6g, 6l, 8g, 8l: move read-only data to text segment

Changing 5g and 5l too, but it doesn't work yet.

R=ken2
CC=golang-dev
http://codereview.appspot.com/2136047

22 files changed, 228 insertions, 153 deletions

diff --git a/src/cmd/6g/gsubr.c b/src/cmd/6g/gsubr.c
index e368dcad5..abece5e50 100644
--- a/src/cmd/6g/gsubr.c
+++ b/src/cmd/6g/gsubr.c
@@ -147,6 +147,8 @@ ggloblnod(Node *nam, int32 width)
 	p->to.sym = S;
 	p->to.type = D_CONST;
 	p->to.offset = width;
+	if(nam->readonly)
+		p->from.scale = RODATA;
 }
 
 void
@@ -163,6 +165,7 @@ ggloblsym(Sym *s, int32 width, int dupok)
 	p->to.offset = width;
 	if(dupok)
 		p->from.scale = DUPOK;
+	p->from.scale |= RODATA;
 }
 
 int
diff --git a/src/cmd/6g/list.c b/src/cmd/6g/list.c
index 9194b1dab..24e8bc70b 100644
--- a/src/cmd/6g/list.c
+++ b/src/cmd/6g/list.c
@@ -47,13 +47,17 @@ Pconv(Fmt *fp)
 {
 	char str[STRINGSZ];
 	Prog *p;
+	char scale[40];
 
 	p = va_arg(fp->args, Prog*);
 	sconsize = 8;
+	scale[0] = '\0';
+	if(p->from.scale != 0 && (p->as == AGLOBL || p->as == ATEXT))
+		snprint(scale, sizeof scale, "%d,", p->from.scale);
 	switch(p->as) {
 	default:
-		snprint(str, sizeof(str), "%.4ld (%L) %-7A %D,%D",
-			p->loc, p->lineno, p->as, &p->from, &p->to);
+		snprint(str, sizeof(str), "%.4ld (%L) %-7A %D,%s%D",
+			p->loc, p->lineno, p->as, &p->from, scale, &p->to);
 		break;
 
 	case ADATA:
@@ -63,8 +67,8 @@ Pconv(Fmt *fp)
 		break;
 
 	case ATEXT:
-		snprint(str, sizeof(str), "%.4ld (%L) %-7A %D,%lD",
-			p->loc, p->lineno, p->as, &p->from, &p->to);
+		snprint(str, sizeof(str), "%.4ld (%L) %-7A %D,%s%lD",
+			p->loc, p->lineno, p->as, &p->from, scale, &p->to);
 		break;
 	}
 	return fmtstrcpy(fp, str);
diff --git a/src/cmd/6l/6.out.h b/src/cmd/6l/6.out.h
index ca5e485c0..fdcd3f87b 100644
--- a/src/cmd/6l/6.out.h
+++ b/src/cmd/6l/6.out.h
@@ -33,6 +33,7 @@
 #define NOPROF	(1<<0)
 #define DUPOK	(1<<1)
 #define NOSPLIT	(1<<2)
+#define RODATA	(1<<3)
 
 /*
  *	amd64
diff --git a/src/cmd/6l/asm.c b/src/cmd/6l/asm.c
index 256213fe2..e86f51674 100644
--- a/src/cmd/6l/asm.c
+++ b/src/cmd/6l/asm.c
@@ -136,16 +136,16 @@ addstring(Sym *s, char *str)
 	if(s->type == 0)
 		s->type = SDATA;
 	s->reachable = 1;
-	r = s->value;
+	r = s->size;
 	n = strlen(str)+1;
 	while(n > 0) {
 		m = n;
 		if(m > sizeof(p->to.scon))
 			m = sizeof(p->to.scon);
-		p = newdata(s, s->value, m, D_EXTERN);
+		p = newdata(s, s->size, m, D_EXTERN);
 		p->to.type = D_SCONST;
 		memmove(p->to.scon, str, m);
-		s->value += m;
+		s->size += m;
 		str += m;
 		n -= m;
 	}
@@ -161,9 +161,9 @@ adduintxx(Sym *s, uint64 v, int wid)
 	if(s->type == 0)
 		s->type = SDATA;
 	s->reachable = 1;
-	r = s->value;
-	p = newdata(s, s->value, wid, D_EXTERN);
-	s->value += wid;
+	r = s->size;
+	p = newdata(s, s->size, wid, D_EXTERN);
+	s->size += wid;
 	p->to.type = D_CONST;
 	p->to.offset = v;
 	return r;
@@ -203,9 +203,9 @@ addaddr(Sym *s, Sym *t)
 	if(s->type == 0)
 		s->type = SDATA;
 	s->reachable = 1;
-	r = s->value;
-	p = newdata(s, s->value, Ptrsize, D_EXTERN);
-	s->value += Ptrsize;
+	r = s->size;
+	p = newdata(s, s->size, Ptrsize, D_EXTERN);
+	s->size += Ptrsize;
 	p->to.type = D_ADDR;
 	p->to.index = D_EXTERN;
 	p->to.offset = 0;
@@ -223,9 +223,9 @@ addsize(Sym *s, Sym *t)
 	if(s->type == 0)
 		s->type = SDATA;
 	s->reachable = 1;
-	r = s->value;
-	p = newdata(s, s->value, Ptrsize, D_EXTERN);
-	s->value += Ptrsize;
+	r = s->size;
+	p = newdata(s, s->size, Ptrsize, D_EXTERN);
+	s->size += Ptrsize;
 	p->to.type = D_SIZE;
 	p->to.index = D_EXTERN;
 	p->to.offset = 0;
@@ -321,13 +321,12 @@ doelf(void)
 		s = lookup(".dynsym", 0);
 		s->type = SELFDATA;
 		s->reachable = 1;
-		s->value += ELF64SYMSIZE;
+		s->size += ELF64SYMSIZE;
 
