github.com/xushiwei/go@v0.0.0-20130601165731-2b9d83f45bc9/src/cmd/6g/gobj.c (about)

     1  // Derived from Inferno utils/6c/swt.c
     2  // http://code.google.com/p/inferno-os/source/browse/utils/6c/swt.c
     3  //
     4  //	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
     5  //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
     6  //	Portions Copyright © 1997-1999 Vita Nuova Limited
     7  //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
     8  //	Portions Copyright © 2004,2006 Bruce Ellis
     9  //	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
    10  //	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
    11  //	Portions Copyright © 2009 The Go Authors.  All rights reserved.
    12  //
    13  // Permission is hereby granted, free of charge, to any person obtaining a copy
    14  // of this software and associated documentation files (the "Software"), to deal
    15  // in the Software without restriction, including without limitation the rights
    16  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    17  // copies of the Software, and to permit persons to whom the Software is
    18  // furnished to do so, subject to the following conditions:
    19  //
    20  // The above copyright notice and this permission notice shall be included in
    21  // all copies or substantial portions of the Software.
    22  //
    23  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    24  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    25  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
    26  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    27  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    28  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    29  // THE SOFTWARE.
    30  
    31  #include <u.h>
    32  #include <libc.h>
    33  #include "gg.h"
    34  
    35  void
    36  zname(Biobuf *b, Sym *s, int t)
    37  {
    38  	Bputc(b, ANAME);	/* as */
    39  	Bputc(b, ANAME>>8);	/* as */
    40  	Bputc(b, t);		/* type */
    41  	Bputc(b, s->sym);	/* sym */
    42  
    43  	Bputname(b, s);
    44  }
    45  
    46  void
    47  zfile(Biobuf *b, char *p, int n)
    48  {
    49  	Bputc(b, ANAME);
    50  	Bputc(b, ANAME>>8);
    51  	Bputc(b, D_FILE);
    52  	Bputc(b, 1);
    53  	Bputc(b, '<');
    54  	Bwrite(b, p, n);
    55  	Bputc(b, 0);
    56  }
    57  
    58  void
    59  zhist(Biobuf *b, int line, vlong offset)
    60  {
    61  	Addr a;
    62  
    63  	Bputc(b, AHISTORY);
    64  	Bputc(b, AHISTORY>>8);
    65  	Bputc(b, line);
    66  	Bputc(b, line>>8);
    67  	Bputc(b, line>>16);
    68  	Bputc(b, line>>24);
    69  	zaddr(b, &zprog.from, 0, 0);
    70  	a = zprog.to;
    71  	if(offset != 0) {
    72  		a.offset = offset;
    73  		a.type = D_CONST;
    74  	}
    75  	zaddr(b, &a, 0, 0);
    76  }
    77  
    78  void
    79  zaddr(Biobuf *b, Addr *a, int s, int gotype)
    80  {
    81  	int32 l;
    82  	uint64 e;
    83  	int i, t;
    84  	char *n;
    85  
    86  	t = 0;
    87  	if(a->index != D_NONE || a->scale != 0)
    88  		t |= T_INDEX;
    89  	if(s != 0)
    90  		t |= T_SYM;
    91  	if(gotype != 0)
    92  		t |= T_GOTYPE;
    93  
    94  	switch(a->type) {
