diff mbox series

[2/4] target/openrisc: Use tcg_constant_tl for dc->R0

Message ID 20210708213754.830485-3-richard.henderson@linaro.org
State Superseded
Headers show
Series target/openrisc: Use tcg_constant_* | expand

Commit Message

Richard Henderson July 8, 2021, 9:37 p.m. UTC 
The temp allocated for tcg_const_tl is auto-freed at branches,
but pure constants are not.  So we can remove the extra hoop
jumping in trans_l_swa.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

---
 target/openrisc/translate.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

-- 
2.25.1

Comments

Stafford Horne July 10, 2021, 12:11 p.m. UTC | #1 
On Thu, Jul 08, 2021 at 02:37:52PM -0700, Richard Henderson wrote:
> The temp allocated for tcg_const_tl is auto-freed at branches,

> but pure constants are not.  So we can remove the extra hoop

> jumping in trans_l_swa.


This is nice.

> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>


Reviewed-by: Stafford Horne <shorne@gmail.com>
diff mbox series

Patch

diff --git a/target/openrisc/translate.c b/target/openrisc/translate.c
index 1e437d2f9d..96df513fd3 100644
--- a/target/openrisc/translate.c
+++ b/target/openrisc/translate.c
@@ -733,12 +733,6 @@  static bool trans_l_swa(DisasContext *dc, arg_store *a)
     ea = tcg_temp_new();
     tcg_gen_addi_tl(ea, cpu_R(dc, a->a), a->i);
 
-    /* For TB_FLAGS_R0_0, the branch below invalidates the temporary assigned
-       to cpu_regs[0].  Since l.swa is quite often immediately followed by a
-       branch, don't bother reallocating; finish the TB using the "real" R0.
-       This also takes care of RB input across the branch.  */
-    dc->R0 = cpu_regs[0];
-
     lab_fail = gen_new_label();
     lab_done = gen_new_label();
     tcg_gen_brcond_tl(TCG_COND_NE, ea, cpu_lock_addr, lab_fail);
@@ -746,7 +740,7 @@  static bool trans_l_swa(DisasContext *dc, arg_store *a)
 
     val = tcg_temp_new();
     tcg_gen_atomic_cmpxchg_tl(val, cpu_lock_addr, cpu_lock_value,
-                              cpu_regs[a->b], dc->mem_idx, MO_TEUL);
+                              cpu_R(dc, a->b), dc->mem_idx, MO_TEUL);
     tcg_gen_setcond_tl(TCG_COND_EQ, cpu_sr_f, val, cpu_lock_value);
     tcg_temp_free(val);
 
@@ -1602,7 +1596,7 @@  static void openrisc_tr_tb_start(DisasContextBase *db, CPUState *cs)
     /* Allow the TCG optimizer to see that R0 == 0,
        when it's true, which is the common case.  */
     if (dc->tb_flags & TB_FLAGS_R0_0) {
-        dc->R0 = tcg_const_tl(0);
+        dc->R0 = tcg_constant_tl(0);
     } else {
         dc->R0 = cpu_regs[0];
     }