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[ This is a retransmission -- I thought I had sent it out,
but it didn't show up on the list. ]
i[36]86: No build regressions.
No runtime regressions for non-BP.
Now passes runtime tests for BP.
This has a new optimization: don't write back to SAVE_PTR when
returning NULL.
OK?
2000-07-26 Greg McGary <greg@mcgary.org>
* sysdeps/i386/strtok.S: Fix bounds checks to pass tests.
(SAVE_PTR): New macro. (save_ptr): Expand size as BP.
(strtok): Don't bother to write into SAVE_PTR when returning NULL.
* sysdeps/i386/i686/strtok.S: Likewise.
* sysdeps/i386/bp-asm.h (RETURN_BOUNDED_POINTER,
RETURN_NULL_BOUNDED_POINTER): Use %ecx as the scratch register.
Index: sysdeps/i386/strtok.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/strtok.S,v
retrieving revision 1.9
diff -u -p -B -w -r1.9 strtok.S
--- strtok.S 2000/06/26 22:14:59 1.9
+++ strtok.S 2000/07/26 08:19:39
@@ -39,14 +39,26 @@
We do a common implementation here. */
-#ifndef USE_AS_STRTOK_R
+#ifdef USE_AS_STRTOK_R
+# define SAVE_PTR 0(%ecx)
+#else
.bss
.local save_ptr
ASM_TYPE_DIRECTIVE (save_ptr, @object)
.size save_ptr, 4
save_ptr:
+# if __BOUNDED_POINTERS__
+ .space 12
+# else
.space 4
+# endif
+# ifdef PIC
+# define SAVE_PTR save_ptr@GOTOFF(%ebx)
+# else
+# define SAVE_PTR save_ptr
+# endif
+
#define FUNCTION strtok
#endif
@@ -62,10 +74,9 @@ ENTRY (BP_SYM (FUNCTION))
movl STR(%esp), %edx
movl DELIM(%esp), %eax
- CHECK_BOUNDS_LOW (%edx, STR(%esp))
CHECK_BOUNDS_LOW (%eax, DELIM(%esp))
-#if !defined (USE_AS_STRTOK_R) && defined (PIC)
+#if !defined USE_AS_STRTOK_R && defined PIC
pushl %ebx /* Save PIC register. */
call L(here)
L(here):
@@ -76,7 +87,22 @@ L(here):
/* If the pointer is NULL we have to use the stored value of
the last run. */
cmpl $0, %edx
- jne L(0)
+#if __BOUNDED_POINTERS__
+ movl SAVE(%esp), %ecx
+ je L(0)
+ /* Save bounds of incoming non-NULL STR into save area. */
+ movl 4+STR(%esp), %eax
+ movl %eax, 4+SAVE_PTR
+ movl 8+STR(%esp), %eax
+ movl %eax, 8+SAVE_PTR
+ CHECK_BOUNDS_LOW (%edx, SAVE_PTR)
+ jmp L(1)
+L(0): movl SAVE_PTR, %edx
+ CHECK_BOUNDS_LOW (%edx, SAVE_PTR)
+ jmp L(1)
+#else
+ jne L(1)
+#endif
#ifdef USE_AS_STRTOK_R
/* The value is stored in the third argument. */
@@ -85,14 +111,10 @@ L(here):
#else
/* The value is in the local variable defined above. But
we have to take care for PIC code. */
-# ifndef PIC
- movl save_ptr, %edx
-# else
- movl save_ptr@GOTOFF(%ebx), %edx
-# endif
+ movl SAVE_PTR, %edx
#endif
-L(0):
+L(1):
/* First we create a table with flags for all possible characters.
For the ASCII (7bit/8bit) or ISO-8859-X character sets which are
supported by the C string functions we have 256 characters.