    95  
    96  	case D_BRANCH:
    97  		if(a->u.branch == nil)
    98  			fatal("unpatched branch");
    99  		a->offset = a->u.branch->loc;
   100  
   101  	default:
   102  		t |= T_TYPE;
   103  
   104  	case D_NONE:
   105  		if(a->offset != 0) {
   106  			t |= T_OFFSET;
   107  			l = a->offset;
   108  			if((vlong)l != a->offset)
   109  				t |= T_64;
   110  		}
   111  		break;
   112  	case D_FCONST:
   113  		t |= T_FCONST;
   114  		break;
   115  	case D_SCONST:
   116  		t |= T_SCONST;
   117  		break;
   118  	}
   119  	Bputc(b, t);
   120  
   121  	if(t & T_INDEX) {	/* implies index, scale */
   122  		Bputc(b, a->index);
   123  		Bputc(b, a->scale);
   124  	}
   125  	if(t & T_OFFSET) {	/* implies offset */
   126  		l = a->offset;
   127  		Bputc(b, l);
   128  		Bputc(b, l>>8);
   129  		Bputc(b, l>>16);
   130  		Bputc(b, l>>24);
   131  		if(t & T_64) {
   132  			l = a->offset>>32;
   133  			Bputc(b, l);
   134  			Bputc(b, l>>8);
   135  			Bputc(b, l>>16);
   136  			Bputc(b, l>>24);
   137  		}
   138  	}
   139  	if(t & T_SYM)		/* implies sym */
   140  		Bputc(b, s);
   141  	if(t & T_FCONST) {
   142  		ieeedtod(&e, a->u.dval);
   143  		l = e;
   144  		Bputc(b, l);
   145  		Bputc(b, l>>8);
   146  		Bputc(b, l>>16);
   147  		Bputc(b, l>>24);
   148  		l = e >> 32;
   149  		Bputc(b, l);
   150  		Bputc(b, l>>8);
   151  		Bputc(b, l>>16);
   152  		Bputc(b, l>>24);
   153  		return;
   154  	}
   155  	if(t & T_SCONST) {
   156  		n = a->u.sval;
   157  		for(i=0; i<NSNAME; i++) {
   158  			Bputc(b, *n);
   159  			n++;
   160  		}
   161  		return;
   162  	}
   163  	if(t & T_TYPE)
   164  		Bputc(b, a->type);
   165  	if(t & T_GOTYPE)
   166  		Bputc(b, gotype);
   167  }
   168  
   169  static struct {
   170  	struct { Sym *sym; short type; } h[NSYM];
   171  	int sym;
   172  } z;
   173  
   174  static void
   175  zsymreset(void)
   176  {
   177  	for(z.sym=0; z.sym<NSYM; z.sym++) {
   178  		z.h[z.sym].sym = S;
   179  		z.h[z.sym].type = 0;
   180  	}
   181  	z.sym = 1;
   182  }
   183  
   184  static int
   185  zsym(Sym *s, int t, int *new)
   186  {
   187  	int i;
   188  
   189  	*new = 0;
   190  	if(s == S)
   191  		return 0;
   192  
   193  	i = s->sym;
   194  	if(i < 0 || i >= NSYM)
   195  		i = 0;
   196  	if(z.h[i].type == t && z.h[i].sym == s)
   197  		return i;
   198  	i = z.sym;
   199  	s->sym = i;
   200  	zname(bout, s, t);
   201  	z.h[i].sym = s;
   202  	z.h[i].type = t;
   203  	if(++z.sym >= NSYM)
   204  		z.sym = 1;
   205  	*new = 1;
   206  	return i;
   207  }
   208  
   209  static int
   210  zsymaddr(Addr *a, int *new)
   211  {
   212  	int t;
   213  
   214  	t = a->type;
   215  	if(t == D_ADDR)
   216  		t = a->index;
   217  	return zsym(a->sym, t, new);
   218  }
   219  
   220  void
   221  dumpfuncs(void)
   222  {
   223  	Plist *pl;
   224  	int sf, st, gf, gt, new;
   225  	Sym *s;
   226  	Prog *p;
   227  
   228  	zsymreset();
   229  
   230  	// fix up pc
   231  	pcloc = 0;
   232  	for(pl=plist; pl!=nil; pl=pl->link) {
   233  		if(isblank(pl->name))
   234  			continue;
   235  		for(p=pl->firstpc; p!=P; p=p->link) {
   236  			p->loc = pcloc;
