Imported Upstream version 1upstream/1

13 files changed, 320 insertions, 161 deletions

diff --git a/src/cmd/8g/Makefile b/src/cmd/8g/Makefile
index b459782a3..3f528d751 100644
--- a/src/cmd/8g/Makefile
+++ b/src/cmd/8g/Makefile
@@ -1,36 +1,5 @@
-# Copyright 2009 The Go Authors. All rights reserved.
+# Copyright 2012 The Go Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
 
-include ../../Make.inc
-O:=$(HOST_O)
-
-TARG=8g
-
-HFILES=\
-	../gc/go.h\
-	../8l/8.out.h\
-	gg.h\
-	opt.h\
-
-OFILES=\
-	../8l/enam.$O\
-	cgen.$O\
-	cgen64.$O\
-	cplx.$O\
-	galign.$O\
-	ggen.$O\
-	gobj.$O\
-	gsubr.$O\
-	list.$O\
-	peep.$O\
-	pgen.$O\
-	reg.$O\
-
-LIB=\
-	../gc/gc.a\
-
-include ../../Make.ccmd
-
-%.$O: ../gc/%.c
-	$(HOST_CC) $(HOST_CFLAGS) -c -I. -o $@ ../gc/$*.c
+include ../../Make.dist
diff --git a/src/cmd/8g/cgen.c b/src/cmd/8g/cgen.c
index b316e6e34..48619ac73 100644
--- a/src/cmd/8g/cgen.c
+++ b/src/cmd/8g/cgen.c
@@ -5,6 +5,8 @@
 // TODO(rsc):
 //	assume CLD?
 
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
 
 void
@@ -96,6 +98,9 @@ cgen(Node *n, Node *res)
 		if(isslice(n->left->type))
 			n->addable = n->left->addable;
 		break;
+	case OITAB:
+		n->addable = n->left->addable;
+		break;
 	}
 
 	// if both are addressable, move
@@ -250,6 +255,13 @@ cgen(Node *n, Node *res)
 		regfree(&n1);
 		break;
 
+	case OITAB:
+		igen(nl, &n1, res);
+		n1.type = ptrto(types[TUINTPTR]);
+		gmove(&n1, res);
+		regfree(&n1);
+		break;
+
 	case OLEN:
 		if(istype(nl->type, TMAP) || istype(nl->type, TCHAN)) {
 			// map has len in the first 32-bit word.
@@ -680,7 +692,6 @@ agen(Node *n, Node *res)
 		break;
 
 	case ODOT:
-		t = nl->type;
 		agen(nl, res);
 		if(n->xoffset != 0) {
 			nodconst(&n1, types[tptr], n->xoffset);
@@ -786,6 +797,7 @@ bgen(Node *n, int true, Prog *to)
 	int et, a;
 	Node *nl, *nr, *r;
 	Node n1, n2, tmp, t1, t2, ax;
+	NodeList *ll;
 	Prog *p1, *p2;
 
 	if(debug['g']) {
@@ -798,9 +810,6 @@ bgen(Node *n, int true, Prog *to)
 	if(n->ninit != nil)
 		genlist(n->ninit);
 
-	nl = n->left;
-	nr = n->right;
-
 	if(n->type == T) {
 		convlit(&n, types[TBOOL]);
 		if(n->type == T)
@@ -813,7 +822,6 @@ bgen(Node *n, int true, Prog *to)
 		patch(gins(AEND, N, N), to);
 		return;
 	}
-	nl = N;
 	nr = N;
 
 	switch(n->op) {
@@ -905,7 +913,10 @@ bgen(Node *n, int true, Prog *to)
 				p1 = gbranch(AJMP, T);
 				p2 = gbranch(AJMP, T);
 				patch(p1, pc);
+				ll = n->ninit;  // avoid re-genning ninit
+				n->ninit = nil;
 				bgen(n, 1, p2);
+				n->ninit = ll;
 				patch(gbranch(AJMP, T), to);
 				patch(p2, pc);
 				break;
@@ -1129,24 +1140,29 @@ stkof(Node *n)
  *	memmove(&res, &n, w);
  */
 void
-sgen(Node *n, Node *res, int32 w)
+sgen(Node *n, Node *res, int64 w)
 {
 	Node dst, src, tdst, tsrc;
 	int32 c, q, odst, osrc;
 
 	if(debug['g']) {
-		print("\nsgen w=%d\n", w);
+		print("\nsgen w=%lld\n", w);
 		dump("r", n);
 		dump("res", res);
 	}
-	if(w == 0)
-		return;
-	if(n->ullman >= UINF && res->ullman >= UINF) {
+	if(n->ullman >= UINF && res->ullman >= UINF)
 		fatal("sgen UINF");
-	}
 
