Date: Thu, 6 Sep 2012 20:59:49 +0000 (UTC) From: Jilles Tjoelker <jilles@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r240178 - in head/lib/libc/amd64: . gen sys Message-ID: <201209062059.q86KxnNd083737@svn.freebsd.org>
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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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