[RFC PATCH 1/3] tools/nolibc: merge i386 and x86_64 into a single x86 arch
From: Willy Tarreau
Date: Fri Jun 20 2025 - 06:39:29 EST
This remained the only exception to the kernel's architectures
organization and it's always a bit cumbersome to deal with. Let's merge
i386 and x86_64 into x86. This will result in a single arch-x86.h file
by default, and we'll no longer need to merge the two manually during
installation. Requesting either i386 or x86_64 will also result in
installing x86.
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
tools/include/nolibc/Makefile | 10 +-
tools/include/nolibc/arch-i386.h | 178 -----------------
.../nolibc/{arch-x86_64.h => arch-x86.h} | 180 +++++++++++++++++-
tools/include/nolibc/arch.h | 6 +-
4 files changed, 179 insertions(+), 195 deletions(-)
delete mode 100644 tools/include/nolibc/arch-i386.h
rename tools/include/nolibc/{arch-x86_64.h => arch-x86.h} (53%)
diff --git a/tools/include/nolibc/Makefile b/tools/include/nolibc/Makefile
index 823bfa08c6756..9197c79b267a4 100644
--- a/tools/include/nolibc/Makefile
+++ b/tools/include/nolibc/Makefile
@@ -93,18 +93,12 @@ help:
@echo " OUTPUT = $(OUTPUT)"
@echo ""
-# Note: when ARCH is "x86" we concatenate both x86_64 and i386
headers:
$(Q)mkdir -p $(OUTPUT)sysroot
$(Q)mkdir -p $(OUTPUT)sysroot/include
$(Q)cp --parents $(all_files) $(OUTPUT)sysroot/include/
- $(Q)if [ "$(ARCH)" = "x86" ]; then \
- sed -e \
- 's,^#ifndef _NOLIBC_ARCH_X86_64_H,#if !defined(_NOLIBC_ARCH_X86_64_H) \&\& defined(__x86_64__),' \
- arch-x86_64.h; \
- sed -e \
- 's,^#ifndef _NOLIBC_ARCH_I386_H,#if !defined(_NOLIBC_ARCH_I386_H) \&\& !defined(__x86_64__),' \
- arch-i386.h; \
+ $(Q)if [ "$(ARCH)" = "i386" -o "$(ARCH)" = "x86_64" ]; then \
+ cat arch-x86.h; \
elif [ -e "$(arch_file)" ]; then \
cat $(arch_file); \
else \
diff --git a/tools/include/nolibc/arch-i386.h b/tools/include/nolibc/arch-i386.h
deleted file mode 100644
index 7c9b38e964183..0000000000000
--- a/tools/include/nolibc/arch-i386.h
+++ /dev/null
@@ -1,178 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
-/*
- * i386 specific definitions for NOLIBC
- * Copyright (C) 2017-2022 Willy Tarreau <w@xxxxxx>
- */
-
-#ifndef _NOLIBC_ARCH_I386_H
-#define _NOLIBC_ARCH_I386_H
-
-#include "compiler.h"
-#include "crt.h"
-
-/* Syscalls for i386 :
- * - mostly similar to x86_64
- * - registers are 32-bit
- * - syscall number is passed in eax
- * - arguments are in ebx, ecx, edx, esi, edi, ebp respectively
- * - all registers are preserved (except eax of course)
- * - the system call is performed by calling int $0x80
- * - syscall return comes in eax
- * - the arguments are cast to long and assigned into the target registers
- * which are then simply passed as registers to the asm code, so that we
- * don't have to experience issues with register constraints.
- * - the syscall number is always specified last in order to allow to force
- * some registers before (gcc refuses a %-register at the last position).
