On 09/03/2015 02:17 AM, Richard Henderson wrote:
+
+void HELPER(ove)(CPUOpenRISCState *env, target_ulong test)
+{
+ if (unlikely(test) && (env->sr & SR_OVE)) {
+ OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
+ CPUState *cs = CPU(cpu);
+
+ cs->exception_index = EXCP_RANGE;
+ cpu_restore_state(cs, GETPC());
+ cpu_loop_exit(cs);
+ }
+}
You forgot to check the AECR register, whether the exception really occurs.
+static void gen_ove_cy(DisasContext *dc, TCGv cy)
+{
+ gen_helper_ove(cpu_env, cy);
+}
+
+static void gen_ove_ov(DisasContext *dc, TCGv ov)
+{
+ gen_helper_ove(cpu_env, ov);
+}
+
Do we really need two functions here? They differ only by the name of
the second argument. We should directly use gen_helper_ove ().
+static void gen_add(DisasContext *dc, TCGv dest, TCGv srca, TCGv srcb)
+{
+ TCGv t0 = tcg_const_tl(0);
+ TCGv res = tcg_temp_new();
+ TCGv sr_cy = tcg_temp_new();
+ TCGv sr_ov = tcg_temp_new();
+
+ tcg_gen_add2_tl(res, sr_cy, srca, t0, srcb, t0);
+ tcg_gen_xor_tl(sr_ov, srca, srcb);
+ tcg_gen_xor_tl(t0, res, srcb);
+ tcg_gen_andc_tl(sr_ov, t0, sr_ov);
+ tcg_temp_free(t0);
+
+ tcg_gen_mov_tl(dest, res);
+ tcg_temp_free(res);
+
+ tcg_gen_shri_tl(sr_ov, sr_ov, TARGET_LONG_BITS - 1);
+ tcg_gen_deposit_tl(cpu_sr, cpu_sr, sr_cy, ctz32(SR_CY), 1);
+ tcg_gen_deposit_tl(cpu_sr, cpu_sr, sr_ov, ctz32(SR_OV), 1);
+
+ gen_ove_cyov(dc, sr_ov, sr_cy);
+ tcg_temp_free(sr_ov);
+ tcg_temp_free(sr_cy);
+}
I do wonder, if we should use TCG globals for sr_cy and sr_ov, as you
recommended for the TriCore target. It would not change the helper in
case of no ovf/carry, but simplify addc. And we would not need two
deposits for every add/sub.
- if (ra != 0 && rb != 0) {
- gen_helper_mul32(cpu_R[rd], cpu_env, cpu_R[ra], cpu_R[rb]);
- } else {
- tcg_gen_movi_tl(cpu_R[rd], 0x0);
- }
+ gen_mul(dc, cpu_R[rd], cpu_R[ra], cpu_R[rb]);
What happened to this special case here? r0 should always hold zero, so
we can keep this optimization here, or at least move it to gen_mul().
- if (rb != 0 && ra != 0) {
- TCGv_i64 result = tcg_temp_local_new_i64();
- TCGv_i64 tra = tcg_temp_local_new_i64();
- TCGv_i64 trb = tcg_temp_local_new_i64();
- TCGv_i64 high = tcg_temp_new_i64();
- TCGv_i32 sr_ove = tcg_temp_local_new_i32();
- TCGLabel *lab = gen_new_label();
- /* Calculate each result. */
- tcg_gen_extu_i32_i64(tra, cpu_R[ra]);
- tcg_gen_extu_i32_i64(trb, cpu_R[rb]);
- tcg_gen_mul_i64(result, tra, trb);
- tcg_temp_free_i64(tra);
- tcg_temp_free_i64(trb);
- tcg_gen_shri_i64(high, result, TARGET_LONG_BITS);
- /* Overflow or not. */
- tcg_gen_brcondi_i64(TCG_COND_EQ, high, 0x00000000, lab);
- tcg_gen_ori_tl(cpu_sr, cpu_sr, (SR_OV | SR_CY));
- tcg_gen_andi_tl(sr_ove, cpu_sr, SR_OVE);
- tcg_gen_brcondi_tl(TCG_COND_NE, sr_ove, SR_OVE, lab);
- gen_exception(dc, EXCP_RANGE);
- gen_set_label(lab);
- tcg_temp_free_i64(high);
- tcg_gen_trunc_i64_tl(cpu_R[rd], result);
- tcg_temp_free_i64(result);
- tcg_temp_free_i32(sr_ove);
- } else {
- tcg_gen_movi_tl(cpu_R[rd], 0);
- }
+ gen_mulu(dc, cpu_R[rd], cpu_R[ra], cpu_R[rb]);
break;
The same here.
- {
- if (I16 == 0) {
- tcg_gen_mov_tl(cpu_R[rd], cpu_R[ra]);
- } else {
- TCGLabel *lab = gen_new_label();
- TCGv_i64 ta = tcg_temp_new_i64();
- TCGv_i64 td = tcg_temp_local_new_i64();
- TCGv_i32 res = tcg_temp_local_new_i32();
- TCGv_i32 sr_ove = tcg_temp_local_new_i32();
- tcg_gen_extu_i32_i64(ta, cpu_R[ra]);
- tcg_gen_addi_i64(td, ta, sign_extend(I16, 16));
- tcg_gen_extrl_i64_i32(res, td);
- tcg_gen_shri_i64(td, td, 32);
- tcg_gen_andi_i64(td, td, 0x3);
- /* Jump to lab when no overflow. */
- tcg_gen_brcondi_i64(TCG_COND_EQ, td, 0x0, lab);
- tcg_gen_brcondi_i64(TCG_COND_EQ, td, 0x3, lab);
- tcg_gen_ori_i32(cpu_sr, cpu_sr, (SR_OV | SR_CY));
- tcg_gen_andi_i32(sr_ove, cpu_sr, SR_OVE);
- tcg_gen_brcondi_i32(TCG_COND_NE, sr_ove, SR_OVE, lab);
- gen_exception(dc, EXCP_RANGE);
- gen_set_label(lab);
- tcg_gen_mov_i32(cpu_R[rd], res);
- tcg_temp_free_i64(ta);
- tcg_temp_free_i64(td);
- tcg_temp_free_i32(res);
- tcg_temp_free_i32(sr_ove);
- }
- }
+ t0 = tcg_const_tl(I16);
+ gen_add(dc, cpu_R[rd], cpu_R[ra], t0);
+ tcg_temp_free(t0);
break;
Again, why remove the special case?
case 0x29: /* l.andi */
@@ -963,13 +895,9 @@ static void dec_misc(DisasContext *dc, uint32_t insn)
case 0x2c: /* l.muli */
LOG_DIS("l.muli r%d, r%d, %d\n", rd, ra, I16);
- if (ra != 0 && I16 != 0) {
- TCGv_i32 im = tcg_const_i32(I16);
- gen_helper_mul32(cpu_R[rd], cpu_env, cpu_R[ra], im);
- tcg_temp_free_i32(im);
- } else {
- tcg_gen_movi_tl(cpu_R[rd], 0x0);
- }
+ t0 = tcg_const_tl(I16);
+ gen_mul(dc, cpu_R[rd], cpu_R[ra], t0);
+ tcg_temp_free(t0);
Again, why remove the special case?
Cheers,
Bastian