 		/* dynamic string table */
 		s = lookup(".dynstr", 0);
 		s->type = SELFDATA;
 		s->reachable = 1;
-		s->value += ELF64SYMSIZE;
 		addstring(s, "");
 		dynstr = s;
 
@@ -467,7 +466,7 @@ asmb(void)
 	int32 v, magic;
 	int a, dynsym;
 	uchar *op1;
-	vlong vl, va, startva, fo, w, symo, elfsymo, elfstro, elfsymsize, machlink;
+	vlong vl, va, startva, fo, w, symo, elfsymo, elfstro, elfsymsize, machlink, etext;
 	vlong symdatva = SYMDATVA;
 	ElfEhdr *eh;
 	ElfPhdr *ph, *pph;
@@ -519,6 +518,16 @@ asmb(void)
 	}
 	cflush();
 
+	datap = datsort(datap);
+
+	/* output read-only data in text segment */
+	etext = INITTEXT + textsize;
+	for(v = pc; v < etext; v += sizeof(buf)-Dbufslop) {
+		if(etext - v > sizeof(buf)-Dbufslop)
+			datblk(v, sizeof(buf)-Dbufslop);
+		else
+			datblk(v, etext-v);
+	}
 
 	switch(HEADTYPE) {
 	default:
@@ -564,12 +573,11 @@ asmb(void)
 		textsize = INITDAT;
 	}
 
-	datap = datsort(datap);
 	for(v = 0; v < datsize; v += sizeof(buf)-Dbufslop) {
 		if(datsize-v > sizeof(buf)-Dbufslop)
-			datblk(v, sizeof(buf)-Dbufslop);
+			datblk(v+INITDAT, sizeof(buf)-Dbufslop);
 		else
-			datblk(v, datsize-v);
+			datblk(v+INITDAT, datsize-v);
 	}
 
 	machlink = 0;
@@ -1102,6 +1110,8 @@ datsort(Prog *l)
 	for(p = l; p != P; p = p->link) {
 		a = &p->from;
 		a->offset += a->sym->value;
+		if(a->sym->type != SRODATA)
+			a->offset += INITDAT;
 	}
 	datp = dsort(l);
 	return datp;
@@ -1202,10 +1212,10 @@ datblk(int32 s, int32 n)
 						diag("missing symbol %s", p->to.sym->name);
 					}
 					o += p->to.sym->value;
-					if(p->to.sym->type != STEXT && p->to.sym->type != SUNDEF)
+					if(p->to.sym->type != STEXT && p->to.sym->type != SUNDEF && p->to.sym->type != SRODATA)
 						o += INITDAT;
 					if(dlm)
-						dynreloc(p->to.sym, l+s+INITDAT, 1);
+						dynreloc(p->to.sym, l+s, 1);
 				}
 			}
 			fl = o;
@@ -1266,6 +1276,7 @@ datblk(int32 s, int32 n)
 		if(a->sym->type == SMACHO)
 			continue;
 
+		curp = p;
 		switch(p->to.type) {
 		case D_FCONST:
 			switch(c) {
@@ -1273,17 +1284,17 @@ datblk(int32 s, int32 n)
 			case 4:
 				fl = ieeedtof(&p->to.ieee);
 				cast = (uchar*)&fl;
-				outa(c, cast, fnuxi4, l+s+INITDAT);
+				outa(c, cast, fnuxi4, l+s);
 				break;
 			case 8:
 				cast = (uchar*)&p->to.ieee;
-				outa(c, cast, fnuxi8, l+s+INITDAT);
+				outa(c, cast, fnuxi8, l+s);
 				break;
 			}
 			break;
 
 		case D_SCONST:
-			outa(c, (uchar*)p->to.scon, nil, l+s+INITDAT);
+			outa(c, (uchar*)p->to.scon, nil, l+s);
 			break;
 
 		default:
@@ -1293,7 +1304,7 @@ datblk(int32 s, int32 n)
 			if(p->to.type == D_ADDR) {
 				if(p->to.sym) {
 					o += p->to.sym->value;
-					if(p->to.sym->type != STEXT && p->to.sym->type != SUNDEF)
+					if(p->to.sym->type != STEXT && p->to.sym->type != SUNDEF && p->to.sym->type != SRODATA)
 						o += INITDAT;
 				}
 			}
@@ -1301,17 +1312,17 @@ datblk(int32 s, int32 n)
 			cast = (uchar*)&fl;
 			switch(c) {
 			case 1:
-				outa(c, cast, inuxi1, l+s+INITDAT);
+				outa(c, cast, inuxi1, l+s);
 				break;
 			case 2:
-				outa(c, cast, inuxi2, l+s+INITDAT);
+				outa(c, cast, inuxi2, l+s);
 				break;
 			case 4:
-				outa(c, cast, inuxi4, l+s+INITDAT);
+				outa(c, cast, inuxi4, l+s);
 				break;
 			case 8:
 				cast = (uchar*)&o;
-				outa(c, cast, inuxi8, l+s+INITDAT);
+				outa(c, cast, inuxi8, l+s);
 				break;
 			}
 			break;
diff --git a/src/cmd/6l/l.h b/src/cmd/6l/l.h
index a8428865a..22f266fe4 100644
--- a/src/cmd/6l/l.h
+++ b/src/cmd/6l/l.h
@@ -169,6 +169,7 @@ enum
 	SMACHO,
 	SFIXED,
 	SELFDATA,
+	SRODATA,
 