-	if(w < 0)
-		fatal("sgen copy %d", w);
+	if(w < 0 || (int32)w != w)
+		fatal("sgen copy %lld", w);
+
+	if(w == 0) {
+		// evaluate side effects only.
+		tempname(&tdst, types[tptr]);
+		agen(res, &tdst);
+		agen(n, &tdst);
+		return;
+	}
 
 	// offset on the stack
 	osrc = stkof(n);
diff --git a/src/cmd/8g/cgen64.c b/src/cmd/8g/cgen64.c
index ba99cec74..8e568a0f9 100644
--- a/src/cmd/8g/cgen64.c
+++ b/src/cmd/8g/cgen64.c
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
 
 /*
diff --git a/src/cmd/8g/doc.go b/src/cmd/8g/doc.go
index 2d9ff9a42..6d678eac8 100644
--- a/src/cmd/8g/doc.go
+++ b/src/cmd/8g/doc.go
@@ -9,7 +9,5 @@ The $GOARCH for these tools is 386.
 
 It reads .go files and outputs .8 files. The flags are documented in ../gc/doc.go.
 
-There is no instruction optimizer, so the -N flag is a no-op.
-
 */
 package documentation
diff --git a/src/cmd/8g/galign.c b/src/cmd/8g/galign.c
index 7734603c4..4526a2efb 100644
--- a/src/cmd/8g/galign.c
+++ b/src/cmd/8g/galign.c
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
 
 int	thechar	= '8';
diff --git a/src/cmd/8g/gg.h b/src/cmd/8g/gg.h
index 9f7a66a29..0a4f0ad2d 100644
--- a/src/cmd/8g/gg.h
+++ b/src/cmd/8g/gg.h
@@ -2,16 +2,13 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#include <u.h>
-#include <libc.h>
-
-#include "../gc/go.h"
-#include "../8l/8.out.h"
-
 #ifndef	EXTERN
 #define	EXTERN	extern
 #endif
 
+#include "../gc/go.h"
+#include "../8l/8.out.h"
+
 typedef	struct	Addr	Addr;
 
 struct	Addr
@@ -46,6 +43,8 @@ struct	Prog
 	void*	reg;		// pointer to containing Reg struct
 };
 
+#define TEXTFLAG from.scale
+
 // foptoas flags
 enum
 {
@@ -54,15 +53,12 @@ enum
 	Fpop2 = 1<<2,
 };
 
-EXTERN	Biobuf*	bout;
 EXTERN	int32	dynloc;
 EXTERN	uchar	reg[D_NONE];
 EXTERN	int32	pcloc;		// instruction counter
 EXTERN	Strlit	emptystring;
 extern	char*	anames[];
-EXTERN	Hist*	hist;
 EXTERN	Prog	zprog;
-EXTERN	Node*	curfn;
 EXTERN	Node*	newproc;
 EXTERN	Node*	deferproc;
 EXTERN	Node*	deferreturn;
@@ -103,7 +99,7 @@ void	agenr(Node *n, Node *a, Node *res);
 void	igen(Node*, Node*, Node*);
 vlong	fieldoffset(Type*, Node*);
 void	bgen(Node*, int, Prog*);
-void	sgen(Node*, Node*, int32);
+void	sgen(Node*, Node*, int64);
 void	gmove(Node*, Node*);
 Prog*	gins(int, Node*, Node*);
 int	samaddr(Node*, Node*);
@@ -168,12 +164,6 @@ void	complexgen(Node*, Node*);
 void	complexbool(int, Node*, Node*, int, Prog*);
 
 /*
- * gobj.c
- */
-void	data(void);
-void	text(void);
-
-/*
  * list.c
  */
 int	Aconv(Fmt*);
@@ -185,3 +175,5 @@ void	listinit(void);
 
 void	zaddr(Biobuf*, Addr*, int, int);
 
+#pragma	varargck	type	"D"	Addr*
+#pragma	varargck	type	"lD"	Addr*
diff --git a/src/cmd/8g/ggen.c b/src/cmd/8g/ggen.c
index 108c493aa..6a4570199 100644
--- a/src/cmd/8g/ggen.c
+++ b/src/cmd/8g/ggen.c
@@ -4,6 +4,8 @@
 
