src/cmd/ld/pobj.c - go - Git at Google

 // Inferno utils/6l/obj.c
 // http://code.google.com/p/inferno-os/source/browse/utils/6l/obj.c
 //
 //	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)
 //	Portions Copyright © 2004,2006 Bruce Ellis
 //	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
 //	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
 //	Portions Copyright © 2009 The Go Authors.  All rights reserved.
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
 // in the Software without restriction, including without limitation the rights
 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 // copies of the Software, and to permit persons to whom the Software is
 // furnished to do so, subject to the following conditions:
 //
 // The above copyright notice and this permission notice shall be included in
 // all copies or substantial portions of the Software.
 //
 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.

 // Reading object files.

 #define	EXTERN
 #include	<u.h>
 #include	<libc.h>
 #include	<bio.h>
 #include	<link.h>
 #include	"lib.h"
 #include	"elf.h"
 #include	"macho.h"
 #include	"dwarf.h"
 #include	"pe.h"
 #include	<ar.h>

 char	*noname		= "<none>";
 char*	paramspace	= "FP";

 void
 ldmain(int argc, char **argv)
 {
 	int i;

 	ctxt = linknew(thelinkarch);
 	ctxt->thechar = thearch.thechar;
 	ctxt->thestring = thestring;
 	ctxt->diag = diag;
 	ctxt->bso = &bso;

 	Binit(&bso, 1, OWRITE);
 	thearch.listinit();
 	memset(debug, 0, sizeof(debug));
 	nerrors = 0;
 	outfile = nil;
 	HEADTYPE = -1;
 	INITTEXT = -1;
 	INITDAT = -1;
 	INITRND = -1;
 	INITENTRY = 0;
 	linkmode = LinkAuto;

 	// For testing behavior of go command when tools crash.
 	// Undocumented, not in standard flag parser to avoid
 	// exposing in usage message.
 	for(i=1; i<argc; i++)
 		if(strcmp(argv[i], "-crash_for_testing") == 0)
 			*(volatile int*)0 = 0;

 	if(thearch.thechar == '5' && ctxt->goarm == 5)
 		debug['F'] = 1;

 	flagcount("1", "use alternate profiling code", &debug['1']);
 	if(thearch.thechar == '6')
 		flagcount("8", "assume 64-bit addresses", &debug['8']);
 	flagfn1("B", "info: define ELF NT_GNU_BUILD_ID note", addbuildinfo);
 	flagcount("C", "check Go calls to C code", &debug['C']);
 	flagint64("D", "addr: data address", &INITDAT);
 	flagstr("E", "sym: entry symbol", &INITENTRY);
 	if(thearch.thechar == '5')
 		flagcount("G", "debug pseudo-ops", &debug['G']);
 	flagfn1("I", "interp: set ELF interp", setinterp);
 	flagfn1("L", "dir: add dir to library path", Lflag);
 	flagfn1("H", "head: header type", setheadtype);
 	flagcount("K", "add stack underflow checks", &debug['K']);
 	if(thearch.thechar == '5')
 		flagcount("M", "disable software div/mod", &debug['M']);
 	flagcount("O", "print pc-line tables", &debug['O']);
 	flagcount("Q", "debug byte-register code gen", &debug['Q']);
 	if(thearch.thechar == '5')
 		flagcount("P", "debug code generation", &debug['P']);
 	flagint32("R", "rnd: address rounding", &INITRND);
 	flagcount("nil", "check type signatures", &debug['S']);
 	flagint64("T", "addr: text address", &INITTEXT);
 	flagfn0("V", "print version and exit", doversion);
 	flagcount("W", "disassemble input", &debug['W']);
 	flagfn2("X", "name value: define string data", addstrdata);
 	flagcount("Z", "clear stack frame on entry", &debug['Z']);
 	flagcount("a", "disassemble output", &debug['a']);
 	flagcount("c", "dump call graph", &debug['c']);
 	flagcount("d", "disable dynamic executable", &debug['d']);
 	flagstr("extld", "ld: linker to run in external mode", &extld);
 	flagstr("extldflags", "ldflags: flags for external linker", &extldflags);
 	flagcount("f", "ignore version mismatch", &debug['f']);
 	flagcount("g", "disable go package data checks", &debug['g']);
 	flagstr("installsuffix", "suffix: pkg directory suffix", &flag_installsuffix);
 	flagstr("k", "sym: set field tracking symbol", &tracksym);
 	flagfn1("linkmode", "mode: set link mode (internal, external, auto)", setlinkmode);
 	flagcount("n", "dump symbol table", &debug['n']);
 	flagstr("o", "outfile: set output file", &outfile);
 	flagstr("r", "dir1:dir2:...: set ELF dynamic linker search path", &rpath);
 	flagcount("race", "enable race detector", &flag_race);
 	flagcount("s", "disable symbol table", &debug['s']);
 	if(thearch.thechar == '5' || thearch.thechar == '6')
 		flagcount("shared", "generate shared object (implies -linkmode external)", &flag_shared);
 	flagstr("tmpdir", "dir: leave temporary files in this directory", &tmpdir);
 	flagcount("u", "reject unsafe packages", &debug['u']);
 	flagcount("v", "print link trace", &debug['v']);
 	flagcount("w", "disable DWARF generation", &debug['w']);