 	NHASH		= 10007,
 	NHUNK		= 100000,
diff --git a/src/cmd/6l/list.c b/src/cmd/6l/list.c
index 195e11d1d..d1ecabbc4 100644
--- a/src/cmd/6l/list.c
+++ b/src/cmd/6l/list.c
@@ -47,41 +47,30 @@ listinit(void)
 int
 Pconv(Fmt *fp)
 {
-	char str[STRINGSZ], str1[STRINGSZ];
 	Prog *p;
 
 	p = va_arg(fp->args, Prog*);
-	if(p == P)
-		return fmtstrcpy(fp, "<P>");
-
 	bigP = p;
-
-	snprint(str1, sizeof(str1), "(%ld)", p->line);
 	switch(p->as) {
 	case ATEXT:
 		if(p->from.scale) {
-			snprint(str, sizeof(str), "%-7s %-7A %D,%d,%lD",
-				str1, p->as, &p->from, p->from.scale, &p->to);
+			fmtprint(fp, "(%d)	%A	%D,%d,%D",
+				p->line, p->as, &p->from, p->from.scale, &p->to);
 			break;
 		}
-		snprint(str, sizeof(str), "%-7s %-7A %D,%lD",
-			str1, p->as, &p->from, &p->to);
-		break;
-
 	default:
-		snprint(str, sizeof(str), "%-7s %-7A %D,%D",
-			str1, p->as, &p->from, &p->to);
+		fmtprint(fp, "(%d)	%A	%D,%D",
+			p->line, p->as, &p->from, &p->to);
 		break;
-
 	case ADATA:
 	case AINIT:
 	case ADYNT:
-		snprint(str, sizeof(str), "%-7s %-7A %D/%d,%D",
-			str1, p->as, &p->from, p->from.scale, &p->to);
+		fmtprint(fp, "(%d)	%A	%D/%d,%D",
+			p->line, p->as, &p->from, p->from.scale, &p->to);
 		break;
 	}
 	bigP = P;
-	return fmtstrcpy(fp, str);
+	return 0;
 }
 
 int
diff --git a/src/cmd/6l/obj.c b/src/cmd/6l/obj.c
index adcccb55a..da2630e63 100644
--- a/src/cmd/6l/obj.c
+++ b/src/cmd/6l/obj.c
@@ -633,18 +633,20 @@ loop:
 		s = p->from.sym;
 		if(s->type == 0 || s->type == SXREF) {
 			s->type = SBSS;
-			s->value = 0;
+			s->size = 0;
 		}
-		if(s->type != SBSS) {
+		if(s->type != SBSS && !s->dupok) {
 			diag("%s: redefinition: %s in %s",
 				pn, s->name, TNAME);
 			s->type = SBSS;
-			s->value = 0;
+			s->size = 0;
 		}
-		if(p->to.offset > s->value)
-			s->value = p->to.offset;
+		if(p->to.offset > s->size)
+			s->size = p->to.offset;
 		if(p->from.scale & DUPOK)
 			s->dupok = 1;
+		if(p->from.scale & RODATA)
+			s->type = SRODATA;
 		goto loop;
 
 	case ADYNT:
@@ -791,7 +793,7 @@ loop:
 			s = lookup(literal, 0);
 			if(s->type == 0) {
 				s->type = SBSS;
-				s->value = 4;
+				s->size = 4;
 				t = prg();
 				t->as = ADATA;
 				t->line = p->line;
@@ -837,7 +839,7 @@ loop:
 			s = lookup(literal, 0);
 			if(s->type == 0) {
 				s->type = SBSS;
-				s->value = 8;
+				s->size = 8;
 				t = prg();
 				t->as = ADATA;
 				t->line = p->line;
@@ -967,7 +969,7 @@ doprof1(void)
 	q->to.offset = n;
 
 	s->type = SBSS;
-	s->value = n*4;
+	s->size = n*4;
 }
 
 void
diff --git a/src/cmd/6l/pass.c b/src/cmd/6l/pass.c
index 5fedee24a..275844c9b 100644
--- a/src/cmd/6l/pass.c
+++ b/src/cmd/6l/pass.c
@@ -56,13 +56,13 @@ dodata(void)
 			s->value = dtype;
 		if(s->type == SBSS)
 			s->type = SDATA;
-		if(s->type != SDATA && s->type != SELFDATA)
+		if(s->type != SDATA && s->type != SELFDATA && s->type != SRODATA)
 			diag("initialize non-data (%d): %s\n%P",
 				s->type, s->name, p);
 		t = p->from.offset + p->width;
-		if(t > s->value)
+		if(t > s->size)
 			diag("initialize bounds (%lld): %s\n%P",
-				s->value, s->name, p);
+				s->size, s->name, p);
 	}
 
 	/* allocate elf guys - must be segregated from real data */
@@ -73,7 +73,7 @@ dodata(void)
 			continue;
 		if(s->type != SELFDATA)
 			continue;
-		t = rnd(s->value, 8);
+		t = rnd(s->size, 8);
 		s->size = t;
 		s->value = datsize;
 		datsize += t;
@@ -88,13 +88,12 @@ dodata(void)
 		if(s->type != SDATA)
 		if(s->type != SBSS)
 			continue;
-		t = s->value;
+		t = s->size;
 		if(t == 0 && s->name[0] != '.') {
 			diag("%s: no size", s->name);
 			t = 1;
 		}
 		t = rnd(t, 4);
-		s->value = t;
 		if(t > MINSIZ)
 			continue;
 		if(t >= 8)
@@ -115,10 +114,9 @@ dodata(void)
 				s->type = SDATA;
 			continue;
 		}
-		t = s->value;
+		t = s->size;
 		if(t >= 8)
 			datsize = rnd(datsize, 8);
-		s->size = t;
 		s->value = datsize;
 		datsize += t;
 	}
@@ -171,8 +169,7 @@ dobss(void)
 			continue;
 		if(s->type != SBSS)
 			continue;
-		t = s->value;
-		s->size = t;
+		t = s->size;
 		if(t >= 8)
 			bsssize = rnd(bsssize, 8);
 		s->value = bsssize + dynptrsize + datsize;
@@ -1164,10 +1161,10 @@ export(void)
 		newdata(et, off, sizeof(int32), D_EXTERN);
 		off += sizeof(int32);
 	}
-	et->value = off;
+	et->size = off;
 	if(sv == 0)
 		sv = 1;
-	str->value = sv;
+	str->size = sv;
 	exports = ne;
 	free(esyms);
 }
diff --git a/src/cmd/6l/span.c b/src/cmd/6l/span.c
index 7e0086e93..2da3656f1 100644
--- a/src/cmd/6l/span.c
+++ b/src/cmd/6l/span.c
@@ -39,9 +39,10 @@ void
 span(void)
 {
 	Prog *p, *q;
-	int32 v;
+	int32 i, v;
 	vlong c, idat;
 	int m, n, again;
+	Sym *s;
 
