Author: jilles
Date: Thu Sep 6 20:59:49 2012
New Revision: 240178
URL: http://svn.freebsd.org/changeset/base/240178
Log:
libc/amd64: Do not export .cerror.
For some reason, libc exports the symbol .cerror (HIDENAME(cerror)), albeit
in the FBSDprivate_1.0 version. It looks like there is no reason for this
since it is not used from other libraries. Given that it cannot be accessed
from C and its strange calling convention, it is rather unlikely that other
things rely on it. Perhaps it is from a time when symbols could not be
hidden.
Most of the amd64 assembler code jumps to .cerror using the GOT. It can jump
to it directly now, as in non-PIC mode.
There are also some minor size optimizations to instructions but they yield
virtually no benefit in the size of libc.so.7 due to padding.
Reviewed by: kib
Modified:
head/lib/libc/amd64/SYS.h
head/lib/libc/amd64/Symbol.map
head/lib/libc/amd64/gen/rfork_thread.S
head/lib/libc/amd64/sys/brk.S
head/lib/libc/amd64/sys/exect.S
head/lib/libc/amd64/sys/getcontext.S
head/lib/libc/amd64/sys/pipe.S
head/lib/libc/amd64/sys/ptrace.S
head/lib/libc/amd64/sys/reboot.S
head/lib/libc/amd64/sys/sbrk.S
head/lib/libc/amd64/sys/setlogin.S
head/lib/libc/amd64/sys/vfork.S
Modified: head/lib/libc/amd64/SYS.h
==============================================================================
--- head/lib/libc/amd64/SYS.h Thu Sep 6 20:16:59 2012 (r240177)
+++ head/lib/libc/amd64/SYS.h Thu Sep 6 20:59:49 2012 (r240178)
@@ -36,38 +36,20 @@
#include <sys/syscall.h>
#include <machine/asm.h>
-#ifdef PIC
#define RSYSCALL(x) ENTRY(__CONCAT(__sys_,x));
\
.weak CNAME(x); \
.set CNAME(x),CNAME(__CONCAT(__sys_,x)); \
.weak CNAME(__CONCAT(_,x)); \
.set CNAME(__CONCAT(_,x)),CNAME(__CONCAT(__sys_,x)); \
- mov __CONCAT($SYS_,x),%rax; KERNCALL; jb 2f; ret; \
- 2: movq PIC_GOT(HIDENAME(cerror)),%rcx; jmp *%rcx; \
+ mov __CONCAT($SYS_,x),%eax; KERNCALL; \
+ jb HIDENAME(cerror); ret; \
END(__CONCAT(__sys_,x))
#define PSEUDO(x) ENTRY(__CONCAT(__sys_,x));
\
.weak CNAME(__CONCAT(_,x)); \
.set CNAME(__CONCAT(_,x)),CNAME(__CONCAT(__sys_,x)); \
- mov __CONCAT($SYS_,x),%rax; KERNCALL; jb 2f; ret ; \
- 2: movq PIC_GOT(HIDENAME(cerror)),%rcx; jmp *%rcx; \
+ mov __CONCAT($SYS_,x),%eax; KERNCALL; \
+ jb HIDENAME(cerror); ret; \
END(__CONCAT(__sys_,x))
-#else
-#define RSYSCALL(x) ENTRY(__CONCAT(__sys_,x));
\
- .weak CNAME(x); \
- .set CNAME(x),CNAME(__CONCAT(__sys_,x)); \
- .weak CNAME(__CONCAT(_,x)); \
- .set CNAME(__CONCAT(_,x)),CNAME(__CONCAT(__sys_,x)); \
- mov __CONCAT($SYS_,x),%rax; KERNCALL; jb 2f; ret; \
- 2: jmp HIDENAME(cerror); \
- END(__CONCAT(__sys_,x))
-
-#define PSEUDO(x) ENTRY(__CONCAT(__sys_,x));
\
- .weak CNAME(__CONCAT(_,x)); \
- .set CNAME(__CONCAT(_,x)),CNAME(__CONCAT(__sys_,x)); \
- mov __CONCAT($SYS_,x),%rax; KERNCALL; jb 2f; ret; \
- 2: jmp HIDENAME(cerror); \
- END(__CONCAT(__sys_,x))
-#endif
#define KERNCALL movq %rcx, %r10; syscall
Modified: head/lib/libc/amd64/Symbol.map
==============================================================================
--- head/lib/libc/amd64/Symbol.map Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/Symbol.map Thu Sep 6 20:59:49 2012
(r240178)
@@ -66,7 +66,6 @@ FBSDprivate_1.0 {
.curbrk;
.minbrk;
_brk;
- .cerror;
_end;
__sys_vfork;
_vfork;
Modified: head/lib/libc/amd64/gen/rfork_thread.S
==============================================================================
--- head/lib/libc/amd64/gen/rfork_thread.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/gen/rfork_thread.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -93,12 +93,7 @@ ENTRY(rfork_thread)
2:
popq %r12
popq %rbx
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)), %rdx
- jmp *%rdx
-#else
jmp HIDENAME(cerror)
-#endif
END(rfork_thread)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/brk.S
==============================================================================
--- head/lib/libc/amd64/sys/brk.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/brk.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -76,12 +76,7 @@ ok:
ret
err:
addq $8, %rsp
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
jmp HIDENAME(cerror)
-#endif
END(brk)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/exect.S
==============================================================================
