6l/8l: emit DWARF frame info.

R=rsc, ken2, r
CC=golang-dev
https://golang.org/cl/2151044

src/cmd/6l/l.h

@@ -95,6 +95,7 @@ struct	Prog
 	Prog*	dlink;
 	Prog*	pcond;	/* work on this */
 	vlong	pc;
+	int32	spadj;
 	int32	line;
 	short	as;
 	char	ft;	/* oclass cache */
@@ -102,7 +103,7 @@ struct	Prog
 	uchar	mark;	/* work on these */
 	uchar	back;
 
-	char	width;		/* fake for DATA */
+	char	width;	/* fake for DATA */
 	char	mode;	/* 16, 32, or 64 */
 };
 struct	Auto
@@ -397,7 +398,7 @@ void	buildop(void);
 void	cflush(void);
 void	ckoff(Sym*, int32);
 Prog*	copyp(Prog*);
-vlong   cpos(void);
+vlong	cpos(void);
 double	cputime(void);
 void	datblk(int32, int32);
 void	deadcode(void);
@@ -463,3 +464,9 @@ uint32	machheadr(void);
 #pragma	varargck	type	"R"	int
 #pragma	varargck	type	"A"	int
 #pragma	varargck	argpos	diag 1
+
+/* Used by ../ld/dwarf.c */
+enum
+{
+	DWARFREGSP = 7
+};

src/cmd/6l/pass.c

@@ -692,7 +692,7 @@ dostkoff(void)
 					p->from.type = D_INDIR+D_GS;
 				p->from.offset = tlsoffset+0;
 				p->to.type = D_CX;
-				
+
 				if(debug['K']) {
 					// 6l -K means check not only for stack
 					// overflow but stack underflow.
@@ -843,6 +843,7 @@ dostkoff(void)
 				p->as = AADJSP;
 				p->from.type = D_CONST;
 				p->from.offset = autoffset;
+				p->spadj = autoffset;
 				if(q != P)
 					q->pcond = p;
 			}
@@ -903,26 +904,32 @@ dostkoff(void)
 		case APUSHL:
 		case APUSHFL:
 			deltasp += 4;
+			p->spadj = 4;
 			continue;
 		case APUSHQ:
 		case APUSHFQ:
 			deltasp += 8;
+			p->spadj = 8;
 			continue;
 		case APUSHW:
 		case APUSHFW:
 			deltasp += 2;
+			p->spadj = 2;
 			continue;
 		case APOPL:
 		case APOPFL:
 			deltasp -= 4;
+			p->spadj = -4;
 			continue;
 		case APOPQ:
 		case APOPFQ:
 			deltasp -= 8;
+			p->spadj = -8;
 			continue;
 		case APOPW:
 		case APOPFW:
 			deltasp -= 2;
+			p->spadj = -2;
 			continue;
 		case ARET:
 			break;
@@ -937,7 +944,7 @@ dostkoff(void)
 			p->as = AADJSP;
 			p->from.type = D_CONST;
 			p->from.offset = -autoffset;
-
+			p->spadj = -autoffset;
 			p = appendp(p);
 			p->as = ARET;
 		}
@@ -954,6 +961,7 @@ dostkoff(void)
 		q->from = zprg.from;
 		q->from.type = D_CONST;
 		q->from.offset = -autoffset;
+		q->spadj = -autoffset;
 		q->to = zprg.to;
 		continue;
 	}

src/cmd/8l/l.h

@@ -95,6 +95,7 @@ struct	Prog
 	Prog*	dlink;
 	Prog*	pcond;	/* work on this */
 	int32	pc;
+	int32	spadj;
 	int32	line;
 	short	as;
 	char	width;		/* fake for DATA */
@@ -346,7 +347,7 @@ Prog*	brloop(Prog*);
 void	cflush(void);
 void	ckoff(Sym*, int32);
 Prog*	copyp(Prog*);
-vlong   cpos(void);
+vlong	cpos(void);
 double	cputime(void);
 void	datblk(int32, int32, int32);
 void	diag(char*, ...);
@@ -412,3 +413,9 @@ void	deadcode(void);
 #pragma	varargck	type	"P"	Prog*
 #pragma	varargck	type	"R"	int
 #pragma	varargck	type	"A"	int
+
+/* Used by ../ld/dwarf.c */
+enum
+{
+	DWARFREGSP = 4
+};

