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-rw-r--r--libc/sysdeps/linux/i386/bits/syscalls.h82
-rw-r--r--libc/sysdeps/linux/i386/clone.S17
-rw-r--r--libc/sysdeps/linux/i386/sigaction.c4
3 files changed, 28 insertions, 75 deletions
diff --git a/libc/sysdeps/linux/i386/bits/syscalls.h b/libc/sysdeps/linux/i386/bits/syscalls.h
index eeafb3a48..1f60a4493 100644
--- a/libc/sysdeps/linux/i386/bits/syscalls.h
+++ b/libc/sysdeps/linux/i386/bits/syscalls.h
@@ -13,6 +13,7 @@
#ifndef __ASSEMBLER__
#include <errno.h>
+#include <common/sysdep.h>
#define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
({ \
@@ -31,90 +32,21 @@
#if 1 /* defined __PIC__ || defined __pic__ */
-/* This code avoids pushing/popping ebx as much as possible.
- * I think the main reason was that older GCCs had problems
- * with proper saving/restoring of ebx if "b" constraint was used,
- * which was breaking -fPIC code really badly.
- * At least gcc 4.2.x seems to not need these tricks anymore,
- * but this code is still useful because it often avoids
- * using stack for saving ebx.
- * Keeping it unconditionally enabled for now.
- */
-
-/* We need some help from the assembler to generate optimal code.
- * We define some macros here which later will be used. */
-/* gcc>=4.6 with LTO need the same guards as IMA (a.k.a --combine) did.
- * See gcc.gnu.org/PR47577 */
-/* FIXME: drop these b* macros! */
-
-__asm__ (
-#if defined __DOMULTI__ || __GNUC_PREREQ (4, 6)
- /* Protect against asm macro redefinition (happens in __DOMULTI__ mode).
- * Unfortunately, it ends up visible in .o files. */
- ".ifndef _BITS_SYSCALLS_ASM\n\t"
- ".set _BITS_SYSCALLS_ASM,1\n\t"
-#endif
- ".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"
-
- /* Loading param #1 (ebx) is done by loading it into
- * another register, and then performing bpushl+bmovl,
- * since we must preserve ebx */
-
- ".macro bpushl name reg\n\t"
- ".if 1 - \\name\n\t" /* if reg!=ebx... */
- ".if 2 - \\name\n\t" /* if reg can't be clobbered... */
- "pushl %ebx\n\t" /* save ebx on stack */
- ".else\n\t"
- "xchgl \\reg, %ebx\n\t" /* else save ebx in reg, and load reg to ebx */
- ".endif\n\t"
- ".endif\n\t"
- ".endm\n\t"
-
- ".macro bmovl name reg\n\t"
- ".if 1 - \\name\n\t"
- ".if 2 - \\name\n\t" /* if reg can't be clobbered... */
- "movl \\reg, %ebx\n\t" /* load reg to ebx */
- ".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" /* if reg can't be clobbered... */
- "popl %ebx\n\t" /* restore ebx from stack */
- ".else\n\t"
- "xchgl \\reg, %ebx\n\t" /* else restore ebx from reg */
- ".endif\n\t"
- ".endif\n\t"
- ".endm\n\t"
-
-#if defined __DOMULTI__ || __GNUC_PREREQ (4, 6)
- ".endif\n\t" /* _BITS_SYSCALLS_ASM */
-#endif
-);
-
#define LOADARGS_0
-#define LOADARGS_1 "bpushl .L__X'%k2, %k2\n\t" "bmovl .L__X'%k2, %k2\n\t"
+#define LOADARGS_1 "push %%ebx\n\t" CFI_ADJUST_CFA_OFFSET(4) "\n\t" CFI_REL_OFFSET(ebx, 0) "\n\t" "movl %k2, %%ebx\n\t"
#define LOADARGS_2 LOADARGS_1
#define LOADARGS_3 LOADARGS_1
#define LOADARGS_4 LOADARGS_1
#define LOADARGS_5 LOADARGS_1
-#define LOADARGS_6 LOADARGS_1 "push %%ebp\n\t" "movl %7, %%ebp\n\t"
+#define LOADARGS_6 LOADARGS_1 "push %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(4) "\n\t" CFI_REL_OFFSET(ebp, 0) "\n\t" "movl %7, %%ebp\n\t"
#define RESTOREARGS_0
