xtensa: add support for NPTL

Changes from:
https://github.com/foss-xtensa/uClibc/commits/xtensa_nptl

Author: Chris Zankel <chris@zankel.net>
Author: Baruch Siach <baruch@tkos.co.il>

7 files changed, 310 insertions, 140 deletions

diff --git a/libc/sysdeps/linux/xtensa/Makefile.arch b/libc/sysdeps/linux/xtensa/Makefile.arch
index 277a1e325..b9b6b87d5 100644
--- a/libc/sysdeps/linux/xtensa/Makefile.arch
+++ b/libc/sysdeps/linux/xtensa/Makefile.arch
@@ -5,7 +5,10 @@
 # Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
 #
 
-CSRC-y := brk.c fork.c sigaction.c __syscall_error.c
+CSRC-y := brk.c sigaction.c __syscall_error.c
 
 SSRC-y := bsd-_setjmp.S bsd-setjmp.S setjmp.S clone.S \
 	sigrestorer.S syscall.S mmap.S windowspill.S __longjmp.S vfork.S
+
+CSRC-$(if $(UCLIBC_HAS_THREADS_NATIVE),,y) += fork.c
+SSRC-$(if $(UCLIBC_HAS_THREADS_NATIVE),,y) += clone.S
diff --git a/libc/sysdeps/linux/xtensa/clone.S b/libc/sysdeps/linux/xtensa/clone.S
index aa79aa736..34d68a875 100644
--- a/libc/sysdeps/linux/xtensa/clone.S
+++ b/libc/sysdeps/linux/xtensa/clone.S
@@ -1,34 +1,38 @@
-/* Copyright (C) 2001, 2005, 2007 Free Software Foundation, Inc.
+/* Copyright (C) 2001, 2005 Free Software Foundation, Inc.
 
    The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
 
    The GNU C Library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
+   Library General Public License for more details.
 
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
 
 /* clone is even more special than fork as it mucks with stacks
-   and invokes a function in the right context after it's all over.  */
+   and invokes a function in the right context after its all over.  */
 
-#include "sysdep.h"
-#include <sys/syscall.h>
+#include <features.h>
+#include <sysdep.h>
 #define _ERRNO_H	1
 #include <bits/errno.h>
+#ifdef RESET_PID
+#include <tls.h>
+#endif
+#define __ASSEMBLY__
+#include <linux/sched.h>
 
-/* int clone (a2 = int (*fn)(void *arg),
-	      a3 = void *child_stack,
-	      a4 = int flags,
-	      a5 = void *arg,
-              a6 = pid_t *ptid,
-	      a7 = struct user_desc *tls,
-	      16(sp) = pid_t *ctid) */
+/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
+                    a2                    a3               a4        a5
+             pid_t *ptid, struct user_desc *tls, pid_t *ctid)
+                   a6               a7              16(sp)
+*/
 
         .text
 ENTRY (__clone)
@@ -39,7 +43,7 @@ ENTRY (__clone)
 
 	/* a2 and a3 are candidates for destruction by system-call return
 	   parameters.  We don't need the stack pointer after the system
-	   call.  We trust that the kernel will preserve a7, a9, and a6.  */
+	   call.  We trust that the kernel will preserve a6, a7 and a9. */
 
 	mov	a9, a5			/* save function argument */
 	mov	a5, a7
@@ -48,19 +52,18 @@ ENTRY (__clone)
 	mov	a6, a4
 	mov	a4, a8
 	l32i	a8, a1, 16		/* child_tid */
-	movi	a2, SYS_ify (clone)
-
-	/* syscall (a2 = NR_clone,
-		    a6 = clone_flags,
-		    a3 = usp,
-		    a4 = parent_tid,
-		    a5 = child_tls,
-		    a8 = child_tid) */
+	movi	a2, SYS_ify(clone)
+
+	/* syscall(NR_clone,clone_flags, usp, parent_tid, child_tls, child_tid)
+                     a2         a6        a3        a4        a5         a8
+         */
+
 	syscall
 	bltz	a2, SYSCALL_ERROR_LABEL
 	beqz	a2, .Lthread_start
 