 	xdefine("etext", STEXT, 0L);
 	idat = INITDAT;
@@ -121,6 +122,22 @@ loop:
 		textsize = c;
 		goto loop;
 	}
+	
+	/*
+	 * allocate read-only data to the text segment.
+	 */
+	c = rnd(c, 8);
+	for(i=0; i<NHASH; i++)
+	for(s = hash[i]; s != S; s = s->link) {
+		if(s->type != SRODATA)
+			continue;
+		v = s->size;
+		while(v & 7)
+			v++;
+		s->value = c;
+		c += v;
+	}
+
 	if(INITRND) {
 		INITDAT = rnd(c, INITRND);
 		if(INITDAT != idat) {
@@ -128,6 +145,7 @@ loop:
 			goto start;
 		}
 	}
+
 	xdefine("etext", STEXT, c);
 	if(debug['v'])
 		Bprint(&bso, "etext = %llux\n", c);
@@ -228,6 +246,7 @@ genasmsym(void (*put)(char*, int, vlong, vlong, int, Sym*))
 		for(s=hash[h]; s!=S; s=s->link) {
 			switch(s->type) {
 			case SCONST:
+			case SRODATA:
 				if(!s->reachable)
 					continue;
 				put(s->name, 'D', s->value, s->size, s->version, s->gotype);
@@ -809,6 +828,7 @@ vaddr(Adr *a)
 				ckoff(s, v);
 			case STEXT:
 			case SCONST:
+			case SRODATA:
 				if(!s->reachable)
 					diag("unreachable symbol in vaddr - %s", s->name);
 				if((uvlong)s->value < (uvlong)INITTEXT)
diff --git a/src/cmd/8g/gsubr.c b/src/cmd/8g/gsubr.c
index a63d03e66..42794a578 100644
--- a/src/cmd/8g/gsubr.c
+++ b/src/cmd/8g/gsubr.c
@@ -149,6 +149,8 @@ ggloblnod(Node *nam, int32 width)
 	p->to.sym = S;
 	p->to.type = D_CONST;
 	p->to.offset = width;
+	if(nam->readonly)
+		p->from.scale = RODATA;
 }
 
 void
@@ -165,6 +167,7 @@ ggloblsym(Sym *s, int32 width, int dupok)
 	p->to.offset = width;
 	if(dupok)
 		p->from.scale = DUPOK;
+	p->from.scale |= RODATA;
 }
 
 int
diff --git a/src/cmd/8g/list.c b/src/cmd/8g/list.c
index 9b3622a6d..7438a6521 100644
--- a/src/cmd/8g/list.c
+++ b/src/cmd/8g/list.c
@@ -47,13 +47,17 @@ Pconv(Fmt *fp)
 {
 	char str[STRINGSZ];
 	Prog *p;
+	char scale[40];
 
 	p = va_arg(fp->args, Prog*);
 	sconsize = 8;
+	scale[0] = '\0';
+	if(p->from.scale != 0 && (p->as == AGLOBL || p->as == ATEXT))
+		snprint(scale, sizeof scale, "%d,", p->from.scale);
 	switch(p->as) {
 	default:
-		snprint(str, sizeof(str), "%.4ld (%L) %-7A %D,%D",
-			p->loc, p->lineno, p->as, &p->from, &p->to);
+		snprint(str, sizeof(str), "%.4ld (%L) %-7A %D,%s%D",
+			p->loc, p->lineno, p->as, &p->from, scale, &p->to);
 		break;
 
 	case ADATA:
@@ -63,8 +67,8 @@ Pconv(Fmt *fp)
 		break;
 
 	case ATEXT:
-		snprint(str, sizeof(str), "%.4ld (%L) %-7A %D,%lD",
-			p->loc, p->lineno, p->as, &p->from, &p->to);
+		snprint(str, sizeof(str), "%.4ld (%L) %-7A %D,%s%lD",
+			p->loc, p->lineno, p->as, &p->from, scale, &p->to);
 		break;
 	}
 	return fmtstrcpy(fp, str);
diff --git a/src/cmd/8l/8.out.h b/src/cmd/8l/8.out.h
index c17f606e2..4e3022653 100644
--- a/src/cmd/8l/8.out.h
+++ b/src/cmd/8l/8.out.h
@@ -33,6 +33,7 @@
 #define NOPROF	(1<<0)
 #define DUPOK	(1<<1)
 #define NOSPLIT	(1<<2)
+#define RODATA	(1<<3)
 
