Re: [PATCH v2 3/3] xen/types: Rework stdint vs __{u,s}$N types

[Oleksii <oleksii.kurochko@xxxxxxxxx>]

Reviewed-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>

On Tue, 2023-06-27 at 08:56 +0100, Andrew Cooper wrote:
> Xen uses the stdint types.  Rearrange the types headers to define the
> compatibility __{u,s}$N types in terms of the stdint types, not the
> other way
> around.
> 
> All all supported compilers on architectures other than x86 support
> the stdint
> __*_TYPE__ macros.  Move these into a new xen/stdint.h to avoid them
> being
> duplicated in each architecture.
> 
> For the compilers which don't support the __*_TYPE__ macros,
> synthesize
> appropriate alternatives.
> 
> This cleanup has the side effect of removing all use of the
> undocumented
> __signed__ GCC keyword.  This is a vestigial remnant of `gcc -
> traditional`
> mode for dialetcs of C prior to the introduction of the signed
> keyword.
> 
> No functional change.
> 
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> ---
> CC: Jan Beulich <JBeulich@xxxxxxxx>
> CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
> CC: Wei Liu <wl@xxxxxxx>
> CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
> CC: Julien Grall <julien@xxxxxxx>
> CC: Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>
> CC: Bertrand Marquis <bertrand.marquis@xxxxxxx>
> CC: Bob Eshleman <bobbyeshleman@xxxxxxxxx>
> CC: Alistair Francis <alistair.francis@xxxxxxx>
> CC: Connor Davis <connojdavis@xxxxxxxxx>
> CC: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> CC: Shawn Anastasio <sanastasio@xxxxxxxxxxxxxxxxxxxxx>
> CC: Timothy Pearson <tpearson@xxxxxxxxxxxxxxxxxxxxx>
> CC: Roberto Bagnara <roberto.bagnara@xxxxxxxxxxx>
> 
> v2:
>  * Introduce xen/stdint.h as discussed at XenSummit
> ---
>  xen/arch/arm/include/asm/types.h   | 19 -----------------
>  xen/arch/riscv/include/asm/types.h | 19 -----------------
>  xen/arch/x86/include/asm/types.h   | 14 -------------
>  xen/include/xen/stdint.h           | 33
> ++++++++++++++++++++++++++++++
>  xen/include/xen/types.h            | 20 ++++++++----------
>  5 files changed, 42 insertions(+), 63 deletions(-)
>  create mode 100644 xen/include/xen/stdint.h
> 
> diff --git a/xen/arch/arm/include/asm/types.h
> b/xen/arch/arm/include/asm/types.h
> index fb6618ef247f..545a5e9d1175 100644
> --- a/xen/arch/arm/include/asm/types.h
> +++ b/xen/arch/arm/include/asm/types.h
> @@ -1,25 +1,6 @@
>  #ifndef __ARM_TYPES_H__
>  #define __ARM_TYPES_H__
>  
> -typedef __signed__ char __s8;
> -typedef unsigned char __u8;
> -
> -typedef __signed__ short __s16;
> -typedef unsigned short __u16;
> -
> -typedef __signed__ int __s32;
> -typedef unsigned int __u32;
> -
> -#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
> -#if defined(CONFIG_ARM_32)
> -typedef __signed__ long long __s64;
> -typedef unsigned long long __u64;
> -#elif defined (CONFIG_ARM_64)
> -typedef __signed__ long __s64;
> -typedef unsigned long __u64;
> -#endif
> -#endif
> -
>  typedef signed char s8;
>  typedef unsigned char u8;
>  
> diff --git a/xen/arch/riscv/include/asm/types.h
> b/xen/arch/riscv/include/asm/types.h
> index 0c0ce78c8f6e..93a680a8f323 100644
> --- a/xen/arch/riscv/include/asm/types.h
> +++ b/xen/arch/riscv/include/asm/types.h
> @@ -1,25 +1,6 @@
>  #ifndef __RISCV_TYPES_H__
>  #define __RISCV_TYPES_H__
>  
> -typedef __signed__ char __s8;
> -typedef unsigned char __u8;
> -
> -typedef __signed__ short __s16;
> -typedef unsigned short __u16;
> -
> -typedef __signed__ int __s32;
> -typedef unsigned int __u32;
> -
