liblink: place TEXT/GLOBL flags in p->from3 always

Before, amd64 and 386 stored the flags in p->from.scale
and arm and ppc64 stored the flags in p->reg.
Both caused special cases in printing and in handling of the
addresses.

To avoid possible conflicts with the real meaning of p->from
and to avoid storing a non-register value in a reg field,
use from3 to hold a TYPE_CONST value giving the flags.

There is still a special case for printing, because the flags
are specified without a $, and normally a TYPE_CONST prints
with a $. But that's much less special than what came before.

This allows us to remove the textflag and settextflag methods
from LinkArch. They are no longer architecture-specific.

Change-Id: I931da8e1ecd92e127cd9aa44ef5a73c42e730110
Reviewed-on: https://go-review.googlesource.com/3572
Reviewed-by: Austin Clements <austin@google.com>

11 files changed, 31 insertions, 101 deletions

diff --git a/src/liblink/asm5.c b/src/liblink/asm5.c
index 38a7399725..8723553fa4 100644
--- a/src/liblink/asm5.c
+++ b/src/liblink/asm5.c
@@ -72,7 +72,6 @@ static Optab	optab[] =
 	/* struct Optab:
 	  OPCODE,	from, prog->reg, to,		 type,size,param,flag */
 	{ ATEXT,	C_ADDR,	C_NONE,	C_TEXTSIZE, 	 0, 0, 0 },
-	{ ATEXT,	C_ADDR,	C_REG,	C_TEXTSIZE, 	 0, 0, 0 },
 
 	{ AADD,		C_REG,	C_REG,	C_REG,		 1, 4, 0 },
 	{ AADD,		C_REG,	C_NONE,	C_REG,		 1, 4, 0 },
diff --git a/src/liblink/asm9.c b/src/liblink/asm9.c
index 9101c56c51..bc3174d08f 100644
--- a/src/liblink/asm9.c
+++ b/src/liblink/asm9.c
@@ -60,13 +60,9 @@ struct	Optab
 
 static Optab	optab[] = {
 	{ ATEXT,	C_LEXT,	C_NONE, C_NONE, 	C_TEXTSIZE, 	 0, 0, 0 },
-	{ ATEXT,	C_LEXT,	C_REG, C_NONE, 	C_TEXTSIZE, 	 0, 0, 0 },
 	{ ATEXT,	C_LEXT,	C_NONE, C_LCON, 	C_TEXTSIZE, 	 0, 0, 0 },
-	{ ATEXT,	C_LEXT,	C_REG, C_LCON, 	C_TEXTSIZE, 	 0, 0, 0 },
 	{ ATEXT,	C_ADDR,	C_NONE, C_NONE, 	C_TEXTSIZE, 	 0, 0, 0 },
-	{ ATEXT,	C_ADDR,	C_REG, C_NONE, 	C_TEXTSIZE, 	 0, 0, 0 },
 	{ ATEXT,	C_ADDR,	C_NONE, C_LCON, 	C_TEXTSIZE, 	 0, 0, 0 },
-	{ ATEXT,	C_ADDR,	C_REG, C_LCON, 	C_TEXTSIZE, 	 0, 0, 0 },
 
 	/* move register */
 	{ AMOVD,	C_REG,	C_NONE, C_NONE, 	C_REG,		 1, 4, 0 },
diff --git a/src/liblink/list5.c b/src/liblink/list5.c
index d04c8c27a8..a687400b08 100644
--- a/src/liblink/list5.c
+++ b/src/liblink/list5.c
@@ -112,7 +112,7 @@ Pconv(Fmt *fp)
 		sprint(str, "%.5lld (%L)	%A	%D/%d,%D", p->pc, p->lineno, a, &p->from, p->reg, &p->to);
 	else
 	if(p->as == ATEXT)
-		sprint(str, "%.5lld (%L)	%A	%D,%d,%D", p->pc, p->lineno, a, &p->from, p->reg, &p->to);
+		sprint(str, "%.5lld (%L)	%A	%D,%lld,%D", p->pc, p->lineno, a, &p->from, p->from3.offset, &p->to);
 	else
 	if(p->reg == 0)
 		sprint(str, "%.5lld (%L)	%A%s	%D,%D", p->pc, p->lineno, a, sc, &p->from, &p->to);
diff --git a/src/liblink/list6.c b/src/liblink/list6.c
index 2cb1777ba4..c3f13e921f 100644
--- a/src/liblink/list6.c
+++ b/src/liblink/list6.c
@@ -90,9 +90,9 @@ Pconv(Fmt *fp)
 		break;
 