 enum	as
 {
diff --git a/src/cmd/8l/asm.c b/src/cmd/8l/asm.c
index 89d0fca3c..4d5417b4f 100644
--- a/src/cmd/8l/asm.c
+++ b/src/cmd/8l/asm.c
@@ -127,16 +127,16 @@ addstring(Sym *s, char *str)
 	if(s->type == 0)
 		s->type = SDATA;
 	s->reachable = 1;
-	r = s->value;
+	r = s->size;
 	n = strlen(str)+1;
 	while(n > 0) {
 		m = n;
 		if(m > sizeof(p->to.scon))
 			m = sizeof(p->to.scon);
-		p = newdata(s, s->value, m, D_EXTERN);
+		p = newdata(s, s->size, m, D_EXTERN);
 		p->to.type = D_SCONST;
 		memmove(p->to.scon, str, m);
-		s->value += m;
+		s->size += m;
 		str += m;
 		n -= m;
 	}
@@ -152,9 +152,9 @@ adduintxx(Sym *s, uint64 v, int wid)
 	if(s->type == 0)
 		s->type = SDATA;
 	s->reachable = 1;
-	r = s->value;
-	p = newdata(s, s->value, wid, D_EXTERN);
-	s->value += wid;
+	r = s->size;
+	p = newdata(s, s->size, wid, D_EXTERN);
+	s->size += wid;
 	p->to.type = D_CONST;
 	p->to.offset = v;
 	return r;
@@ -194,9 +194,9 @@ addaddr(Sym *s, Sym *t)
 	if(s->type == 0)
 		s->type = SDATA;
 	s->reachable = 1;
-	r = s->value;
-	p = newdata(s, s->value, Ptrsize, D_EXTERN);
-	s->value += Ptrsize;
+	r = s->size;
+	p = newdata(s, s->size, Ptrsize, D_EXTERN);
+	s->size += Ptrsize;
 	p->to.type = D_ADDR;
 	p->to.index = D_EXTERN;
 	p->to.offset = 0;
@@ -214,9 +214,9 @@ addsize(Sym *s, Sym *t)
 	if(s->type == 0)
 		s->type = SDATA;
 	s->reachable = 1;
-	r = s->value;
-	p = newdata(s, s->value, Ptrsize, D_EXTERN);
-	s->value += Ptrsize;
+	r = s->size;
+	p = newdata(s, s->size, Ptrsize, D_EXTERN);
+	s->size += Ptrsize;
 	p->to.type = D_SIZE;
 	p->to.index = D_EXTERN;
 	p->to.offset = 0;
@@ -317,7 +317,7 @@ doelf(void)
 		s = lookup(".dynsym", 0);
 		s->type = SELFDATA;
 		s->reachable = 1;
-		s->value += ELF32SYMSIZE;
+		s->size += ELF32SYMSIZE;
 
 		/* dynamic string table */
 		s = lookup(".dynstr", 0);
@@ -455,7 +455,7 @@ asmb(void)
 	Prog *p;
 	int32 v, magic;
 	int a, dynsym;
-	uint32 va, fo, w, symo, startva, machlink;
+	uint32 va, fo, w, symo, startva, machlink, etext;
 	uchar *op1;
 	ulong expectpc;
 	ElfEhdr *eh;
@@ -529,6 +529,15 @@ asmb(void)
 		}
 	}
 	cflush();
+	
+	/* output read-only data in text segment */
+	etext = INITTEXT + textsize;
+	for(v = pc; v < etext; v += sizeof(buf)-Dbufslop) {
+		if(etext-v > sizeof(buf)-Dbufslop)
+			datblk(v, sizeof(buf)-Dbufslop, 1);
+		else
+			datblk(v, etext-v, 1);
+	}
 
 	switch(HEADTYPE) {
 	default:
@@ -587,9 +596,9 @@ asmb(void)
 
 	for(v = 0; v < datsize; v += sizeof(buf)-Dbufslop) {
 		if(datsize-v > sizeof(buf)-Dbufslop)
-			datblk(v, sizeof(buf)-Dbufslop);
+			datblk(v, sizeof(buf)-Dbufslop, 0);
 		else
-			datblk(v, datsize-v);
+			datblk(v, datsize-v, 0);
 	}
 
 	machlink = 0;
@@ -1135,17 +1144,24 @@ cpos(void)
 }
 
 void
-datblk(int32 s, int32 n)
+datblk(int32 s, int32 n, int32 rodata)
 {
 	Prog *p;
 	char *cast;
 	int32 l, fl, j;
 	int i, c;
 	Adr *a;
+	int32 base;
+	
+	base = INITDAT;
+	if(rodata)
+		base = 0;
 
 	memset(buf.dbuf, 0, n+Dbufslop);
 	for(p = datap; p != P; p = p->link) {
 		a = &p->from;
+		if(rodata != (a->sym->type == SRODATA))
+			continue;
 
 		l = a->sym->value + a->offset - s;
 		if(l >= n)
@@ -1214,7 +1230,7 @@ datblk(int32 s, int32 n)
 					if(p->to.sym->type == SUNDEF)
 						ckoff(p->to.sym, fl);
 					fl += p->to.sym->value;
-					if(p->to.sym->type != STEXT && p->to.sym->type != SUNDEF)
+					if(p->to.sym->type != STEXT && p->to.sym->type != SUNDEF && p->to.sym->type != SRODATA)
 						fl += INITDAT;
 					if(dlm)
 						dynreloc(p->to.sym, l+s+INITDAT, 1);
@@ -1257,6 +1273,8 @@ datblk(int32 s, int32 n)
 	 */
 	for(p = datap; p != P; p = p->link) {
 		a = &p->from;
+		if(rodata != (a->sym->type == SRODATA))
+			continue;
 
 		l = a->sym->value + a->offset - s;
 		if(l < 0 || l >= n)
@@ -1272,26 +1290,26 @@ datblk(int32 s, int32 n)
 			case 4:
 				fl = ieeedtof(&p->to.ieee);
 				cast = (char*)&fl;
-				Bprint(&bso, pcstr, l+s+INITDAT);
+				Bprint(&bso, pcstr, l+s+base);
 				for(j=0; j<c; j++)
 					Bprint(&bso, "%.2ux", cast[fnuxi4[j]] & 0xff);
-				Bprint(&bso, "\t%P\n", curp);
+				Bprint(&bso, "\t%P\n", p);
 				break;
 			case 8:
 				cast = (char*)&p->to.ieee;
-				Bprint(&bso, pcstr, l+s+INITDAT);
+				Bprint(&bso, pcstr, l+s+base);
 				for(j=0; j<c; j++)
 					Bprint(&bso, "%.2ux", cast[fnuxi8[j]] & 0xff);
-				Bprint(&bso, "\t%P\n", curp);
+				Bprint(&bso, "\t%P\n", p);
 				break;
 			}
 			break;
 