   237  			if(p->as != ADATA && p->as != AGLOBL)
   238  				pcloc++;
   239  		}
   240  	}
   241  
   242  	// put out functions
   243  	for(pl=plist; pl!=nil; pl=pl->link) {
   244  		if(isblank(pl->name))
   245  			continue;
   246  
   247  		// -S prints code; -SS prints code and data
   248  		if(debug['S'] && (pl->name || debug['S']>1)) {
   249  			s = S;
   250  			if(pl->name != N)
   251  				s = pl->name->sym;
   252  			print("\n--- prog list \"%S\" ---\n", s);
   253  			for(p=pl->firstpc; p!=P; p=p->link)
   254  				print("%P\n", p);
   255  		}
   256  
   257  		for(p=pl->firstpc; p!=P; p=p->link) {
   258  			for(;;) {
   259  				sf = zsymaddr(&p->from, &new);
   260  				gf = zsym(p->from.gotype, D_EXTERN, &new);
   261  				if(new && sf == gf)
   262  					continue;
   263  				st = zsymaddr(&p->to, &new);
   264  				if(new && (st == sf || st == gf))
   265  					continue;
   266  				gt = zsym(p->to.gotype, D_EXTERN, &new);
   267  				if(new && (gt == sf || gt == gf || gt == st))
   268  					continue;
   269  				break;
   270  			}
   271  
   272  			Bputc(bout, p->as);
   273  			Bputc(bout, p->as>>8);
   274  			Bputc(bout, p->lineno);
   275  			Bputc(bout, p->lineno>>8);
   276  			Bputc(bout, p->lineno>>16);
   277  			Bputc(bout, p->lineno>>24);
   278  			zaddr(bout, &p->from, sf, gf);
   279  			zaddr(bout, &p->to, st, gt);
   280  		}
   281  	}
   282  }
   283  
   284  int
   285  dsname(Sym *s, int off, char *t, int n)
   286  {
   287  	Prog *p;
   288  
   289  	p = gins(ADATA, N, N);
   290  	p->from.type = D_EXTERN;
   291  	p->from.index = D_NONE;
   292  	p->from.offset = off;
   293  	p->from.scale = n;
   294  	p->from.sym = s;
   295  	
   296  	p->to.type = D_SCONST;
   297  	p->to.index = D_NONE;
   298  	memmove(p->to.u.sval, t, n);
   299  	return off + n;
   300  }
   301  
   302  /*
   303   * make a refer to the data s, s+len
   304   * emitting DATA if needed.
   305   */
   306  void
   307  datastring(char *s, int len, Addr *a)
   308  {
   309  	Sym *sym;
   310  	
   311  	sym = stringsym(s, len);
   312  	a->type = D_EXTERN;
   313  	a->sym = sym;
   314  	a->node = sym->def;
   315  	a->offset = widthptr+widthint;  // skip header
   316  	a->etype = simtype[TINT];
   317  }
   318  
   319  /*
   320   * make a refer to the string sval,
   321   * emitting DATA if needed.
   322   */
   323  void
   324  datagostring(Strlit *sval, Addr *a)
   325  {
   326  	Sym *sym;
   327  
   328  	sym = stringsym(sval->s, sval->len);
   329  	a->type = D_EXTERN;
   330  	a->sym = sym;
   331  	a->node = sym->def;
   332  	a->offset = 0;  // header
   333  	a->etype = TINT32;
   334  }
   335  
   336  void
   337  gdata(Node *nam, Node *nr, int wid)
   338  {
   339  	Prog *p;
   340  
   341  	if(nr->op == OLITERAL) {
   342  		switch(nr->val.ctype) {
   343  		case CTCPLX:
   344  			gdatacomplex(nam, nr->val.u.cval);
   345  			return;
   346  		case CTSTR:
   347  			gdatastring(nam, nr->val.u.sval);
   348  			return;
   349  		}
   350  	}
   351  	p = gins(ADATA, nam, nr);
   352  	p->from.scale = wid;
   353  }
   354  
   355  void
   356  gdatacomplex(Node *nam, Mpcplx *cval)
   357  {
   358  	Prog *p;
   359  	int w;
