This is the mail archive of the libc-hacker@sourceware.org mailing list for the glibc project.

Note that libc-hacker is a closed list. You may look at the archives of this list, but subscription and posting are not open.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[PATCH] sparc setjmp/longjmp mangling


Hi!

Pointer mangling for sparc{32,64} and setjmp/longjmp mangling on sparc32.
On sparc64, setjmp/longjmp are syscalls (well, actually just traps into
kernel), so mangling isn't (easily) feasible there.

2006-01-02  Jakub Jelinek  <jakub@redhat.com>

	* sysdeps/unix/sysv/linux/sparc/sparc32/sysdep.h (PTR_MANGLE,
	PTR_MANGLE2, PTR_DEMANGLE, PTR_DEMANGLE2): Define.
	* sysdeps/unix/sysv/linux/sparc/sparc64/sysdep.h (PTR_MANGLE,
	PTR_MANGLE2, PTR_DEMANGLE, PTR_DEMANGLE2): Define.
	* sysdeps/unix/sysv/linux/sparc/bits/setjmp.h [__WORDSIZE == 64]
	(_JMPBUF_UNWINDS): Don't demangle uc_mcontext.mc_fp.
	* sysdeps/sparc/sparc32/setjmp.S (__sigsetjmp): Mangle %fp, %sp
	and %o7.
	* sysdeps/sparc/sparc32/__longjmp.S (__longjmp): Demangle %fp, %sp
	and %o7.
nptl/
	* sysdeps/sparc/tls.h (tcbhead_t): Add pointer_guard field.
	(THREAD_GET_POINTER_GUARD, THREAD_SET_POINTER_GUARD,
	THREAD_COPY_POINTER_GUARD): Define.
	* sysdeps/sparc/tcb-offsets.sym (POINTER_GUARD): Define.
	* sysdeps/sparc/sparc64/jmpbuf-unwind.h: Revert 2005-12-27 changes.

--- libc/sysdeps/unix/sysv/linux/sparc/sparc32/sysdep.h.jj	2004-10-05 03:05:02.000000000 -0400
+++ libc/sysdeps/unix/sysv/linux/sparc/sparc32/sysdep.h	2006-01-02 06:45:25.000000000 -0500
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997, 2002, 2003, 2004 Free Software Foundation, Inc.
+/* Copyright (C) 1997, 2002, 2003, 2004, 2006 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Miguel de Icaza <miguel@gnu.ai.mit.edu>, January 1997.
 
@@ -214,4 +214,24 @@ SYSCALL_ERROR_HANDLER_ENTRY(__syscall_er
 
 #endif	/* __ASSEMBLER__ */
 
+/* Pointer mangling support.  */
+#if defined NOT_IN_libc && defined IS_IN_rtld
+/* We cannot use the thread descriptor because in ld.so we use setjmp
+   earlier than the descriptor is initialized.  */
+#else
+# ifdef __ASSEMBLER__
+#  define PTR_MANGLE(dreg, reg, tmpreg) \
+  ld	[%g7 + POINTER_GUARD], tmpreg; \
+  xor	reg, tmpreg, dreg
+#  define PTR_DEMANGLE(dreg, reg, tmpreg) PTR_MANGLE (dreg, reg, tmpreg)
+#  define PTR_MANGLE2(dreg, reg, tmpreg) \
+  xor	reg, tmpreg, dreg
+#  define PTR_DEMANGLE2(dreg, reg, tmpreg) PTR_MANGLE2 (dreg, reg, tmpreg)
+# else
+#  define PTR_MANGLE(var) \
+  (var) = (__typeof (var)) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ())
+#  define PTR_DEMANGLE(var)     PTR_MANGLE (var)
+# endif
+#endif
+
 #endif /* linux/sparc/sysdep.h */
--- libc/sysdeps/unix/sysv/linux/sparc/sparc64/sysdep.h.jj	2005-06-06 08:36:17.000000000 -0400
+++ libc/sysdeps/unix/sysv/linux/sparc/sparc64/sysdep.h	2006-01-02 06:45:25.000000000 -0500
@@ -240,4 +240,24 @@ SYSCALL_ERROR_HANDLER_ENTRY(__syscall_er
    register windows.  So if you poke stack memory directly you add this.  */
 #define STACK_BIAS	2047
 
