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PATCH: BPs for ix86 setjmp/longjmp


build-shared and build-static successful for i686.

No binary differences.

OK?

2000-06-29  Greg McGary  <greg@mcgary.org>

	* sysdeps/i386/bp-asm.h (PCOFF): New constant.
	(POP_ERRNO_LOCATION_RETURN): Fold insns.
	* sysdeps/i386/bits/setjmp.h (JB_SIZE): New constant.
	(PUSH_SIGNAL_MASK): New macro.
	* sysdeps/i386/__longjmp.S (__longjmp): Wrap symbol in BP_SYM ().
	LEAVE is unnecessary.  Check bounds of jmp_buf.
	* sysdeps/i386/elf/setjmp.S: Call PUSH_SIGNAL_MASK.
	Wrap symbols in BP_SYM ().  Check bounds of jmp_buf.
	Don't call LEAVE until immediately before tail-call.
	* sysdeps/i386/setjmp.S: Likewise.
	* sysdeps/i386/bsd-_setjmp.S: Likewise.
	* sysdeps/i386/bsd-setjmp.S: Likewise.

Index: sysdeps/i386/__longjmp.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/__longjmp.S,v
retrieving revision 1.9
diff -u -p -r1.9 __longjmp.S
--- __longjmp.S	2000/06/09 06:14:38	1.9
+++ __longjmp.S	2000/06/29 22:38:49
@@ -21,17 +21,19 @@
 #define _ASM
 #define _SETJMP_H
 #include <bits/setjmp.h>
+#include <asm-syntax.h>
+#include <bp-sym.h>
 #include <bp-asm.h>
 
 #define PARMS	LINKAGE		/* no space for saved regs */
 #define JBUF	PARMS
 #define VAL	JBUF+PTR_SIZE
 
-ENTRY (__longjmp)
+ENTRY (BP_SYM (__longjmp))
 	ENTER
 
 	movl JBUF(%esp), %ecx	/* User's jmp_buf in %ecx.  */
-	LEAVE
+	CHECK_BOUNDS_BOTH_WIDE (%ecx, JBUF(%esp), $JB_SIZE)
 
 	movl VAL(%esp), %eax	/* Second argument is return value.  */
 	/* Save the return address now.  */
@@ -44,4 +46,4 @@ ENTRY (__longjmp)
 	movl (JB_SP*4)(%ecx), %esp
 	/* Jump to saved PC.  */
      	jmp *%edx
-END (__longjmp)
+END (BP_SYM (__longjmp))
Index: sysdeps/i386/bp-asm.h
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/bp-asm.h,v
retrieving revision 1.1
diff -u -p -r1.1 bp-asm.h
--- bp-asm.h	2000/06/09 06:14:39	1.1
+++ bp-asm.h	2000/06/29 22:38:49
@@ -43,6 +43,8 @@
 /* Stack space overhead of procedure-call linkage: return address and
    frame pointer.  */
 #   define LINKAGE 8
+/* Stack offset of return address after calling ENTER.  */
+#   define PCOFF 4
 
 /* Int 5 is the "bound range" exception also raised by the "bound"
    instruction.  */
@@ -106,8 +108,7 @@
    argument, but we must pop the space for the BP itself.  We also
    dereference the return value in order to dig out the pointer value.  */
 #   define POP_ERRNO_LOCATION_RETURN		\
-	movl (%esp), %eax;			\
-	addl $4, %esp;				\
+	popl %eax;				\
 	addl $8, %esp
 
 #  else /* !__BOUNDED_POINTERS__ */
@@ -123,6 +124,8 @@
 #   define LEAVE
 /* Stack space overhead of procedure-call linkage: return address only.  */
 #   define LINKAGE 4
+/* Stack offset of return address after calling ENTER.  */
+#   define PCOFF 0
 
 #   define CHECK_BOUNDS_LOW(VAL_REG, BP_MEM)
 #   define CHECK_BOUNDS_HIGH(VAL_REG, BP_MEM, Jcc)
Index: sysdeps/i386/bsd-_setjmp.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/bsd-_setjmp.S,v
retrieving revision 1.6
diff -u -p -r1.6 bsd-_setjmp.S
--- bsd-_setjmp.S	1997/03/20 02:14:01	1.6
+++ bsd-_setjmp.S	2000/06/29 22:38:49
@@ -1,5 +1,5 @@
 /* BSD `_setjmp' entry point to `sigsetjmp (..., 0)'.  i386 version.
-   Copyright (C) 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
+   Copyright (C) 1994, 1995, 1996, 1997, 2000 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
@@ -22,13 +22,14 @@
    in setjmp doesn't clobber the state restored by longjmp.  */
 
