from forsyth

formalize the boostrapping process used to move the system to 32-bit runes
in a way that will allow the target system to have a smaller or bigger rune.

Reference: /n/atom/patch/applied/trune
Date: Sat Aug 15 23:42:03 CES 2015
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/cc/cc.h	Sat Aug 15 23:40:30 2015
+++ /sys/src/cmd/cc/cc.h	Sat Aug 15 23:40:31 2015
@@ -20,6 +20,8 @@
 typedef	struct	Init	Init;
 typedef	struct	Bits	Bits;
 
+typedef	Rune	TRune;	/* target system type */
+
 #define	NHUNK		50000L
 #define	BUFSIZ		8192
 #define	NSYMB		1500
@@ -51,7 +53,7 @@
 	double	fconst;		/* fp constant */
 	vlong	vconst;		/* non fp const */
 	char*	cstring;	/* character string */
-	Rune*	rstring;	/* rune string */
+	TRune*	rstring;	/* rune string */
 
 	Sym*	sym;
 	Type*	type;
@@ -337,11 +339,8 @@
 	TOLD,
 	NALLTYPES,
 
-	/*
-	 * bootstrapping
-	 */
-//	TRUNE = TUINT,
-	TRUNE = sizeof(Rune)==4? TUINT: TUSHORT,
+	/* adapt size of Rune to target system's size */
+	TRUNE = sizeof(TRune)==4? TUINT: TUSHORT,
 };
 enum
 {
@@ -747,7 +746,7 @@
 void	gextern(Sym*, Node*, long, long);
 void	ginit(void);
 long	outstring(char*, long);
-long	outlstring(Rune*, long);
+long	outlstring(TRune*, long);
 void	xcom(Node*);
 long	exreg(Type*);
 long	align(long, Type*, int);
--- /sys/src/cmd/cc/cc.y	Sat Aug 15 23:40:34 2015
+++ /sys/src/cmd/cc/cc.y	Sat Aug 15 23:40:35 2015
@@ -856,8 +856,8 @@
 	{
 		$$ = new(OLSTRING, Z, Z);
 		$$->type = typ(TARRAY, types[TRUNE]);
-		$$->type->width = $1.l + sizeof(Rune);
-		$$->rstring = (Rune*)$1.s;
+		$$->type->width = $1.l + sizeof(TRune);
+		$$->rstring = (TRune*)$1.s;
 		$$->sym = symstring;
 		$$->etype = TARRAY;
 		$$->class = CSTATIC;
@@ -867,16 +867,16 @@
 		char *s;
 		int n;
 
-		n = $1->type->width - sizeof(Rune);
+		n = $1->type->width - sizeof(TRune);
 		s = alloc(n+$2.l+MAXALIGN);
 
 		memcpy(s, $1->rstring, n);
 		memcpy(s+n, $2.s, $2.l);
-		*(Rune*)(s+n+$2.l) = 0;
+		*(TRune*)(s+n+$2.l) = 0;
 
 		$$ = $1;
 		$$->type->width += $2.l;
-		$$->rstring = (Rune*)s;
+		$$->rstring = (TRune*)s;
 	}
 
 zelist:
--- /sys/src/cmd/cc/com.c	Sat Aug 15 23:40:38 2015
+++ /sys/src/cmd/cc/com.c	Sat Aug 15 23:40:40 2015
@@ -67,6 +67,7 @@
 	Node *l, *r;
 	Type *t;
 	int o;
+	static TRune zer;
 
 	if(n == Z) {
 		diag(Z, "Z in tcom");
@@ -636,9 +637,7 @@
 		if(n->type->link != types[TRUNE]) {
 			o = outstring(0, 0);
 			while(o & 3) {
-				/* outlstring(L"", sizeof(Rune)); */
-				Rune str[1] = {0};
-				outlstring(str, sizeof(Rune));
+				outlstring(&zer, sizeof(TRune));
 				o = outlstring(0, 0);
 			}
 		}
@@ -1049,7 +1048,6 @@
 				r->fconst = 1e10;
 			}
 		}
-
 		if(n->op == OASLSHR || n->op == OASASHR || n->op == OASASHL)
 		if(r->op == OCONST) {
 			t = n->type->width * 8;	/* bits per byte */
--- /sys/src/cmd/cc/lex.c	Sat Aug 15 23:40:43 2015
+++ /sys/src/cmd/cc/lex.c	Sat Aug 15 23:40:44 2015
@@ -540,15 +540,15 @@
 			c = escchar('"', 1, 0);
 			if(c == EOF)
 				break;
-			cp = allocn(cp, c1, sizeof(Rune));
-			*(Rune*)(cp + c1) = c;
-			c1 += sizeof(Rune);
+			cp = allocn(cp, c1, sizeof(TRune));
+			*(TRune*)(cp + c1) = c;
+			c1 += sizeof(TRune);
 		}
 		yylval.sval.l = c1;
 		do {
-			cp = allocn(cp, c1, sizeof(Rune));
-			*(Rune*)(cp + c1) = 0;
-			c1 += sizeof(Rune);
+			cp = allocn(cp, c1, sizeof(TRune));
+			*(TRune*)(cp + c1) = 0;
+			c1 += sizeof(TRune);
 		} while(c1 & MAXALIGN);
 		yylval.sval.s = cp;
 		return LLSTRING;
--- /sys/src/cmd/cc/pswt.c	Sat Aug 15 23:40:46 2015
+++ /sys/src/cmd/cc/pswt.c	Sat Aug 15 23:40:47 2015
@@ -132,28 +132,29 @@
 }
 
 long
-outlstring(Rune *s, long n)
+outlstring(TRune *s, long n)
 {
-	char buf[sizeof(Rune)];
-	int c, i;
+	char buf[sizeof(TRune)];
+	uint c;
+	int i;
 	long r;
 
 	if(suppress)
 		return nstring;
-	while(nstring & (sizeof(Rune)-1))
+	while(nstring & (sizeof(TRune)-1))
 		outstring("", 1);
 	r = nstring;
 	while(n > 0) {
 		c = *s++;
 		if(align(0, types[TCHAR], Aarg1)) {
-			for(i = 0; i < sizeof(Rune); i++)
-				buf[i] = c>>8*(sizeof(Rune) - i - 1);
+			for(i = 0; i < sizeof(TRune); i++)
+				buf[i] = c>>8*(sizeof(TRune) - i - 1);
 		} else {
-			for(i = 0; i < sizeof(Rune); i++)
+			for(i = 0; i < sizeof(TRune); i++)
 				buf[i] = c>>8*i;
 		}
-		outstring(buf, sizeof(Rune));
-		n -= sizeof(Rune);
+		outstring(buf, sizeof(TRune));
+		n -= sizeof(TRune);
 	}
 	return r;
 }
--- /sys/src/cmd/cc/sub.c	Sat Aug 15 23:40:51 2015
+++ /sys/src/cmd/cc/sub.c	Sat Aug 15 23:40:53 2015
@@ -85,7 +85,10 @@
 		break;
 
 	case OLSTRING:
-		print(" \"%S\"", n->rstring);
+		if(sizeof(TRune) == sizeof(Rune))
+			print(" \"%S\"", (Rune*)n->rstring);
+		else
+			print(" \"...\"");
 		i = 0;
 		break;