[dev.cc] runtime: convert basic library routines from C to Go

float.c held bit patterns for special float64 values,
hiding from the real uses. Rewrite Go code not to
refer to those values directly.

Convert library routines in runtime.c and string.c.

LGTM=r
R=r, dave
CC=austin, dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/170330043

1 files changed, 0 insertions, 226 deletions

diff --git a/src/runtime/string.c b/src/runtime/string.c
deleted file mode 100644
index ed5debc33e..0000000000
--- a/src/runtime/string.c
+++ /dev/null
@@ -1,226 +0,0 @@
-// Copyright 2009 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 "runtime.h"
-#include "arch_GOARCH.h"
-#include "malloc.h"
-#include "race.h"
-#include "textflag.h"
-
-String	runtime·emptystring;
-
-#pragma textflag NOSPLIT
-intgo
-runtime·findnull(byte *s)
-{
-	intgo l;
-
-	if(s == nil)
-		return 0;
-	for(l=0; s[l]!=0; l++)
-		;
-	return l;
-}
-
-intgo
-runtime·findnullw(uint16 *s)
-{
-	intgo l;
-
-	if(s == nil)
-		return 0;
-	for(l=0; s[l]!=0; l++)
-		;
-	return l;
-}
-
-uintptr runtime·maxstring = 256; // a hint for print
-
-#pragma textflag NOSPLIT
-String
-runtime·gostringnocopy(byte *str)
-{
-	String s;
-	uintptr ms;
-	
-	s.str = str;
-	s.len = runtime·findnull(str);
-	while(true) {
-		ms = runtime·maxstring;
-		if(s.len <= ms || runtime·casp((void**)&runtime·maxstring, (void*)ms, (void*)s.len))
-			return s;
-	}
-}
-
-// TODO: move this elsewhere
-enum
-{
-	Bit1	= 7,
-	Bitx	= 6,
-	Bit2	= 5,
-	Bit3	= 4,
-	Bit4	= 3,
-	Bit5	= 2,
-
-	Tx	= ((1<<(Bitx+1))-1) ^ 0xFF,	/* 1000 0000 */
-	T2	= ((1<<(Bit2+1))-1) ^ 0xFF,	/* 1100 0000 */
-	T3	= ((1<<(Bit3+1))-1) ^ 0xFF,	/* 1110 0000 */
-	T4	= ((1<<(Bit4+1))-1) ^ 0xFF,	/* 1111 0000 */
-
-	Rune1	= (1<<(Bit1+0*Bitx))-1,		/* 0000 0000 0111 1111 */
-	Rune2	= (1<<(Bit2+1*Bitx))-1,		/* 0000 0111 1111 1111 */
-	Rune3	= (1<<(Bit3+2*Bitx))-1,		/* 1111 1111 1111 1111 */
-
-	Maskx	= (1<<Bitx)-1,			/* 0011 1111 */
-
-	Runeerror	= 0xFFFD,
-
-	SurrogateMin = 0xD800,
-	SurrogateMax = 0xDFFF,
-
-	Runemax	= 0x10FFFF,	/* maximum rune value */
-};
-
-static int32
-runetochar(byte *str, int32 rune)  /* note: in original, arg2 was pointer */
-{
-	/* Runes are signed, so convert to unsigned for range check. */
-	uint32 c;
-
-	/*
-	 * one character sequence
-	 *	00000-0007F => 00-7F
-	 */
-	c = rune;
-	if(c <= Rune1) {
-		str[0] = c;
-		return 1;
-	}
-
-	/*
-	 * two character sequence
-	 *	0080-07FF => T2 Tx
-	 */
-	if(c <= Rune2) {
-		str[0] = T2 | (c >> 1*Bitx);
-		str[1] = Tx | (c & Maskx);
-		return 2;
-	}
-
-	/*
-	 * If the Rune is out of range or a surrogate half, convert it to the error rune.
-	 * Do this test here because the error rune encodes to three bytes.
-	 * Doing it earlier would duplicate work, since an out of range
-	 * Rune wouldn't have fit in one or two bytes.
-	 */
-	if (c > Runemax)
-		c = Runeerror;
-	if (SurrogateMin <= c && c <= SurrogateMax)
-		c = Runeerror;
-
-	/*
-	 * three character sequence
-	 *	0800-FFFF => T3 Tx Tx
-	 */
-	if (c <= Rune3) {
-		str[0] = T3 |  (c >> 2*Bitx);
-		str[1] = Tx | ((c >> 1*Bitx) & Maskx);
-		str[2] = Tx |  (c & Maskx);
-		return 3;
-	}
-
-	/*
-	 * four character sequence (21-bit value)
-	 *     10000-1FFFFF => T4 Tx Tx Tx
-	 */
-	str[0] = T4 | (c >> 3*Bitx);
-	str[1] = Tx | ((c >> 2*Bitx) & Maskx);
-	str[2] = Tx | ((c >> 1*Bitx) & Maskx);
-	str[3] = Tx | (c & Maskx);
-	return 4;
-}
-
-String runtime·gostringsize(intgo);
-
-String
-runtime·gostringw(uint16 *str)
-{
-	intgo n1, n2, i;
-	byte buf[8];
-	String s;
-
-	n1 = 0;
-	for(i=0; str[i]; i++)
-		n1 += runetochar(buf, str[i]);
-	s = runtime·gostringsize(n1+4);
-	n2 = 0;
-	for(i=0; str[i]; i++) {
-		// check for race
-		if(n2 >= n1)
-			break;
-		n2 += runetochar(s.str+n2, str[i]);
-	}
-	s.len = n2;
-	s.str[s.len] = 0;
-	return s;
-}
-
-int32
-runtime·strcmp(byte *s1, byte *s2)
-{
-	uintptr i;
-	byte c1, c2;
-
-	for(i=0;; i++) {
-		c1 = s1[i];
-		c2 = s2[i];
-		if(c1 < c2)
-			return -1;
-		if(c1 > c2)
-			return +1;
-		if(c1 == 0)
-			return 0;
-	}
-}
-
-int32
-runtime·strncmp(byte *s1, byte *s2, uintptr n)
-{
-	uintptr i;
-	byte c1, c2;
-
-	for(i=0; i<n; i++) {
-		c1 = s1[i];
-		c2 = s2[i];
-		if(c1 < c2)
-			return -1;
-		if(c1 > c2)
-			return +1;
-		if(c1 == 0)
-			break;
-	}
-	return 0;
-}
-
-byte*
-runtime·strstr(byte *s1, byte *s2)
-{
-	byte *sp1, *sp2;
-
-	if(*s2 == 0)
-		return s1;
-	for(; *s1; s1++) {
-		if(*s1 != *s2)
-			continue;
-		sp1 = s1;
-		sp2 = s2;
-		for(;;) {
-			if(*sp2 == 0)
-				return s1;
-			if(*sp1++ != *sp2++)
-				break;
-		}
-	}
-	return nil;
-}