 #include <sysdep.h>
+#define _ASM
+#define _SETJMP_H
+#include <bits/setjmp.h>
+#include "bp-sym.h"
+#include "bp-asm.h"
 
-ENTRY (_setjmp)
-	popl %eax		/* Pop return PC.  */
-	popl %ecx		/* Pop jmp_buf argument.  */
-	pushl $0		/* Push second argument of zero.  */
-	pushl %ecx		/* Push back first argument.  */
-	pushl %eax		/* Push back return PC.  */
+ENTRY (BP_SYM (_setjmp))
+	PUSH_SIGNAL_MASK (0)
 #ifdef	PIC
 	/* We cannot use the PLT, because it requires that %ebx be set, but
            we can't save and restore our caller's value.  Instead, we do an
@@ -37,9 +38,9 @@ ENTRY (_setjmp)
 	call here
 here:	popl %ecx
 	addl $_GLOBAL_OFFSET_TABLE_+[.-here], %ecx
-	movl C_SYMBOL_NAME(__sigsetjmp@GOT)(%ecx), %ecx
+	movl C_SYMBOL_NAME (BP_SYM (__sigsetjmp)@GOT)(%ecx), %ecx
 	jmp *%ecx
 #else
-	jmp __sigsetjmp
+	jmp BP_SYM (__sigsetjmp)
 #endif
-END (_setjmp)
+END (BP_SYM (_setjmp))
Index: sysdeps/i386/bsd-setjmp.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/bsd-setjmp.S,v
retrieving revision 1.5
diff -u -p -r1.5 bsd-setjmp.S
--- bsd-setjmp.S	1997/03/20 02:14:04	1.5
+++ bsd-setjmp.S	2000/06/29 22:38:49
@@ -1,5 +1,5 @@
 /* BSD `setjmp' entry point to `sigsetjmp (..., 1)'.  i386 version.
-   Copyright (C) 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
+   Copyright (C) 1994, 1995, 1996, 1997, 2000 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
@@ -22,13 +22,14 @@
    in setjmp doesn't clobber the state restored by longjmp.  */
 
 #include <sysdep.h>
+#define _ASM
+#define _SETJMP_H
+#include <bits/setjmp.h>
+#include "bp-sym.h"
+#include "bp-asm.h"
 
-ENTRY (setjmp)
-	popl %eax		/* Pop return PC.  */
-	popl %ecx		/* Pop jmp_buf argument.  */
-	pushl $1		/* Push second argument of one.  */
-	pushl %ecx		/* Push back first argument.  */
-	pushl %eax		/* Push back return PC.  */
+ENTRY (BP_SYM (setjmp))
+	PUSH_SIGNAL_MASK (1)
 #ifdef	PIC
 	/* We cannot use the PLT, because it requires that %ebx be set, but
            we can't save and restore our caller's value.  Instead, we do an
@@ -37,9 +38,9 @@ ENTRY (setjmp)
 	call here
 here:	popl %ecx
 	addl $_GLOBAL_OFFSET_TABLE_+[.-here], %ecx
-	movl C_SYMBOL_NAME(__sigsetjmp@GOT)(%ecx), %ecx
+	movl C_SYMBOL_NAME (BP_SYM (__sigsetjmp)@GOT)(%ecx), %ecx
 	jmp *%ecx
 #else
-	jmp __sigsetjmp
+	jmp BP_SYM (__sigsetjmp)
 #endif
-END (setjmp)
+END (BP_SYM (setjmp))
Index: sysdeps/i386/setjmp.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/setjmp.S,v
retrieving revision 1.10
diff -u -p -r1.10 setjmp.S
--- setjmp.S	1998/04/20 18:32:48	1.10
+++ setjmp.S	2000/06/29 22:38:49
@@ -1,5 +1,5 @@
 /* setjmp for i386.
-   Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
+   Copyright (C) 1995, 1996, 1997, 2000 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
@@ -19,29 +19,38 @@
 
 #include <sysdep.h>
 #define _ASM
+#define _SETJMP_H
 #include <bits/setjmp.h>
 #include <asm-syntax.h>
+#include "bp-sym.h"
+#include "bp-asm.h"
 