+/* Pointer mangling support.  */
+#if defined NOT_IN_libc && defined IS_IN_rtld
+/* We cannot use the thread descriptor because in ld.so we use setjmp
+   earlier than the descriptor is initialized.  */
+#else
+# ifdef __ASSEMBLER__
+#  define PTR_MANGLE(dreg, reg, tmpreg) \
+  ldx	[%g7 + POINTER_GUARD], tmpreg; \
+  xor	reg, tmpreg, dreg
+#  define PTR_DEMANGLE(dreg, reg, tmpreg) PTR_MANGLE (dreg, reg, tmpreg)
+#  define PTR_MANGLE2(dreg, reg, tmpreg) \
+  xor	reg, tmpreg, dreg
+#  define PTR_DEMANGLE2(dreg, reg, tmpreg) PTR_MANGLE2 (dreg, reg, tmpreg)
+# else
+#  define PTR_MANGLE(var) \
+  (var) = (__typeof (var)) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ())
+#  define PTR_DEMANGLE(var)     PTR_MANGLE (var)
+# endif
+#endif
+
 #endif /* linux/sparc64/sysdep.h */
--- libc/sysdeps/unix/sysv/linux/sparc/bits/setjmp.h.jj	2005-12-30 03:04:17.000000000 -0500
+++ libc/sysdeps/unix/sysv/linux/sparc/bits/setjmp.h	2006-01-02 06:45:25.000000000 -0500
@@ -1,4 +1,5 @@
-/* Copyright (C) 1997,1999,2000,2003, 2005 Free Software Foundation, Inc.
+/* Copyright (C) 1997, 1999, 2000, 2003, 2005, 2006
+   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
@@ -60,7 +61,7 @@ typedef struct __sparc64_jmp_buf
 /* Test if longjmp to JMPBUF would unwind the frame
    containing a local variable at ADDRESS.  */
 #define _JMPBUF_UNWINDS(jmpbuf, address, demangle)			\
-  ((unsigned long int) (address) < demangle ((jmpbuf)->uc_mcontext.mc_fp))
+  ((unsigned long int) (address) < (jmpbuf)->uc_mcontext.mc_fp)
 
 #else
 
--- libc/sysdeps/sparc/sparc32/setjmp.S.jj	2002-12-31 15:37:25.000000000 -0500
+++ libc/sysdeps/sparc/sparc32/setjmp.S	2006-01-02 06:45:25.000000000 -0500
@@ -1,4 +1,5 @@
-/* Copyright (C) 1991, 93, 94, 96, 97, 98, 2002 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 1993, 1994, 1996, 1997, 1998, 2002, 2006
+   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
@@ -39,9 +40,18 @@ ENTRY (__sigsetjmp)
 	   a tail-call for simplicity; it always returns zero.  */
 	ta	ST_FLUSH_WINDOWS
 
+#ifdef PTR_MANGLE
+	PTR_MANGLE (%g1, %o7, %g4)
+	PTR_MANGLE2 (%g2, %sp, %g4)
+	PTR_MANGLE2 (%g3, %fp, %g4)
+	st	%g1, [%o0 + (JB_PC * 4)]
+	st	%g2, [%o0 + (JB_SP * 4)]
+	st	%g3, [%o0 + (JB_FP * 4)]
+#else
 	st	%o7, [%o0 + (JB_PC * 4)]
 	st	%sp, [%o0 + (JB_SP * 4)]
 	st	%fp, [%o0 + (JB_FP * 4)]
+#endif
 
 	mov	%o7, %g1
 	call	__sigjmp_save
--- libc/sysdeps/sparc/sparc32/__longjmp.S.jj	2001-07-06 00:56:04.000000000 -0400
+++ libc/sysdeps/sparc/sparc32/__longjmp.S	2006-01-02 06:45:25.000000000 -0500
@@ -1,4 +1,5 @@
-/* Copyright (C) 1991, 93, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 1993, 1996, 1997, 1998, 1999, 2000, 2006
+   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
@@ -30,6 +31,9 @@ ENTRY(__longjmp)
 	   use them while unwinding frames and their register windows.  */
 
 	ld ENV(o0,JB_FP), %g3	/* Cache target FP in register %g3.  */
+#ifdef PTR_DEMANGLE
+	PTR_DEMANGLE (%g3, %g3, %g4)
+#endif
 	mov %o0, %g1		/* ENV in %g1 */
      	orcc %o1, %g0, %g2	/* VAL in %g2 */
      	be,a 0f			/* Branch if zero; else skip delay slot.  */
@@ -62,8 +66,15 @@ LOC(thread):
 	 * windows.
 	 */
 	ta	ST_FLUSH_WINDOWS
+#ifdef PTR_DEMANGLE
+	ld	ENV(g1,JB_PC), %g5 /* Set return PC. */
+	ld	ENV(g1,JB_SP), %g1 /* Set saved SP on restore below. */
+	PTR_DEMANGLE2 (%o7, %g5, %g4)
+	PTR_DEMANGLE2 (%fp, %g1, %g4)
+#else
 	ld	ENV(g1,JB_PC), %o7 /* Set return PC. */
 	ld	ENV(g1,JB_SP), %fp /* Set saved SP on restore below. */
+#endif
 	sub	%fp, 64, %sp	/* Allocate a register frame. */
 	st	%g3, RW_FP	/* Set saved FP on restore below. */
 	retl
@@ -71,10 +82,17 @@ LOC(thread):
 