 		case D_SCONST:
-			Bprint(&bso, pcstr, l+s+INITDAT);
+			Bprint(&bso, pcstr, l+s+base);
 			for(j=0; j<c; j++)
 				Bprint(&bso, "%.2ux", p->to.scon[j] & 0xff);
-			Bprint(&bso, "\t%P\n", curp);
+			Bprint(&bso, "\t%P\n", p);
 			break;
 
 		default:
@@ -1305,34 +1323,34 @@ datblk(int32 s, int32 n)
 					if(p->to.sym->type == SUNDEF)
 						ckoff(p->to.sym, fl);
 					fl += p->to.sym->value;
-					if(p->to.sym->type != STEXT && p->to.sym->type != SUNDEF)
+					if(p->to.sym->type != STEXT && p->to.sym->type != SUNDEF && p->to.sym->type != SRODATA)
 						fl += INITDAT;
 					if(dlm)
-						dynreloc(p->to.sym, l+s+INITDAT, 1);
+						dynreloc(p->to.sym, l+s+base, 1);
 				}
 			}
 			cast = (char*)&fl;
 			switch(c) {
 			default:
-				diag("bad nuxi %d %d\n%P", c, i, curp);
+				diag("bad nuxi %d %d\n%P", c, i, p);
 				break;
 			case 1:
-				Bprint(&bso, pcstr, l+s+INITDAT);
+				Bprint(&bso, pcstr, l+s+base);
 				for(j=0; j<c; j++)
 					Bprint(&bso, "%.2ux", cast[inuxi1[j]] & 0xff);
-				Bprint(&bso, "\t%P\n", curp);
+				Bprint(&bso, "\t%P\n", p);
 				break;
 			case 2:
-				Bprint(&bso, pcstr, l+s+INITDAT);
+				Bprint(&bso, pcstr, l+s+base);
 				for(j=0; j<c; j++)
 					Bprint(&bso, "%.2ux", cast[inuxi2[j]] & 0xff);
-				Bprint(&bso, "\t%P\n", curp);
+				Bprint(&bso, "\t%P\n", p);
 				break;
 			case 4:
-				Bprint(&bso, pcstr, l+s+INITDAT);
+				Bprint(&bso, pcstr, l+s+base);
 				for(j=0; j<c; j++)
 					Bprint(&bso, "%.2ux", cast[inuxi4[j]] & 0xff);
-				Bprint(&bso, "\t%P\n", curp);
+				Bprint(&bso, "\t%P\n", p);
 				break;
 			}
 			break;
diff --git a/src/cmd/8l/l.h b/src/cmd/8l/l.h
index 32ead12ef..e3b53f202 100644
--- a/src/cmd/8l/l.h
+++ b/src/cmd/8l/l.h
@@ -163,6 +163,7 @@ enum
 
 	SFIXED,
 	SELFDATA,
+	SRODATA,
 
 	NHASH		= 10007,
 	NHUNK		= 100000,
@@ -347,7 +348,7 @@ void	ckoff(Sym*, int32);
 Prog*	copyp(Prog*);
 vlong   cpos(void);
 double	cputime(void);
-void	datblk(int32, int32);
+void	datblk(int32, int32, int32);
 void	diag(char*, ...);
 void	dodata(void);
 void	doelf(void);
diff --git a/src/cmd/8l/list.c b/src/cmd/8l/list.c
index e665992a3..85f3da6d6 100644
--- a/src/cmd/8l/list.c
+++ b/src/cmd/8l/list.c
@@ -47,7 +47,6 @@ static	Prog	*bigP;
 int
 Pconv(Fmt *fp)
 {
-	char str[STRINGSZ];
 	Prog *p;
 
 	p = va_arg(fp->args, Prog*);
@@ -55,23 +54,23 @@ Pconv(Fmt *fp)
 	switch(p->as) {
 	case ATEXT:
 		if(p->from.scale) {
-			sprint(str, "(%d)	%A	%D,%d,%D",
+			fmtprint(fp, "(%d)	%A	%D,%d,%D",
 				p->line, p->as, &p->from, p->from.scale, &p->to);
 			break;
 		}
 	default:
-		sprint(str, "(%d)	%A	%D,%D",
+		fmtprint(fp, "(%d)	%A	%D,%D",
 			p->line, p->as, &p->from, &p->to);
 		break;
 	case ADATA:
 	case AINIT:
 	case ADYNT:
-		sprint(str, "(%d)	%A	%D/%d,%D",
+		fmtprint(fp, "(%d)	%A	%D/%d,%D",
 			p->line, p->as, &p->from, p->from.scale, &p->to);
 		break;
 	}
 	bigP = P;
-	return fmtstrcpy(fp, str);
+	return 0;
 }
 
 int
@@ -102,15 +101,15 @@ Dconv(Fmt *fp)
 	i = a->type;
 	if(i >= D_INDIR && i < 2*D_INDIR) {
 		if(a->offset)
-			sprint(str, "%ld(%R)", (long)a->offset, i-D_INDIR);
+			snprint(str, sizeof str, "%ld(%R)", (long)a->offset, i-D_INDIR);
 		else
-			sprint(str, "(%R)", i-D_INDIR);
+			snprint(str, sizeof str, "(%R)", i-D_INDIR);
 		goto brk;
 	}
 	switch(i) {
 
 	default:
-		sprint(str, "%R", i);
+		snprint(str, sizeof str, "%R", i);
 		break;
 