@@ -195,7 +217,7 @@ L(2): movb (%eax), %cl /* get byte from
L(1_3): incl %eax /* adjust pointer for bounds check */
L(1_2): incl %eax /* ditto */
L(1_1): incl %eax /* ditto */
-L(1_0): CHECK_BOUNDS_HIGH (%eax, DELIM(%esp), jb)
+L(1_0): CHECK_BOUNDS_HIGH (%eax, DELIM(%esp), jbe)
#else
L(1_3):; L(1_2):; L(1_1): /* fall through */
#endif
@@ -273,25 +295,17 @@ L(8): /* Remove the stopset table. */
incl %edx
L(11):
-L(return):
/* Store the pointer to the next character. */
#ifdef USE_AS_STRTOK_R
movl SAVE(%esp), %ecx
- movl %edx, (%ecx)
-#else
-# ifndef PIC
- movl %edx, save_ptr
-# else
- movl %edx, save_ptr@GOTOFF(%ebx)
- popl %ebx
-# endif
#endif
-#if __BOUNDED_POINTERS__
- testl %eax, %eax
- jz L(ret)
- CHECK_BOUNDS_HIGH (%eax, STR(%esp), jb)
- RETURN_BOUNDED_POINTER (STR(%esp))
-L(ret):
+ movl %edx, SAVE_PTR
+ CHECK_BOUNDS_HIGH (%edx, SAVE_PTR, jb)
+ RETURN_BOUNDED_POINTER (SAVE_PTR)
+
+L(epilogue):
+#if !defined USE_AS_STRTOK_R && defined PIC
+ popl %ebx
#endif
LEAVE
RET_PTR
@@ -299,6 +313,6 @@ L(ret):
L(returnNULL):
xorl %eax, %eax
RETURN_NULL_BOUNDED_POINTER
- jmp L(return)
+ jmp L(epilogue)
END (BP_SYM (FUNCTION))
Index: sysdeps/i386/i686/strtok.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/i386/i686/strtok.S,v
retrieving revision 1.4
diff -u -p -B -w -r1.4 strtok.S
--- strtok.S 2000/06/26 22:15:00 1.4
+++ strtok.S 2000/07/26 08:19:39
@@ -39,30 +39,48 @@
We do a common implementation here. */
-#ifndef USE_AS_STRTOK_R
+#ifdef USE_AS_STRTOK_R
+# define SAVE_PTR 0(%ecx)
+#else
.bss
.local save_ptr
ASM_TYPE_DIRECTIVE (save_ptr, @object)
.size save_ptr, 4
save_ptr:
+# if __BOUNDED_POINTERS__
+ .space 12
+# else
.space 4
+# endif
-#define FUNCTION BP_SYM (strtok)
+# ifdef PIC
+# define SAVE_PTR save_ptr@GOTOFF(%ebx)
+# else
+# define SAVE_PTR save_ptr
#endif
- .text
+# define FUNCTION strtok
+#endif
#if !defined USE_AS_STRTOK_R && defined PIC
-0: movl (%esp), %ebx
- ret
+# define PARMS LINKAGE+256+4 /* space for table and saved PIC register */
+#else
+# define PARMS LINKAGE+256 /* space for table */
#endif
-
-#define PARMS LINKAGE /* no space for saved regs */
#define RTN PARMS
#define STR RTN+RTN_SIZE
#define DELIM STR+PTR_SIZE
+#ifdef USE_AS_STRTOK_R
#define SAVE DELIM+PTR_SIZE
+#endif
+
+ .text
+#if !defined USE_AS_STRTOK_R && defined PIC
+0: movl (%esp), %ebx
+ ret
+#endif
+
ENTRY (BP_SYM (FUNCTION))
ENTER
@@ -89,36 +107,39 @@ ENTRY (BP_SYM (FUNCTION))
/* Note: %ecx = 0 !!! */
movl %edx, %edi
-#if !defined USE_AS_STRTOK_R && defined PIC
- movl 264(%esp), %edx /* Get start of string. */
-#else
- movl 260(%esp), %edx /* Get start of string. */
-#endif
+ movl STR(%esp), %edx /* Get start of string. */
#ifdef USE_AS_STRTOK_R
/* The value is stored in the third argument. */
- movl 268(%esp), %eax
+ movl SAVE(%esp), %eax
movl (%eax), %eax
#else
/* The value is in the local variable defined above. But
we have to take care for PIC code. */
-# ifndef PIC
- movl save_ptr, %eax
-# else
- movl save_ptr@GOTOFF(%ebx), %eax
-# endif
+ movl SAVE_PTR, %eax
#endif
/* If the pointer is NULL we have to use the stored value of
the last run. */
cmpl $0, %edx
cmove %eax, %edx
-
-#if !defined USE_AS_STRTOK_R && defined PIC
- movl 268(%esp), %eax /* Get start of delimiter set. */
-#else
- movl 264(%esp), %eax /* Get start of delimiter set. */
+#if __BOUNDED_POINTERS__
+# ifdef USE_AS_STRTOK_R
+ movl SAVE(%esp), %ecx /* borrow %ecx for a moment */
#endif
+ je L(0)
+ /* Save bounds of incoming non-NULL STR into save area. */
+ movl 4+STR(%esp), %eax
+ movl %eax, 4+SAVE_PTR
+ movl 8+STR(%esp), %eax
+ movl %eax, 8+SAVE_PTR
+L(0): CHECK_BOUNDS_LOW (%edx, SAVE_PTR)
+# ifdef USE_AS_STRTOK_R
+ xorl %ecx, %ecx /* restore %ecx to zero */
+# endif
+#endif
+ movl DELIM(%esp), %eax /* Get start of delimiter set. */
+ CHECK_BOUNDS_LOW (%eax, DELIM(%esp))
/* For understanding the following code remember that %ecx == 0 now.