 #undef	EXTERN
 #define	EXTERN
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
 #include "opt.h"
 
@@ -26,10 +28,10 @@ markautoused(Prog* p)
 {
 	for (; p; p = p->link) {
 		if (p->from.type == D_AUTO && p->from.node)
-			p->from.node->used++;
+			p->from.node->used = 1;
 
 		if (p->to.type == D_AUTO && p->to.node)
-			p->to.node->used++;
+			p->to.node->used = 1;
 	}
 }
 
@@ -429,7 +431,6 @@ hard:
 	if(nr->ullman >= nl->ullman || nl->addable) {
 		mgen(nr, &n2, N);
 		nr = &n2;
-		nr = &n2;
 	} else {
 		tempname(&n2, nr->type);
 		cgen(nr, &n2);
@@ -483,8 +484,8 @@ void
 dodiv(int op, Node *nl, Node *nr, Node *res, Node *ax, Node *dx)
 {
 	int check;
-	Node n1, t1, t2, n4, nz;
-	Type *t;
+	Node n1, t1, t2, t3, t4, n4, nz;
+	Type *t, *t0;
 	Prog *p1, *p2, *p3;
 
 	// Have to be careful about handling
@@ -496,6 +497,7 @@ dodiv(int op, Node *nl, Node *nr, Node *res, Node *ax, Node *dx)
 	// For int32 and int64, use explicit test.
 	// Could use int64 hw for int32.
 	t = nl->type;
+	t0 = t;
 	check = 0;
 	if(issigned[t->etype]) {
 		check = 1;
@@ -514,8 +516,18 @@ dodiv(int op, Node *nl, Node *nr, Node *res, Node *ax, Node *dx)
 
 	tempname(&t1, t);
 	tempname(&t2, t);
-	cgen(nl, &t1);
-	cgen(nr, &t2);
+	if(t0 != t) {
+		tempname(&t3, t0);
+		tempname(&t4, t0);
+		cgen(nl, &t3);
+		cgen(nr, &t4);
+		// Convert.
+		gmove(&t3, &t1);
+		gmove(&t4, &t2);
+	} else {
+		cgen(nl, &t1);
+		cgen(nr, &t2);
+	}
 
 	if(!samereg(ax, res) && !samereg(dx, res))
 		regalloc(&n1, t, res);
diff --git a/src/cmd/8g/gobj.c b/src/cmd/8g/gobj.c
index 31c42a3f2..d8c8f5ab9 100644
--- a/src/cmd/8g/gobj.c
+++ b/src/cmd/8g/gobj.c
@@ -28,6 +28,8 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
 
 void
@@ -276,54 +278,6 @@ dumpfuncs(void)
 	}
 }
 
-/* deferred DATA output */
-static Prog *strdat;
-static Prog *estrdat;
-static int gflag;
-static Prog *savepc;
-
-void
-data(void)
-{
-	gflag = debug['g'];
-	debug['g'] = 0;
-
-	if(estrdat == nil) {
-		strdat = mal(sizeof(*pc));
-		clearp(strdat);
-		estrdat = strdat;
-	}
-	if(savepc)
-		fatal("data phase error");
-	savepc = pc;
-	pc = estrdat;
-}
-
-void
-text(void)
-{
-	if(!savepc)
-		fatal("text phase error");
-	debug['g'] = gflag;
-	estrdat = pc;
-	pc = savepc;
-	savepc = nil;
-}
-
-void
-dumpdata(void)
-{
-	Prog *p;
-
-	if(estrdat == nil)
-		return;
-	*pc = *strdat;
-	if(gflag)
-		for(p=pc; p!=estrdat; p=p->link)
-			print("%P\n", p);
-	pc = estrdat;
-}
-
 int
 dsname(Sym *s, int off, char *t, int n)
 {
@@ -354,6 +308,7 @@ datastring(char *s, int len, Addr *a)
 	sym = stringsym(s, len);
 	a->type = D_EXTERN;
 	a->sym = sym;
+	a->node = sym->def;
 	a->offset = widthptr+4;  // skip header
 	a->etype = TINT32;
 }
@@ -370,6 +325,7 @@ datagostring(Strlit *sval, Addr *a)
 	sym = stringsym(sval->s, sval->len);
 	a->type = D_EXTERN;
 	a->sym = sym;
+	a->node = sym->def;
 	a->offset = 0;  // header
 	a->etype = TINT32;
 }
@@ -380,6 +336,17 @@ gdata(Node *nam, Node *nr, int wid)
 	Prog *p;
 	vlong v;
 