 	case D_NONE:
@@ -120,54 +119,54 @@ Dconv(Fmt *fp)
 	case D_BRANCH:
 		if(bigP != P && bigP->pcond != P)
 			if(a->sym != S)
-				sprint(str, "%lux+%s", bigP->pcond->pc,
+				snprint(str, sizeof str, "%lux+%s", bigP->pcond->pc,
 					a->sym->name);
 			else
-				sprint(str, "%lux", bigP->pcond->pc);
+				snprint(str, sizeof str, "%lux", bigP->pcond->pc);
 		else
-			sprint(str, "%ld(PC)", a->offset);
+			snprint(str, sizeof str, "%ld(PC)", a->offset);
 		break;
 
 	case D_EXTERN:
-		sprint(str, "%s+%ld(SB)", xsymname(a->sym), a->offset);
+		snprint(str, sizeof str, "%s+%ld(SB)", xsymname(a->sym), a->offset);
 		break;
 
 	case D_STATIC:
-		sprint(str, "%s<%d>+%ld(SB)", xsymname(a->sym),
+		snprint(str, sizeof str, "%s<%d>+%ld(SB)", xsymname(a->sym),
 			a->sym->version, a->offset);
 		break;
 
 	case D_AUTO:
-		sprint(str, "%s+%ld(SP)", xsymname(a->sym), a->offset);
+		snprint(str, sizeof str, "%s+%ld(SP)", xsymname(a->sym), a->offset);
 		break;
 
 	case D_PARAM:
 		if(a->sym)
-			sprint(str, "%s+%ld(FP)", a->sym->name, a->offset);
+			snprint(str, sizeof str, "%s+%ld(FP)", a->sym->name, a->offset);
 		else
-			sprint(str, "%ld(FP)", a->offset);
+			snprint(str, sizeof str, "%ld(FP)", a->offset);
 		break;
 
 	case D_CONST:
-		sprint(str, "$%ld", a->offset);
+		snprint(str, sizeof str, "$%ld", a->offset);
 		break;
 
 	case D_CONST2:
-		sprint(str, "$%ld-%ld", a->offset, a->offset2);
+		snprint(str, sizeof str, "$%ld-%ld", a->offset, a->offset2);
 		break;
 
 	case D_FCONST:
-		sprint(str, "$(%.8lux,%.8lux)", a->ieee.h, a->ieee.l);
+		snprint(str, sizeof str, "$(%.8lux,%.8lux)", a->ieee.h, a->ieee.l);
 		break;
 
 	case D_SCONST:
-		sprint(str, "$\"%S\"", a->scon);
+		snprint(str, sizeof str, "$\"%S\"", a->scon);
 		break;
 
 	case D_ADDR:
 		a->type = a->index;
 		a->index = D_NONE;
-		sprint(str, "$%D", a);
+		snprint(str, sizeof str, "$%D", a);
 		a->index = a->type;
 		a->type = D_ADDR;
 		goto conv;
diff --git a/src/cmd/8l/obj.c b/src/cmd/8l/obj.c
index 241b4d6b7..006189444 100644
--- a/src/cmd/8l/obj.c
+++ b/src/cmd/8l/obj.c
@@ -432,7 +432,7 @@ zsym(char *pn, Biobuf *f, Sym *h[])
 void
 zaddr(char *pn, Biobuf *f, Adr *a, Sym *h[])
 {
-	int o, t;
+	int t;
 	int32 l;
 	Sym *s;
 	Auto *u;
@@ -652,18 +652,20 @@ loop:
 		s = p->from.sym;
 		if(s->type == 0 || s->type == SXREF) {
 			s->type = SBSS;
-			s->value = 0;
+			s->size = 0;
 		}
-		if(s->type != SBSS) {
+		if(s->type != SBSS && !s->dupok) {
 			diag("%s: redefinition: %s in %s",
 				pn, s->name, TNAME);
 			s->type = SBSS;
-			s->value = 0;
+			s->size = 0;
 		}
-		if(p->to.offset > s->value)
-			s->value = p->to.offset;
+		if(p->to.offset > s->size)
+			s->size = p->to.offset;
 		if(p->from.scale & DUPOK)
 			s->dupok = 1;
+		if(p->from.scale & RODATA)
+			s->type = SRODATA;
 		goto loop;
 
 	case ADYNT:
@@ -788,7 +790,7 @@ loop:
 			s = lookup(literal, 0);
 			if(s->type == 0) {
 				s->type = SBSS;
-				s->value = 4;
+				s->size = 4;
 				t = prg();
 				t->as = ADATA;
 				t->line = p->line;
@@ -827,7 +829,7 @@ loop:
 			s = lookup(literal, 0);
 			if(s->type == 0) {
 				s->type = SBSS;
-				s->value = 8;
+				s->size = 8;
 				t = prg();
 				t->as = ADATA;
 				t->line = p->line;
@@ -955,7 +957,7 @@ doprof1(void)
 	q->to.offset = n;
 
 	s->type = SBSS;
-	s->value = n*4;
+	s->size = n*4;
 }
 
 void
diff --git a/src/cmd/8l/pass.c b/src/cmd/8l/pass.c
index 92a0b9334..dd2787872 100644
--- a/src/cmd/8l/pass.c
+++ b/src/cmd/8l/pass.c
@@ -55,13 +55,13 @@ dodata(void)
 			s->value = dtype;
 		if(s->type == SBSS)
 			s->type = SDATA;
-		if(s->type != SDATA && s->type != SELFDATA)
+		if(s->type != SDATA && s->type != SELFDATA && s->type != SRODATA)
 			diag("initialize non-data (%d): %s\n%P",
 				s->type, s->name, p);
 		t = p->from.offset + p->width;
-		if(t > s->value)
+		if(t > s->size)
 			diag("initialize bounds (%ld): %s\n%P",
-				s->value, s->name, p);
+				s->size, s->name, p);
 	}
 
