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[PATCH-for-10.1 v7 6/8] gdbstub/helpers: Replace TARGET_BIG_ENDIAN -> target_big_endian()

Philippe Mathieu-Daudé posted 8 patches 5 months, 1 week ago
Maintainers: Richard Henderson <richard.henderson@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, "Michael S. Tsirkin" <mst@redhat.com>, Igor Mammedov <imammedo@redhat.com>, Ani Sinha <anisinha@redhat.com>, Beniamino Galvani <b.galvani@gmail.com>, Peter Maydell <peter.maydell@linaro.org>, Strahinja Jankovic <strahinja.p.jankovic@gmail.com>, Tyrone Ting <kfting@nuvoton.com>, Hao Wu <wuhaotsh@google.com>, John Snow <jsnow@redhat.com>, Kevin Wolf <kwolf@redhat.com>, Hanna Reitz <hreitz@redhat.com>, Palmer Dabbelt <palmer@dabbelt.com>, Alistair Francis <alistair.francis@wdc.com>, Weiwei Li <liwei1518@gmail.com>, Daniel Henrique Barboza <dbarboza@ventanamicro.com>, Liu Zhiwei <zhiwei_liu@linux.alibaba.com>, "Marc-André Lureau" <marcandre.lureau@redhat.com>, Eduardo Habkost <eduardo@habkost.net>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Yanan Wang <wangyanan55@huawei.com>, Zhao Liu <zhao1.liu@intel.com>, Jonathan Cameron <jonathan.cameron@huawei.com>, Fan Ni <fan.ni@samsung.com>, Helge Deller <deller@gmx.de>, Gerd Hoffmann <kraxel@redhat.com>, Pavel Pisa <pisa@cmp.felk.cvut.cz>, Francisco Iglesias <francisco.iglesias@amd.com>, Vikram Garhwal <vikram.garhwal@bytedance.com>, Jason Wang <jasowang@redhat.com>, Dmitry Fleytman <dmitry.fleytman@gmail.com>, Aurelien Jarno <aurelien@aurel32.net>, Nicholas Piggin <npiggin@gmail.com>, "Frédéric Barrat" <fbarrat@linux.ibm.com>, Bernhard Beschow <shentey@gmail.com>, Yoshinori Sato <yoshinori.sato@nifty.com>, Magnus Damm <magnus.damm@gmail.com>, Matthew Rosato <mjrosato@linux.ibm.com>, Eric Farman <farman@linux.ibm.com>, Halil Pasic <pasic@linux.ibm.com>, Christian Borntraeger <borntraeger@linux.ibm.com>, Thomas Huth <thuth@redhat.com>, David Hildenbrand <david@redhat.com>, Ilya Leoshkevich <iii@linux.ibm.com>, Alex Williamson <alex.williamson@redhat.com>, "Cédric Le Goater" <clg@redhat.com>, Alexander Graf <agraf@csgraf.de>, Phil Dennis-Jordan <phil@philjordan.eu>, "Alex Bennée" <alex.bennee@linaro.org>, Pierrick Bouvier <pierrick.bouvier@linaro.org>, Peter Xu <peterx@redhat.com>, Riku Voipio <riku.voipio@iki.fi>, Fabiano Rosas <farosas@suse.de>, Laurent Vivier <lvivier@redhat.com>, Song Gao <gaosong@loongson.cn>, Huacai Chen <chenhuacai@kernel.org>, Jiaxun Yang <jiaxun.yang@flygoat.com>, Aleksandar Rikalo <arikalo@gmail.com>, Alexandre Iooss <erdnaxe@crans.org>, Mahmoud Mandour <ma.mandourr@gmail.com>
There is a newer version of this series
[PATCH-for-10.1 v7 6/8] gdbstub/helpers: Replace TARGET_BIG_ENDIAN -> target_big_endian()
Posted by Philippe Mathieu-Daudé 5 months, 1 week ago 
Check endianness at runtime to remove the target-specific
TARGET_BIG_ENDIAN definition.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 include/gdbstub/helpers.h | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/include/gdbstub/helpers.h b/include/gdbstub/helpers.h
index 6f7cc48adcb..1411b136d5c 100644
--- a/include/gdbstub/helpers.h
+++ b/include/gdbstub/helpers.h
@@ -16,6 +16,7 @@
 #error "gdbstub helpers should only be included by target specific code"
 #endif
 
