diff options
Diffstat (limited to 'target-sh4')
| -rw-r--r-- | target-sh4/translate.c | 53 |
1 files changed, 22 insertions, 31 deletions
diff --git a/target-sh4/translate.c b/target-sh4/translate.c index c8dd3a71a0..724c0e7106 100644 --- a/target-sh4/translate.c +++ b/target-sh4/translate.c @@ -832,37 +832,28 @@ static void _decode_opc(DisasContext * ctx) return; case 0x400c: /* shad Rm,Rn */ { - TCGLabel *label1 = gen_new_label(); - TCGLabel *label2 = gen_new_label(); - TCGLabel *label3 = gen_new_label(); - TCGLabel *label4 = gen_new_label(); - TCGv shift; - tcg_gen_brcondi_i32(TCG_COND_LT, REG(B7_4), 0, label1); - /* Rm positive, shift to the left */ - shift = tcg_temp_new(); - tcg_gen_andi_i32(shift, REG(B7_4), 0x1f); - tcg_gen_shl_i32(REG(B11_8), REG(B11_8), shift); - tcg_temp_free(shift); - tcg_gen_br(label4); - /* Rm negative, shift to the right */ - gen_set_label(label1); - shift = tcg_temp_new(); - tcg_gen_andi_i32(shift, REG(B7_4), 0x1f); - tcg_gen_brcondi_i32(TCG_COND_EQ, shift, 0, label2); - tcg_gen_not_i32(shift, REG(B7_4)); - tcg_gen_andi_i32(shift, shift, 0x1f); - tcg_gen_addi_i32(shift, shift, 1); - tcg_gen_sar_i32(REG(B11_8), REG(B11_8), shift); - tcg_temp_free(shift); - tcg_gen_br(label4); - /* Rm = -32 */ - gen_set_label(label2); - tcg_gen_brcondi_i32(TCG_COND_LT, REG(B11_8), 0, label3); - tcg_gen_movi_i32(REG(B11_8), 0); - tcg_gen_br(label4); - gen_set_label(label3); - tcg_gen_movi_i32(REG(B11_8), 0xffffffff); - gen_set_label(label4); + TCGv t0 = tcg_temp_new(); + TCGv t1 = tcg_temp_new(); + TCGv t2 = tcg_temp_new(); + + tcg_gen_andi_i32(t0, REG(B7_4), 0x1f); + + /* positive case: shift to the left */ + tcg_gen_shl_i32(t1, REG(B11_8), t0); + + /* negative case: shift to the right in two steps to + correctly handle the -32 case */ + tcg_gen_xori_i32(t0, t0, 0x1f); + tcg_gen_sar_i32(t2, REG(B11_8), t0); + tcg_gen_sari_i32(t2, t2, 1); + + /* select between the two cases */ + tcg_gen_movi_i32(t0, 0); + tcg_gen_movcond_i32(TCG_COND_GE, REG(B11_8), REG(B7_4), t0, t1, t2); + + tcg_temp_free(t0); + tcg_temp_free(t1); + tcg_temp_free(t2); } return; case 0x400d: /* shld Rm,Rn */ |