 	case ATEXT:
-		if(p->from.scale) {
-			sprint(str, "%.5lld (%L)	%A	%D,%d,%D",
-				p->pc, p->lineno, p->as, &p->from, p->from.scale, &p->to);
+		if(p->from3.offset) {
+			sprint(str, "%.5lld (%L)	%A	%D,%lld,%D",
+				p->pc, p->lineno, p->as, &p->from, p->from3.offset, &p->to);
 			break;
 		}
 		sprint(str, "%.5lld (%L)	%A	%D,%D",
diff --git a/src/liblink/list8.c b/src/liblink/list8.c
index 33c0791a19..c8a4ca7e8c 100644
--- a/src/liblink/list8.c
+++ b/src/liblink/list8.c
@@ -77,9 +77,9 @@ Pconv(Fmt *fp)
 		break;
 
 	case ATEXT:
-		if(p->from.scale) {
-			sprint(str, "%.5lld (%L)	%A	%D,%d,%D",
-				p->pc, p->lineno, p->as, &p->from, p->from.scale, &p->to);
+		if(p->from3.offset) {
+			sprint(str, "%.5lld (%L)	%A	%D,%lld,%D",
+				p->pc, p->lineno, p->as, &p->from, p->from3.offset, &p->to);
 			break;
 		}
 		sprint(str, "%.5lld (%L)	%A	%D,%D",
diff --git a/src/liblink/list9.c b/src/liblink/list9.c
index 149d713fe8..58eccb265d 100644
--- a/src/liblink/list9.c
+++ b/src/liblink/list9.c
@@ -95,14 +95,9 @@ Pconv(Fmt *fp)
 	str[0] = 0;
 	if(a == ADATA || a == AINIT || a == ADYNT)
 		sprint(str, "%.5lld (%L)	%A	%D/%d,%D", p->pc, p->lineno, a, &p->from, p->reg, &p->to);
-	else if(a == ATEXT) {
-		if(p->reg != 0)
-			sprint(str, "%.5lld (%L)	%A	%D,%d,%D", p->pc, p->lineno, a, &p->from, p->reg, &p->to);
-		else
-			sprint(str, "%.5lld (%L)	%A	%D,%D", p->pc, p->lineno, a, &p->from, &p->to);
-	} else if(a == AGLOBL) {
-		if(p->reg != 0)
-			sprint(str, "%.5lld (%L)	%A	%D,%d,%D", p->pc, p->lineno, a, &p->from, p->reg, &p->to);
+	else if(a == ATEXT || a == AGLOBL) {
+		if(p->from3.offset != 0)
+			sprint(str, "%.5lld (%L)	%A	%D,%lld,%D", p->pc, p->lineno, a, &p->from, p->from3.offset, &p->to);
 		else
 			sprint(str, "%.5lld (%L)	%A	%D,%D", p->pc, p->lineno, a, &p->from, &p->to);
 	} else {
diff --git a/src/liblink/obj5.c b/src/liblink/obj5.c
index 0f2e9fa4f2..8d20173912 100644
--- a/src/liblink/obj5.c
+++ b/src/liblink/obj5.c
@@ -58,18 +58,6 @@ datasize(Prog *p)
 	return p->reg;
 }
 
-static int
-textflag(Prog *p)
-{
-	return p->reg;
-}
-
-static void
-settextflag(Prog *p, int f)
-{
-	p->reg = f;
-}
-
 static void
 progedit(Link *ctxt, Prog *p)
 {
@@ -268,7 +256,7 @@ preprocess(Link *ctxt, LSym *cursym)
 	cursym->args = p->to.u.argsize;
 
 	if(ctxt->debugzerostack) {
-		if(autoffset && !(p->reg&NOSPLIT)) {
+		if(autoffset && !(p->from3.offset&NOSPLIT)) {
 			// MOVW $4(R13), R1
 			p = appendp(ctxt, p);
 			p->as = AMOVW;
@@ -421,8 +409,8 @@ preprocess(Link *ctxt, LSym *cursym)
 					break;
 			}
 
-			if(!(p->reg & NOSPLIT))
-				p = stacksplit(ctxt, p, autosize, !(cursym->text->reg&NEEDCTXT)); // emit split check
+			if(!(p->from3.offset & NOSPLIT))
+				p = stacksplit(ctxt, p, autosize, !(cursym->text->from3.offset&NEEDCTXT)); // emit split check
 			
 			// MOVW.W		R14,$-autosize(SP)
 			p = appendp(ctxt, p);
@@ -435,7 +423,7 @@ preprocess(Link *ctxt, LSym *cursym)
 			p->to.reg = REGSP;
 			p->spadj = autosize;
 			
-			if(cursym->text->reg & WRAPPER) {
+			if(cursym->text->from3.offset & WRAPPER) {
 				// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
 				//
 				//	MOVW g_panic(g), R1
@@ -1048,8 +1036,6 @@ LinkArch linkarm = {
 	.isdata = isdata,
 	.prg = prg,
 	.progedit = progedit,
-	.settextflag = settextflag,
-	.textflag = textflag,
 