-#define RESTOREARGS_1 "bpopl .L__X'%k2, %k2\n\t"
+#define RESTOREARGS_1 "pop %%ebx\n\t" CFI_ADJUST_CFA_OFFSET(-4) "\n\t" CFI_RESTORE(ebx) "\n\t" RESTOREARGS_0
#define RESTOREARGS_2 RESTOREARGS_1
#define RESTOREARGS_3 RESTOREARGS_1
#define RESTOREARGS_4 RESTOREARGS_1
#define RESTOREARGS_5 RESTOREARGS_1
-#define RESTOREARGS_6 "pop %%ebp\n\t" RESTOREARGS_1
+#define RESTOREARGS_6 "pop %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(-4) "\n\t" CFI_RESTORE(ebp) "\n\t" RESTOREARGS_1
#define ASMFMT_0()
/* "acdSD" constraint would work too, but "SD" would use esi/edi and cause
@@ -162,7 +94,7 @@ __asm__ (
#define LOADARGS_3
#define LOADARGS_4
#define LOADARGS_5
-#define LOADARGS_6 "push %%ebp\n\t" "movl %7, %%ebp\n\t"
+#define LOADARGS_6 "push %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(4) "\n\t" CFI_REL_OFFSET(ebp, 0) "\n\t" "movl %7, %%ebp\n\t"
#define RESTOREARGS_0
#define RESTOREARGS_1
@@ -170,7 +102,7 @@ __asm__ (
#define RESTOREARGS_3
#define RESTOREARGS_4
#define RESTOREARGS_5
-#define RESTOREARGS_6 "pop %%ebp\n\t"
+#define RESTOREARGS_6 "pop %%ebp\n\t" CFI_ADJUST_CFA_OFFSET(-4) "\n\t" CFI_RESTORE(ebp) "\n\t"
#define ASMFMT_0()
#define ASMFMT_1(arg1) \
diff --git a/libc/sysdeps/linux/i386/clone.S b/libc/sysdeps/linux/i386/clone.S
index a7de3fe27..cf6cd35ec 100644
--- a/libc/sysdeps/linux/i386/clone.S
+++ b/libc/sysdeps/linux/i386/clone.S
@@ -25,6 +25,7 @@
#define _ERRNO_H 1
#include <bits/errno.h>
+#include <sysdep.h>
#include <sys/syscall.h>
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
@@ -45,6 +46,7 @@
.global clone
.type clone,%function
clone:
+ cfi_startproc;
/* Sanity check arguments. */
movl $-EINVAL,%eax
@@ -86,17 +88,28 @@ clone:
/* Do the system call */
pushl %ebx
+ cfi_adjust_cfa_offset (4)
pushl %esi
+ cfi_adjust_cfa_offset (4)
pushl %edi
+ cfi_adjust_cfa_offset (4)
+
movl TLS+12(%esp),%esi
+ cfi_rel_offset (esi, 4)
movl PTID+12(%esp),%edx
movl FLAGS+12(%esp),%ebx
+ cfi_rel_offset (ebx, 8)
movl CTID+12(%esp),%edi
+ cfi_rel_offset (edi, 0)
movl $__NR_clone,%eax
#ifdef RESET_PID
/* Remember the flag value. */
movl %ebx, (%ecx)
#endif
+ /* End FDE now, because in the child the unwind info will be
+ wrong. */
+ cfi_endproc
+
int $0x80
popl %edi
popl %esi
@@ -108,6 +121,9 @@ clone:
ret
.Lthread_start:
+ cfi_startproc;
+ /* Clearing frame pointer is insufficient, use CFI. */
+ cfi_undefined (eip);
/* Note: %esi is zero. */
movl %esi,%ebp /* terminate the stack frame */
call *%ebx
@@ -120,6 +136,7 @@ clone:
movl %eax, %ebx
movl $__NR_exit, %eax
int $0x80
+ cfi_endproc;
/* Need to indirect jump to syscall error
* or we end up with TEXTREL's
diff --git a/libc/sysdeps/linux/i386/sigaction.c b/libc/sysdeps/linux/i386/sigaction.c
index de0c75ded..f9af3f748 100644
--- a/libc/sysdeps/linux/i386/sigaction.c
+++ b/libc/sysdeps/linux/i386/sigaction.c
@@ -112,6 +112,9 @@ libc_hidden_weak(sigaction)
#define RESTORE2(name, syscall) \
__asm__ ( \
".text\n" \
+ ".align 8\n" \
+ " nop\n" \
+ ".align 16\n" \
"__" #name ":\n" \
" movl $" #syscall ", %eax\n" \
" int $0x80\n" \
@@ -128,6 +131,7 @@ RESTORE(restore_rt, __NR_rt_sigreturn)
# define RESTORE2(name, syscall) \
__asm__ ( \
".text\n" \
+ ".align 8\n" \
"__" #name ":\n" \
" popl %eax\n" \
" movl $" #syscall ", %eax\n" \
generated by cgit v1.2.3 (git 2.25.1) at 2025-09-13 02:23:14 +0000