   360  
   361  	w = cplxsubtype(nam->type->etype);
   362  	w = types[w]->width;
   363  
   364  	p = gins(ADATA, nam, N);
   365  	p->from.scale = w;
   366  	p->to.type = D_FCONST;
   367  	p->to.u.dval = mpgetflt(&cval->real);
   368  
   369  	p = gins(ADATA, nam, N);
   370  	p->from.scale = w;
   371  	p->from.offset += w;
   372  	p->to.type = D_FCONST;
   373  	p->to.u.dval = mpgetflt(&cval->imag);
   374  }
   375  
   376  void
   377  gdatastring(Node *nam, Strlit *sval)
   378  {
   379  	Prog *p;
   380  	Node nod1;
   381  
   382  	p = gins(ADATA, nam, N);
   383  	datastring(sval->s, sval->len, &p->to);
   384  	p->from.scale = types[tptr]->width;
   385  	p->to.index = p->to.type;
   386  	p->to.type = D_ADDR;
   387  //print("%P\n", p);
   388  
   389  	nodconst(&nod1, types[TINT], sval->len);
   390  	p = gins(ADATA, nam, &nod1);
   391  	p->from.scale = widthint;
   392  	p->from.offset += widthptr;
   393  }
   394  
   395  int
   396  dstringptr(Sym *s, int off, char *str)
   397  {
   398  	Prog *p;
   399  
   400  	off = rnd(off, widthptr);
   401  	p = gins(ADATA, N, N);
   402  	p->from.type = D_EXTERN;
   403  	p->from.index = D_NONE;
   404  	p->from.sym = s;
   405  	p->from.offset = off;
   406  	p->from.scale = widthptr;
   407  
   408  	datastring(str, strlen(str)+1, &p->to);
   409  	p->to.index = p->to.type;
   410  	p->to.type = D_ADDR;
   411  	p->to.etype = simtype[TINT];
   412  	off += widthptr;
   413  
   414  	return off;
   415  }
   416  
   417  int
   418  dgostrlitptr(Sym *s, int off, Strlit *lit)
   419  {
   420  	Prog *p;
   421  
   422  	if(lit == nil)
   423  		return duintptr(s, off, 0);
   424  
   425  	off = rnd(off, widthptr);
   426  	p = gins(ADATA, N, N);
   427  	p->from.type = D_EXTERN;
   428  	p->from.index = D_NONE;
   429  	p->from.sym = s;
   430  	p->from.offset = off;
   431  	p->from.scale = widthptr;
   432  	datagostring(lit, &p->to);
   433  	p->to.index = p->to.type;
   434  	p->to.type = D_ADDR;
   435  	p->to.etype = simtype[TINT];
   436  	off += widthptr;
   437  
   438  	return off;
   439  }
   440  
   441  int
   442  dgostringptr(Sym *s, int off, char *str)
   443  {
   444  	int n;
   445  	Strlit *lit;
   446  
   447  	if(str == nil)
   448  		return duintptr(s, off, 0);
   449  
   450  	n = strlen(str);
   451  	lit = mal(sizeof *lit + n);
   452  	strcpy(lit->s, str);
   453  	lit->len = n;
   454  	return dgostrlitptr(s, off, lit);
   455  }
   456  
   457  int
   458  duintxx(Sym *s, int off, uint64 v, int wid)
   459  {
   460  	Prog *p;
   461  
   462  	off = rnd(off, wid);
   463  
   464  	p = gins(ADATA, N, N);
   465  	p->from.type = D_EXTERN;
   466  	p->from.index = D_NONE;
   467  	p->from.sym = s;
   468  	p->from.offset = off;
   469  	p->from.scale = wid;
   470  	p->to.type = D_CONST;
   471  	p->to.index = D_NONE;
   472  	p->to.offset = v;
   473  	off += wid;
   474  
   475  	return off;
   476  }
   477  
   478  int
   479  dsymptr(Sym *s, int off, Sym *x, int xoff)
   480  {
   481  	Prog *p;
   482  
   483  	off = rnd(off, widthptr);
   484  
   485  	p = gins(ADATA, N, N);
   486  	p->from.type = D_EXTERN;
   487  	p->from.index = D_NONE;