 LOC(found):
 	/* We have unwound register windows so %fp matches the target.  */
+#ifdef PTR_DEMANGLE
+	PTR_DEMANGLE2 (%sp, %o0, %g4)
+#else
 	mov %o0, %sp		/* OK, install new SP.  */
+#endif
 
 LOC(sp_ok):
 	ld ENV(g1,JB_PC), %o0	/* Extract target return PC.  */
+#ifdef PTR_DEMANGLE
+	PTR_DEMANGLE2 (%o0, %o0, %g4)
+#endif
 	jmp %o0 + 8		/* Return there.  */
 	 mov %g2, %o0		/* Delay slot: set return value.  */
 
--- libc/nptl/sysdeps/sparc/sparc64/jmpbuf-unwind.h.jj	2005-12-30 03:04:04.000000000 -0500
+++ libc/nptl/sysdeps/sparc/sparc64/jmpbuf-unwind.h	2006-01-02 06:45:25.000000000 -0500
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Free Software Foundation, Inc.
+/* Copyright (C) 2005, 2006 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by David S. Miller <davem@davemloft.net>, 2005.
 
@@ -20,23 +20,12 @@
 #include <setjmp.h>
 #include <stdint.h>
 #include <unwind.h>
-#include <sysdep.h>
 
 #define _JMPBUF_CFA_UNWINDS_ADJ(_jmpbuf, _context, _adj) \
   _JMPBUF_UNWINDS_ADJ (_jmpbuf, (void *) _Unwind_GetCFA (_context), _adj)
 
-static inline uintptr_t __attribute__ ((unused))
-_jmpbuf_sp (__jmp_buf regs)
-{
-  uintptr_t sp = regs[0].uc_mcontext.mc_fp;
-#ifdef PTR_DEMANGLE
-  PTR_DEMANGLE (sp);
-#endif
-  return sp;
-}
-
 #define _JMPBUF_UNWINDS_ADJ(_jmpbuf, _address, _adj) \
-  ((uintptr_t) (_address) - (_adj) < _jmpbuf_sp (_jmpbuf) - (_adj))
+  ((uintptr_t) (_address) - (_adj) < (uintptr_t) (_jmpbuf)[0].uc_mcontext.mc_fp - (_adj))
 
 /* We use the normal lobngjmp for unwinding.  */
 #define __libc_unwind_longjmp(buf, val) __libc_longjmp (buf, val)
--- libc/nptl/sysdeps/sparc/tcb-offsets.sym.jj	2004-12-21 08:33:31.000000000 -0500
+++ libc/nptl/sysdeps/sparc/tcb-offsets.sym	2006-01-02 06:45:25.000000000 -0500
@@ -2,5 +2,6 @@
 #include <tls.h>
 
 MULTIPLE_THREADS_OFFSET		offsetof (tcbhead_t, multiple_threads)
+POINTER_GUARD			offsetof (tcbhead_t, pointer_guard)
 PID				offsetof (struct pthread, pid)
 TID				offsetof (struct pthread, tid)
--- libc/nptl/sysdeps/sparc/tls.h.jj	2005-08-23 06:00:43.000000000 -0400
+++ libc/nptl/sysdeps/sparc/tls.h	2006-01-02 10:26:11.000000000 -0500
@@ -1,5 +1,5 @@
 /* Definitions for thread-local data handling.  NPTL/sparc version.
-   Copyright (C) 2003, 2005 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2005, 2006 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
@@ -48,6 +48,7 @@ typedef struct
   int multiple_threads;
   uintptr_t sysinfo;
   uintptr_t stack_guard;
+  uintptr_t pointer_guard;
 } tcbhead_t;
 
 #else /* __ASSEMBLER__ */
@@ -135,6 +136,14 @@ register struct pthread *__thread_self _
   ((descr)->header.stack_guard \
    = THREAD_GETMEM (THREAD_SELF, header.stack_guard))
 
+/* Get/set the stack guard field in TCB head.  */
+#define THREAD_GET_POINTER_GUARD() \
+  THREAD_GETMEM (THREAD_SELF, header.pointer_guard)
+#define THREAD_SET_POINTER_GUARD(value) \
+  THREAD_SETMEM (THREAD_SELF, header.pointer_guard, value)
+# define THREAD_COPY_POINTER_GUARD(descr) \
+  ((descr)->header.pointer_guard = THREAD_GET_POINTER_GUARD ())
+
 #endif /* !ASSEMBLER */
 
 #endif	/* tls.h */

	Jakub


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]