- *
- * Also, i386 supports the old_select syscall if newselect is not available
- */
-#define __ARCH_WANT_SYS_OLD_SELECT
-
-#define my_syscall0(num) \
-({ \
- long _ret; \
- register long _num __asm__ ("eax") = (num); \
- \
- __asm__ volatile ( \
- "int $0x80\n" \
- : "=a" (_ret) \
- : "0"(_num) \
- : "memory", "cc" \
- ); \
- _ret; \
-})
-
-#define my_syscall1(num, arg1) \
-({ \
- long _ret; \
- register long _num __asm__ ("eax") = (num); \
- register long _arg1 __asm__ ("ebx") = (long)(arg1); \
- \
- __asm__ volatile ( \
- "int $0x80\n" \
- : "=a" (_ret) \
- : "r"(_arg1), \
- "0"(_num) \
- : "memory", "cc" \
- ); \
- _ret; \
-})
-
-#define my_syscall2(num, arg1, arg2) \
-({ \
- long _ret; \
- register long _num __asm__ ("eax") = (num); \
- register long _arg1 __asm__ ("ebx") = (long)(arg1); \
- register long _arg2 __asm__ ("ecx") = (long)(arg2); \
- \
- __asm__ volatile ( \
- "int $0x80\n" \
- : "=a" (_ret) \
- : "r"(_arg1), "r"(_arg2), \
- "0"(_num) \
- : "memory", "cc" \
- ); \
- _ret; \
-})
-
-#define my_syscall3(num, arg1, arg2, arg3) \
-({ \
- long _ret; \
- register long _num __asm__ ("eax") = (num); \
- register long _arg1 __asm__ ("ebx") = (long)(arg1); \
- register long _arg2 __asm__ ("ecx") = (long)(arg2); \
- register long _arg3 __asm__ ("edx") = (long)(arg3); \
- \
- __asm__ volatile ( \
- "int $0x80\n" \
- : "=a" (_ret) \
- : "r"(_arg1), "r"(_arg2), "r"(_arg3), \
- "0"(_num) \
- : "memory", "cc" \
- ); \
- _ret; \
-})
-
-#define my_syscall4(num, arg1, arg2, arg3, arg4) \
-({ \
- long _ret; \
- register long _num __asm__ ("eax") = (num); \
- register long _arg1 __asm__ ("ebx") = (long)(arg1); \
- register long _arg2 __asm__ ("ecx") = (long)(arg2); \
- register long _arg3 __asm__ ("edx") = (long)(arg3); \
- register long _arg4 __asm__ ("esi") = (long)(arg4); \
- \
- __asm__ volatile ( \
- "int $0x80\n" \
- : "=a" (_ret) \
- : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), \
- "0"(_num) \
- : "memory", "cc" \
- ); \
- _ret; \
-})
-
-#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \
-({ \
- long _ret; \
- register long _num __asm__ ("eax") = (num); \
- register long _arg1 __asm__ ("ebx") = (long)(arg1); \
- register long _arg2 __asm__ ("ecx") = (long)(arg2); \
- register long _arg3 __asm__ ("edx") = (long)(arg3); \
- register long _arg4 __asm__ ("esi") = (long)(arg4); \
- register long _arg5 __asm__ ("edi") = (long)(arg5); \
- \
- __asm__ volatile ( \
- "int $0x80\n" \
- : "=a" (_ret) \
- : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
- "0"(_num) \
- : "memory", "cc" \
- ); \
- _ret; \
-})
-
-#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \
-({ \
- long _eax = (long)(num); \
- long _arg6 = (long)(arg6); /* Always in memory */ \
- __asm__ volatile ( \
- "pushl %[_arg6]\n\t" \
- "pushl %%ebp\n\t" \
- "movl 4(%%esp),%%ebp\n\t" \
- "int $0x80\n\t" \
- "popl %%ebp\n\t" \
- "addl $4,%%esp\n\t" \
- : "+a"(_eax) /* %eax */ \
- : "b"(arg1), /* %ebx */ \
- "c"(arg2), /* %ecx */ \
- "d"(arg3), /* %edx */ \
- "S"(arg4), /* %esi */ \
- "D"(arg5), /* %edi */ \
- [_arg6]"m"(_arg6) /* memory */ \
- : "memory", "cc" \
- ); \
- _eax; \
-})
-
-/* startup code */
-/*
- * i386 System V ABI mandates:
- * 1) last pushed argument must be 16-byte aligned.
