xnu-1699.32.7.tar.gz

[apple/xnu.git] / libsyscall / custom / __vfork.s

diff --git a/libsyscall/custom/__vfork.s b/libsyscall/custom/__vfork.s
index c6e559ccde4387cd8f467032ea7f18f27153c632..91408f9c3a0280da710d1959e1333560f4409a01 100644 (file)
--- a/libsyscall/custom/__vfork.s
+++ b/libsyscall/custom/__vfork.s
@@ -37,56 +37,7 @@
 
 #include "SYS.h"
 
-#if defined(__ppc__) || defined(__ppc64__)
-
-/* We use mode-independent "g" opcodes such as "srgi", and/or
- * mode-independent macros such as MI_GET_ADDRESS.  These expand
- * into word operations when targeting __ppc__, and into doubleword
- * operations when targeting __ppc64__.
- */
-#include <architecture/ppc/mode_independent_asm.h>
-
-/* In vfork(), the child runs in parent's address space.  */
-
-
-MI_ENTRY_POINT(___vfork)
-    MI_GET_ADDRESS(r5,__current_pid)  // get address of __current_pid in r5
-2:
-       lwarx   r6,0,r5                 // don't cache pid across vfork
-       cmpwi   r6,0
-       ble--   3f              // is another vfork in progress
-       li      r6,0                    // if not, erase the stored pid
-3:     
-       addi    r6,r6,-1                // count the parallel vforks in
-       stwcx.  r6,0,r5                 // negative cached pid values
-       bne--   2b
-       
-       li      r0,SYS_vfork
-       sc
-       b       Lbotch                  // error return
-
-       cmpwi   r4,0
-       beq     Lparent                 // parent, since a1 == 0 in parent,
-
-       li      r3,0                    // child
-       blr
-
-Lparent:                    // r3 == child's pid
-       lwarx   r6,0,r5                 // we're back, decrement vfork count
-       addi    r6,r6,1
-       stwcx.  r6,0,r5
-       bne--   Lparent
-       blr                     // return pid
-
-Lbotch:
-       lwarx   r6,0,r5                 // never went, decrement vfork count
-       addi    r6,r6,1
-       stwcx.  r6,0,r5
-       bne--   Lbotch
-
-       MI_BRANCH_EXTERNAL(cerror)
-
-#elif defined(__i386__)
+#if defined(__i386__)
 
 #if defined(__DYNAMIC__)
 #define GET_CURRENT_PID        PICIFY(__current_pid)
@@ -158,6 +109,7 @@ LEAF(___vfork, 0)
        movq            $ SYSCALL_CONSTRUCT_UNIX(SYS_vfork), %rax       // code for vfork -> rax
        UNIX_SYSCALL_TRAP                       // do the system call
        jnb             L1                                      // jump if CF==0
+       pushq           %rdi                    // put return address back on stack for cerror
        movq            __current_pid@GOTPCREL(%rip), %rcx
        lock
        addq            $1, (%rcx)
@@ -176,71 +128,6 @@ L2:
        addq            $1, (%rdx)
        jmp             *%rdi
 
-#elif defined(__arm__)
-
-#include <arm/arch.h>
-               
-       .globl  cerror
-       MI_ENTRY_POINT(_vfork)
-
-       MI_GET_ADDRESS(r3, __current_pid)       // get address of __current_pid
-#ifdef _ARM_ARCH_6
-L0:    
-       ldrex   r1, [r3]
-       subs    r1, r1, #1                      // if __current_pid <= 0, decrement it
-       movpl   r1, #-1                         // otherwise put -1 in there
-       strex   r2, r1, [r3]
-       cmp     r2, #0
-       bne     L0
-#else
-       mov     r2, #0x80000000                 // load "looking" value
-L0:    
-       swp     r1, r2, [r3]                    // look at the value, lock others out
-       cmp     r1, r2                          // anyone else trying to look?
-       beq     L0                              // yes, so wait our turn
-        subs    r1, r1, #1                      // if __current_pid <= 0, decrement it
-       movpl   r1, #-1                         // otherwise put -1 in there
-       str     r1, [r3]
-#endif
-               
-       mov     r1, #1                                  // prime results
-       mov     r12, #SYS_vfork
-       swi     #SWI_SYSCALL                            // make the syscall
-       bcs     Lbotch                                  // error?
-       cmp     r1, #0                                  // parent (r1=0) or child(r1=1)
-       beq     Lparent
-
-       //child here...
-       mov     r0, #0
-       bx      lr                                      // return
-
-Lbotch:
-       MI_CALL_EXTERNAL(cerror)                        // jump here on error
-       mov     r0,#-1                                  // set the error
-       // reload values clobbered by cerror (so we can treat them as live in Lparent)
-       MI_GET_ADDRESS(r3, __current_pid)               // get address of __current_pid
-#ifndef _ARM_ARCH_6
-       mov     r2, #0x80000000                 // load "looking" value
-#endif
-       // fall thru
-       
-Lparent:       
-#ifdef _ARM_ARCH_6
-       ldrex   r1, [r3]
-       add     r1, r1, #1                      // we're back, decrement vfork count
-       strex   r2, r1, [r3]
-       cmp     r2, #0
-       bne     Lparent
-#else
-       swp     r1, r2, [r3]                    // look at the value, lock others out
-       cmp     r1, r2                          // anyone else trying to look?
-       beq     Lparent                         // yes, so wait our turn
-       add     r1, r1, #1                      // we're back, decrement vfork count
-       str     r1, [r3]
-#endif
-
-       bx      lr                                      // return
-
 #else
 #error Unsupported architecture
 #endif