diff mbox series

[v2,05/14] target/arm: Implement FMOV (general) for fp16

Message ID 20180502221552.3873-6-richard.henderson@linaro.org
State Superseded
Headers show
Series target/arm: Fixups for ARM_FEATURE_V8_FP16 | expand

Commit Message

Richard Henderson May 2, 2018, 10:15 p.m. UTC
Adding the fp16 moves to/from general registers.

Cc: qemu-stable@nongnu.org
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

---
 target/arm/translate-a64.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

-- 
2.14.3

Comments

Peter Maydell May 10, 2018, 4:21 p.m. UTC | #1
On 2 May 2018 at 23:15, Richard Henderson <richard.henderson@linaro.org> wrote:
> Adding the fp16 moves to/from general registers.

>

> Cc: qemu-stable@nongnu.org

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

> ---

>  target/arm/translate-a64.c | 22 +++++++++++++++++++++-

>  1 file changed, 21 insertions(+), 1 deletion(-)

>

> diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c

> index c64c3ed99d..247a4f0cce 100644

> --- a/target/arm/translate-a64.c

> +++ b/target/arm/translate-a64.c

> @@ -5463,6 +5463,15 @@ static void handle_fmov(DisasContext *s, int rd, int rn, int type, bool itof)

>              tcg_gen_st_i64(tcg_rn, cpu_env, fp_reg_hi_offset(s, rd));

>              clear_vec_high(s, true, rd);

>              break;

> +        case 3:

> +            /* 16 bit */

> +            tmp = tcg_temp_new_i64();

> +            tcg_gen_ext16u_i64(tmp, tcg_rn);

> +            write_fp_dreg(s, rd, tmp);

> +            tcg_temp_free_i64(tmp);

> +            break;

> +        default:

> +            g_assert_not_reached();

>          }

>      } else {

>          TCGv_i64 tcg_rd = cpu_reg(s, rd);

> @@ -5480,6 +5489,12 @@ static void handle_fmov(DisasContext *s, int rd, int rn, int type, bool itof)

>              /* 64 bits from top half */

>              tcg_gen_ld_i64(tcg_rd, cpu_env, fp_reg_hi_offset(s, rn));

>              break;

> +        case 3:

> +            /* 16 bit */

> +            tcg_gen_ld16u_i64(tcg_rd, cpu_env, fp_reg_offset(s, rn, MO_16));

> +            break;

> +        default:

> +            g_assert_not_reached();

>          }

>      }

>  }

> @@ -5519,10 +5534,15 @@ static void disas_fp_int_conv(DisasContext *s, uint32_t insn)

>          case 0xa: /* 64 bit */

>          case 0xd: /* 64 bit to top half of quad */

>              break;

> +        case 0x6: /* 16-bit */

> +            if (arm_dc_feature(s, ARM_FEATURE_V8_FP16)) {

> +                break;

> +            }

> +            /* fallthru */


This is a switch on (sf << 3 | type << 1 | rmode), so this catches
the halfprec <-> 32 bit cases, but it misses the halfprec <-> 64 bit
ops, which have sf == 1. So I think you need a 'case 0xe' as well.

>          default:

>              /* all other sf/type/rmode combinations are invalid */

>              unallocated_encoding(s);

> -            break;

> +            return;


This is a distinct bugfix, I think (though the only effect would
be generation of unnecessary dead code after the undef).

>          }

>

>          if (!fp_access_check(s)) {

> --

> 2.14.3


thanks
-- PMM
diff mbox series

Patch

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index c64c3ed99d..247a4f0cce 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -5463,6 +5463,15 @@  static void handle_fmov(DisasContext *s, int rd, int rn, int type, bool itof)
             tcg_gen_st_i64(tcg_rn, cpu_env, fp_reg_hi_offset(s, rd));
             clear_vec_high(s, true, rd);
             break;
+        case 3:
+            /* 16 bit */
+            tmp = tcg_temp_new_i64();
+            tcg_gen_ext16u_i64(tmp, tcg_rn);
+            write_fp_dreg(s, rd, tmp);
+            tcg_temp_free_i64(tmp);
+            break;
+        default:
+            g_assert_not_reached();
         }
     } else {
         TCGv_i64 tcg_rd = cpu_reg(s, rd);
@@ -5480,6 +5489,12 @@  static void handle_fmov(DisasContext *s, int rd, int rn, int type, bool itof)
             /* 64 bits from top half */
             tcg_gen_ld_i64(tcg_rd, cpu_env, fp_reg_hi_offset(s, rn));
             break;
+        case 3:
+            /* 16 bit */
+            tcg_gen_ld16u_i64(tcg_rd, cpu_env, fp_reg_offset(s, rn, MO_16));
+            break;
+        default:
+            g_assert_not_reached();
         }
     }
 }
@@ -5519,10 +5534,15 @@  static void disas_fp_int_conv(DisasContext *s, uint32_t insn)
         case 0xa: /* 64 bit */
         case 0xd: /* 64 bit to top half of quad */
             break;
+        case 0x6: /* 16-bit */
+            if (arm_dc_feature(s, ARM_FEATURE_V8_FP16)) {
+                break;
+            }
+            /* fallthru */
         default:
             /* all other sf/type/rmode combinations are invalid */
             unallocated_encoding(s);
-            break;
+            return;
         }
 
         if (!fp_access_check(s)) {