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7d2f33dc1

Denys Vlasenko

2017-07-27

SUCCESS Duration: 143s

Subject

ed: code shrink

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

editors/ed.c +43 -51

editors/ed.c+43 -51

@@ -78,13 +78,6 @@ static int bad_nums(int num1, int num2, const char *for_what)
	return 0;
	}

-	static char skip_blank(const char cp)
-	{
-	while (isblank(*cp))
-	cp++;
-	return (char *)cp;
-	}
-
	/*
	* Return a pointer to the specified line number.
	*/
@@ -138,15 +131,13 @@ static int findString(const LINE lp, const char str, int len, int offset)
	const char cp, ncp;

	cp = &lp->data[offset];
-	left = lp->len - offset;
+	left = lp->len - offset - len;

-	while (left >= len) {
-	ncp = memchr(cp, *str, left);
+	while (left >= 0) {
+	ncp = memchr(cp, str[0], left + 1);
	if (ncp == NULL)
	return -1;
	left -= (ncp - cp);
-	if (left < len)
-	return -1;
	cp = ncp;
	if (memcmp(cp, str, len) == 0)
	return (cp - lp->data);
@@ -203,25 +194,23 @@ static NOINLINE int searchLines(const char *str, int num1, int num2)
	/*
	* Parse a line number argument if it is present. This is a sum
	* or difference of numbers, '.', '$', 'x, or a search string.
-	* Returns TRUE if successful (whether or not there was a number).
-	* Returns FALSE if there was a parsing error, with a message output.
+	* Returns pointer which stopped the scan if successful (whether or not
+	* there was a number).
+	* Returns NULL if there was a parsing error, with a message output.
	* Whether there was a number is returned indirectly, as is the number.
-	* The character pointer which stopped the scan is also returned.
	*/
-	static int getNum(const char *retcp, smallint retHaveNum, int *retNum)
+	static const char* getNum(const char cp, smallint retHaveNum, int *retNum)
	{
-	const char *cp;
	char *endStr, str[USERSIZE];
	int value, num;
	smallint haveNum, minus;

-	cp = *retcp;
	value = 0;
	haveNum = FALSE;
	minus = 0;

	while (TRUE) {
-	cp = skip_blank(cp);
+	cp = skip_whitespace(cp);

	switch (*cp) {
	case '.':
@@ -240,7 +229,7 @@ static int getNum(const char *retcp, smallint retHaveNum, int *retNum)
	cp++;
	if ((cp < 'a') \|\| (cp > 'z')) {
	bb_error_msg("bad mark name");
-	return FALSE;
+	return NULL;
	}
	haveNum = TRUE;
	num = marks[*cp++ - 'a'];
@@ -256,16 +245,15 @@ static int getNum(const char *retcp, smallint retHaveNum, int *retNum)
	cp = "";
	num = searchLines(str, curNum, lastNum);
	if (num == 0)
-	return FALSE;
+	return NULL;
	haveNum = TRUE;
	break;

	default:
	if (!isdigit(*cp)) {
-	*retcp = cp;
	*retHaveNum = haveNum;
	*retNum = value;
-	return TRUE;
+	return cp;
	}
	num = 0;
	while (isdigit(*cp))
@@ -276,7 +264,7 @@ static int getNum(const char *retcp, smallint retHaveNum, int *retNum)

	value += (minus ? -num : num);

-	cp = skip_blank(cp);
+	cp = skip_whitespace(cp);

	switch (*cp) {
	case '-':
@@ -290,10 +278,9 @@ static int getNum(const char *retcp, smallint retHaveNum, int *retNum)
	break;

	default:
-	*retcp = cp;
	*retHaveNum = haveNum;
	*retNum = value;
-	return TRUE;
+	return cp;
	}
	}
	}
@@ -789,12 +776,13 @@ static void subCommand(const char *cmd, int num1, int num2)
	*/
	static void doCommands(void)
	{
-	const char *cp;
-	char *endbuf, buf[USERSIZE];
-	int len, num1, num2;
-	smallint have1, have2;
-
	while (TRUE) {
+	char buf[USERSIZE];
+	const char *cp;
+	int len;
+	int n, num1, num2;
+	smallint h, have1, have2;
+
	/* Returns:
	* -1 on read errors or EOF, or on bare Ctrl-D.
	* 0 on ctrl-C,
@@ -803,32 +791,36 @@ static void doCommands(void)
	len = read_line_input(NULL, ": ", buf, sizeof(buf), /timeout/ -1);
	if (len <= 0)
	return;
-	endbuf = &buf[len - 1];
-	while ((endbuf > buf) && isblank(endbuf[-1]))
-	endbuf--;
-	*endbuf = '\0';
-
-	cp = skip_blank(buf);
-	have1 = FALSE;
-	have2 = FALSE;
+	while (len && isblank(buf[--len]))
+	buf[len] = '\0';

	if ((curNum == 0) && (lastNum > 0)) {
	curNum = 1;
	curLine = lines.next;
	}

-	if (!getNum(&cp, &have1, &num1))
+	have1 = FALSE;
+	have2 = FALSE;
+	/* Don't pass &have1, &num1 to getNum() since this forces
+	* compiler to keep them on stack, not in registers,
+	* which is usually quite suboptimal.
+	* Using intermediate variables shrinks code by ~150 bytes.
+	*/
+	cp = getNum(skip_whitespace(buf), &h, &n);
+	if (!cp)
	continue;
+	have1 = h;
+	num1 = n;

-	cp = skip_blank(cp);
-
+	cp = skip_whitespace(cp);
	if (*cp == ',') {
-	cp++;
-	if (!getNum(&cp, &have2, &num2))
+	cp = getNum(cp + 1, &h, &n);
+	if (!cp)
	continue;
+	num2 = n;
	if (!have1)
	num1 = 1;
-	if (!have2)
+	if (!h)
	num2 = lastNum;
	have1 = TRUE;
	have2 = TRUE;
@@ -857,7 +849,7 @@ static void doCommands(void)
	bb_error_msg("bad file command");
	break;
	}
-	cp = skip_blank(cp);
+	cp = skip_whitespace(cp);
	if (*cp == '\0') {
	if (fileName)
	printf("\"%s\"\n", fileName);
@@ -874,7 +866,7 @@ static void doCommands(void)
	break;

	case 'k':
-	cp = skip_blank(cp);
+	cp = skip_whitespace(cp);
	if ((cp < 'a') \|\| (cp > 'z') \|\| cp[1]) {
	bb_error_msg("bad mark name");
	break;
@@ -891,7 +883,7 @@ static void doCommands(void)
	break;

	case 'q':
-	cp = skip_blank(cp);
+	cp = skip_whitespace(cp);
	if (have1 \|\| *cp) {
	bb_error_msg("bad quit command");
	break;
@@ -902,7 +894,7 @@ static void doCommands(void)
	/* read error/EOF - no way to continue */
	if (len < 0)
	return;
-	cp = skip_blank(buf);
+	cp = skip_whitespace(buf);
	if ((cp \| 0x20) == 'y') / Y or y */
	return;
	break;
@@ -912,7 +904,7 @@ static void doCommands(void)
	bb_error_msg("bad read command");
	break;
	}
-	cp = skip_blank(cp);
+	cp = skip_whitespace(cp);
	if (*cp == '\0') {
	bb_error_msg("no file name");
	break;
@@ -934,7 +926,7 @@ static void doCommands(void)
	bb_error_msg("bad write command");
	break;
	}
-	cp = skip_blank(cp);
+	cp = skip_whitespace(cp);
	if (!have1) {
	num1 = 1;
	num2 = lastNum;