Commit 9e821eab authored by Richard Henderson's avatar Richard Henderson
Browse files

tcg: Clean up generic bswap64 



Based on the only current user, Sparc:

New code uses 2 constants that take 2 insns to load from constant pool,
plus 13.  Old code used 6 constants that took 1 or 2 insns to create,
plus 21.  The result is a new total of 17 vs an old total of 29.

Signed-off-by: default avatarRichard Henderson <richard.henderson@linaro.org>
parent a686dc71

tcg/tcg-op.c

+20 −27
Original line number Diff line number Diff line
@@ -1678,37 +1678,30 @@ void tcg_gen_bswap64_i64(TCGv_i64 ret, TCGv_i64 arg) 
    } else {

        TCGv_i64 t0 = tcg_temp_new_i64();

        TCGv_i64 t1 = tcg_temp_new_i64();

        TCGv_i64 t2 = tcg_temp_new_i64();



        tcg_gen_shli_i64(t0, arg, 56);



        tcg_gen_andi_i64(t1, arg, 0x0000ff00);

        tcg_gen_shli_i64(t1, t1, 40);

        tcg_gen_or_i64(t0, t0, t1);



        tcg_gen_andi_i64(t1, arg, 0x00ff0000);

        tcg_gen_shli_i64(t1, t1, 24);

        tcg_gen_or_i64(t0, t0, t1);



        tcg_gen_andi_i64(t1, arg, 0xff000000);

        tcg_gen_shli_i64(t1, t1, 8);

        tcg_gen_or_i64(t0, t0, t1);



        tcg_gen_shri_i64(t1, arg, 8);

        tcg_gen_andi_i64(t1, t1, 0xff000000);

        tcg_gen_or_i64(t0, t0, t1);



        tcg_gen_shri_i64(t1, arg, 24);

        tcg_gen_andi_i64(t1, t1, 0x00ff0000);

        tcg_gen_or_i64(t0, t0, t1);



        tcg_gen_shri_i64(t1, arg, 40);

        tcg_gen_andi_i64(t1, t1, 0x0000ff00);

        tcg_gen_or_i64(t0, t0, t1);

                                        /* arg = abcdefgh */

        tcg_gen_movi_i64(t2, 0x00ff00ff00ff00ffull);

        tcg_gen_shri_i64(t0, arg, 8);   /*  t0 = .abcdefg */

        tcg_gen_and_i64(t1, arg, t2);   /*  t1 = .b.d.f.h */

        tcg_gen_and_i64(t0, t0, t2);    /*  t0 = .a.c.e.g */

        tcg_gen_shli_i64(t1, t1, 8);    /*  t1 = b.d.f.h. */

        tcg_gen_or_i64(ret, t0, t1);    /* ret = badcfehg */



        tcg_gen_movi_i64(t2, 0x0000ffff0000ffffull);

        tcg_gen_shri_i64(t0, ret, 16);  /*  t0 = ..badcfe */

        tcg_gen_and_i64(t1, ret, t2);   /*  t1 = ..dc..hg */

        tcg_gen_and_i64(t0, t0, t2);    /*  t0 = ..ba..fe */

        tcg_gen_shli_i64(t1, t1, 16);   /*  t1 = dc..hg.. */

        tcg_gen_or_i64(ret, t0, t1);    /* ret = dcbahgfe */



        tcg_gen_shri_i64(t0, ret, 32);  /*  t0 = ....dcba */

        tcg_gen_shli_i64(t1, ret, 32);  /*  t1 = hgfe.... */

        tcg_gen_or_i64(ret, t0, t1);    /* ret = hgfedcba */



        tcg_gen_shri_i64(t1, arg, 56);

        tcg_gen_or_i64(ret, t0, t1);

        tcg_temp_free_i64(t0);

        tcg_temp_free_i64(t1);

        tcg_temp_free_i64(t2);

    }

}