- * 2) The deepest stack frame should be set to zero
- *
- */
-void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
-{
- __asm__ volatile (
- "xor %ebp, %ebp\n" /* zero the stack frame */
- "mov %esp, %eax\n" /* save stack pointer to %eax, as arg1 of _start_c */
- "sub $12, %esp\n" /* sub 12 to keep it aligned after the push %eax */
- "push %eax\n" /* push arg1 on stack to support plain stack modes too */
- "call _start_c\n" /* transfer to c runtime */
- "hlt\n" /* ensure it does not return */
- );
- __nolibc_entrypoint_epilogue();
-}
-
-#endif /* _NOLIBC_ARCH_I386_H */
diff --git a/tools/include/nolibc/arch-x86_64.h b/tools/include/nolibc/arch-x86.h
similarity index 53%
rename from tools/include/nolibc/arch-x86_64.h
rename to tools/include/nolibc/arch-x86.h
index 67305e24dbefd..d3efc0c3b8adc 100644
--- a/tools/include/nolibc/arch-x86_64.h
+++ b/tools/include/nolibc/arch-x86.h
@@ -1,15 +1,184 @@
/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
/*
- * x86_64 specific definitions for NOLIBC
- * Copyright (C) 2017-2022 Willy Tarreau <w@xxxxxx>
+ * x86 specific definitions for NOLIBC (both 32- and 64-bit)
+ * Copyright (C) 2017-2025 Willy Tarreau <w@xxxxxx>
*/
-#ifndef _NOLIBC_ARCH_X86_64_H
-#define _NOLIBC_ARCH_X86_64_H
+#ifndef _NOLIBC_ARCH_X86_H
+#define _NOLIBC_ARCH_X86_H
#include "compiler.h"
#include "crt.h"
+#if !defined(__x86_64__)
+
+/* Syscalls for i386 :
+ * - mostly similar to x86_64
+ * - registers are 32-bit
+ * - syscall number is passed in eax
+ * - arguments are in ebx, ecx, edx, esi, edi, ebp respectively
+ * - all registers are preserved (except eax of course)
+ * - the system call is performed by calling int $0x80
+ * - syscall return comes in eax
+ * - the arguments are cast to long and assigned into the target registers
+ * which are then simply passed as registers to the asm code, so that we
+ * don't have to experience issues with register constraints.
+ * - the syscall number is always specified last in order to allow to force
+ * some registers before (gcc refuses a %-register at the last position).
+ *
+ * Also, i386 supports the old_select syscall if newselect is not available
+ */
+#define __ARCH_WANT_SYS_OLD_SELECT
+
+#define my_syscall0(num) \
+({ \
+ long _ret; \
+ register long _num __asm__ ("eax") = (num); \
+ \
+ __asm__ volatile ( \
+ "int $0x80\n" \
+ : "=a" (_ret) \
+ : "0"(_num) \
+ : "memory", "cc" \
+ ); \
+ _ret; \
+})
+
+#define my_syscall1(num, arg1) \
+({ \
+ long _ret; \
+ register long _num __asm__ ("eax") = (num); \
+ register long _arg1 __asm__ ("ebx") = (long)(arg1); \
+ \
+ __asm__ volatile ( \
+ "int $0x80\n" \
+ : "=a" (_ret) \
+ : "r"(_arg1), \
+ "0"(_num) \
+ : "memory", "cc" \
+ ); \
+ _ret; \
+})
+
+#define my_syscall2(num, arg1, arg2) \
+({ \
+ long _ret; \
+ register long _num __asm__ ("eax") = (num); \
+ register long _arg1 __asm__ ("ebx") = (long)(arg1); \
+ register long _arg2 __asm__ ("ecx") = (long)(arg2); \
+ \
+ __asm__ volatile ( \
+ "int $0x80\n" \
+ : "=a" (_ret) \
+ : "r"(_arg1), "r"(_arg2), \
+ "0"(_num) \
+ : "memory", "cc" \
+ ); \
+ _ret; \
+})
+
+#define my_syscall3(num, arg1, arg2, arg3) \
+({ \
+ long _ret; \
+ register long _num __asm__ ("eax") = (num); \
+ register long _arg1 __asm__ ("ebx") = (long)(arg1); \
+ register long _arg2 __asm__ ("ecx") = (long)(arg2); \
+ register long _arg3 __asm__ ("edx") = (long)(arg3); \
