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[PATCH] i386: Remove support for GCC versions before 5 from <sysdep.h>
- From: Florian Weimer <fweimer at redhat dot com>
- To: libc-alpha at sourceware dot org
- Date: Thu, 31 Jan 2019 23:27:14 +0100
- Subject: [PATCH] i386: Remove support for GCC versions before 5 from <sysdep.h>
Tested on i386.
2019-01-31 Florian Weimer <fweimer@redhat.com>
i386: Remove support for GCC versions before 5 from <sysdep.h>.
* sysdeps/unix/sysv/linux/i386/sysdep.h [!OPTIMIZE_FOR_GCC_5]
(bpushl, bpopl, struct libc_do_syscall_args, INTERNAL_SYSCALL_MAIN_6)
(INTERNAL_SYSCALL_MAIN_INLINE, INTERNAL_SYSCALL_NCS)
(check_consistency): Remove.
* elf/dl-load.c (_dl_map_object_from_fd): Remove call to
check_consistency.
* sysdeps/unix/sysv/linux/dl-execstack.c
(_dl_make_stack_executable): Likewise.
diff --git a/elf/dl-load.c b/elf/dl-load.c
index f972524421..80c23446ba 100644
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -1281,10 +1281,6 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
#endif
__stack_prot |= PROT_READ|PROT_WRITE|PROT_EXEC;
-#ifdef check_consistency
- check_consistency ();
-#endif
-
errval = (*GL(dl_make_stack_executable_hook)) (stack_endp);
if (errval)
{
diff --git a/sysdeps/unix/sysv/linux/dl-execstack.c b/sysdeps/unix/sysv/linux/dl-execstack.c
index ac1aa72f3b..28f3bd90e0 100644
--- a/sysdeps/unix/sysv/linux/dl-execstack.c
+++ b/sysdeps/unix/sysv/linux/dl-execstack.c
@@ -50,10 +50,6 @@ _dl_make_stack_executable (void **stack_endp)
GL(dl_stack_flags) |= PF_X;
out:
-#ifdef check_consistency
- check_consistency ();
-#endif
-
return result;
}
rtld_hidden_def (_dl_make_stack_executable)
diff --git a/sysdeps/unix/sysv/linux/i386/sysdep.h b/sysdeps/unix/sysv/linux/i386/sysdep.h
index 0be10744ff..7bfb42dbbb 100644
--- a/sysdeps/unix/sysv/linux/i386/sysdep.h
+++ b/sysdeps/unix/sysv/linux/i386/sysdep.h
@@ -241,48 +241,6 @@
extern int __syscall_error (int)
attribute_hidden __attribute__ ((__regparm__ (1)));
-#ifndef OPTIMIZE_FOR_GCC_5
-/* We need some help from the assembler to generate optimal code. We
- define some macros here which later will be used. */
-asm (".L__X'%ebx = 1\n\t"
- ".L__X'%ecx = 2\n\t"
- ".L__X'%edx = 2\n\t"
- ".L__X'%eax = 3\n\t"
- ".L__X'%esi = 3\n\t"
- ".L__X'%edi = 3\n\t"
- ".L__X'%ebp = 3\n\t"
- ".L__X'%esp = 3\n\t"
- ".macro bpushl name reg\n\t"
- ".if 1 - \\name\n\t"
- ".if 2 - \\name\n\t"
- "error\n\t"
- ".else\n\t"
- "xchgl \\reg, %ebx\n\t"
- ".endif\n\t"
- ".endif\n\t"
- ".endm\n\t"
- ".macro bpopl name reg\n\t"
- ".if 1 - \\name\n\t"
- ".if 2 - \\name\n\t"
- "error\n\t"
- ".else\n\t"
- "xchgl \\reg, %ebx\n\t"
- ".endif\n\t"
- ".endif\n\t"
- ".endm\n\t");
-
-/* Six-argument syscalls use an out-of-line helper, because an inline
- asm using all registers apart from %esp cannot work reliably and
- the assembler does not support describing an asm that saves and
- restores %ebp itself as a separate stack frame. This structure
- stores the arguments not passed in registers; %edi is passed with a
- pointer to this structure. */
-struct libc_do_syscall_args
-{
- int ebx, edi, ebp;
-};
-#endif
-
/* Define a macro which expands inline into the wrapper code for a system
call. */
#undef INLINE_SYSCALL
@@ -336,43 +294,23 @@ struct libc_do_syscall_args
INTERNAL_SYSCALL_MAIN_INLINE(name, err, 4, args)
#define INTERNAL_SYSCALL_MAIN_5(name, err, args...) \
INTERNAL_SYSCALL_MAIN_INLINE(name, err, 5, args)
