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+/* strtok (str, delim) -- Return next DELIM separated token from STR.
+ For AMD x86-64.
+ Copyright (C) 1998, 2000, 2001, 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Based on i686 version contributed by Ulrich Drepper
+ <drepper@cygnus.com>, 1998.
+
+ 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdep.h>
+#include "asm-syntax.h"
+#include "bp-sym.h"
+#include "bp-asm.h"
+
+/* This file can be used for the strtok and strtok_r functions:
+
+ strtok:
+ INPUT PARAMETER:
+ str %rdi
+ delim %rsi
+
+ strtok_r:
+ INPUT PARAMETER:
+ str %rdi
+ delim %rsi
+ save_ptr %rdx
+
+ We do a common implementation here. */
+
+#ifdef USE_AS_STRTOK_R
+# define SAVE_PTR (%r9)
+#else
+ .bss
+ .local save_ptr
+ ASM_TYPE_DIRECTIVE (save_ptr, @object)
+ .size save_ptr, 8
+save_ptr:
+ .space 8
+
+# ifdef PIC
+# define SAVE_PTR save_ptr(%rip)
+# else
+# define SAVE_PTR save_ptr
+# endif
+
+# define FUNCTION strtok
+#endif
+
+ .text
+ENTRY (BP_SYM (FUNCTION))
+ /* 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.
+ Before inserting marks for the stop characters we clear the whole
+ table. */
+ movq %rdi, %r8 /* Save value. */
+ subq $256, %rsp /* Make space for 256 bytes. */
+ movq $32, %rcx /* 32*8 bytes = 256 bytes. */
+ movq %rsp, %rdi
+ xorq %rax, %rax /* We store 0s. */
+ cld
+ rep
+ stosq
+
+ /* Note: %rcx = 0 !!! */
+
+#ifdef USE_AS_STRTOK_R
+ /* The value is stored in the third argument. */
+ movq %rdx, %rax
+ movq %rdx, %r9 /* Save value - see def. of SAVE_PTR. */
+ movq (%rax), %rax
+#else
+ /* The value is in the local variable defined above. But
+ we have to take care for PIC code. */
+ movq SAVE_PTR, %rax
+#endif
+ movq %r8, %rdx /* Get start of string. */
+
+ /* If the pointer is NULL we have to use the stored value of
+ the last run. */
+ cmpq $0, %rdx
+ cmove %rax, %rdx
+ testq %rdx, %rdx
+ jz L(returnNULL)
+ movq %rsi, %rax /* Get start of delimiter set. */
+
+/* For understanding the following code remember that %rcx == 0 now.
+ Although all the following instruction only modify %cl we always
+ have a correct zero-extended 64-bit value in %rcx. */
+
+L(2): movb (%rax), %cl /* get byte from stopset */
+ testb %cl, %cl /* is NUL char? */
+ jz L(1) /* yes => start compare loop */
+ movb %cl, (%rsp,%rcx) /* set corresponding byte in stopset table */
+
+ movb 1(%rax), %cl /* get byte from stopset */
+ testb $0xff, %cl /* is NUL char? */
+ jz L(1) /* yes => start compare loop */
+ movb %cl, (%rsp,%rcx) /* set corresponding byte in stopset table */
+
+ movb 2(%rax), %cl /* get byte from stopset */
+ testb $0xff, %cl /* is NUL char? */
+ jz L(1) /* yes => start compare loop */
+ movb %cl, (%rsp,%rcx) /* set corresponding byte in stopset table */
+
+ movb 3(%rax), %cl /* get byte from stopset */
+ addq $4, %rax /* increment stopset pointer */
+ movb %cl, (%rsp,%rcx) /* set corresponding byte in stopset table */
+ testb $0xff, %cl /* is NUL char? */
+ jnz L(2) /* no => process next dword from stopset */
+
+L(1):
+
+ leaq -4(%rdx), %rax /* prepare loop */
+
+ /* We use a neat trick for the following loop. Normally we would
+ have to test for two termination conditions
+ 1. a character in the stopset was found
+ and
+ 2. the end of the string was found
+ As a sign that the character is in the stopset we store its
+ value in the table. The value of NUL is NUL so the loop
+ terminates for NUL in every case. */
+
+L(3): addq $4, %rax /* adjust pointer for full loop round */
+
+ movb (%rax), %cl /* get byte from string */
+ testb %cl, (%rsp,%rcx) /* is it contained in stopset? */
+ jz L(4) /* no => start of token */
+
+ movb 1(%rax), %cl /* get byte from string */
+ testb %cl, (%rsp,%rcx) /* is it contained in stopset? */
+ jz L(5) /* no => start of token */
+
+ movb 2(%rax), %cl /* get byte from string */
+ testb %cl, (%rsp,%rcx) /* is it contained in stopset? */
+ jz L(6) /* no => start of token */
+
+ movb 3(%rax), %cl /* get byte from string */
+ testb %cl, (%rsp,%rcx) /* is it contained in stopset? */
+ jnz L(3) /* yes => start of loop */
+
+ incq %rax /* adjust pointer */
+L(6): incq %rax
+L(5): incq %rax
+
+ /* Now we have to terminate the string. */
+
+L(4): leaq -4(%rax), %rdx /* We use %rDX for the next run. */
+
+L(7): addq $4, %rdx /* adjust pointer for full loop round */
+
+ movb (%rdx), %cl /* get byte from string */
+ cmpb %cl, (%rsp,%rcx) /* is it contained in skipset? */
+ je L(8) /* yes => return */
+
+ movb 1(%rdx), %cl /* get byte from string */
+ cmpb %cl, (%rsp,%rcx) /* is it contained in skipset? */
+ je L(9) /* yes => return */
+
+ movb 2(%rdx), %cl /* get byte from string */
+ cmpb %cl, (%rsp,%rcx) /* is it contained in skipset? */
+ je L(10) /* yes => return */
+
+ movb 3(%rdx), %cl /* get byte from string */
+ cmpb %cl, (%rsp,%rcx) /* is it contained in skipset? */
+ jne L(7) /* no => start loop again */
+
+ incq %rdx /* adjust pointer */
+L(10): incq %rdx
+L(9): incq %rdx
+
+L(8): cmpq %rax, %rdx
+ je L(returnNULL) /* There was no token anymore. */
+
+ movb $0, (%rdx) /* Terminate string. */
+
+ /* Are we at end of string? */
+ cmpb $0, %cl
+ leaq 1(%rdx), %rcx
+ cmovne %rcx, %rdx
+
+ /* Store the pointer to the next character. */
+ movq %rdx, SAVE_PTR
+
+L(epilogue):
+ /* Remove the stopset table. */
+ addq $256, %rsp
+ retq
+
+L(returnNULL):
+ xorq %rax, %rax
+ jmp L(epilogue)
+
+END (BP_SYM (FUNCTION))