Commit ee924fa6 authored by Richard Henderson's avatar Richard Henderson
Browse files

tcg-ppc64: Improve constant add and sub ops. 



Improve constant addition -- previously we'd emit useless addi with 0.
Use new constraints to force the driver to pull full 64-bit constants
into a register.

Reviewed-by: default avatarAurelien Jarno <aurelien@aurel32.net>
Signed-off-by: default avatarRichard Henderson <rth@twiddle.net>
parent 3d582c61

tcg/ppc64/tcg-target.c

+64 −44
Original line number Diff line number Diff line
@@ -988,32 +988,6 @@ static void tcg_out_st (TCGContext *s, TCGType type, TCGReg arg, TCGReg arg1, 
        tcg_out_ldsta (s, arg, arg1, arg2, STD, STDX);

}



static void ppc_addi32(TCGContext *s, TCGReg rt, TCGReg ra, tcg_target_long si)

{

    if (!si && rt == ra)

        return;



    if (si == (int16_t) si)

        tcg_out32(s, ADDI | TAI(rt, ra, si));

    else {

        uint16_t h = ((si >> 16) & 0xffff) + ((uint16_t) si >> 15);

        tcg_out32(s, ADDIS | TAI(rt, ra, h));

        tcg_out32(s, ADDI | TAI(rt, rt, si));

    }

}



static void ppc_addi64(TCGContext *s, TCGReg rt, TCGReg ra, tcg_target_long si)

{

    /* XXX: suboptimal */

    if (si == (int16_t) si

        || ((((uint64_t) si >> 31) == 0) && (si & 0x8000) == 0))

        ppc_addi32 (s, rt, ra, si);

    else {

        tcg_out_movi (s, TCG_TYPE_I64, 0, si);

        tcg_out32(s, ADD | TAB(rt, ra, 0));

    }

}



static void tcg_out_cmp (TCGContext *s, int cond, TCGArg arg1, TCGArg arg2,

                         int const_arg2, int cr, int arch64)

{
@@ -1232,6 +1206,7 @@ void ppc_tb_set_jmp_target (unsigned long jmp_addr, unsigned long addr) 
static void tcg_out_op (TCGContext *s, TCGOpcode opc, const TCGArg *args,

                        const int *const_args)

{

    TCGArg a0, a1, a2;

    int c;



    switch (opc) {
@@ -1320,16 +1295,31 @@ static void tcg_out_op (TCGContext *s, TCGOpcode opc, const TCGArg *args, 
        break;



    case INDEX_op_add_i32:

        if (const_args[2])

            ppc_addi32 (s, args[0], args[1], args[2]);

        else

            tcg_out32 (s, ADD | TAB (args[0], args[1], args[2]));

        a0 = args[0], a1 = args[1], a2 = args[2];

        if (const_args[2]) {

            int32_t l, h;

        do_addi_32:

            l = (int16_t)a2;

            h = a2 - l;

            if (h) {

                tcg_out32(s, ADDIS | TAI(a0, a1, h >> 16));

                a1 = a0;

            }

            if (l || a0 != a1) {

                tcg_out32(s, ADDI | TAI(a0, a1, l));

            }

        } else {

            tcg_out32(s, ADD | TAB(a0, a1, a2));

        }

        break;

    case INDEX_op_sub_i32:

        if (const_args[2])

            ppc_addi32 (s, args[0], args[1], -args[2]);

        else

            tcg_out32 (s, SUBF | TAB (args[0], args[2], args[1]));

        a0 = args[0], a1 = args[1], a2 = args[2];

        if (const_args[2]) {

            a2 = -a2;

            goto do_addi_32;

        } else {

            tcg_out32(s, SUBF | TAB(a0, a2, a1));

        }

        break;



    case INDEX_op_and_i64:
@@ -1459,16 +1449,46 @@ static void tcg_out_op (TCGContext *s, TCGOpcode opc, const TCGArg *args, 
        break;



    case INDEX_op_add_i64:

        if (const_args[2])

            ppc_addi64 (s, args[0], args[1], args[2]);

        else

            tcg_out32 (s, ADD | TAB (args[0], args[1], args[2]));

        a0 = args[0], a1 = args[1], a2 = args[2];

        if (const_args[2]) {

            int32_t l0, h1, h2;

        do_addi_64:

            /* We can always split any 32-bit signed constant into 3 pieces.

               Note the positive 0x80000000 coming from the sub_i64 path,

               handled with the same code we need for eg 0x7fff8000.  */

            assert(a2 == (int32_t)a2 || a2 == 0x80000000);

            l0 = (int16_t)a2;

            h1 = a2 - l0;

            h2 = 0;

            if (h1 < 0 && (int64_t)a2 > 0) {

                h2 = 0x40000000;

                h1 = a2 - h2 - l0;

            }

            assert((TCGArg)h2 + h1 + l0 == a2);



            if (h2) {

                tcg_out32(s, ADDIS | TAI(a0, a1, h2 >> 16));

                a1 = a0;

            }

            if (h1) {

                tcg_out32(s, ADDIS | TAI(a0, a1, h1 >> 16));

                a1 = a0;

            }

            if (l0 || a0 != a1) {

                tcg_out32(s, ADDI | TAI(a0, a1, l0));

            }

        } else {

            tcg_out32(s, ADD | TAB(a0, a1, a2));

        }

        break;

    case INDEX_op_sub_i64:

        if (const_args[2])

            ppc_addi64 (s, args[0], args[1], -args[2]);

        else

            tcg_out32 (s, SUBF | TAB (args[0], args[2], args[1]));

        a0 = args[0], a1 = args[1], a2 = args[2];

        if (const_args[2]) {

            a2 = -a2;

            goto do_addi_64;

        } else {

            tcg_out32(s, SUBF | TAB(a0, a2, a1));

        }

        break;



    case INDEX_op_shl_i64:
@@ -1634,8 +1654,8 @@ static const TCGTargetOpDef ppc_op_defs[] = { 
    { INDEX_op_neg_i32, { "r", "r" } },

    { INDEX_op_not_i32, { "r", "r" } },



    { INDEX_op_add_i64, { "r", "r", "ri" } },

    { INDEX_op_sub_i64, { "r", "r", "ri" } },

    { INDEX_op_add_i64, { "r", "r", "rT" } },

    { INDEX_op_sub_i64, { "r", "r", "rT" } },

    { INDEX_op_and_i64, { "r", "r", "rU" } },

    { INDEX_op_or_i64, { "r", "r", "rU" } },

    { INDEX_op_xor_i64, { "r", "r", "rU" } },