-/* Each object using 6-argument inline syscalls must include a
- definition of __libc_do_syscall. */
-#ifdef OPTIMIZE_FOR_GCC_5
-# define INTERNAL_SYSCALL_MAIN_6(name, err, args...) \
+#define INTERNAL_SYSCALL_MAIN_6(name, err, args...) \
INTERNAL_SYSCALL_MAIN_INLINE(name, err, 6, args)
-#else /* GCC 5 */
-# define INTERNAL_SYSCALL_MAIN_6(name, err, arg1, arg2, arg3, \
- arg4, arg5, arg6) \
- struct libc_do_syscall_args _xv = \
- { \
- (int) (arg1), \
- (int) (arg5), \
- (int) (arg6) \
- }; \
- asm volatile ( \
- "movl %1, %%eax\n\t" \
- "call __libc_do_syscall" \
- : "=a" (resultvar) \
- : "i" (__NR_##name), "c" (arg2), "d" (arg3), "S" (arg4), "D" (&_xv) \
- : "memory", "cc")
-#endif /* GCC 5 */
#define INTERNAL_SYSCALL(name, err, nr, args...) \
({ \
register unsigned int resultvar; \
INTERNAL_SYSCALL_MAIN_##nr (name, err, args); \
(int) resultvar; })
#if I386_USE_SYSENTER
-# ifdef OPTIMIZE_FOR_GCC_5
-# ifdef PIC
-# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
+# ifdef PIC
+# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
LOADREGS_##nr(args) \
asm volatile ( \
"call *%%gs:%P2" \
: "=a" (resultvar) \
: "a" (__NR_##name), "i" (offsetof (tcbhead_t, sysinfo)) \
ASMARGS_##nr(args) : "memory", "cc")
-# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
+# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
({ \
register unsigned int resultvar; \
LOADREGS_##nr(args) \
@@ -382,14 +320,14 @@ struct libc_do_syscall_args
: "a" (name), "i" (offsetof (tcbhead_t, sysinfo)) \
ASMARGS_##nr(args) : "memory", "cc"); \
(int) resultvar; })
-# else
-# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
+# else
+# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
LOADREGS_##nr(args) \
asm volatile ( \
"call *_dl_sysinfo" \
: "=a" (resultvar) \
: "a" (__NR_##name) ASMARGS_##nr(args) : "memory", "cc")
-# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
+# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
({ \
register unsigned int resultvar; \
LOADREGS_##nr(args) \
@@ -398,63 +336,15 @@ struct libc_do_syscall_args
: "=a" (resultvar) \
: "a" (name) ASMARGS_##nr(args) : "memory", "cc"); \
(int) resultvar; })
-# endif
-# else /* GCC 5 */
-# ifdef PIC
-# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
- EXTRAVAR_##nr \
- asm volatile ( \
- LOADARGS_##nr \
- "movl %1, %%eax\n\t" \
- "call *%%gs:%P2\n\t" \
- RESTOREARGS_##nr \
- : "=a" (resultvar) \
- : "i" (__NR_##name), "i" (offsetof (tcbhead_t, sysinfo)) \
- ASMFMT_##nr(args) : "memory", "cc")
-# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
- ({ \
- register unsigned int resultvar; \
- EXTRAVAR_##nr \
- asm volatile ( \
- LOADARGS_##nr \
- "call *%%gs:%P2\n\t" \
- RESTOREARGS_##nr \
- : "=a" (resultvar) \
- : "0" (name), "i" (offsetof (tcbhead_t, sysinfo)) \
- ASMFMT_##nr(args) : "memory", "cc"); \
- (int) resultvar; })
-# else
-# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
- EXTRAVAR_##nr \
- asm volatile ( \
- LOADARGS_##nr \
- "movl %1, %%eax\n\t" \
- "call *_dl_sysinfo\n\t" \
- RESTOREARGS_##nr \
- : "=a" (resultvar) \
- : "i" (__NR_##name) ASMFMT_##nr(args) : "memory", "cc")
-# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
- ({ \
- register unsigned int resultvar; \
- EXTRAVAR_##nr \
- asm volatile ( \
- LOADARGS_##nr \
- "call *_dl_sysinfo\n\t" \
- RESTOREARGS_##nr \
- : "=a" (resultvar) \
- : "0" (name) ASMFMT_##nr(args) : "memory", "cc"); \
- (int) resultvar; })
-# endif
-# endif /* GCC 5 */
+# endif
#else
-# ifdef OPTIMIZE_FOR_GCC_5
-# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
+# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
LOADREGS_##nr(args) \
asm volatile ( \
"int $0x80" \
: "=a" (resultvar) \
: "a" (__NR_##name) ASMARGS_##nr(args) : "memory", "cc")
-# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
+# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
({ \
register unsigned int resultvar; \
LOADREGS_##nr(args) \
@@ -463,28 +353,6 @@ struct libc_do_syscall_args
: "=a" (resultvar) \
: "a" (name) ASMARGS_##nr(args) : "memory", "cc"); \
(int) resultvar; })
-# else /* GCC 5 */
-# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
- EXTRAVAR_##nr \
- asm volatile ( \
- LOADARGS_##nr \
- "movl %1, %%eax\n\t" \
- "int $0x80\n\t" \
- RESTOREARGS_##nr \
- : "=a" (resultvar) \
- : "i" (__NR_##name) ASMFMT_##nr(args) : "memory", "cc")
-# define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
- ({ \
- register unsigned int resultvar; \
- EXTRAVAR_##nr \
- asm volatile ( \
- LOADARGS_##nr \
- "int $0x80\n\t" \
- RESTOREARGS_##nr \
- : "=a" (resultvar) \
- : "0" (name) ASMFMT_##nr(args) : "memory", "cc"); \
- (int) resultvar; })
-# endif /* GCC 5 */
#endif
#undef INTERNAL_SYSCALL_DECL
@@ -549,35 +417,33 @@ struct libc_do_syscall_args
# define RESTOREARGS_5
#endif
-#ifdef OPTIMIZE_FOR_GCC_5
-# define LOADREGS_0()
-# define ASMARGS_0()
-# define LOADREGS_1(arg1) \
+#define LOADREGS_0()
+#define ASMARGS_0()
+#define LOADREGS_1(arg1) \
LOADREGS_0 ()
-# define ASMARGS_1(arg1) \
+#define ASMARGS_1(arg1) \
ASMARGS_0 (), "b" ((unsigned int) (arg1))
-# define LOADREGS_2(arg1, arg2) \
+#define LOADREGS_2(arg1, arg2) \
LOADREGS_1 (arg1)
-# define ASMARGS_2(arg1, arg2) \
+#define ASMARGS_2(arg1, arg2) \
ASMARGS_1 (arg1), "c" ((unsigned int) (arg2))
-# define LOADREGS_3(arg1, arg2, arg3) \
+#define LOADREGS_3(arg1, arg2, arg3) \
LOADREGS_2 (arg1, arg2)
-# define ASMARGS_3(arg1, arg2, arg3) \
+#define ASMARGS_3(arg1, arg2, arg3) \
ASMARGS_2 (arg1, arg2), "d" ((unsigned int) (arg3))
-# define LOADREGS_4(arg1, arg2, arg3, arg4) \
+#define LOADREGS_4(arg1, arg2, arg3, arg4) \
LOADREGS_3 (arg1, arg2, arg3)
-# define ASMARGS_4(arg1, arg2, arg3, arg4) \
+#define ASMARGS_4(arg1, arg2, arg3, arg4) \
ASMARGS_3 (arg1, arg2, arg3), "S" ((unsigned int) (arg4))
-# define LOADREGS_5(arg1, arg2, arg3, arg4, arg5) \
+#define LOADREGS_5(arg1, arg2, arg3, arg4, arg5) \
LOADREGS_4 (arg1, arg2, arg3, arg4)
-# define ASMARGS_5(arg1, arg2, arg3, arg4, arg5) \
+#define ASMARGS_5(arg1, arg2, arg3, arg4, arg5) \
ASMARGS_4 (arg1, arg2, arg3, arg4), "D" ((unsigned int) (arg5))
-# define LOADREGS_6(arg1, arg2, arg3, arg4, arg5, arg6) \
+#define LOADREGS_6(arg1, arg2, arg3, arg4, arg5, arg6) \
register unsigned int _a6 asm ("ebp") = (unsigned int) (arg6); \
LOADREGS_5 (arg1, arg2, arg3, arg4, arg5)
-# define ASMARGS_6(arg1, arg2, arg3, arg4, arg5, arg6) \
+#define ASMARGS_6(arg1, arg2, arg3, arg4, arg5, arg6) \
ASMARGS_5 (arg1, arg2, arg3, arg4, arg5), "r" (_a6)
-#endif /* GCC 5 */
#define ASMFMT_0()
#ifdef __PIC__
@@ -615,20 +481,6 @@ struct libc_do_syscall_args
# define EXTRAVAR_5
#endif
-/* Consistency check for position-independent code. */
-#if defined __PIC__ && !defined OPTIMIZE_FOR_GCC_5
-# define check_consistency() \
- ({ int __res; \
- __asm__ __volatile__ \
- (LOAD_PIC_REG_STR (cx) ";" \
- "subl %%ebx, %%ecx;" \
- "je 1f;" \
- "ud2;" \
- "1:\n" \
- : "=c" (__res)); \
- __res; })
-#endif
-
#endif /* __ASSEMBLER__ */