 	/* allocate elf guys - must be segregated from real data */
@@ -72,7 +72,7 @@ dodata(void)
 			continue;
 		if(s->type != SELFDATA)
 			continue;
-		t = rnd(s->value, 4);
+		t = rnd(s->size, 4);
 		s->size = t;
 		s->value = datsize;
 		datsize += t;
@@ -87,14 +87,13 @@ dodata(void)
 		if(s->type != SDATA)
 		if(s->type != SBSS)
 			continue;
-		t = s->value;
+		t = s->size;
 		if(t == 0 && s->name[0] != '.') {
 			diag("%s: no size", s->name);
 			t = 1;
 		}
 		t = rnd(t, 4);
 		s->size = t;
-		s->value = t;
 		if(t > MINSIZ)
 			continue;
 		s->value = datsize;
@@ -110,8 +109,7 @@ dodata(void)
 				s->type = SDATA;
 			continue;
 		}
-		t = s->value;
-		s->size = t;
+		t = s->size;
 		s->value = datsize;
 		datsize += t;
 	}
@@ -154,8 +152,7 @@ dodata(void)
 			continue;
 		if(s->type != SBSS)
 			continue;
-		t = s->value;
-		s->size = t;
+		t = s->size;
 		s->value = bsssize + dynptrsize + datsize;
 		bsssize += t;
 	}
@@ -1042,10 +1039,10 @@ export(void)
 		newdata(et, off, sizeof(int32), D_EXTERN);
 		off += sizeof(int32);
 	}
-	et->value = off;
+	et->size = off;
 	if(sv == 0)
 		sv = 1;
-	str->value = sv;
+	str->size = sv;
 	exports = ne;
 	free(esyms);
 }
diff --git a/src/cmd/8l/span.c b/src/cmd/8l/span.c
index 99ba279da..3bc18adb6 100644
--- a/src/cmd/8l/span.c
+++ b/src/cmd/8l/span.c
@@ -35,8 +35,9 @@ void
 span(void)
 {
 	Prog *p, *q;
-	int32 v, c, idat;
+	int32 i, v, c, idat;
 	int m, n, again;
+	Sym *s;
 
 	xdefine("etext", STEXT, 0L);
 	idat = INITDAT;
@@ -106,6 +107,21 @@ start:
 		textsize = c;
 		n++;
 	}while(again);
+	
+	/*
+	 * allocate read-only data to the text segment.
+	 */
+	c = rnd(c, 8);
+	for(i=0; i<NHASH; i++)
+	for(s = hash[i]; s != S; s = s->link) {
+		if(s->type != SRODATA)
+			continue;
+		v = s->size;
+		while(v & 3)
+			v++;
+		s->value = c;
+		c += v;
+	}
 
 	if(INITRND) {
 		INITDAT = rnd(c+textpad, INITRND);
@@ -114,6 +130,7 @@ start:
 			goto start;
 		}
 	}
+
 	xdefine("etext", STEXT, c);
 	if(debug['v'])
 		Bprint(&bso, "etext = %lux\n", c);
@@ -208,6 +225,7 @@ asmsym(void)
 		for(s=hash[h]; s!=S; s=s->link)
 			switch(s->type) {
 			case SCONST:
+			case SRODATA:
 				if(!s->reachable)
 					continue;
 				putsymb(s->name, 'D', s->value, s->version, s->gotype);
@@ -618,6 +636,7 @@ vaddr(Adr *a)
 				ckoff(s, v);
 			case STEXT:
 			case SCONST:
+			case SRODATA:
 				if(!s->reachable)
 					sysfatal("unreachable symbol in vaddr - %s", s->name);
 				v += s->value;
diff --git a/src/cmd/gc/go.h b/src/cmd/gc/go.h
index cadaf0aaf..c39bfbbc6 100644
--- a/src/cmd/gc/go.h
+++ b/src/cmd/gc/go.h
@@ -211,6 +211,7 @@ struct	Node
 	uchar	used;
 	uchar	isddd;
 	uchar	pun;		// dont registerize variable ONAME
+	uchar	readonly;
 
 	// most nodes
 	Node*	left;
diff --git a/src/cmd/gc/subr.c b/src/cmd/gc/subr.c
index 277c25201..9c9377c4f 100644
--- a/src/cmd/gc/subr.c
+++ b/src/cmd/gc/subr.c
@@ -2600,6 +2600,7 @@ staticname(Type *t)
 	snprint(namebuf, sizeof(namebuf), "statictmp_%.4d", statuniqgen);
 	statuniqgen++;
 	n = newname(lookup(namebuf));
+//	n->readonly = 1;
 	addvar(n, t, PEXTERN);
 	return n;
 }
diff --git a/src/cmd/ld/lib.c b/src/cmd/ld/lib.c
index 808708c2c..c91705c6b 100644
--- a/src/cmd/ld/lib.c
+++ b/src/cmd/ld/lib.c
@@ -495,6 +495,7 @@ lookup(char *symb, int v)
 	s->version = v;
 	s->value = 0;
 	s->sig = 0;
+	s->size = 0;
 	hash[h] = s;
 	nsymbol++;
 	return s;
diff --git a/src/cmd/ld/macho.c b/src/cmd/ld/macho.c
index e081053c1..a14ec41e7 100644
--- a/src/cmd/ld/macho.c
+++ b/src/cmd/ld/macho.c
@@ -533,7 +533,7 @@ asmbmacho(vlong symdatva, vlong symo)
 		ml->data[0] = 4;	/* thread type */
 		ml->data[1] = 42;	/* word count */
 		ml->data[2+32] = entryvalue();	/* start pc */
-		ml->data[2+32+1] = entryvalue()>>32;
+		ml->data[2+32+1] = entryvalue()>>16>>16;	// hide >>32 for 8l
 		break;
 	case '8':
 		ml = newMachoLoad(5, 16+2);	/* unix thread */