[568]a: precise linenumbers for statements.

R=rsc, ken2, r, rsc1
CC=golang-dev
https://golang.org/cl/2297042

src/cmd/5a/a.h

 // Inferno utils/5a/a.h
 // http://code.google.com/p/inferno-os/source/browse/utils/5a/a.h
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -148,6 +148,7 @@ EXTERN	int	pass;
 EXTERN	char*	pathname;
 EXTERN	int32	pc;
 EXTERN	int	peekc;
+EXTERN	int32	stmtline;
 EXTERN	int	sym;
 EXTERN	char*	symb;
 EXTERN	int	thechar;
@@ -157,7 +158,7 @@ EXTERN	Biobuf	obuf;
 
 void*	alloc(int32);
 void*	allocn(void*, int32, int32);
-void    ensuresymb(int32);
+void	ensuresymb(int32);
 void	errorexit(void);
 void	pushio(void);
 void	newio(void);

src/cmd/5a/a.y

 // Inferno utils/5a/a.y
 // http://code.google.com/p/inferno-os/source/browse/utils/5a/a.y
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -63,7 +63,11 @@
 %type	<gen>	imm ximm name oreg ireg nireg ioreg imsr
 %%
 prog:
-|	prog line
+|	prog
+	{
+		stmtline = lineno;
+	}
+	line
 
 line:
 	LLAB ':'

src/cmd/5a/lex.c

 // Inferno utils/5a/lex.c
 // http://code.google.com/p/inferno-os/source/browse/utils/5a/lex.c
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -658,10 +658,10 @@ jackpot:
 	Bputc(&obuf, a);
 	Bputc(&obuf, scond);
 	Bputc(&obuf, reg);
-	Bputc(&obuf, lineno);
-	Bputc(&obuf, lineno>>8);
-	Bputc(&obuf, lineno>>16);
-	Bputc(&obuf, lineno>>24);
+	Bputc(&obuf, stmtline);
+	Bputc(&obuf, stmtline>>8);
+	Bputc(&obuf, stmtline>>16);
+	Bputc(&obuf, stmtline>>24);
 	zaddr(g1, sf);
 	zaddr(g2, st);
 

src/cmd/6a/a.h

 // Inferno utils/6a/a.h
 // http://code.google.com/p/inferno-os/source/browse/utils/6a/a.h
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -50,7 +50,7 @@ typedef	struct	Ref	Ref;
 typedef	struct	Gen	Gen;
 typedef	struct	Io	Io;
 typedef	struct	Hist	Hist;
-typedef	struct	Gen2 	Gen2;
+typedef	struct	Gen2	Gen2;
 
 #define	MAXALIGN	7
 #define	FPCHIP		1
@@ -161,6 +161,7 @@ EXTERN	int	pass;
 EXTERN	char*	pathname;
 EXTERN	int32	pc;
 EXTERN	int	peekc;
+EXTERN	int32	stmtline;
 EXTERN	int	sym;
 EXTERN	char*	symb;
 EXTERN	int	thechar;
@@ -168,9 +169,9 @@ EXTERN	char*	thestring;
 EXTERN	int32	thunk;
 EXTERN	Biobuf	obuf;
 
-void*   alloc(int32);
+void*	alloc(int32);
 void*	allocn(void*, int32, int32);
-void    ensuresymb(int32);
+void	ensuresymb(int32);
 void	errorexit(void);
 void	pushio(void);
 void	newio(void);

src/cmd/6a/a.y

 // Inferno utils/6a/a.y
 // http://code.google.com/p/inferno-os/source/browse/utils/6a/a.y
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -60,7 +60,11 @@
 %type	<gen2>	spec1 spec2 spec3 spec4 spec5 spec6 spec7 spec8 spec9
 %%
 prog:
-|	prog line
+|	prog 
+	{
+		stmtline = lineno;
+	}
+	line
 
 line:
 	LLAB ':'

src/cmd/6a/lex.c

 // Inferno utils/6a/lex.c
 // http://code.google.com/p/inferno-os/source/browse/utils/6a/lex.c
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -1260,10 +1260,10 @@ jackpot:
 	}
 	Bputc(&obuf, a);
 	Bputc(&obuf, a>>8);
-	Bputc(&obuf, lineno);
-	Bputc(&obuf, lineno>>8);
-	Bputc(&obuf, lineno>>16);
-	Bputc(&obuf, lineno>>24);
+	Bputc(&obuf, stmtline);
+	Bputc(&obuf, stmtline>>8);
+	Bputc(&obuf, stmtline>>16);
+	Bputc(&obuf, stmtline>>24);
 	zaddr(&g2->from, sf);
 	zaddr(&g2->to, st);
 