+	if(nr->op == OLITERAL) {
+		switch(nr->val.ctype) {
+		case CTCPLX:
+			gdatacomplex(nam, nr->val.u.cval);
+			return;
+		case CTSTR:
+			gdatastring(nam, nr->val.u.sval);
+			return;
+		}
+	}
+
 	if(wid == 8 && is64(nr->type)) {
 		v = mpgetfix(nr->val.u.xval);
 		p = gins(ADATA, nam, nodintconst(v));
@@ -547,6 +514,8 @@ genembedtramp(Type *rcvr, Type *method, Sym *newnam, int iface)
 	Prog *p;
 	Type *f;
 
+	USED(iface);
+
 	e = method->sym;
 	for(d=0; d<nelem(dotlist); d++) {
 		c = adddot1(e, rcvr, d, nil, 0);
@@ -626,7 +595,6 @@ out:
 		// but 6l has a bug, and it can't handle
 		// JMP instructions too close to the top of
 		// a new function.
-		p = pc;
 		gins(ANOP, N, N);
 	}
 
diff --git a/src/cmd/8g/gsubr.c b/src/cmd/8g/gsubr.c
index a35c81eb1..5e89af04a 100644
--- a/src/cmd/8g/gsubr.c
+++ b/src/cmd/8g/gsubr.c
@@ -28,6 +28,8 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
 
 // TODO(rsc): Can make this bigger if we move
@@ -48,6 +50,10 @@ clearp(Prog *p)
 	pcloc++;
 }
 
+static int ddumped;
+static Prog *dfirst;
+static Prog *dpc;
+
 /*
  * generate and return proc with p->as = as,
  * linked into program.  pc is next instruction.
@@ -57,10 +63,22 @@ prog(int as)
 {
 	Prog *p;
 
-	p = pc;
-	pc = mal(sizeof(*pc));
-
-	clearp(pc);
+	if(as == ADATA || as == AGLOBL) {
+		if(ddumped)
+			fatal("already dumped data");
+		if(dpc == nil) {
+			dpc = mal(sizeof(*dpc));
+			dfirst = dpc;
+		}
+		p = dpc;
+		dpc = mal(sizeof(*dpc));
+		p->link = dpc;
+	} else {
+		p = pc;
+		pc = mal(sizeof(*pc));
+		clearp(pc);
+		p->link = pc;
+	}
 
 	if(lineno == 0) {
 		if(debug['K'])
@@ -69,10 +87,21 @@ prog(int as)
 
 	p->as = as;
 	p->lineno = lineno;
-	p->link = pc;
 	return p;
 }
 
+void
+dumpdata(void)
+{
+	ddumped = 1;
+	if(dfirst == nil)
+		return;
+	newplist();
+	*pc = *dfirst;
+	pc = dpc;
+	clearp(pc);
+}
+
 /*
  * generate a branch.
  * t is ignored.
@@ -82,6 +111,7 @@ gbranch(int as, Type *t)
 {
 	Prog *p;
 
+	USED(t);
 	p = prog(as);
 	p->to.type = D_BRANCH;
 	p->to.branch = P;
@@ -202,6 +232,8 @@ ggloblnod(Node *nam, int32 width)
 	p->to.offset = width;
 	if(nam->readonly)
 		p->from.scale = RODATA;
+	if(nam->type != T && !haspointers(nam->type))
+		p->from.scale |= NOPTR;
 }
 
 void
@@ -753,7 +785,7 @@ ginit(void)
 		reg[resvd[i]]++;
 }
 
-ulong regpc[D_NONE];
+uintptr regpc[D_NONE];
 
 void
 gclean(void)
@@ -822,7 +854,7 @@ regalloc(Node *n, Type *t, Node *o)
 
 		fprint(2, "registers allocated at\n");
 		for(i=D_AX; i<=D_DI; i++)
-			fprint(2, "\t%R\t%#ux\n", i, regpc[i]);
+			fprint(2, "\t%R\t%#lux\n", i, regpc[i]);
 		yyerror("out of fixed registers");
 		goto err;
 
