liblink: adjust format verbs to avoid collisions

The %S and %N format verbs are used by cmd/gc to
represent Sym and Node structures, respectively.

In liblink, these two verbs are used only by the %D
format routine and never referenced externally.

This change will allow us to delete the duplicated
code for the %A, %D, %P, and %R format routines in
both the compiler and linker.

R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/49720043

src/liblink/list5.c

@@ -41,18 +41,18 @@ enum
 
 static int	Aconv(Fmt *fp);
 static int	Dconv(Fmt *fp);
-static int	Nconv(Fmt *fp);
+static int	Mconv(Fmt *fp);
 static int	Pconv(Fmt *fp);
 static int	Rconv(Fmt *fp);
-static int	Sconv(Fmt *fp);
+static int	DSconv(Fmt *fp);
 
 void
 listinit5(void)
 {
 	fmtinstall('A', Aconv);
 	fmtinstall('P', Pconv);
-	fmtinstall('S', Sconv);
-	fmtinstall('N', Nconv);
+	fmtinstall('$', DSconv);
+	fmtinstall('M', Mconv);
 	fmtinstall('D', Dconv);
 	fmtinstall('R', Rconv);
 }
@@ -139,14 +139,14 @@ Dconv(Fmt *fp)
 	case D_NONE:
 		str[0] = 0;
 		if(a->name != D_NONE || a->reg != NREG || a->sym != nil)
-			sprint(str, "%N(R%d)(NONE)", a, a->reg);
+			sprint(str, "%M(R%d)(NONE)", a, a->reg);
 		break;
 
 	case D_CONST:
 		if(a->reg != NREG)
-			sprint(str, "$%N(R%d)", a, a->reg);
+			sprint(str, "$%M(R%d)", a, a->reg);
 		else
-			sprint(str, "$%N", a);
+			sprint(str, "$%M", a);
 		break;
 
 	case D_CONST2:
@@ -166,27 +166,27 @@ Dconv(Fmt *fp)
 
 	case D_OREG:
 		if(a->reg != NREG)
-			sprint(str, "%N(R%d)", a, a->reg);
+			sprint(str, "%M(R%d)", a, a->reg);
 		else
-			sprint(str, "%N", a);
+			sprint(str, "%M", a);
 		break;
 
 	case D_REG:
 		sprint(str, "R%d", a->reg);
 		if(a->name != D_NONE || a->sym != nil)
-			sprint(str, "%N(R%d)(REG)", a, a->reg);
+			sprint(str, "%M(R%d)(REG)", a, a->reg);
 		break;
 
 	case D_FREG:
 		sprint(str, "F%d", a->reg);
 		if(a->name != D_NONE || a->sym != nil)
-			sprint(str, "%N(R%d)(REG)", a, a->reg);
+			sprint(str, "%M(R%d)(REG)", a, a->reg);
 		break;
 
 	case D_PSR:
 		sprint(str, "PSR");
 		if(a->name != D_NONE || a->sym != nil)
-			sprint(str, "%N(PSR)(REG)", a);
+			sprint(str, "%M(PSR)(REG)", a);
 		break;
 
 	case D_BRANCH:
@@ -203,7 +203,7 @@ Dconv(Fmt *fp)
 		break;
 
 	case D_SCONST:
-		sprint(str, "$\"%S\"", a->u.sval);
+		sprint(str, "$\"%$\"", a->u.sval);
 		break;
 	}
 	return fmtstrcpy(fp, str);
@@ -242,7 +242,7 @@ Rconv(Fmt *fp)
 }
 
 static int
-Sconv(Fmt *fp)
+DSconv(Fmt *fp)
 {
 	int i, c;
 	char str[STRINGSZ], *p, *a;
@@ -289,7 +289,7 @@ Sconv(Fmt *fp)
 }
 
 static int
-Nconv(Fmt *fp)
+Mconv(Fmt *fp)
 {
 	char str[STRINGSZ];
 	Addr *a;

src/liblink/list6.c

@@ -34,11 +34,24 @@
 #include <link.h>
 #include "../cmd/6l/6.out.h"
 
+//
+// Format conversions
+//	%A int		Opcodes (instruction mnemonics)
+//
+//	%D Addr*	Addresses (instruction operands)
+//		Flags: "%lD": seperate the high and low words of a constant by "-"
+//
+//	%P Prog*	Instructions
+//
+//	%R int		Registers
+//
+//	%$ char*	String constant addresses (for internal use only)
+
 static int	Aconv(Fmt *fp);
 static int	Dconv(Fmt *fp);
 static int	Pconv(Fmt *fp);
 static int	Rconv(Fmt *fp);
-static int	Sconv(Fmt *fp);
+static int	DSconv(Fmt *fp);
 
 enum
 {
@@ -50,7 +63,7 @@ listinit6(void)
 {
 	fmtinstall('A', Aconv);
 	fmtinstall('P', Pconv);
-	fmtinstall('S', Sconv);
+	fmtinstall('$', DSconv);
 	fmtinstall('D', Dconv);
 	fmtinstall('R', Rconv);
 }
@@ -174,7 +187,7 @@ Dconv(Fmt *fp)
 		break;
 
 	case D_SCONST:
-		sprint(str, "$\"%S\"", a->u.sval);
+		sprint(str, "$\"%$\"", a->u.sval);
 		break;
 
 	case D_ADDR:
@@ -337,7 +350,7 @@ Rconv(Fmt *fp)
 }
 
 static int
-Sconv(Fmt *fp)
+DSconv(Fmt *fp)
 {
 	int i, c;
 	char str[STRINGSZ], *p, *a;

src/liblink/list8.c

@@ -38,7 +38,7 @@ static int	Aconv(Fmt *fp);
 static int	Dconv(Fmt *fp);
 static int	Pconv(Fmt *fp);
 static int	Rconv(Fmt *fp);
-static int	Sconv(Fmt *fp);
+static int	DSconv(Fmt *fp);
 
 enum
 {
@@ -50,7 +50,7 @@ listinit8(void)
 {
 	fmtinstall('A', Aconv);
 	fmtinstall('P', Pconv);
-	fmtinstall('S', Sconv);
+	fmtinstall('$', DSconv);
 	fmtinstall('D', Dconv);
 	fmtinstall('R', Rconv);
 }
@@ -181,7 +181,7 @@ Dconv(Fmt *fp)
 		break;
 
 	case D_SCONST:
-		sprint(str, "$\"%S\"", a->u.sval);
+		sprint(str, "$\"%$\"", a->u.sval);
 		break;
 
 	case D_ADDR:
@@ -298,7 +298,7 @@ Rconv(Fmt *fp)
 }
 
 static int
-Sconv(Fmt *fp)
+DSconv(Fmt *fp)
 {
 	int i, c;
 	char str[STRINGSZ], *p, *a;