src/cmd/8a/a.h

 // Inferno utils/8a/a.h
 // http://code.google.com/p/inferno-os/source/browse/utils/8a/a.h
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -50,7 +50,7 @@ typedef	struct	Ref	Ref;
 typedef	struct	Gen	Gen;
 typedef	struct	Io	Io;
 typedef	struct	Hist	Hist;
-typedef	struct	Gen2 	Gen2;
+typedef	struct	Gen2	Gen2;
 
 #define	MAXALIGN	7
 #define	FPCHIP		1
@@ -162,6 +162,7 @@ EXTERN	int	pass;
 EXTERN	char*	pathname;
 EXTERN	int32	pc;
 EXTERN	int	peekc;
+EXTERN	int32	stmtline;
 EXTERN	int	sym;
 EXTERN	char*	symb;
 EXTERN	int	thechar;
@@ -169,9 +170,9 @@ EXTERN	char*	thestring;
 EXTERN	int32	thunk;
 EXTERN	Biobuf	obuf;
 
-void*   alloc(int32);
+void*	alloc(int32);
 void*	allocn(void*, int32, int32);
-void    ensuresymb(int32);
+void	ensuresymb(int32);
 void	errorexit(void);
 void	pushio(void);
 void	newio(void);

src/cmd/8a/a.y

 // Inferno utils/8a/a.y
 // http://code.google.com/p/inferno-os/source/browse/utils/8a/a.y
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -64,7 +64,11 @@
 %type	<gen2>	spec1 spec2 spec3 spec4 spec5 spec6 spec7 spec8
 %%
 prog:
-|	prog line
+|	prog
+	{
+		stmtline = lineno;
+	}
+	line
 
 line:
 	LLAB ':'

src/cmd/8a/lex.c

 // Inferno utils/8a/lex.c
 // http://code.google.com/p/inferno-os/source/browse/utils/8a/lex.c
 //
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Copyright © 1994-1999 Lucent Technologies Inc.	All rights reserved.
 //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
 //	Portions Copyright © 1997-1999 Vita Nuova Limited
 //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
@@ -925,10 +925,10 @@ jackpot:
 	}
 	Bputc(&obuf, a);
 	Bputc(&obuf, a>>8);
-	Bputc(&obuf, lineno);
-	Bputc(&obuf, lineno>>8);
-	Bputc(&obuf, lineno>>16);
-	Bputc(&obuf, lineno>>24);
+	Bputc(&obuf, stmtline);
+	Bputc(&obuf, stmtline>>8);
+	Bputc(&obuf, stmtline>>16);
+	Bputc(&obuf, stmtline>>24);
 	zaddr(&g2->from, sf);
 	zaddr(&g2->to, st);
 

src/cmd/ld/dwarf.c

@@ -436,7 +436,7 @@ decodez(char *s)
  * The line history itself
  */
 
-static char **histfile;	   // [0] holds the empty string.
+static char **histfile;	   // [0] holds "<eof>", DW_LNS_set_file arguments must be > 0.
 static int  histfilesize;
 static int  histfilecap;
 
@@ -445,7 +445,7 @@ clearhistfile(void)
 {
 	int i;
 
-	// [0] holds the empty string.
+	// [0] holds "<eof>"
 	for (i = 1; i < histfilesize; i++)
 		free(histfile[i]);
 	histfilesize = 0;
@@ -756,12 +756,17 @@ writelines(void)
 		newattr(dwinfo->child, DW_AT_low_pc, DW_CLS_ADDRESS, p->pc, 0);
 
 		for(q = p; q != P && (q == p || q->as != ATEXT); q = q->link) {
-                        epc = q->pc;
+			epc = q->pc;
 			lh = searchhist(q->line);
 			if (lh == nil) {
 				diag("corrupt history or bad absolute line: %P", q);
 				continue;
 			}
+			if (lh->file < 1) {  // 0 is the past-EOF entry.
+				diag("instruction with linenumber past EOF in %s: %P", unitname, q);
+				continue;
+			}
+
 			lline = lh->line + q->line - lh->absline;
 			if (debug['v'] > 1)
 				print("%6llux %s[%lld] %P\n", q->pc, histfile[lh->file], lline, q);