@@ -832,7 +864,6 @@ regalloc(Node *n, Type *t, Node *o)
 		goto out;
 	}
 	yyerror("regalloc: unknown type %T", t);
-	i = 0;
 
 err:
 	nodreg(n, t, 0);
@@ -842,7 +873,7 @@ out:
 	if (i == D_SP)
 		print("alloc SP\n");
 	if(reg[i] == 0) {
-		regpc[i] = (ulong)__builtin_return_address(0);
+		regpc[i] = (uintptr)getcallerpc(&n);
 		if(i == D_AX || i == D_CX || i == D_DX || i == D_SP) {
 			dump("regalloc-o", o);
 			fatal("regalloc %R", i);
@@ -864,7 +895,7 @@ regfree(Node *n)
 	i = n->val.u.reg;
 	if(i == D_SP)
 		return;
-	if(i < 0 || i >= sizeof(reg))
+	if(i < 0 || i >= nelem(reg))
 		fatal("regfree: reg out of range");
 	if(reg[i] <= 0)
 		fatal("regfree: reg not allocated");
@@ -935,8 +966,15 @@ nodarg(Type *t, int fp)
 			fatal("nodarg: offset not computed for %T", t);
 		n->xoffset = t->width;
 		n->addable = 1;
+		n->orig = t->nname;
 		break;
 	}
+	
+	// Rewrite argument named _ to __,
+	// or else the assignment to _ will be
+	// discarded during code generation.
+	if(isblank(n))
+		n->sym = lookup("__");
 
 	switch(fp) {
 	default:
@@ -1005,6 +1043,7 @@ int
 ismem(Node *n)
 {
 	switch(n->op) {
+	case OITAB:
 	case OLEN:
 	case OCAP:
 	case OINDREG:
@@ -1123,6 +1162,7 @@ memname(Node *n, Type *t)
 	strcpy(namebuf, n->sym->name);
 	namebuf[0] = '.';	// keep optimizer from registerizing
 	n->sym = lookup(namebuf);
+	n->orig->sym = n->sym;
 }
 
 void
@@ -1799,6 +1839,7 @@ naddr(Node *n, Addr *a, int canemitcode)
 		a->offset = n->xoffset;
 		a->sym = n->left->sym;
 		a->type = D_PARAM;
+		a->node = n->left->orig;
 		break;
 
 	case ONAME:
@@ -1809,9 +1850,11 @@ naddr(Node *n, Addr *a, int canemitcode)
 			a->width = n->type->width;
 			a->gotype = ngotype(n);
 		}
-		a->pun = n->pun;
 		a->offset = n->xoffset;
 		a->sym = n->sym;
+		a->node = n->orig;
+		//if(a->node >= (Node*)&n)
+		//	fatal("stack node");
 		if(a->sym == S)
 			a->sym = lookup(".noname");
 		if(n->method) {
@@ -1829,8 +1872,6 @@ naddr(Node *n, Addr *a, int canemitcode)
 			break;
 		case PAUTO:
 			a->type = D_AUTO;
-			if (n->sym)
-				a->node = n->orig;
 			break;
 		case PPARAM:
 		case PPARAMOUT:
@@ -1853,6 +1894,7 @@ naddr(Node *n, Addr *a, int canemitcode)
 			a->dval = mpgetflt(n->val.u.fval);
 			break;
 		case CTINT:
+		case CTRUNE:
 			a->sym = S;
 			a->type = D_CONST;
 			a->offset = mpgetfix(n->val.u.xval);
@@ -1887,6 +1929,17 @@ naddr(Node *n, Addr *a, int canemitcode)
 				break;
 			}
 		fatal("naddr: OADDR\n");
+	
+	case OITAB:
+		// itable of interface value
+		naddr(n->left, a, canemitcode);
+		if(a->type == D_CONST && a->offset == 0)
+			break;	// len(nil)
+		a->etype = tptr;
+		a->width = widthptr;
+		if(a->offset >= unmappedzero && a->offset-Array_nel < unmappedzero)
+			checkoffset(a, canemitcode);
+		break;
 
 	case OLEN:
 		// len of string or slice
@@ -1955,5 +2008,9 @@ sudoclean(void)
 int
 sudoaddable(int as, Node *n, Addr *a)
 {
+	USED(as);
+	USED(n);
+	USED(a);
+
 	return 0;
 }
diff --git a/src/cmd/8g/list.c b/src/cmd/8g/list.c
index edb1ece84..88d3d5f7e 100644
--- a/src/cmd/8g/list.c
+++ b/src/cmd/8g/list.c
@@ -28,6 +28,8 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
 
