Commit e0a42ebc authored by Edgar E. Iglesias's avatar Edgar E. Iglesias
Browse files

microblaze: Improve subkc 



Move code from the helper into the translator. The remaining
helper parts can reuse helper_addkc, making it possible to
remove helper_subkc entirely.

Signed-off-by: default avatarEdgar E. Iglesias <edgar.iglesias@gmail.com>
parent 7e9e4330

target-microblaze/helper.h

+0 −1
Original line number Diff line number Diff line
@@ -3,7 +3,6 @@ 
DEF_HELPER_1(raise_exception, void, i32)

DEF_HELPER_0(debug, void)

DEF_HELPER_FLAGS_3(addkc, TCG_CALL_PURE | TCG_CALL_CONST, i32, i32, i32, i32)

DEF_HELPER_4(subkc, i32, i32, i32, i32, i32)

DEF_HELPER_2(cmp, i32, i32, i32)

DEF_HELPER_2(cmpu, i32, i32, i32)

target-microblaze/op_helper.c

+0 −22
Original line number Diff line number Diff line
@@ -138,28 +138,6 @@ uint32_t helper_addkc(uint32_t a, uint32_t b, uint32_t cf) 
    return ncf;

}



uint32_t helper_subkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)

{

    uint32_t d, cf = 1, ncf;



    if (c)

        cf = env->sregs[SR_MSR] >> 31; 

    assert(cf == 0 || cf == 1);

    d = b + ~a + cf;



    if (!k) {

        ncf = compute_carry(b, ~a, cf);

        assert(ncf == 0 || ncf == 1);

        if (ncf)

            env->sregs[SR_MSR] |= MSR_C | MSR_CC;

        else

            env->sregs[SR_MSR] &= ~(MSR_C | MSR_CC);

    }

    D(qemu_log("%x = %x + %x cf=%d ncf=%d k=%d c=%d\n",

               d, a, b, cf, ncf, k, c));

    return d;

}



static inline int div_prepare(uint32_t a, uint32_t b)

{

    if (b == 0) {

target-microblaze/translate.c

+49 −15
Original line number Diff line number Diff line
@@ -247,6 +247,7 @@ static void dec_add(DisasContext *dc) 
static void dec_sub(DisasContext *dc)

{

    unsigned int u, cmp, k, c;

    TCGv cf, na;



    u = dc->imm & 2;

    k = dc->opcode & 4;
@@ -261,25 +262,58 @@ static void dec_sub(DisasContext *dc) 
            else

                gen_helper_cmp(cpu_R[dc->rd], cpu_R[dc->ra], cpu_R[dc->rb]);

        }

    } else {

        return;

    }



    LOG_DIS("sub%s%s r%d, r%d r%d\n",

             k ? "k" : "",  c ? "c" : "", dc->rd, dc->ra, dc->rb);



        if (!k || c) {

            TCGv t;

            t = tcg_temp_new();

            if (dc->rd)

                gen_helper_subkc(cpu_R[dc->rd], cpu_R[dc->ra], *(dec_alu_op_b(dc)),

                                 tcg_const_tl(k), tcg_const_tl(c));

            else

                gen_helper_subkc(t, cpu_R[dc->ra], *(dec_alu_op_b(dc)),

                                 tcg_const_tl(k), tcg_const_tl(c));

            tcg_temp_free(t);

        }

        else if (dc->rd)

    /* Take care of the easy cases first.  */

    if (k) {

        /* k - keep carry, no need to update MSR.  */

        /* If rd == r0, it's a nop.  */

        if (dc->rd) {

            tcg_gen_sub_tl(cpu_R[dc->rd], *(dec_alu_op_b(dc)), cpu_R[dc->ra]);



            if (c) {

                /* c - Add carry into the result.  */

                cf = tcg_temp_new();



                read_carry(dc, cf);

                tcg_gen_add_tl(cpu_R[dc->rd], cpu_R[dc->rd], cf);

                tcg_temp_free(cf);

            }

        }

        return;

    }



    /* From now on, we can assume k is zero.  So we need to update MSR.  */

    /* Extract carry. And complement a into na.  */

    cf = tcg_temp_new();

    na = tcg_temp_new();

    if (c) {

        read_carry(dc, cf);

    } else {

        tcg_gen_movi_tl(cf, 1);

    }



    /* d = b + ~a + c. carry defaults to 1.  */

    tcg_gen_not_tl(na, cpu_R[dc->ra]);



    if (dc->rd) {

        TCGv ncf = tcg_temp_new();

        gen_helper_addkc(ncf, na, *(dec_alu_op_b(dc)), cf);

        tcg_gen_add_tl(cpu_R[dc->rd], na, *(dec_alu_op_b(dc)));

        tcg_gen_add_tl(cpu_R[dc->rd], cpu_R[dc->rd], cf);

        write_carry(dc, ncf);

        tcg_temp_free(ncf);

    } else {

        gen_helper_addkc(cf, na, *(dec_alu_op_b(dc)), cf);

        write_carry(dc, cf);

    }

    tcg_temp_free(cf);

    tcg_temp_free(na);

}



static void dec_pattern(DisasContext *dc)

{