src/cmd/8l/pass.c

@@ -392,10 +392,10 @@ patch(void)
 	for(p = firstp; p != P; p = p->link) {
 		if(HEADTYPE == 10) {	// Windows
 			// Convert
-			//   op   n(GS), reg
+			//   op	  n(GS), reg
 			// to
 			//   MOVL 0x2C(FS), reg
-			//   op   n(reg), reg
+			//   op	  n(reg), reg
 			// The purpose of this patch is to fix some accesses
 			// to extern register variables (TLS) on Windows, as
 			// a different method is used to access them.
@@ -770,6 +770,7 @@ dostkoff(void)
 				p->as = AADJSP;
 				p->from.type = D_CONST;
 				p->from.offset = autoffset;
+				p->spadj = autoffset;
 				if(q != P)
 					q->pcond = p;
 			}
@@ -792,18 +793,22 @@ dostkoff(void)
 		case APUSHL:
 		case APUSHFL:
 			deltasp += 4;
+			p->spadj = 4;
 			continue;
 		case APUSHW:
 		case APUSHFW:
 			deltasp += 2;
+			p->spadj = 2;
 			continue;
 		case APOPL:
 		case APOPFL:
 			deltasp -= 4;
+			p->spadj = -4;
 			continue;
 		case APOPW:
 		case APOPFW:
 			deltasp -= 2;
+			p->spadj = -2;
 			continue;
 		case ARET:
 			break;
@@ -822,6 +827,7 @@ dostkoff(void)
 			q->as = AADJSP;
 			q->from.type = D_CONST;
 			q->from.offset = -autoffset;
+			p->spadj = -autoffset;
 		}
 		continue;
 
@@ -836,6 +842,7 @@ dostkoff(void)
 		q->from = zprg.from;
 		q->from.type = D_CONST;
 		q->from.offset = -autoffset;
+		p->spadj = -autoffset;
 		q->to = zprg.to;
 		continue;
 	}

src/cmd/ld/dwarf_defs.h

@@ -452,3 +452,39 @@ enum
 	DW_MACINFO_end_file = 0x04,
 	DW_MACINFO_vendor_ext = 0xff,
 };
+
+// Table 40.
+enum
+{					// operand,...
+	DW_CFA_nop = 0x00,
+	DW_CFA_set_loc = 0x01,		// address
+	DW_CFA_advance_loc1 = 0x02,	// 1-byte delta
+	DW_CFA_advance_loc2 = 0x03,	// 2-byte delta
+	DW_CFA_advance_loc4 = 0x04,	// 4-byte delta
+	DW_CFA_offset_extended = 0x05,	// ULEB128 register, ULEB128 offset
+	DW_CFA_restore_extended = 0x06, // ULEB128 register
+	DW_CFA_undefined = 0x07,	// ULEB128 register
+	DW_CFA_same_value = 0x08,	// ULEB128 register
+	DW_CFA_register = 0x09,		// ULEB128 register, ULEB128 register
+	DW_CFA_remember_state = 0x0a,
+	DW_CFA_restore_state = 0x0b,
+	DW_CFA_def_cfa = 0x0c,		// ULEB128 register, ULEB128 offset
+	DW_CFA_def_cfa_register = 0x0d,	// ULEB128 register
+	DW_CFA_def_cfa_offset = 0x0e,	// ULEB128 offset
+	DW_CFA_def_cfa_expression = 0x0f, // BLOCK
+	DW_CFA_expression = 0x10,	// ULEB128 register, BLOCK
+	DW_CFA_offset_extended_sf = 0x11, // ULEB128 register, SLEB128 offset
+	DW_CFA_def_cfa_sf = 0x12,	// ULEB128 register, SLEB128 offset
+	DW_CFA_def_cfa_offset_sf = 0x13, // SLEB128 offset
+	DW_CFA_val_offset = 0x14,	// ULEB128, ULEB128
+	DW_CFA_val_offset_sf = 0x15,	// ULEB128, SLEB128
+	DW_CFA_val_expression = 0x16,	// ULEB128, BLOCK
+
+	DW_CFA_lo_user = 0x1c,
+	DW_CFA_hi_user = 0x3f,
+
+	// Opcodes that take an addend operand.
+	DW_CFA_advance_loc = 0x1<<6, // +delta
+	DW_CFA_offset	   = 0x2<<6, // +register (ULEB128 offset)
+	DW_CFA_restore	   = 0x3<<6, // +register
+};