-	/* Fall through for parent.  */
+	/* fall through for parent */
+
 .Lpseudo_end:
 	retw
 
@@ -69,32 +72,38 @@ ENTRY (__clone)
 	j	SYSCALL_ERROR_LABEL
 
 .Lthread_start:
-	/* Start child thread.  */
-	movi	a0, 0			/* terminate the stack frame */
+
+#if CLONE_THREAD != 0x00010000 || CLONE_VM != 0x00000100
+# error invalid values for CLONE_THREAD or CLONE_VM
+#endif
 
 #ifdef RESET_PID
-	/* Check and see if we need to reset the PID.  */
-	bbsi.l	a6, 16, 1f		/* CLONE_THREAD = 0x00010000 */
+	bbsi.l	a6, 16, .Lskip_restore_pid	/* CLONE_THREAD = 0x00010000 */
 	movi	a2, -1
-	bbsi.l	a6, 8, 2f		/* CLONE_VM = 0x00000100 */
-	movi	a2, SYS_ify (getpid)
+	bbsi	a6, 8, .Lgotpid			/* CLONE_VM     = 0x00000100 */
+	movi	a2, SYS_ify(getpid)
 	syscall
-2:	rur	a3, THREADPTR
-	movi	a4, PID_OFFSET
-	add	a4, a4, a3
-	s32i	a2, a4, 0
-	movi	a4, TID_OFFSET
-	add	a4, a4, a3
-	s32i	a2, a3, 0
-1:
-#endif /* RESET_PID */
-
+.Lgotpid:
+	rur	a3, threadptr
+	movi	a0, TLS_PRE_TCB_SIZE
+	sub	a3, a3, a0
+	s32i	a2, a3, PID
+	s32i	a2, a3, TID
+.Lskip_restore_pid:
+#endif
+
+	/* start child thread */
+	movi	a0, 0			/* terminate the stack frame */
 	mov	a6, a9			/* load up the 'arg' parameter */
 	callx4	a7			/* call the user's function */
 
 	/* Call _exit.  Note that any return parameter from the user's
-	   function in a6 is seen as inputs to _exit.  */
-	movi	a2, JUMPTARGET(_exit)
+	   function in a6 is seen as inputs to _exit. */
+#ifdef	PIC
+	movi	a2, _exit@PLT
+#else
+	movi	a2, _exit
+#endif
 	callx4	a2
 
 PSEUDO_END (__clone)
diff --git a/libc/sysdeps/linux/xtensa/fork.c b/libc/sysdeps/linux/xtensa/fork.c
index e9b681c67..4e4f937a0 100644
--- a/libc/sysdeps/linux/xtensa/fork.c
+++ b/libc/sysdeps/linux/xtensa/fork.c
@@ -20,6 +20,10 @@ pid_t fork(void)
 {
 	return (pid_t) INLINE_SYSCALL(clone, 2, SIGCHLD, 0);
 }
-lt_strong_alias(fork)
-lt_libc_hidden(fork)
+# ifdef __UCLIBC_HAS_THREADS__
+strong_alias(fork,__libc_fork)
+libc_hidden_weak(fork)
+# else
+libc_hidden_def(fork)
+# endif
 #endif
diff --git a/libc/sysdeps/linux/xtensa/jmpbuf-unwind.h b/libc/sysdeps/linux/xtensa/jmpbuf-unwind.h
index 41f81dbad..4516d9398 100644
--- a/libc/sysdeps/linux/xtensa/jmpbuf-unwind.h
+++ b/libc/sysdeps/linux/xtensa/jmpbuf-unwind.h
@@ -1,25 +1,23 @@
-/* Copyright (C) 1997, 1998, 2007 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-/* Test if longjmp to JMPBUF would unwind the frame containing a local
-   variable at ADDRESS.  */
-
+/*
+ * Copyright (C) 2000-2006 Erik Andersen <andersen@uclibc.org>
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
 #include <setjmp.h>
 #include <jmpbuf-offsets.h>
 