 	flagparse(&argc, &argv, usage);
 	ctxt->bso = &bso;
 	ctxt->debugdivmod = debug['M'];
 	ctxt->debugfloat = debug['F'];
 	ctxt->debughist = debug['O'];
 	ctxt->debugpcln = debug['O'];
 	ctxt->debugread = debug['W'];
 	ctxt->debugstack = debug['K'];
 	ctxt->debugvlog = debug['v'];

 	if(argc != 1)
 		usage();

 	if(outfile == nil) {
 		if(HEADTYPE == Hwindows)
 			outfile = smprint("%c.out.exe", thearch.thechar);
 		else
 			outfile = smprint("%c.out", thearch.thechar);
 	}
 	libinit(); // creates outfile

 	if(HEADTYPE == -1)
 		HEADTYPE = headtype(goos);
 	ctxt->headtype = HEADTYPE;
 	if(headstring == nil)
 		headstring = headstr(HEADTYPE);

 	thearch.archinit();
 	ctxt->debugfloat = debug['F'];

 	if(debug['v'])
 		Bprint(&bso, "HEADER = -H%d -T0x%llux -D0x%llux -R0x%ux\n",
 			HEADTYPE, INITTEXT, INITDAT, INITRND);
 	Bflush(&bso);

 	cbp = buf.cbuf;
 	cbc = sizeof(buf.cbuf);

 	addlibpath(ctxt, "command line", "command line", argv[0], "main");
 	loadlib();

 	if(thearch.thechar == '5') {
 		// mark some functions that are only referenced after linker code editing
 		if(debug['F'])
 			mark(linkrlookup(ctxt, "_sfloat", 0));
 		mark(linklookup(ctxt, "runtime.read_tls_fallback", 0));
 	}

 	checkgo();
 	deadcode();
 	callgraph();
 	paramspace = "SP";	/* (FP) now (SP) on output */

 	doelf();
 	if(HEADTYPE == Hdarwin)
 		domacho();
 	dostkcheck();
 	if(HEADTYPE == Hwindows)
 		dope();
 	addexport();
 	thearch.gentext();		// trampolines, call stubs, etc.
 	textaddress();
 	pclntab();
 	findfunctab();
 	symtab();
 	dodata();
 	address();
 	doweak();
 	reloc();
 	thearch.asmb();
 	undef();
 	hostlink();
 	if(debug['v']) {
 		Bprint(&bso, "%5.2f cpu time\n", cputime());
 		Bprint(&bso, "%d symbols\n", ctxt->nsymbol);
 		Bprint(&bso, "%d sizeof adr\n", sizeof(Addr));
 		Bprint(&bso, "%d sizeof prog\n", sizeof(Prog));
 		Bprint(&bso, "%lld liveness data\n", liveness);
 	}
 	Bflush(&bso);

 	errorexit();
 }
	// Inferno utils/6l/obj.c
	// http://code.google.com/p/inferno-os/source/browse/utils/6l/obj.c
	//
	// 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)
	// Portions Copyright © 2004,2006 Bruce Ellis
	// Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
	// Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
	// Portions Copyright © 2009 The Go Authors. All rights reserved.
	//
	// Permission is hereby granted, free of charge, to any person obtaining a copy
	// of this software and associated documentation files (the "Software"), to deal
	// in the Software without restriction, including without limitation the rights
	// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	// copies of the Software, and to permit persons to whom the Software is
	// furnished to do so, subject to the following conditions:
	//
	// The above copyright notice and this permission notice shall be included in
	// all copies or substantial portions of the Software.
	//
	// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	// THE SOFTWARE.