   488  	p->from.sym = s;
   489  	p->from.offset = off;
   490  	p->from.scale = widthptr;
   491  	p->to.type = D_ADDR;
   492  	p->to.index = D_EXTERN;
   493  	p->to.sym = x;
   494  	p->to.offset = xoff;
   495  	off += widthptr;
   496  
   497  	return off;
   498  }
   499  
   500  void
   501  genembedtramp(Type *rcvr, Type *method, Sym *newnam, int iface)
   502  {
   503  	Sym *e;
   504  	int c, d, mov, add, loaded;
   505  	int64 o;
   506  	Prog *p;
   507  	Type *f;
   508  	
   509  	USED(iface);
   510  
   511  	if(0 && debug['r'])
   512  		print("genembedtramp %T %T %S\n", rcvr, method, newnam);
   513  
   514  	e = method->sym;
   515  	for(d=0; d<nelem(dotlist); d++) {
   516  		c = adddot1(e, rcvr, d, nil, 0);
   517  		if(c == 1)
   518  			goto out;
   519  	}
   520  	fatal("genembedtramp %T.%S", rcvr, method->sym);
   521  
   522  out:
   523  	newplist()->name = newname(newnam);
   524  
   525  	//TEXT	main·S_test2(SB),7,$0
   526  	p = pc;
   527  	gins(ATEXT, N, N);
   528  	p->from.type = D_EXTERN;
   529  	p->from.sym = newnam;
   530  	p->to.type = D_CONST;
   531  	p->to.offset = 0;
   532  	p->from.scale = 7;
   533  //print("1. %P\n", p);
   534  
   535  	mov = AMOVQ;
   536  	add = AADDQ;
   537  	loaded = 0;
   538  	o = 0;
   539  	for(c=d-1; c>=0; c--) {
   540  		f = dotlist[c].field;
   541  		o += f->width;
   542  		if(!isptr[f->type->etype])
   543  			continue;
   544  		if(!loaded) {
   545  			loaded = 1;
   546  			//MOVQ	8(SP), AX
   547  			p = pc;
   548  			gins(mov, N, N);
   549  			p->from.type = D_INDIR+D_SP;
   550  			p->from.offset = widthptr;
   551  			p->to.type = D_AX;
   552  //print("2. %P\n", p);
   553  		}
   554  
   555  		//MOVQ	o(AX), AX
   556  		p = pc;
   557  		gins(mov, N, N);
   558  		p->from.type = D_INDIR+D_AX;
   559  		p->from.offset = o;
   560  		p->to.type = D_AX;
   561  //print("3. %P\n", p);
   562  		o = 0;
   563  	}
   564  	if(o != 0) {
   565  		//ADDQ	$XX, AX
   566  		p = pc;
   567  		gins(add, N, N);
   568  		p->from.type = D_CONST;
   569  		p->from.offset = o;
   570  		if(loaded)
   571  			p->to.type = D_AX;
   572  		else {
   573  			p->to.type = D_INDIR+D_SP;
   574  			p->to.offset = widthptr;
   575  		}
   576  //print("4. %P\n", p);
   577  	}
   578  
   579  	//MOVQ	AX, 8(SP)
   580  	if(loaded) {
   581  		p = pc;
   582  		gins(mov, N, N);
   583  		p->from.type = D_AX;
   584  		p->to.type = D_INDIR+D_SP;
   585  		p->to.offset = widthptr;
   586  //print("5. %P\n", p);
   587  	} else {
   588  		// TODO(rsc): obviously this is unnecessary,
   589  		// but 6l has a bug, and it can't handle
   590  		// JMP instructions too close to the top of
   591  		// a new function.
   592  		gins(ANOP, N, N);
   593  	}
   594  
   595  	f = dotlist[0].field;
   596  	//JMP	main·*Sub_test2(SB)
   597  	if(isptr[f->type->etype])
   598  		f = f->type;
   599  	p = pc;
   600  	gins(AJMP, N, N);
   601  	p->to.type = D_EXTERN;
   602  	p->to.sym = methodsym(method->sym, ptrto(f->type), 0);
   603  //print("6. %P\n", p);
   604  
   605  	pc->as = ARET;	// overwrite AEND
   606  }
   607  
   608  void
   609  nopout(Prog *p)
   610  {
   611  	p->as = ANOP;
   612  }
   613