COND_NE, cpu_gpr[rd], t0, t1, t2, cpu_gpr[rd]);

        opn = "movn";

        break;

    case OPC_MOVZ:

        if (likely(rt != 0))

            tcg_gen_brcondi_tl(TCG_COND_NE, cpu_gpr[rt], 0, l1);

        tcg_gen_movcond_tl(TCG_COND_EQ, cpu_gpr[rd], t0, t1, t2, cpu_gpr[rd]);

        opn = "movz";

        break;

    }

    if (rs != 0)

        tcg_gen_mov_tl(cpu_gpr[rd], cpu_gpr[rs]);

    else

        tcg_gen_movi_tl(cpu_gpr[rd], 0);

    gen_set_label(l1);

    tcg_temp_free(t2);

    tcg_temp_free(t1);

    tcg_temp_free(t0);



    (void)opn; /* avoid a compiler warning */

    MIPS_DEBUG("%s %s, %s, %s", opn, regnames[rd], regnames[rs], regnames[rt]);