[PATCH v2.5 3/3] xen/types: Rework stdint vs __{u,s}$N types

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

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 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 very old x86 compilers, synthesize
suitable types using GCC internals.

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>

v2.5:
 * Get the #ifdef-ary the right way around
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..8c8a5899373a
--- /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 */
+
+/*
+ * 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;
+
+#else
+
+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;
+
+#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;
-- 
2.30.2