+ \
+ __asm__ volatile ( \
+ "int $0x80\n" \
+ : "=a" (_ret) \
+ : "r"(_arg1), "r"(_arg2), "r"(_arg3), \
+ "0"(_num) \
+ : "memory", "cc" \
+ ); \
+ _ret; \
+})
+
+#define my_syscall4(num, arg1, arg2, arg3, arg4) \
+({ \
+ long _ret; \
+ register long _num __asm__ ("eax") = (num); \
+ register long _arg1 __asm__ ("ebx") = (long)(arg1); \
+ register long _arg2 __asm__ ("ecx") = (long)(arg2); \
+ register long _arg3 __asm__ ("edx") = (long)(arg3); \
+ register long _arg4 __asm__ ("esi") = (long)(arg4); \
+ \
+ __asm__ volatile ( \
+ "int $0x80\n" \
+ : "=a" (_ret) \
+ : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), \
+ "0"(_num) \
+ : "memory", "cc" \
+ ); \
+ _ret; \
+})
+
+#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \
+({ \
+ long _ret; \
+ register long _num __asm__ ("eax") = (num); \
+ register long _arg1 __asm__ ("ebx") = (long)(arg1); \
+ register long _arg2 __asm__ ("ecx") = (long)(arg2); \
+ register long _arg3 __asm__ ("edx") = (long)(arg3); \
+ register long _arg4 __asm__ ("esi") = (long)(arg4); \
+ register long _arg5 __asm__ ("edi") = (long)(arg5); \
+ \
+ __asm__ volatile ( \
+ "int $0x80\n" \
+ : "=a" (_ret) \
+ : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
+ "0"(_num) \
+ : "memory", "cc" \
+ ); \
+ _ret; \
+})
+
+#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \
+({ \
+ long _eax = (long)(num); \
+ long _arg6 = (long)(arg6); /* Always in memory */ \
+ __asm__ volatile ( \
+ "pushl %[_arg6]\n\t" \
+ "pushl %%ebp\n\t" \
+ "movl 4(%%esp),%%ebp\n\t" \
+ "int $0x80\n\t" \
+ "popl %%ebp\n\t" \
+ "addl $4,%%esp\n\t" \
+ : "+a"(_eax) /* %eax */ \
+ : "b"(arg1), /* %ebx */ \
+ "c"(arg2), /* %ecx */ \
+ "d"(arg3), /* %edx */ \
+ "S"(arg4), /* %esi */ \
+ "D"(arg5), /* %edi */ \
+ [_arg6]"m"(_arg6) /* memory */ \
+ : "memory", "cc" \
+ ); \
+ _eax; \
+})
+
+/* startup code */
+/*
+ * i386 System V ABI mandates:
+ * 1) last pushed argument must be 16-byte aligned.
+ * 2) The deepest stack frame should be set to zero
+ *
+ */
+void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
+{
+ __asm__ volatile (
+ "xor %ebp, %ebp\n" /* zero the stack frame */
+ "mov %esp, %eax\n" /* save stack pointer to %eax, as arg1 of _start_c */
+ "sub $12, %esp\n" /* sub 12 to keep it aligned after the push %eax */
+ "push %eax\n" /* push arg1 on stack to support plain stack modes too */
+ "call _start_c\n" /* transfer to c runtime */
+ "hlt\n" /* ensure it does not return */
+ );
+ __nolibc_entrypoint_epilogue();
+}
+
+#else /* !defined(__x86_64__) */
+
/* Syscalls for x86_64 :
* - registers are 64-bit
* - syscall number is passed in rax
@@ -214,4 +383,5 @@ __asm__ (
"retq\n"
);
-#endif /* _NOLIBC_ARCH_X86_64_H */
+#endif /* !defined(__x86_64__) */
+#endif /* _NOLIBC_ARCH_X86_H */
diff --git a/tools/include/nolibc/arch.h b/tools/include/nolibc/arch.h
index d20b2304aac21..4ae57aaf97796 100644
--- a/tools/include/nolibc/arch.h
+++ b/tools/include/nolibc/arch.h
@@ -15,10 +15,8 @@
#ifndef _NOLIBC_ARCH_H
#define _NOLIBC_ARCH_H
-#if defined(__x86_64__)
-#include "arch-x86_64.h"
-#elif defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__)
-#include "arch-i386.h"
+#if defined(__x86_64__) || defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__)
+#include "arch-x86.h"
#elif defined(__ARM_EABI__)
#include "arch-arm.h"
#elif defined(__aarch64__)
--
2.17.5