+/* Test if longjmp to JMPBUF would unwind the frame
+   containing a local variable at ADDRESS.  */
 #define _JMPBUF_UNWINDS(jmpbuf, address) \
   ((void *) (address) < (void *) (jmpbuf)[JB_SP])
+
+#ifdef __UCLIBC_HAS_THREADS_NATIVE__
+#include <stdint.h>
+#include <unwind.h>
+
+#define _JMPBUF_CFA_UNWINDS_ADJ(_jmpbuf, _context, _adj) \
+  _JMPBUF_UNWINDS_ADJ (_jmpbuf, (void *) _Unwind_GetCFA (_context), _adj)
+
+#define _JMPBUF_UNWINDS_ADJ(_jmpbuf, _address, _adj) \
+  ((uintptr_t) (_address) - (_adj) < (uintptr_t) (_jmpbuf)[JB_SP] - (_adj))
+#endif
diff --git a/libc/sysdeps/linux/xtensa/sys/ptrace.h b/libc/sysdeps/linux/xtensa/sys/ptrace.h
new file mode 100644
index 000000000..882b8c8ed
--- /dev/null
+++ b/libc/sysdeps/linux/xtensa/sys/ptrace.h
@@ -0,0 +1,155 @@
+/* `ptrace' debugger support interface.  Linux version.
+   Copyright (C) 1996, 1997, 1998, 1999, 2000, 2007
+   Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_PTRACE_H
+#define _SYS_PTRACE_H	1
+
+#include <features.h>
+
+/* Kludge away careless namespace pollution from the kernel. */
+
+#undef PTRACE_GETREGS
+#undef PTRACE_SETREGS
+#undef PTRACE_GETFPREGS
+#undef PTRACE_SETFPREGS
+#undef PTRACE_GETFPREGSIZE
+
+
+__BEGIN_DECLS
+
+/* Type of the REQUEST argument to `ptrace.'  */
+enum __ptrace_request
+{
+  /* Indicate that the process making this request should be traced.
+     All signals received by this process can be intercepted by its
+     parent, and its parent can use the other `ptrace' requests.  */
+  PTRACE_TRACEME = 0,
+#define PT_TRACE_ME PTRACE_TRACEME
+
+  /* Return the word in the process's text space at address ADDR.  */
+  PTRACE_PEEKTEXT = 1,
+#define PT_READ_I PTRACE_PEEKTEXT
+
+  /* Return the word in the process's data space at address ADDR.  */
+  PTRACE_PEEKDATA = 2,
+#define PT_READ_D PTRACE_PEEKDATA
+
+  /* Return the word in the process's user area at offset ADDR.  */
+  PTRACE_PEEKUSER = 3,
+#define PT_READ_U PTRACE_PEEKUSER
+
+  /* Write the word DATA into the process's text space at address ADDR.  */
+  PTRACE_POKETEXT = 4,
+#define PT_WRITE_I PTRACE_POKETEXT
+
+  /* Write the word DATA into the process's data space at address ADDR.  */
+  PTRACE_POKEDATA = 5,
+#define PT_WRITE_D PTRACE_POKEDATA
+
+  /* Write the word DATA into the process's user area at offset ADDR.  */
+  PTRACE_POKEUSER = 6,
+#define PT_WRITE_U PTRACE_POKEUSER
+
+  /* Continue the process.  */
+  PTRACE_CONT = 7,
+#define PT_CONTINUE PTRACE_CONT
+
+  /* Kill the process.  */
+  PTRACE_KILL = 8,
+#define PT_KILL PTRACE_KILL
+
+  /* Single step the process.
+     This is not supported on all machines.  */
+  PTRACE_SINGLESTEP = 9,
+#define PT_STEP PTRACE_SINGLESTEP
+
+  /* Get all general purpose registers used by a processes.
