mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2025-04-12 16:47:42 +00:00
Code Issues Packages Projects Releases Wiki Activity

tools/nolibc: move entrypoint specifics to compiler.h

Browse Source 
The specific attributes for the _start entrypoint are duplicated for
each architecture.
Deduplicate it into a dedicated #define into compiler.h.

For clang compatibility, the epilogue will also need to be adapted, so
move that one, too.

Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240807-nolibc-llvm-v2-5-c20f2f5fc7c2@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
This commit is contained in:
Thomas Weißschuh 2024-08-07 23:51:41 +02:00
parent 02a62b551c
commit ef32e9b6a3
10 changed files with 21 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
tools/include/nolibc/arch-aarch64.h
View File

@ -142,13 +142,13 @@
}) })
/* startup code */ /* startup code */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{ {
__asm__ volatile ( __asm__ volatile (
"mov x0, sp\n" /* save stack pointer to x0, as arg1 of _start_c */ "mov x0, sp\n" /* save stack pointer to x0, as arg1 of _start_c */
"and sp, x0, -16\n" /* sp must be 16-byte aligned in the callee */ "and sp, x0, -16\n" /* sp must be 16-byte aligned in the callee */
"bl _start_c\n" /* transfer to c runtime */ "bl _start_c\n" /* transfer to c runtime */
); );
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
#endif /* _NOLIBC_ARCH_AARCH64_H */ #endif /* _NOLIBC_ARCH_AARCH64_H */

4
tools/include/nolibc/arch-arm.h
View File

@ -185,7 +185,7 @@
}) })
/* startup code */ /* startup code */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{ {
__asm__ volatile ( __asm__ volatile (
"mov r0, sp\n" /* save stack pointer to %r0, as arg1 of _start_c */ "mov r0, sp\n" /* save stack pointer to %r0, as arg1 of _start_c */
@ -193,7 +193,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
"mov sp, ip\n" "mov sp, ip\n"
"bl _start_c\n" /* transfer to c runtime */ "bl _start_c\n" /* transfer to c runtime */
); );
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
#endif /* _NOLIBC_ARCH_ARM_H */ #endif /* _NOLIBC_ARCH_ARM_H */

4
tools/include/nolibc/arch-i386.h
View File

@ -162,7 +162,7 @@
* 2) The deepest stack frame should be set to zero * 2) The deepest stack frame should be set to zero
* *
*/ */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{ {
__asm__ volatile ( __asm__ volatile (
"xor %ebp, %ebp\n" /* zero the stack frame */ "xor %ebp, %ebp\n" /* zero the stack frame */
@ -174,7 +174,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
"call _start_c\n" /* transfer to c runtime */ "call _start_c\n" /* transfer to c runtime */
"hlt\n" /* ensure it does not return */ "hlt\n" /* ensure it does not return */
); );
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
#endif /* _NOLIBC_ARCH_I386_H */ #endif /* _NOLIBC_ARCH_I386_H */

4
tools/include/nolibc/arch-loongarch.h
View File

@ -149,14 +149,14 @@
#endif #endif
/* startup code */ /* startup code */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{ {
__asm__ volatile ( __asm__ volatile (
"move $a0, $sp\n" /* save stack pointer to $a0, as arg1 of _start_c */ "move $a0, $sp\n" /* save stack pointer to $a0, as arg1 of _start_c */
LONG_BSTRINS " $sp, $zero, 3, 0\n" /* $sp must be 16-byte aligned */ LONG_BSTRINS " $sp, $zero, 3, 0\n" /* $sp must be 16-byte aligned */
"bl _start_c\n" /* transfer to c runtime */ "bl _start_c\n" /* transfer to c runtime */
); );
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
#endif /* _NOLIBC_ARCH_LOONGARCH_H */ #endif /* _NOLIBC_ARCH_LOONGARCH_H */

4
tools/include/nolibc/arch-mips.h
View File

@ -179,7 +179,7 @@
}) })
/* startup code, note that it's called __start on MIPS */ /* startup code, note that it's called __start on MIPS */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector __start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector __start(void)
{ {
__asm__ volatile ( __asm__ volatile (
".set push\n" ".set push\n"
@ -200,7 +200,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
" nop\n" /* delayed slot */ " nop\n" /* delayed slot */
".set pop\n" ".set pop\n"
); );
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
#endif /* _NOLIBC_ARCH_MIPS_H */ #endif /* _NOLIBC_ARCH_MIPS_H */