 	.minlc = 4,
 	.ptrsize = 4,
diff --git a/src/liblink/obj6.c b/src/liblink/obj6.c
index 2b51061a0b..12e0606453 100644
--- a/src/liblink/obj6.c
+++ b/src/liblink/obj6.c
@@ -78,18 +78,6 @@ datasize(Prog *p)
 	return p->from.scale;
 }
 
-static int
-textflag(Prog *p)
-{
-	return p->from.scale;
-}
-
-static void
-settextflag(Prog *p, int f)
-{
-	p->from.scale = f;
-}
-
 static void nacladdr(Link*, Prog*, Addr*);
 
 static int
@@ -404,24 +392,24 @@ preprocess(Link *ctxt, LSym *cursym)
 	cursym->args = textarg;
 	cursym->locals = p->to.offset;
 
-	if(autoffset < StackSmall && !(p->from.scale & NOSPLIT)) {
+	if(autoffset < StackSmall && !(p->from3.offset & NOSPLIT)) {
 		for(q = p; q != nil; q = q->link) {
 			if(q->as == ACALL)
 				goto noleaf;
 			if((q->as == ADUFFCOPY || q->as == ADUFFZERO) && autoffset >= StackSmall - 8)
 				goto noleaf;
 		}
-		p->from.scale |= NOSPLIT;
+		p->from3.offset |= NOSPLIT;
 	noleaf:;
 	}
 
 	q = nil;
-	if(!(p->from.scale & NOSPLIT) || (p->from.scale & WRAPPER)) {
+	if(!(p->from3.offset & NOSPLIT) || (p->from3.offset & WRAPPER)) {
 		p = appendp(ctxt, p);
 		p = load_g_cx(ctxt, p); // load g into CX
 	}
-	if(!(cursym->text->from.scale & NOSPLIT))
-		p = stacksplit(ctxt, p, autoffset, textarg, !(cursym->text->from.scale&NEEDCTXT), &q); // emit split check
+	if(!(cursym->text->from3.offset & NOSPLIT))
+		p = stacksplit(ctxt, p, autoffset, textarg, !(cursym->text->from3.offset&NEEDCTXT), &q); // emit split check
 
 	if(autoffset) {
 		if(autoffset%ctxt->arch->regsize != 0)
@@ -468,7 +456,7 @@ preprocess(Link *ctxt, LSym *cursym)
 		p->to.reg = REG_BP;
 	}
 	
-	if(cursym->text->from.scale & WRAPPER) {
+	if(cursym->text->from3.offset & WRAPPER) {
 		// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
 		//
 		//	MOVQ g_panic(CX), BX
@@ -564,7 +552,7 @@ preprocess(Link *ctxt, LSym *cursym)
 		p2->pcond = p;
 	}
 
-	if(ctxt->debugzerostack && autoffset && !(cursym->text->from.scale&NOSPLIT)) {
+	if(ctxt->debugzerostack && autoffset && !(cursym->text->from3.offset&NOSPLIT)) {
 		// 6l -Z means zero the stack frame on entry.
 		// This slows down function calls but can help avoid
 		// false positives in garbage collection.
@@ -1093,8 +1081,6 @@ LinkArch linkamd64 = {
 	.isdata = isdata,
 	.prg = prg,
 	.progedit = progedit,
-	.settextflag = settextflag,
-	.textflag = textflag,
 
 	.minlc = 1,
 	.ptrsize = 8,
@@ -1127,8 +1113,6 @@ LinkArch linkamd64p32 = {
 	.isdata = isdata,
 	.prg = prg,
 	.progedit = progedit,
-	.settextflag = settextflag,
-	.textflag = textflag,
 
 	.minlc = 1,
 	.ptrsize = 4,
diff --git a/src/liblink/obj8.c b/src/liblink/obj8.c
index cceeeb1b87..16b0e07eac 100644
--- a/src/liblink/obj8.c
+++ b/src/liblink/obj8.c
@@ -69,18 +69,6 @@ datasize(Prog *p)
 }
 
 static int
-textflag(Prog *p)
-{
-	return p->from.scale;
-}
-
-static void
-settextflag(Prog *p, int f)
-{
-	p->from.scale = f;
-}
-
-static int
 canuselocaltls(Link *ctxt)
 {
 	switch(ctxt->headtype) {
@@ -302,12 +290,12 @@ preprocess(Link *ctxt, LSym *cursym)
 
 	q = nil;
 