 static	int	sconsize;
@@ -128,7 +130,7 @@ Dconv(Fmt *fp)
 		if(fp->flags & FmtLong) {
 			d1 = a->offset;
 			d2 = a->offset2;
-			snprint(str, sizeof(str), "$%ud-%ud", (ulong)d1, (ulong)d2);
+			snprint(str, sizeof(str), "$%lud-%lud", (ulong)d1, (ulong)d2);
 			break;
 		}
 		snprint(str, sizeof(str), "$%d", a->offset);
diff --git a/src/cmd/8g/opt.h b/src/cmd/8g/opt.h
index 8f31dec3b..ed6eb15ab 100644
--- a/src/cmd/8g/opt.h
+++ b/src/cmd/8g/opt.h
@@ -162,3 +162,5 @@ int32	RtoB(int);
 int32	FtoB(int);
 int	BtoR(int32);
 int	BtoF(int32);
+
+#pragma	varargck	type	"D"	Adr*
diff --git a/src/cmd/8g/peep.c b/src/cmd/8g/peep.c
index 5ad29e1b2..b8a2825e5 100644
--- a/src/cmd/8g/peep.c
+++ b/src/cmd/8g/peep.c
@@ -28,6 +28,8 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
 #include "opt.h"
 
@@ -876,13 +878,12 @@ loop:
 	case 3:	// set
 		if(p->as == p0->as)
 		if(p->from.type == p0->from.type)
-		if(p->from.sym == p0->from.sym)
+		if(p->from.node == p0->from.node)
 		if(p->from.offset == p0->from.offset)
 		if(p->from.scale == p0->from.scale)
 		if(p->from.dval == p0->from.dval)
 		if(p->from.index == p0->from.index) {
 			excise(r);
-			t++;
 			goto loop;
 		}
 		break;
diff --git a/src/cmd/8g/reg.c b/src/cmd/8g/reg.c
index 2b878f62a..29270c820 100644
--- a/src/cmd/8g/reg.c
+++ b/src/cmd/8g/reg.c
@@ -28,9 +28,9 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#include <u.h>
+#include <libc.h>
 #include "gg.h"
-#undef	EXTERN
-#define	EXTERN
 #include "opt.h"
 
 #define	NREGVAR	8
@@ -39,6 +39,8 @@
 
 static	int	first	= 1;
 
+static	void	fixjmp(Prog*);
+
 Reg*
 rega(void)
 {
@@ -89,8 +91,8 @@ setoutvar(void)
 			ovar.b[z] |= bit.b[z];
 		t = structnext(&save);
 	}
-//if(bany(b))
-//print("ovars = %Q\n", &ovar);
+//if(bany(ovar))
+//print("ovars = %Q\n", ovar);
 }
 
 static void
@@ -98,19 +100,19 @@ setaddrs(Bits bit)
 {
 	int i, n;
 	Var *v;
-	Sym *s;
+	Node *node;
 
 	while(bany(&bit)) {
 		// convert each bit to a variable
 		i = bnum(bit);
-		s = var[i].sym;
+		node = var[i].node;
 		n = var[i].name;
 		bit.b[i/32] &= ~(1L<<(i%32));
 
 		// disable all pieces of that variable
 		for(i=0; i<nvar; i++) {
 			v = var+i;
-			if(v->sym == s && v->name == n)
+			if(v->node == node && v->name == n)
 				v->addr = 2;
 		}
 	}
@@ -132,6 +134,8 @@ regopt(Prog *firstp)
 		exregoffset = D_DI;	// no externals
 		first = 0;
 	}
+	
+	fixjmp(firstp);
 
 	// count instructions
 	nr = 0;
@@ -155,7 +159,7 @@ regopt(Prog *firstp)
 	nvar = NREGVAR;
 	memset(var, 0, NREGVAR*sizeof var[0]);
 	for(i=0; i<NREGVAR; i++)
-		var[i].sym = lookup(regname[i]);
+		var[i].node = newname(lookup(regname[i]));
 
 	regbits = RtoB(D_SP);
 	for(z=0; z<BITS; z++) {
@@ -216,6 +220,9 @@ regopt(Prog *firstp)
 		 * funny
 		 */
 		case ALEAL:
+		case AFMOVL: 
+		case AFMOVW:
+		case AFMOVV:
 			setaddrs(bit);
 			break;
 
