This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / arch / m32r / lib / strlen.S

diff --git a/arch/m32r/lib/strlen.S b/arch/m32r/lib/strlen.S
new file mode 100644 (file)
index 0000000..8d23cfb
--- /dev/null
+++ b/arch/m32r/lib/strlen.S
@@ -0,0 +1,120 @@
+/*
+ *  linux/arch/m32r/strlen.S --  strlen code.
+ *
+ *  Copyright (C) 2001  Hirokazu Takata
+ *
+ *  size_t strlen(const char *s);
+ *
+ */
+/* $Id$ */
+
+
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+#ifdef CONFIG_ISA_DUAL_ISSUE
+
+       .text
+ENTRY(strlen)
+       mv      r6, r0              ||  ldi     r2, #0
+       and3    r0, r0, #3
+       bnez    r0, strlen_byte
+;
+strlen_word:
+       ld      r0, @r6+
+;
+       seth    r5, #high(0x01010101)
+       or3     r5, r5, #low(0x01010101)
+       sll3    r7, r5, #7
+strlen_word_loop:
+       ld      r1, @r6+            ||  not     r4, r0
+       sub     r0, r5              ||  and     r4, r7
+       and     r4, r0
+       bnez    r4, strlen_last_bytes
+       ld      r0, @r6+            ||  not     r4, r1
+       sub     r1, r5              ||  and     r4, r7
+       and     r4, r1              ||  addi    r2, #4
+       bnez    r4, strlen_last_bytes
+       addi    r2, #4              ||  bra.s   strlen_word_loop
+
+       ; NOTE: If a null char. exists, return 0.
+       ; if ((x - 0x01010101) & ~x & 0x80808080)
+       ;     return 0;
+;
+strlen_byte:
+       ldb     r1, @r6             ||  addi    r6, #1
+       beqz    r1, strlen_exit
+       addi    r2, #1              ||  bra.s   strlen_byte
+;
+strlen_last_bytes:
+       ldi     r0, #4              ||  addi    r6, #-8
+;
+strlen_byte_loop:
+       ldb     r1, @r6             ||  addi    r6, #1
+       addi    r0, #-1             ||  cmpz    r1
+       bc.s    strlen_exit         ||  cmpz    r0
+       addi    r2, #1              ||  bnc.s   strlen_byte_loop
+;
+strlen_exit:
+       mv      r0, r2              ||  jmp     r14
+
+#else /* not CONFIG_ISA_DUAL_ISSUE */
+
+       .text
+ENTRY(strlen)
+       mv      r6, r0
+       ldi     r2, #0
+       and3    r0, r0, #3
+       bnez    r0, strlen_byte
+;
+strlen_word:
+       ld      r0, @r6+
+;
+       seth    r5, #high(0x01010101)
+       or3     r5, r5, #low(0x01010101)
+       sll3    r7, r5, #7
+strlen_word_loop:
+       ld      r1, @r6+
+       not     r4, r0          ; NOTE: If a null char. exists, return 0.
+       sub     r0, r5          ; if ((x - 0x01010101) & ~x & 0x80808080)
+       and     r4, r7          ;     return 0;
+       and     r4, r0
+       bnez    r4, strlen_last_bytes
+       addi    r2, #4
+;
+       ld      r0, @r6+
+       not     r4, r1          ; NOTE: If a null char. exists, return 0.
+       sub     r1, r5          ; if ((x - 0x01010101) & ~x & 0x80808080)
+       and     r4, r7          ;     return 0;
+       and     r4, r1
+       bnez    r4, strlen_last_bytes
+       addi    r2, #4
+       bra     strlen_word_loop
+;
+strlen_byte:
+       ldb     r1, @r6
+       addi    r6, #1
+       beqz    r1, strlen_exit
+       addi    r2, #1
+       bra     strlen_byte
+;
+strlen_last_bytes:
+       ldi     r0, #4
+       addi    r6, #-8
+;
+strlen_byte_loop:
+       ldb     r1, @r6
+       addi    r6, #1
+       addi    r0, #-1
+       beqz    r1, strlen_exit
+       addi    r2, #1
+       bnez    r0, strlen_byte_loop
+;
+strlen_exit:
+       mv      r0, r2
+       jmp     r14
+
+#endif /* not CONFIG_ISA_DUAL_ISSUE */
+
+       .end