--- head/lib/libc/amd64/sys/exect.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/exect.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -47,12 +47,7 @@ ENTRY(exect)
pushq %r8
popfq
KERNCALL
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
jmp HIDENAME(cerror)
-#endif
END(exect)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/getcontext.S
==============================================================================
--- head/lib/libc/amd64/sys/getcontext.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/getcontext.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -42,16 +42,9 @@ ENTRY(__sys_getcontext)
movq (%rsp),%rsi /* save getcontext return address */
mov $SYS_getcontext,%rax
KERNCALL
- jb 1f
+ jb HIDENAME(cerror)
addq $8,%rsp /* remove stale (setcontext) return address */
jmp *%rsi /* restore return address */
-1:
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
- jmp HIDENAME(cerror)
-#endif
END(__sys_getcontext)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/pipe.S
==============================================================================
--- head/lib/libc/amd64/sys/pipe.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/pipe.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -45,18 +45,11 @@ __FBSDID("$FreeBSD$");
ENTRY(__sys_pipe)
mov $SYS_pipe,%rax
KERNCALL
- jb 1f
+ jb HIDENAME(cerror)
movl %eax,(%rdi) /* %rdi is preserved by syscall */
movl %edx,4(%rdi)
movq $0,%rax
ret
-1:
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
- jmp HIDENAME(cerror)
-#endif
END(__sys_pipe)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/ptrace.S
==============================================================================
--- head/lib/libc/amd64/sys/ptrace.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/ptrace.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -48,15 +48,8 @@ ENTRY(ptrace)
#endif
mov $SYS_ptrace,%eax
KERNCALL
- jb err
+ jb HIDENAME(cerror)
ret
-err:
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
- jmp HIDENAME(cerror)
-#endif
END(ptrace)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/reboot.S
==============================================================================
--- head/lib/libc/amd64/sys/reboot.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/reboot.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -45,15 +45,8 @@ __FBSDID("$FreeBSD$");
ENTRY(__sys_reboot)
mov $SYS_reboot,%rax
KERNCALL
- jb 1f
+ jb HIDENAME(cerror)
iretq
-1:
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
- jmp HIDENAME(cerror)
-#endif
END(__sys_reboot)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/sbrk.S
==============================================================================
--- head/lib/libc/amd64/sys/sbrk.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/sbrk.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -79,12 +79,7 @@ back:
ret
err:
addq $8, %rsp
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
jmp HIDENAME(cerror)
-#endif
END(sbrk)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/setlogin.S
==============================================================================
--- head/lib/libc/amd64/sys/setlogin.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/setlogin.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -47,7 +47,7 @@ __FBSDID("$FreeBSD$");
ENTRY(__sys_setlogin)
mov $SYS_setlogin,%rax
KERNCALL
- jb 1f
+ jb HIDENAME(cerror)
#ifdef PIC
movq PIC_GOT(CNAME(_logname_valid)),%rdx
movl $0,(%rdx)
@@ -55,13 +55,6 @@ ENTRY(__sys_setlogin)
movl $0,CNAME(_logname_valid)(%rip)
#endif
ret /* setlogin(name) */
-1:
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
- jmp HIDENAME(cerror)
-#endif
END(__sys_setlogin)
.section .note.GNU-stack,"",%progbits
Modified: head/lib/libc/amd64/sys/vfork.S
==============================================================================
--- head/lib/libc/amd64/sys/vfork.S Thu Sep 6 20:16:59 2012
(r240177)
+++ head/lib/libc/amd64/sys/vfork.S Thu Sep 6 20:59:49 2012
(r240178)
@@ -50,12 +50,7 @@ ENTRY(__sys_vfork)
jmp *%rsi
1:
pushq %rsi
-#ifdef PIC
- movq PIC_GOT(HIDENAME(cerror)),%rdx
- jmp *%rdx
-#else
jmp HIDENAME(cerror)
-#endif
END(__sys_vfork)
.section .note.GNU-stack,"",%progbits
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