4
tools/include/nolibc/arch-powerpc.h
View File

@ -184,7 +184,7 @@
#endif /* !__powerpc64__ */ #endif /* !__powerpc64__ */
/* startup code */ /* startup code */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{ {
#ifdef __powerpc64__ #ifdef __powerpc64__
#if _CALL_ELF == 2 #if _CALL_ELF == 2
@ -215,7 +215,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
"bl _start_c\n" /* transfer to c runtime */ "bl _start_c\n" /* transfer to c runtime */
); );
#endif #endif
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
#endif /* _NOLIBC_ARCH_POWERPC_H */ #endif /* _NOLIBC_ARCH_POWERPC_H */

4
tools/include/nolibc/arch-riscv.h
View File

@ -140,7 +140,7 @@
}) })
/* startup code */ /* startup code */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{ {
__asm__ volatile ( __asm__ volatile (
".option push\n" ".option push\n"
@ -151,7 +151,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
"andi sp, a0, -16\n" /* sp must be 16-byte aligned */ "andi sp, a0, -16\n" /* sp must be 16-byte aligned */
"call _start_c\n" /* transfer to c runtime */ "call _start_c\n" /* transfer to c runtime */
); );
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
#endif /* _NOLIBC_ARCH_RISCV_H */ #endif /* _NOLIBC_ARCH_RISCV_H */

4
tools/include/nolibc/arch-s390.h
View File

@ -139,7 +139,7 @@
}) })
/* startup code */ /* startup code */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{ {
__asm__ volatile ( __asm__ volatile (
"lgr %r2, %r15\n" /* save stack pointer to %r2, as arg1 of _start_c */ "lgr %r2, %r15\n" /* save stack pointer to %r2, as arg1 of _start_c */
@ -147,7 +147,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
"xc 0(8,%r15), 0(%r15)\n" /* clear backchain */ "xc 0(8,%r15), 0(%r15)\n" /* clear backchain */
"brasl %r14, _start_c\n" /* transfer to c runtime */ "brasl %r14, _start_c\n" /* transfer to c runtime */
); );
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
struct s390_mmap_arg_struct { struct s390_mmap_arg_struct {

4
tools/include/nolibc/arch-x86_64.h
View File

@ -161,7 +161,7 @@
* 2) The deepest stack frame should be zero (the %rbp). * 2) The deepest stack frame should be zero (the %rbp).
* *
*/ */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void) void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector _start(void)
{ {
__asm__ volatile ( __asm__ volatile (
"xor %ebp, %ebp\n" /* zero the stack frame */ "xor %ebp, %ebp\n" /* zero the stack frame */
@ -170,7 +170,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
"call _start_c\n" /* transfer to c runtime */ "call _start_c\n" /* transfer to c runtime */
"hlt\n" /* ensure it does not return */ "hlt\n" /* ensure it does not return */
); );
__builtin_unreachable(); __nolibc_entrypoint_epilogue();
} }
#define NOLIBC_ARCH_HAS_MEMMOVE #define NOLIBC_ARCH_HAS_MEMMOVE

3
tools/include/nolibc/compiler.h
View File

@ -12,6 +12,9 @@
# define __nolibc_has_attribute(attr) 0 # define __nolibc_has_attribute(attr) 0
#endif #endif
#define __nolibc_entrypoint __attribute__((optimize("Os", "omit-frame-pointer")))
#define __nolibc_entrypoint_epilogue() __builtin_unreachable()
#if defined(__SSP__) || defined(__SSP_STRONG__) || defined(__SSP_ALL__) || defined(__SSP_EXPLICIT__) #if defined(__SSP__) || defined(__SSP_STRONG__) || defined(__SSP_ALL__) || defined(__SSP_EXPLICIT__)
#define _NOLIBC_STACKPROTECTOR #define _NOLIBC_STACKPROTECTOR