+     This is not supported on all machines.  */
+   PTRACE_GETREGS = 12,
+#define PT_GETREGS PTRACE_GETREGS
+
+  /* Set all general purpose registers used by a processes.
+     This is not supported on all machines.  */
+   PTRACE_SETREGS = 13,
+#define PT_SETREGS PTRACE_SETREGS
+
+  /* Get all floating point registers used by a processes.
+     This is not supported on all machines.  */
+   PTRACE_GETFPREGS = 14,
+#define PT_GETFPREGS PTRACE_GETFPREGS
+
+  /* Set all floating point registers used by a processes.
+     This is not supported on all machines.  */
+   PTRACE_SETFPREGS = 15,
+#define PT_SETFPREGS PTRACE_SETFPREGS
+
+  /* Attach to a process that is already running. */
+  PTRACE_ATTACH = 16,
+#define PT_ATTACH PTRACE_ATTACH
+
+  /* Detach from a process attached to with PTRACE_ATTACH.  */
+  PTRACE_DETACH = 17,
+#define PT_DETACH PTRACE_DETACH
+
+  /* Get size required for the buffer holding the floating point registers.
+     This is not supported on all machines.  */
+   PTRACE_GETFPREGSIZE = 18,
+#define PT_GETFPREGSIZE PTRACE_GETFPREGSIZE
+
+  /* Continue and stop at the next (return from) syscall.  */
+  PTRACE_SYSCALL = 24
+#define PT_SYSCALL PTRACE_SYSCALL
+};
+
+/* Options set using PTRACE_SETOPTIONS.  */
+enum __ptrace_setoptions {
+  PTRACE_O_TRACESYSGOOD	= 0x00000001,
+  PTRACE_O_TRACEFORK	= 0x00000002,
+  PTRACE_O_TRACEVFORK   = 0x00000004,
+  PTRACE_O_TRACECLONE	= 0x00000008,
+  PTRACE_O_TRACEEXEC	= 0x00000010,
+  PTRACE_O_TRACEVFORKDONE = 0x00000020,
+  PTRACE_O_TRACEEXIT	= 0x00000040,
+  PTRACE_O_MASK		= 0x0000007f
+};
+
+/* Wait extended result codes for the above trace options.  */
+enum __ptrace_eventcodes {
+  PTRACE_EVENT_FORK	= 1,
+  PTRACE_EVENT_VFORK	= 2,
+  PTRACE_EVENT_CLONE	= 3,
+  PTRACE_EVENT_EXEC	= 4,
+  PTRACE_EVENT_VFORK_DONE = 5,
+  PTRACE_EVENT_EXIT	= 6
+};
+
+/* Perform process tracing functions.  REQUEST is one of the values
+   above, and determines the action to be taken.
+   For all requests except PTRACE_TRACEME, PID specifies the process to be
+   traced.
+
+   PID and the other arguments described above for the various requests should
+   appear (those that are used for the particular request) as:
+     pid_t PID, void *ADDR, int DATA, void *ADDR2
+   after REQUEST.  */
+extern long int ptrace (enum __ptrace_request __request, ...) __THROW;
+
+__END_DECLS
+
+#endif /* _SYS_PTRACE_H */
diff --git a/libc/sysdeps/linux/xtensa/sysdep.h b/libc/sysdeps/linux/xtensa/sysdep.h
index afe95cc6a..cab4a2f8d 100644
--- a/libc/sysdeps/linux/xtensa/sysdep.h
+++ b/libc/sysdeps/linux/xtensa/sysdep.h
@@ -16,6 +16,10 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#ifndef _LINUX_XTENSA_SYSDEP_H
+#define _LINUX_XTENSA_SYSDEP_H 1
+
+#include <common/sysdep.h>
 #include <sys/syscall.h>
 