 	/* Binary compatibility entry point.  */
-ENTRY (__setjmp)
-	popl %eax		/* Pop return address.  */
-	popl %ecx		/* Pop jmp_buf.  */
-	pushl $0		/* Push zero argument.  */
-	pushl %ecx		/* Push jmp_buf.  */
-	pushl %eax		/* Push back return address.  */
+ENTRY (BP_SYM (__setjmp))
+	PUSH_SIGNAL_MASK (0)
+	/* FALL THROUGH */
+
+#define PARMS	LINKAGE		/* no space for saved regs */
+#define JMPBUF	PARMS
+#define SIGMSK	JMPBUF+PTR_SIZE
 
-ENTRY (__sigsetjmp)
-	movl 4(%esp), %eax	/* User's jmp_buf in %eax.  */
+ENTRY (BP_SYM (__sigsetjmp))
+	ENTER
+
+	movl JMPBUF(%esp), %eax
+	CHECK_BOUNDS_BOTH_WIDE (%eax, JMPBUF(%esp), $JB_SIZE)
+
      	/* Save registers.  */
 	movl %ebx, (JB_BX*4)(%eax)
 	movl %esi, (JB_SI*4)(%eax)
 	movl %edi, (JB_DI*4)(%eax)
 	movl %ebp, (JB_BP*4)(%eax)
-	leal 4(%esp), %ecx	/* Save SP as it will be after we return.  */
+	leal JMPBUF(%esp), %ecx	/* Save SP as it will be after we return.  */
      	movl %ecx, (JB_SP*4)(%eax)
-	movl 0(%esp), %ecx	/* Save PC we are returning to now.  */
+	movl PCOFF(%esp), %ecx	/* Save PC we are returning to now.  */
      	movl %ecx, (JB_PC*4)(%eax)
 
+	LEAVE /* pop frame pointer to prepare for tail-call.  */
 	/* Make a tail call to __sigjmp_save; it takes the same args.  */
 #ifdef	PIC
 	/* We cannot use the PLT, because it requires that %ebx be set, but
@@ -52,9 +61,9 @@ ENTRY (__sigsetjmp)
 L(here):
 	popl %ecx
 	addl $_GLOBAL_OFFSET_TABLE_+[.-L(here)], %ecx
-	movl C_SYMBOL_NAME(__sigjmp_save@GOT)(%ecx), %ecx
+	movl C_SYMBOL_NAME (BP_SYM (__sigjmp_save)@GOT)(%ecx), %ecx
 	jmp *%ecx
 #else
-	jmp __sigjmp_save
+	jmp BP_SYM (__sigjmp_save)
 #endif
-END (__sigsetjmp)
+END (BP_SYM (__sigsetjmp))
Index: sysdeps/i386/bits/setjmp.h
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/bits/setjmp.h,v
retrieving revision 1.4
diff -u -p -r1.4 setjmp.h
--- setjmp.h	1998/04/22 09:27:22	1.4
+++ setjmp.h	2000/06/29 22:38:49
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997, 1998 Free Software Foundation, Inc.
+/* Copyright (C) 1997, 1998, 2000 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
@@ -29,9 +29,31 @@
 # define JB_BP	3
 # define JB_SP	4
 # define JB_PC	5
+# define JB_SIZE 24
 #endif
 
-#ifndef	_ASM
+#ifdef	_ASM
+/* We internally convert all setjmp (buf) calls to sigsetjmp (buf, mask),
+   so we must shift with the call frame to insert the mask argument.  */
+# if __BOUNDED_POINTERS__
+#  define PUSH_SIGNAL_MASK(MASK)				\
+	popl %eax;		/* return address */		\
+	popl %ecx;		/* jmp_buf value */		\
+	popl %edx;		/* jmp_buf low bound */		\
+	pushl 0(%esp);		/* jmp_buf high bound */	\
+	movel $MASK, 4(%esp);					\
+	pushl %edx;						\
+	pushl %ecx;						\
+	pushl %eax
+# else
+#  define PUSH_SIGNAL_MASK(MASK)			\
+	popl %eax;		/* return address */	\
+	popl %ecx;		/* jmp_buf */		\
+	pushl $MASK;					\
+	pushl %ecx;					\
+	pushl %eax
+# endif
+#else
 typedef int __jmp_buf[6];
 #endif
 