@@ -694,9 +701,9 @@ brk:
 		if(ostats.ndelmov)
 			print("	%4d delmov\n", ostats.ndelmov);
 		if(ostats.nvar)
-			print("	%4d delmov\n", ostats.nvar);
+			print("	%4d var\n", ostats.nvar);
 		if(ostats.naddr)
-			print("	%4d delmov\n", ostats.naddr);
+			print("	%4d addr\n", ostats.naddr);
 
 		memset(&ostats, 0, sizeof(ostats));
 	}
@@ -725,19 +732,19 @@ addmove(Reg *r, int bn, int rn, int f)
 	v = var + bn;
 
 	a = &p1->to;
-	a->sym = v->sym;
 	a->offset = v->offset;
 	a->etype = v->etype;
 	a->type = v->name;
 	a->gotype = v->gotype;
 	a->node = v->node;
+	a->sym = v->node->sym;
 
 	// need to clean this up with wptr and
 	// some of the defaults
 	p1->as = AMOVL;
 	switch(v->etype) {
 	default:
-		fatal("unknown type\n");
+		fatal("unknown type %E", v->etype);
 	case TINT8:
 	case TUINT8:
 	case TBOOL:
@@ -810,7 +817,7 @@ mkvar(Reg *r, Adr *a)
 	int i, t, n, et, z, w, flag, regu;
 	int32 o;
 	Bits bit;
-	Sym *s;
+	Node *node;
 
 	/*
 	 * mark registers used
@@ -847,10 +854,13 @@ mkvar(Reg *r, Adr *a)
 		break;
 	}
 
-	s = a->sym;
-	if(s == S)
+	node = a->node;
+	if(node == N || node->op != ONAME || node->orig == N)
 		goto none;
-	if(s->name[0] == '.')
+	node = node->orig;
+	if(node->orig != node)
+		fatal("%D: bad node", a);
+	if(node->sym == S || node->sym->name[0] == '.')
 		goto none;
 	et = a->etype;
 	o = a->offset;
@@ -859,7 +869,7 @@ mkvar(Reg *r, Adr *a)
 	flag = 0;
 	for(i=0; i<nvar; i++) {
 		v = var+i;
-		if(v->sym == s && v->name == n) {
+		if(v->node == node && v->name == n) {
 			if(v->offset == o)
 			if(v->etype == et)
 			if(v->width == w)
@@ -868,7 +878,7 @@ mkvar(Reg *r, Adr *a)
 			// if they overlap, disable both
 			if(overlap(v->offset, v->width, o, w)) {
 				if(debug['R'])
-					print("disable %s\n", v->sym->name);
+					print("disable %s\n", node->sym->name);
 				v->addr = 1;
 				flag = 1;
 			}
@@ -882,7 +892,7 @@ mkvar(Reg *r, Adr *a)
 	}
 
 	if(nvar >= NVAR) {
-		if(debug['w'] > 1 && s)
+		if(debug['w'] > 1 && node != N)
 			fatal("variable not optimized: %D", a);
 		goto none;
 	}
@@ -890,17 +900,16 @@ mkvar(Reg *r, Adr *a)
 	i = nvar;
 	nvar++;
 	v = var+i;
-	v->sym = s;
 	v->offset = o;
 	v->name = n;
 	v->gotype = a->gotype;
 	v->etype = et;
 	v->width = w;
 	v->addr = flag;		// funny punning
-	v->node = a->node;
+	v->node = node;
 
 	if(debug['R'])
-		print("bit=%2d et=%2d w=%d+%d %S %D flag=%d\n", i, et, o, w, s, a, v->addr);
+		print("bit=%2d et=%2d w=%d+%d %#N %D flag=%d\n", i, et, o, w, node, a, v->addr);
 	ostats.nvar++;
 