 #ifdef __ASSEMBLER__
@@ -24,12 +28,6 @@
 #define ASM_TYPE_DIRECTIVE(name, typearg) .type name, typearg
 #define ASM_SIZE_DIRECTIVE(name) .size name, . - name
 
-#ifdef __STDC__
-#define C_LABEL(name)	name :
-#else
-#define C_LABEL(name)	name/**/:
-#endif
-
 #define	ENTRY(name)							\
   ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);				\
   ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name), @function);			\
@@ -52,6 +50,15 @@
 #undef END
 #define END(name) ASM_SIZE_DIRECTIVE(name)
 
+/* Local label name for asm code. */
+#ifndef L
+# ifdef HAVE_ELF
+#  define L(name)       .L##name
+# else
+#  define L(name)       name
+# endif
+#endif
+
 /* Define a macro for this directive so it can be removed in a few places.  */
 #define LITERAL_POSITION .literal_position
 
@@ -123,19 +130,7 @@
 #define	PSEUDO_END_ERRVAL(name)						      \
   END (name)
 
-#undef ret_ERRVAL
-#define ret_ERRVAL retw
-
-#if defined RTLD_PRIVATE_ERRNO
-# define SYSCALL_ERROR_HANDLER						      \
-0:	movi	a4, rtld_errno;						      \
-	neg	a2, a2;							      \
-	s32i	a2, a4, 0;						      \
-	movi	a2, -1;							      \
-	j	.Lpseudo_end;
-
-#elif defined _LIBC_REENTRANT
-
+#if defined _LIBC_REENTRANT
 # if defined USE___THREAD
 #  ifndef NOT_IN_libc
 #   define SYSCALL_ERROR_ERRNO __libc_errno
@@ -170,3 +165,9 @@
 #endif /* _LIBC_REENTRANT */
 
 #endif	/* __ASSEMBLER__ */
+
+/* Pointer mangling is not yet supported for Xtensa.  */
+#define PTR_MANGLE(var) (void) (var)
+#define PTR_DEMANGLE(var) (void) (var)
+
+#endif	/* _LINUX_XTENSA_SYSDEP_H */
diff --git a/libc/sysdeps/linux/xtensa/vfork.S b/libc/sysdeps/linux/xtensa/vfork.S
index f094ae38f..6aced0a50 100644
--- a/libc/sysdeps/linux/xtensa/vfork.S
+++ b/libc/sysdeps/linux/xtensa/vfork.S
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005, 2007 Free Software Foundation, Inc.
+/* Copyright (C) 2005-2013 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -19,72 +19,67 @@
 #include <sys/syscall.h>
 #define _SIGNAL_H
 #include <bits/signum.h>
+#define __ASSEMBLY__
+#include <linux/sched.h>
 
 
-/* Clone the calling process, but without copying the whole address space.
+/*
+   Clone the calling process, but without copying the whole address space.
    The calling process is suspended until the new process exits or is
    replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
    and the process ID of the new process to the old process.
 
    Note that it is important that we don't create a new stack frame for the
-   caller.  */
+   caller.
 
-
-/* The following are defined in linux/sched.h, which unfortunately
-   is not safe for inclusion in an assembly file.  */
-#define CLONE_VM        0x00000100     /* set if VM shared between processes */
-#define CLONE_VFORK     0x00004000     /* set if the parent wants the child to
-					  wake it up on mm_release */
+*/
 
 #ifndef SAVE_PID
-#define SAVE_PID
+#define SAVE_PID(a,b,c,d)
 #endif
-
 #ifndef RESTORE_PID
-#define RESTORE_PID
+#define RESTORE_PID(a,b,c)
+#endif
+#ifndef RESTORE_PID12
+#define RESTORE_PID12(a,b,c)
 #endif
 
+/*
+   pid_t vfork(void);
+   Implemented as __clone_syscall(CLONE_VFORK | CLONE_VM | SIGCHLD, 0)
+ */
 
-/* pid_t vfork(void);
-   Implemented as __clone_syscall(CLONE_VFORK | CLONE_VM | SIGCHLD, 0) */
 