Index: sysdeps/i386/elf/setjmp.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/elf/setjmp.S,v
retrieving revision 1.4
diff -u -p -r1.4 setjmp.S
--- setjmp.S	2000/06/09 06:14:39	1.4
+++ setjmp.S	2000/06/29 22:38:49
@@ -21,50 +21,49 @@
 #define _ASM
 #define _SETJMP_H
 #include <bits/setjmp.h>
+#include "bp-sym.h"
 #include "bp-asm.h"
 
-#define PARMS	LINKAGE		/* no space for saved regs */
-#define JBUF	PARMS
-#define SGMSK	JBUF+PRT_SIZE
-
 	/* We include the BSD entry points here as well but we make
 	   them weak.  */
-ENTRY (setjmp)
-	.weak C_SYMBOL_NAME (setjmp)
-	popl %eax		/* Pop return PC.  */
-	popl %ecx		/* Pop jmp_buf argument.  */
-	pushl $1		/* Push second argument of zero.  */
-	pushl %ecx		/* Push back first argument.  */
-	pushl %eax		/* Push back return PC.  */
+ENTRY (BP_SYM (setjmp))
+	.weak C_SYMBOL_NAME (BP_SYM (setjmp))
+	PUSH_SIGNAL_MASK (1)
 	/* Note that we have to use a non-exported symbol in the next
 	   jump since otherwise gas will emit it as a jump through the
 	   PLT which is what we cannot use here.  */
 	jmp .Linternal_sigsetjmp
-END (setjmp)
+END (BP_SYM (setjmp))
 
 	/* Binary compatibility entry point.  */
-ENTRY (_setjmp)
-	.weak C_SYMBOL_NAME (_setjmp)
-ENTRY (__setjmp)
-	popl %eax		/* Pop return address.  */
-	popl %ecx		/* Pop jmp_buf.  */
-	pushl $0		/* Push zero argument.  */
-	pushl %ecx		/* Push jmp_buf.  */
-	pushl %eax		/* Push back return address.  */
-
-ENTRY (__sigsetjmp)
-.Linternal_sigsetjmp = __sigsetjmp
-	movl 4(%esp), %eax	/* User's jmp_buf in %eax.  */
+ENTRY (BP_SYM (_setjmp))
+	.weak C_SYMBOL_NAME (BP_SYM (_setjmp))
+ENTRY (BP_SYM (__setjmp))
+	PUSH_SIGNAL_MASK (0)
+	/* FALL THROUGH */
+
+#define PARMS	LINKAGE		/* no space for saved regs */
+#define JMPBUF	PARMS
+#define SIGMSK	JMPBUF+PTR_SIZE
+
+ENTRY (BP_SYM (__sigsetjmp))
+.Linternal_sigsetjmp = BP_SYM (__sigsetjmp)
+	ENTER
+
+	movl JMPBUF(%esp), %eax
+	CHECK_BOUNDS_BOTH_WIDE (%eax, JMPBUF(%esp), $JB_SIZE)
+
      	/* Save registers.  */
 	movl %ebx, (JB_BX*4)(%eax)
 	movl %esi, (JB_SI*4)(%eax)
 	movl %edi, (JB_DI*4)(%eax)
 	movl %ebp, (JB_BP*4)(%eax)
-	leal JBUF(%esp), %ecx	/* Save SP as it will be after we return.  */
+	leal JMPBUF(%esp), %ecx	/* Save SP as it will be after we return.  */
      	movl %ecx, (JB_SP*4)(%eax)
-	movl 0(%esp), %ecx	/* Save PC we are returning to now.  */
+	movl PCOFF(%esp), %ecx	/* Save PC we are returning to now.  */
      	movl %ecx, (JB_PC*4)(%eax)
 
+	LEAVE /* pop frame pointer to prepare for tail-call.  */
 	/* Make a tail call to __sigjmp_save; it takes the same args.  */
 #ifdef	PIC
 	/* We cannot use the PLT, because it requires that %ebx be set, but
@@ -74,9 +73,9 @@ ENTRY (__sigsetjmp)
 	call here
 here:	popl %ecx
 	addl $_GLOBAL_OFFSET_TABLE_+[.-here], %ecx
-	movl C_SYMBOL_NAME(__sigjmp_save@GOT)(%ecx), %ecx
+	movl C_SYMBOL_NAME (BP_SYM (__sigjmp_save)@GOT)(%ecx), %ecx
 	jmp *%ecx
 #else
-	jmp __sigjmp_save
+	jmp BP_SYM (__sigjmp_save)
 #endif
-END (__sigsetjmp)
+END (BP_SYM (__sigsetjmp))

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