[PING] [PATCH] RISC-V: fix FRM register display mask value

[Hugues de Lassus <hugues.delassus@sifive.com>]

Ping.

On Mon, Jul 11, 2022 at 10:58 AM Hugues de Lassus <
hugues.delassus@sifive.com> wrote:

> The FRM register is 3-bit long, but the top-most bit was masked off for
> display, resulting in incorrectly displayed values and format strings
> when FRM >= 4.
>
> Tested on riscv64-unknown-linux-gnu target, with FPU support.
> ---
>  gdb/riscv-tdep.c                 | 2 +-
>  gdb/testsuite/gdb.base/float.exp | 4 +++-
>  2 files changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c
> index 69f2123dcdb..a3afab3b998 100644
> --- a/gdb/riscv-tdep.c
> +++ b/gdb/riscv-tdep.c
> @@ -1185,7 +1185,7 @@ riscv_print_one_register_info (struct gdbarch
> *gdbarch,
>                       "dynamic rounding mode",
>                     };
>                   int frm = ((regnum == RISCV_CSR_FCSR_REGNUM)
> -                            ? (d >> 5) : d) & 0x3;
> +                            ? (d >> 5) : d) & 0x7;
>
>                   gdb_printf (file, "%sFRM:%i [%s]",
>                               (regnum == RISCV_CSR_FCSR_REGNUM
> diff --git a/gdb/testsuite/gdb.base/float.exp
> b/gdb/testsuite/gdb.base/float.exp
> index 62e8346928b..10c0692a976 100644
> --- a/gdb/testsuite/gdb.base/float.exp
> +++ b/gdb/testsuite/gdb.base/float.exp
> @@ -112,14 +112,16 @@ if { [is_aarch64_target] } then {
>      gdb_test "info float" "f0.*f1.*f31.*d0.*d30.*" "info float"
>  } elseif [istarget "riscv*-*-*"] then {
>      # RISC-V may or may not have an FPU
> +    send_gdb "set \$frm = 7\n"
>      gdb_test_multiple "info float" "info float" {
> -       -re "ft0.*ft1.*ft11.*fflags.*frm.*fcsr.*$gdb_prompt $" {
> +       -re "ft0.*ft1.*ft11.*fflags.*frm.*0x7.*FRM:7.*fcsr.*$gdb_prompt $"
> {
>               pass "info float (with FPU)"
>           }
>         -re "No floating.point info available for this
> processor.*$gdb_prompt $" {
>               pass "info float (without FPU)"
>         }
>      }
> +    send_gdb "set \$frm = 0\n"
>  } else {
>      gdb_test "info float" "No floating.point info available for this
> processor." "info float (unknown target)"
>  }
> --
> 2.35.1
>
>