30 lines
778 B
C
30 lines
778 B
C
|
/* indexbyte.c -- implement strings.IndexByte for Go.
|
||
|
|
|
||
|
|
Copyright 2013 The Go Authors. All rights reserved.
|
||
|
|
Use of this source code is governed by a BSD-style
|
||
|
|
license that can be found in the LICENSE file. */
|
||
|
|
|
||
|
|
#include <stddef.h>
|
||
|
|
|
||
|
|
#include "runtime.h"
|
||
|
|
#include "go-string.h"
|
||
|
|
|
||
|
|
/* This is in C so that the compiler can optimize it appropriately.
|
||
|
|
We deliberately don't split the stack in case it does call the
|
||
|
|
library function, which shouldn't need much stack space. */
|
||
|
|
|
||
|
|
intgo IndexByte (String, char)
|
||
|
|
__asm__ (GOSYM_PREFIX "strings.IndexByte")
|
||
|
|
__attribute__ ((no_split_stack));
|
||
|
|
|
||
|
|
intgo
|
||
|
|
IndexByte (String s, char b)
|
||
|
|
{
|
||
|
|
const char *p;
|
||
|
|
|
||
|
|
p = __builtin_memchr ((const char *) s.str, b, s.len);
|
||
|
|
if (p == NULL)
|
||
|
|
return -1;
|
||
|
|
return p - (const char *) s.str;
|
||
|
|
}
|