 HIDDEN_ENTRY (__vfork)
+        .literal .Ljumptable, 0, .L4, .L8, .L12
 
-	movi	a6, .Ljumptable
-	extui	a2, a0, 30, 2		/* call-size: call4/8/12 = 1/2/3 */
-	addx4	a4, a2, a6		/* find return address in jumptable */
-	l32i	a4, a4, 0
-	add	a4, a4, a6
-
+	mov	a3, a0			# move return address out of the way
+	movi	a0, .Ljumptable
+	extui	a2, a3, 30, 2		# call-size: call4/8/12 = 1/2/3
+	addx4	a0, a2, a0		# find return address in jumptable
 	slli	a2, a2, 30
-	xor	a3, a0, a2		/* remove call-size from return addr */
-	extui	a5, a4, 30, 2		/* get high bits of jump target */
-	slli	a5, a5, 30
-	or	a3, a3, a5		/* stuff them into the return address */
-	xor	a4, a4, a5		/* clear high bits of jump target */
-	or	a0, a4, a2		/* create temporary return address */
-	retw				/* "return" to .L4, .L8, or .L12 */
-
-	.align	4
-.Ljumptable:
-	.word	0
-	.word	.L4 - .Ljumptable
-	.word	.L8 - .Ljumptable
-	.word	.L12 - .Ljumptable
+	l32i	a0, a0, 0
+
+	xor	a3, a3, a2		# remove call-size from return address
+	or	a0, a0, a2		# create temporary return address
+	retw
 
 	/* a7: return address */
+
 .L4:	mov	a12, a2
 	mov	a13, a3
 
-	SAVE_PID
+	SAVE_PID(a5,a15,a2,a3)
+
+	/* use syscall 'clone' and set new stack pointer to the same address */
 
-	/* Use syscall 'clone'.  Set new stack pointer to the same address.  */
-	movi	a2, SYS_ify (clone)
+	movi	a2, SYS_ify(clone)
 	movi	a3, 0
 	movi	a6, CLONE_VM | CLONE_VFORK | SIGCHLD
+
         syscall
 
-	RESTORE_PID
+	RESTORE_PID(a5,a15,a2)
 
 	movi	a5, -4096
 
@@ -94,22 +89,24 @@ HIDDEN_ENTRY (__vfork)
 
 	bgeu	a6, a5, 1f
 	jx	a7
-1:	call4	.Lerr			/* returns to original caller */
 
+1:	call4	.Lerr
 
 	/* a11: return address */
+
 .L8:	mov	a12, a2
 	mov	a13, a3
 	mov	a14, a6
 
-	SAVE_PID
+	SAVE_PID(a9,a15,a2,a3)
 
-	movi	a2, SYS_ify (clone)
+	movi	a2, SYS_ify(clone)
 	movi	a3, 0
 	movi	a6, CLONE_VM | CLONE_VFORK | SIGCHLD
+
 	syscall
 
-	RESTORE_PID
+	RESTORE_PID(a9,a15,a2)
 
 	movi	a9, -4096
 
@@ -120,22 +117,25 @@ HIDDEN_ENTRY (__vfork)
 
 	bgeu	a10, a9, 1f
 	jx	a11
-1:	call8	.Lerr			/* returns to original caller */
+
+1:	call8	.Lerr
 
 
 	/* a15: return address */
+
 .L12:	mov	a12, a2
 	mov	a13, a3
 	mov	a14, a6
 
-	SAVE_PID
+	SAVE_PID (a2,a3,a2,a6)
 
-	movi	a2, SYS_ify (clone)
+	movi	a2, SYS_ify(clone)
 	movi	a3, 0
 	movi	a6, CLONE_VM | CLONE_VFORK | SIGCHLD
+
 	syscall
 
-	RESTORE_PID
+	RESTORE_PID12(a3,a6,a15)
 
 	mov	a3, a13
 	movi	a13, -4096
@@ -147,18 +147,18 @@ HIDDEN_ENTRY (__vfork)
 
 	bgeu	a14, a13, 1f
 	jx	a15
-1:	call12	.Lerr			/* returns to original caller */
 
+1:	call12	.Lerr
 
 	.align 4
+
 .Lerr:	entry	a1, 16
 
-	/* Restore the return address.  */
-	extui	a4, a0, 30, 2		/* get the call-size bits */
+	/* Restore return address */
+
+	extui	a4, a0, 30, 2
 	slli	a4, a4, 30
-	slli	a3, a3, 2		/* clear high bits of target address */
-	srli	a3, a3, 2
-	or	a0, a3, a4		/* combine them */
+	or	a0, a3, a4
 
 	PSEUDO_END (__vfork)
 .Lpseudo_end: