diff --git a/target/ppc/translate/fixedpoint-impl.c.inc b/target/ppc/translate/fixedpoint-impl.c.inc index 20ea484c3d..02d86b77a8 100644 --- a/target/ppc/translate/fixedpoint-impl.c.inc +++ b/target/ppc/translate/fixedpoint-impl.c.inc @@ -484,33 +484,35 @@ static bool trans_PEXTD(DisasContext *ctx, arg_X *a) static bool trans_ADDG6S(DisasContext *ctx, arg_X *a) { - const uint64_t carry_bits = 0x1111111111111111ULL; - TCGv t0, t1, carry, zero = tcg_constant_tl(0); + const target_ulong carry_bits = (target_ulong)-1 / 0xf; + TCGv in1, in2, carryl, carryh, tmp; + TCGv zero = tcg_constant_tl(0); REQUIRE_INSNS_FLAGS2(ctx, BCDA_ISA206); - t0 = tcg_temp_new(); - t1 = tcg_const_tl(0); - carry = tcg_const_tl(0); + in1 = cpu_gpr[a->ra]; + in2 = cpu_gpr[a->rb]; + tmp = tcg_temp_new(); + carryl = tcg_temp_new(); + carryh = tcg_temp_new(); - for (int i = 0; i < 16; i++) { - tcg_gen_shri_tl(t0, cpu_gpr[a->ra], i * 4); - tcg_gen_andi_tl(t0, t0, 0xf); - tcg_gen_add_tl(t1, t1, t0); + /* Addition with carry. */ + tcg_gen_add2_tl(carryl, carryh, in1, zero, in2, zero); + /* Addition without carry. */ + tcg_gen_xor_tl(tmp, in1, in2); + /* Difference between the two is carry in to each bit. */ + tcg_gen_xor_tl(carryl, carryl, tmp); - tcg_gen_shri_tl(t0, cpu_gpr[a->rb], i * 4); - tcg_gen_andi_tl(t0, t0, 0xf); - tcg_gen_add_tl(t1, t1, t0); + /* + * The carry-out that we're looking for is the carry-in to + * the next nibble. Shift the double-word down one nibble, + * which puts all of the bits back into one word. + */ + tcg_gen_extract2_tl(carryl, carryl, carryh, 4); - tcg_gen_andi_tl(t1, t1, 0x10); - tcg_gen_setcond_tl(TCG_COND_NE, t1, t1, zero); - - tcg_gen_shli_tl(t0, t1, i * 4); - tcg_gen_or_tl(carry, carry, t0); - } - - tcg_gen_xori_tl(carry, carry, (target_long)carry_bits); - tcg_gen_muli_tl(cpu_gpr[a->rt], carry, 6); + /* Invert, isolate the carry bits, and produce 6's. */ + tcg_gen_andc_tl(carryl, tcg_constant_tl(carry_bits), carryl); + tcg_gen_muli_tl(cpu_gpr[a->rt], carryl, 6); return true; }