Although all the following instruction only modify %cl we always
@@ -126,17 +147,17 @@ ENTRY (BP_SYM (FUNCTION))
L(2): movb (%eax), %cl /* get byte from stopset */
testb %cl, %cl /* is NUL char? */
- jz L(1) /* yes => start compare loop */
+ jz L(1_1) /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 1(%eax), %cl /* get byte from stopset */
testb $0xff, %cl /* is NUL char? */
- jz L(1) /* yes => start compare loop */
+ jz L(1_2) /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 2(%eax), %cl /* get byte from stopset */
testb $0xff, %cl /* is NUL char? */
- jz L(1) /* yes => start compare loop */
+ jz L(1_3) /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 3(%eax), %cl /* get byte from stopset */
@@ -145,7 +166,16 @@ L(2): movb (%eax), %cl /* get byte from
testb $0xff, %cl /* is NUL char? */
jnz L(2) /* no => process next dword from stopset */
-L(1): leal -4(%edx), %eax /* prepare loop */
+#if __BOUNDED_POINTERS__
+ jmp L(1_0) /* pointer is correct for bounds check */
+L(1_3): incl %eax /* adjust pointer for bounds check */
+L(1_2): incl %eax /* ditto */
+L(1_1): incl %eax /* ditto */
+L(1_0): CHECK_BOUNDS_HIGH (%eax, DELIM(%esp), jbe)
+#else
+L(1_3):; L(1_2):; L(1_1): /* fall through */
+#endif
+ leal -4(%edx), %eax /* prepare loop */
/* We use a neat trick for the following loop. Normally we would
have to test for two termination conditions
@@ -204,10 +234,7 @@ L(7): addl $4, %edx /* adjust pointer f
L(10): incl %edx
L(9): incl %edx
-L(8): /* Remove the stopset table. */
- addl $256, %esp
-
- cmpl %eax, %edx
+L(8): cmpl %eax, %edx
je L(returnNULL) /* There was no token anymore. */
movb $0, (%edx) /* Terminate string. */
@@ -217,22 +244,26 @@ L(8): /* Remove the stopset table. */
leal 1(%edx), %ecx
cmovne %ecx, %edx
-L(return):
/* Store the pointer to the next character. */
#ifdef USE_AS_STRTOK_R
- movl 12(%esp), %ecx
- movl %edx, (%ecx)
-#else
-# ifndef PIC
- movl %edx, save_ptr
-# else
- movl %edx, save_ptr@GOTOFF(%ebx)
- popl %ebx
+ movl SAVE(%esp), %ecx
# endif
+ movl %edx, SAVE_PTR
+ CHECK_BOUNDS_HIGH (%edx, SAVE_PTR, jb)
+ RETURN_BOUNDED_POINTER (SAVE_PTR)
+
+L(epilogue):
+ /* Remove the stopset table. */
+ addl $256, %esp
+#if !defined USE_AS_STRTOK_R && defined PIC
+ popl %ebx
#endif
- ret
+ LEAVE
+ RET_PTR
L(returnNULL):
xorl %eax, %eax
- jmp L(return)
+ RETURN_NULL_BOUNDED_POINTER
+ jmp L(epilogue)
+
END (BP_SYM (FUNCTION))
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