-	if(!(p->from.scale & NOSPLIT) || (p->from.scale & WRAPPER)) {
+	if(!(p->from3.offset & NOSPLIT) || (p->from3.offset & WRAPPER)) {
 		p = appendp(ctxt, p);
 		p = load_g_cx(ctxt, p); // load g into CX
 	}
-	if(!(cursym->text->from.scale & NOSPLIT))
-		p = stacksplit(ctxt, p, autoffset, !(cursym->text->from.scale&NEEDCTXT), &q); // emit split check
+	if(!(cursym->text->from3.offset & NOSPLIT))
+		p = stacksplit(ctxt, p, autoffset, !(cursym->text->from3.offset&NEEDCTXT), &q); // emit split check
 
 	if(autoffset) {
 		p = appendp(ctxt, p);
@@ -330,7 +318,7 @@ preprocess(Link *ctxt, LSym *cursym)
 		q->pcond = p;
 	deltasp = autoffset;
 	
-	if(cursym->text->from.scale & WRAPPER) {
+	if(cursym->text->from3.offset & WRAPPER) {
 		// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
 		//
 		//	MOVL g_panic(CX), BX
@@ -401,7 +389,7 @@ preprocess(Link *ctxt, LSym *cursym)
 		p2->pcond = p;
 	}
 	
-	if(ctxt->debugzerostack && autoffset && !(cursym->text->from.scale&NOSPLIT)) {
+	if(ctxt->debugzerostack && autoffset && !(cursym->text->from3.offset&NOSPLIT)) {
 		// 8l -Z means zero the stack frame on entry.
 		// This slows down function calls but can help avoid
 		// false positives in garbage collection.
@@ -894,8 +882,6 @@ LinkArch link386 = {
 	.isdata = isdata,
 	.prg = prg,
 	.progedit = progedit,
-	.settextflag = settextflag,
-	.textflag = textflag,
 
 	.minlc = 1,
 	.ptrsize = 4,
diff --git a/src/liblink/obj9.c b/src/liblink/obj9.c
index 6f7652f5f8..60fa1d66e1 100644
--- a/src/liblink/obj9.c
+++ b/src/liblink/obj9.c
@@ -57,18 +57,6 @@ datasize(Prog *p)
 	return p->reg;
 }
 
-static int
-textflag(Prog *p)
-{
-	return p->reg;
-}
-
-static void
-settextflag(Prog *p, int f)
-{
-	p->reg = f;
-}
-
 static void
 progedit(Link *ctxt, Prog *p)
 {
@@ -367,8 +355,8 @@ preprocess(Link *ctxt, LSym *cursym)
 					autosize += 4;
 			p->to.offset = autosize-8;
 
-			if(!(p->reg & NOSPLIT))
-				p = stacksplit(ctxt, p, autosize, !(cursym->text->reg&NEEDCTXT)); // emit split check
+			if(!(p->from3.offset & NOSPLIT))
+				p = stacksplit(ctxt, p, autosize, !(cursym->text->from3.offset&NEEDCTXT)); // emit split check
 
 			q = p;
 			if(autosize) {
@@ -420,7 +408,7 @@ preprocess(Link *ctxt, LSym *cursym)
 			if(q->as == AMOVDU)
 				q->spadj = -aoffset;
 
-			if(cursym->text->reg & WRAPPER) {
+			if(cursym->text->from3.offset & WRAPPER) {
 				// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
 				//
 				//	MOVD g_panic(g), R3
@@ -970,8 +958,6 @@ LinkArch linkppc64 = {
 	.isdata = isdata,
 	.prg = prg,
 	.progedit = progedit,
-	.settextflag = settextflag,
-	.textflag = textflag,
 
 	.minlc = 4,
 	.ptrsize = 8,
@@ -1004,8 +990,6 @@ LinkArch linkppc64le = {
 	.isdata = isdata,
 	.prg = prg,
 	.progedit = progedit,
-	.settextflag = settextflag,
-	.textflag = textflag,
 
 	.minlc = 4,
 	.ptrsize = 8,
diff --git a/src/liblink/objfile.c b/src/liblink/objfile.c
index bdd63ccb64..79a88db0bf 100644
--- a/src/liblink/objfile.c
+++ b/src/liblink/objfile.c
@@ -189,7 +189,7 @@ writeobj(Link *ctxt, Biobuf *b)
 				s->size = p->to.offset;
 				if(s->type == 0 || s->type == SXREF)
 					s->type = SBSS;
-				flag = ctxt->arch->textflag(p);
+				flag = p->from3.offset;
 				if(flag & DUPOK)
 					s->dupok = 1;
 				if(flag & RODATA)
@@ -222,7 +222,7 @@ writeobj(Link *ctxt, Biobuf *b)
 				else
 					etext->next = s;
 				etext = s;
-				flag = ctxt->arch->textflag(p);
+				flag = p->from3.offset;
 				if(flag & DUPOK)
 					s->dupok = 1;
 				if(flag & NOSPLIT)