 	bit = blsh(i);
@@ -959,6 +968,13 @@ prop(Reg *r, Bits ref, Bits cal)
 				ref.b[z] = 0;
 			}
 			break;
+
+		default:
+			// Work around for issue 1304:
+			// flush modified globals before each instruction.
+			for(z=0; z<BITS; z++)
+				cal.b[z] |= externs.b[z];
+			break;
 		}
 		for(z=0; z<BITS; z++) {
 			ref.b[z] = (ref.b[z] & ~r1->set.b[z]) |
@@ -1095,10 +1111,12 @@ loopit(Reg *r, int32 nr)
 		r1 = rpo2r[i];
 		me = r1->rpo;
 		d = -1;
-		if(r1->p1 != R && r1->p1->rpo < me)
+		// rpo2r[r->rpo] == r protects against considering dead code,
+		// which has r->rpo == 0.
+		if(r1->p1 != R && rpo2r[r1->p1->rpo] == r1->p1 && r1->p1->rpo < me)
 			d = r1->p1->rpo;
 		for(r1 = r1->p2; r1 != nil; r1 = r1->p2link)
-			if(r1->rpo < me)
+			if(rpo2r[r1->rpo] == r1 && r1->rpo < me)
 				d = rpolca(idom, d, r1->rpo);
 		idom[i] = d;
 	}
@@ -1482,7 +1500,7 @@ dumpone(Reg *r)
 		if(bany(&r->refahead))
 			print(" ra:%Q ", r->refahead);
 		if(bany(&r->calbehind))
-			print("cb:%Q ", r->calbehind);
+			print(" cb:%Q ", r->calbehind);
 		if(bany(&r->calahead))
 			print(" ca:%Q ", r->calahead);
 		if(bany(&r->regdiff))
@@ -1542,3 +1560,123 @@ noreturn(Prog *p)
 			return 1;
 	return 0;
 }
+
+/*
+ * the code generator depends on being able to write out JMP
+ * instructions that it can jump to now but fill in later.
+ * the linker will resolve them nicely, but they make the code
+ * longer and more difficult to follow during debugging.
+ * remove them.
+ */
+
+/* what instruction does a JMP to p eventually land on? */
+static Prog*
+chasejmp(Prog *p, int *jmploop)
+{
+	int n;
+
+	n = 0;
+	while(p != P && p->as == AJMP && p->to.type == D_BRANCH) {
+		if(++n > 10) {
+			*jmploop = 1;
+			break;
+		}
+		p = p->to.branch;
+	}
+	return p;
+}
+
+/*
+ * reuse reg pointer for mark/sweep state.
+ * leave reg==nil at end because alive==nil.
+ */
+#define alive ((void*)0)
+#define dead ((void*)1)
+
+/* mark all code reachable from firstp as alive */
+static void
+mark(Prog *firstp)
+{
+	Prog *p;
+	
+	for(p=firstp; p; p=p->link) {
+		if(p->reg != dead)
+			break;
+		p->reg = alive;
+		if(p->as != ACALL && p->to.type == D_BRANCH && p->to.branch)
+			mark(p->to.branch);
+		if(p->as == AJMP || p->as == ARET || (p->as == ACALL && noreturn(p)))
+			break;
+	}
+}
+
+static void
+fixjmp(Prog *firstp)
+{
+	int jmploop;
+	Prog *p, *last;
+	
+	if(debug['R'] && debug['v'])
+		print("\nfixjmp\n");
+
+	// pass 1: resolve jump to AJMP, mark all code as dead.
+	jmploop = 0;
+	for(p=firstp; p; p=p->link) {
+		if(debug['R'] && debug['v'])
+			print("%P\n", p);
+		if(p->as != ACALL && p->to.type == D_BRANCH && p->to.branch && p->to.branch->as == AJMP) {
+			p->to.branch = chasejmp(p->to.branch, &jmploop);
+			if(debug['R'] && debug['v'])
+				print("->%P\n", p);
+		}
+		p->reg = dead;
+	}
+	if(debug['R'] && debug['v'])
+		print("\n");
+
+	// pass 2: mark all reachable code alive
+	mark(firstp);
+	
+	// pass 3: delete dead code (mostly JMPs).
+	last = nil;
+	for(p=firstp; p; p=p->link) {
+		if(p->reg == dead) {
+			if(p->link == P && p->as == ARET && last && last->as != ARET) {
+				// This is the final ARET, and the code so far doesn't have one.
+				// Let it stay.
+			} else {
+				if(debug['R'] && debug['v'])
+					print("del %P\n", p);
+				continue;
+			}
+		}
+		if(last)
+			last->link = p;
+		last = p;
+	}
+	last->link = P;
+	
+	// pass 4: elide JMP to next instruction.
+	// only safe if there are no jumps to JMPs anymore.
+	if(!jmploop) {
+		last = nil;
+		for(p=firstp; p; p=p->link) {
+			if(p->as == AJMP && p->to.type == D_BRANCH && p->to.branch == p->link) {
+				if(debug['R'] && debug['v'])
+					print("del %P\n", p);
+				continue;
+			}
+			if(last)
+				last->link = p;
+			last = p;
+		}
+		last->link = P;
+	}
+	
+	if(debug['R'] && debug['v']) {
+		print("\n");
+		for(p=firstp; p; p=p->link)
+			print("%P\n", p);
+		print("\n");
+	}
+}