First round of target/i386/tcg patches for QEMU 11.0

[PATCH 11/18] target/i386/tcg: reuse gen_helper_fp_arith_ST0_FT0 for fcom STn and fcomp STn

Posted by Paolo Bonzini 6 days, 14 hours ago

Treat specially the undocumented ops, instead of treating specially the
two d8/0 opcodes that have undocumented variants: just call
gen_helper_fp_arith_ST0_FT0 for all opcodes in the d8/0 encoding.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/tcg/translate.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index 3c55b62bdec..8f50071a4f4 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -2777,7 +2777,7 @@ static void gen_x87(DisasContext *s, X86DecodedInsn *decode)
                 break;
             }
             break;
-        case 0x00: case 0x01: case 0x04 ... 0x07: /* fxxx st, sti */
+        case 0x00 ... 0x07: /* fxxx st, sti */
             gen_helper_fmov_FT0_STN(tcg_env,
                                     tcg_constant_i32(opreg));
             gen_helper_fp_arith_ST0_FT0(op & 7);
@@ -2790,12 +2790,10 @@ static void gen_x87(DisasContext *s, X86DecodedInsn *decode)
                 gen_helper_fpop(tcg_env);
             }
             break;
-        case 0x02: /* fcom */
         case 0x22: /* fcom2, undocumented op */
             gen_helper_fmov_FT0_STN(tcg_env, tcg_constant_i32(opreg));
             gen_helper_fcom_ST0_FT0(tcg_env);
             break;
-        case 0x03: /* fcomp */
         case 0x23: /* fcomp3, undocumented op */
         case 0x32: /* fcomp5, undocumented op */
             gen_helper_fmov_FT0_STN(tcg_env, tcg_constant_i32(opreg));
-- 
2.52.0

Re: [PATCH 11/18] target/i386/tcg: reuse gen_helper_fp_arith_ST0_FT0 for fcom STn and fcomp STn

Posted by Richard Henderson 5 days, 11 hours ago

On 12/10/25 07:16, Paolo Bonzini wrote:
> Treat specially the undocumented ops, instead of treating specially the
> two d8/0 opcodes that have undocumented variants: just call
> gen_helper_fp_arith_ST0_FT0 for all opcodes in the d8/0 encoding.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>   target/i386/tcg/translate.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
> index 3c55b62bdec..8f50071a4f4 100644
> --- a/target/i386/tcg/translate.c
> +++ b/target/i386/tcg/translate.c
> @@ -2777,7 +2777,7 @@ static void gen_x87(DisasContext *s, X86DecodedInsn *decode)
>                   break;
>               }
>               break;
> -        case 0x00: case 0x01: case 0x04 ... 0x07: /* fxxx st, sti */
> +        case 0x00 ... 0x07: /* fxxx st, sti */
>               gen_helper_fmov_FT0_STN(tcg_env,
>                                       tcg_constant_i32(opreg));
>               gen_helper_fp_arith_ST0_FT0(op & 7);
> @@ -2790,12 +2790,10 @@ static void gen_x87(DisasContext *s, X86DecodedInsn *decode)
>                   gen_helper_fpop(tcg_env);
>               }
>               break;
> -        case 0x02: /* fcom */
>           case 0x22: /* fcom2, undocumented op */
>               gen_helper_fmov_FT0_STN(tcg_env, tcg_constant_i32(opreg));
>               gen_helper_fcom_ST0_FT0(tcg_env);
>               break;
> -        case 0x03: /* fcomp */
>           case 0x23: /* fcomp3, undocumented op */
>           case 0x32: /* fcomp5, undocumented op */
>               gen_helper_fmov_FT0_STN(tcg_env, tcg_constant_i32(opreg));

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

r~