From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001
From: André Fabian Silva Delgado <emulatorman@parabola.nu>
Date: Wed, 5 Aug 2015 17:04:01 -0300
Subject: Initial import

---
 arch/m32r/lib/strlen.S | 117 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 117 insertions(+)
 create mode 100644 arch/m32r/lib/strlen.S

(limited to 'arch/m32r/lib/strlen.S')

diff --git a/arch/m32r/lib/strlen.S b/arch/m32r/lib/strlen.S
new file mode 100644
index 000000000..916de9e8f
--- /dev/null
+++ b/arch/m32r/lib/strlen.S
@@ -0,0 +1,117 @@
+/*
+ *  linux/arch/m32r/strlen.S --  strlen code.
+ *
+ *  Copyright (C) 2001  Hirokazu Takata
+ *
+ *  size_t strlen(const char *s);
+ *
+ */
+
+#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
-- 
cgit v1.2.3-54-g00ecf