+#include "qemu/target-info.h"
 #include "exec/tswap.h"
 #include "cpu-param.h"
 
@@ -55,18 +56,14 @@ static inline int gdb_get_reg64(GByteArray *buf, uint64_t val)
 static inline int gdb_get_reg128(GByteArray *buf, uint64_t val_hi,
                                  uint64_t val_lo)
 {
+    bool be = target_big_endian();
     uint64_t to_quad;
-#if TARGET_BIG_ENDIAN
-    to_quad = tswap64(val_hi);
+
+    to_quad = tswap64(be ? val_hi : val_lo);
     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
-    to_quad = tswap64(val_lo);
+    to_quad = tswap64(be ? val_lo : val_hi);
     g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
-#else
-    to_quad = tswap64(val_lo);
-    g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
-    to_quad = tswap64(val_hi);
-    g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
-#endif
+
     return 16;
 }
 
-- 
2.49.0
Re: [PATCH-for-10.1 v7 6/8] gdbstub/helpers: Replace TARGET_BIG_ENDIAN -> target_big_endian()
Posted by Pierrick Bouvier 5 months, 1 week ago 
On 7/8/25 10:19 AM, Philippe Mathieu-Daudé wrote:
> Check endianness at runtime to remove the target-specific
> TARGET_BIG_ENDIAN definition.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   include/gdbstub/helpers.h | 15 ++++++---------
>   1 file changed, 6 insertions(+), 9 deletions(-)

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Re: [PATCH-for-10.1 v7 6/8] gdbstub/helpers: Replace TARGET_BIG_ENDIAN -> target_big_endian()
Posted by Richard Henderson 5 months, 1 week ago 
On 7/8/25 11:19, Philippe Mathieu-Daudé wrote:
> Check endianness at runtime to remove the target-specific
> TARGET_BIG_ENDIAN definition.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   include/gdbstub/helpers.h | 15 ++++++---------
>   1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/include/gdbstub/helpers.h b/include/gdbstub/helpers.h
> index 6f7cc48adcb..1411b136d5c 100644
> --- a/include/gdbstub/helpers.h
> +++ b/include/gdbstub/helpers.h
> @@ -16,6 +16,7 @@
>   #error "gdbstub helpers should only be included by target specific code"
>   #endif
>   
> +#include "qemu/target-info.h"
>   #include "exec/tswap.h"
>   #include "cpu-param.h"
>   
> @@ -55,18 +56,14 @@ static inline int gdb_get_reg64(GByteArray *buf, uint64_t val)
>   static inline int gdb_get_reg128(GByteArray *buf, uint64_t val_hi,
>                                    uint64_t val_lo)
>   {
> +    bool be = target_big_endian();
>       uint64_t to_quad;
> -#if TARGET_BIG_ENDIAN
> -    to_quad = tswap64(val_hi);
> +
> +    to_quad = tswap64(be ? val_hi : val_lo);
>       g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
> -    to_quad = tswap64(val_lo);
> +    to_quad = tswap64(be ? val_lo : val_hi);
>       g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
> -#else
> -    to_quad = tswap64(val_lo);
> -    g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
> -    to_quad = tswap64(val_hi);
> -    g_byte_array_append(buf, (uint8_t *) &to_quad, 8);
> -#endif

Don't split the endianness check between here and also within tswap64.

This would be much better as

     uint64_t tmp[2];
     if (target_big_endian()) {
         tmp[0] = cpu_to_be64(val_hi);
         tmp[1] = cpu_to_be64(val_lo);
     } else {
         tmp[0] = cpu_to_le64(val_lo);
         tmp[1] = cpu_to_le64(val_hi);
     }
     g_byte_array_append(buf, (uint8_t *)&tmp, 16);


r~

Patchew 2.1-devel-b67e4c2

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