> -#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
> -#if defined(CONFIG_RISCV_32)
> -typedef __signed__ long long __s64;
> -typedef unsigned long long __u64;
> -#elif defined (CONFIG_RISCV_64)
> -typedef __signed__ long __s64;
> -typedef unsigned long __u64;
> -#endif
> -#endif
> -
>  typedef signed char s8;
>  typedef unsigned char u8;
>  
> diff --git a/xen/arch/x86/include/asm/types.h
> b/xen/arch/x86/include/asm/types.h
> index 2d56aed66782..c9d257716551 100644
> --- a/xen/arch/x86/include/asm/types.h
> +++ b/xen/arch/x86/include/asm/types.h
> @@ -1,20 +1,6 @@
>  #ifndef __X86_TYPES_H__
>  #define __X86_TYPES_H__
>  
> -typedef __signed__ char __s8;
> -typedef unsigned char __u8;
> -
> -typedef __signed__ short __s16;
> -typedef unsigned short __u16;
> -
> -typedef __signed__ int __s32;
> -typedef unsigned int __u32;
> -
> -#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
> -typedef __signed__ long __s64;
> -typedef unsigned long __u64;
> -#endif
> -
>  typedef signed char s8;
>  typedef unsigned char u8;
>  
> diff --git a/xen/include/xen/stdint.h b/xen/include/xen/stdint.h
> new file mode 100644
> index 000000000000..4cf82790f196
> --- /dev/null
> +++ b/xen/include/xen/stdint.h
> @@ -0,0 +1,33 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +#ifndef __XEN_STDINT_H__
> +#define __XEN_STDINT_H__
> +
> +#ifndef __INT8_TYPE__ /* GCC <= 4.4 */
> +
> +typedef __INT8_TYPE__        int8_t;
> +typedef __UINT8_TYPE__      uint8_t;
> +typedef __INT16_TYPE__      int16_t;
> +typedef __UINT16_TYPE__    uint16_t;
> +typedef __INT32_TYPE__      int32_t;
> +typedef __UINT32_TYPE__    uint32_t;
> +typedef __INT64_TYPE__      int64_t;
> +typedef __UINT64_TYPE__    uint64_t;
> +
> +#else
> +
> +/*
> + * Define the types using GCC internal notation.  Clang understands
> this too.
> + *
> https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html
> + */
> +typedef   signed __attribute__((__mode__(QI)))     int8_t;
> +typedef unsigned __attribute__((__mode__(QI)))    uint8_t;
> +typedef   signed __attribute__((__mode__(HI)))    int16_t;
> +typedef unsigned __attribute__((__mode__(HI)))   uint16_t;
> +typedef   signed __attribute__((__mode__(SI)))    int32_t;
> +typedef unsigned __attribute__((__mode__(SI)))   uint32_t;
> +typedef   signed __attribute__((__mode__(DI)))    int64_t;
> +typedef unsigned __attribute__((__mode__(DI)))   uint64_t;
> +
> +#endif
> +
> +#endif /* __XEN_STDINT_H__ */
> diff --git a/xen/include/xen/types.h b/xen/include/xen/types.h
> index 8b22a02eeaa4..c873c81ccf06 100644
> --- a/xen/include/xen/types.h
> +++ b/xen/include/xen/types.h
> @@ -2,6 +2,7 @@
>  #define __TYPES_H__
>  
>  #include <xen/stdbool.h>
> +#include <xen/stdint.h>
>  
>  #include <asm/types.h>
>  
> @@ -39,17 +40,14 @@ typedef __PTRDIFF_TYPE__ ptrdiff_t;
>  #define LONG_MIN        (-LONG_MAX - 1)
>  #define ULONG_MAX       (~0UL)
>  
> -typedef         __u8            uint8_t;
> -typedef         __s8            int8_t;
> -
> -typedef         __u16           uint16_t;
> -typedef         __s16           int16_t;
> -
> -typedef         __u32           uint32_t;
> -typedef         __s32           int32_t;
> -
> -typedef         __u64           uint64_t;
> -typedef         __s64           int64_t;
> +typedef uint8_t         __u8;
> +typedef int8_t          __s8;
> +typedef uint16_t        __u16;
> +typedef int16_t         __s16;
> +typedef uint32_t        __u32;
> +typedef int32_t         __s32;
> +typedef uint64_t        __u64;
> +typedef int64_t         __s64;
>  
>  typedef __u16 __le16;
>  typedef __u16 __be16;