	// Reading object files.

	#define EXTERN
	#include <u.h>
	#include <libc.h>
	#include <bio.h>
	#include <link.h>
	#include "lib.h"
	#include "elf.h"
	#include "macho.h"
	#include "dwarf.h"
	#include "pe.h"
	#include <ar.h>

	char *noname = "<none>";
	char* paramspace = "FP";

	void
	ldmain(int argc, char **argv)
	{
	int i;

	ctxt = linknew(thelinkarch);
	ctxt->thechar = thearch.thechar;
	ctxt->thestring = thestring;
	ctxt->diag = diag;
	ctxt->bso = &bso;

	Binit(&bso, 1, OWRITE);
	thearch.listinit();
	memset(debug, 0, sizeof(debug));
	nerrors = 0;
	outfile = nil;
	HEADTYPE = -1;
	INITTEXT = -1;
	INITDAT = -1;
	INITRND = -1;
	INITENTRY = 0;
	linkmode = LinkAuto;

	// For testing behavior of go command when tools crash.
	// Undocumented, not in standard flag parser to avoid
	// exposing in usage message.
	for(i=1; i<argc; i++)
	if(strcmp(argv[i], "-crash_for_testing") == 0)
	(volatile int)0 = 0;

	if(thearch.thechar == '5' && ctxt->goarm == 5)
	debug['F'] = 1;

	flagcount("1", "use alternate profiling code", &debug['1']);
	if(thearch.thechar == '6')
	flagcount("8", "assume 64-bit addresses", &debug['8']);
	flagfn1("B", "info: define ELF NT_GNU_BUILD_ID note", addbuildinfo);
	flagcount("C", "check Go calls to C code", &debug['C']);
	flagint64("D", "addr: data address", &INITDAT);
	flagstr("E", "sym: entry symbol", &INITENTRY);
	if(thearch.thechar == '5')
	flagcount("G", "debug pseudo-ops", &debug['G']);
	flagfn1("I", "interp: set ELF interp", setinterp);
	flagfn1("L", "dir: add dir to library path", Lflag);
	flagfn1("H", "head: header type", setheadtype);
	flagcount("K", "add stack underflow checks", &debug['K']);
	if(thearch.thechar == '5')
	flagcount("M", "disable software div/mod", &debug['M']);
	flagcount("O", "print pc-line tables", &debug['O']);
	flagcount("Q", "debug byte-register code gen", &debug['Q']);
	if(thearch.thechar == '5')
	flagcount("P", "debug code generation", &debug['P']);
	flagint32("R", "rnd: address rounding", &INITRND);
	flagcount("nil", "check type signatures", &debug['S']);
	flagint64("T", "addr: text address", &INITTEXT);
	flagfn0("V", "print version and exit", doversion);
	flagcount("W", "disassemble input", &debug['W']);
	flagfn2("X", "name value: define string data", addstrdata);
	flagcount("Z", "clear stack frame on entry", &debug['Z']);
	flagcount("a", "disassemble output", &debug['a']);
	flagcount("c", "dump call graph", &debug['c']);
	flagcount("d", "disable dynamic executable", &debug['d']);
	flagstr("extld", "ld: linker to run in external mode", &extld);
	flagstr("extldflags", "ldflags: flags for external linker", &extldflags);
	flagcount("f", "ignore version mismatch", &debug['f']);
	flagcount("g", "disable go package data checks", &debug['g']);
	flagstr("installsuffix", "suffix: pkg directory suffix", &flag_installsuffix);
	flagstr("k", "sym: set field tracking symbol", &tracksym);
	flagfn1("linkmode", "mode: set link mode (internal, external, auto)", setlinkmode);
	flagcount("n", "dump symbol table", &debug['n']);
	flagstr("o", "outfile: set output file", &outfile);
	flagstr("r", "dir1:dir2:...: set ELF dynamic linker search path", &rpath);
	flagcount("race", "enable race detector", &flag_race);
	flagcount("s", "disable symbol table", &debug['s']);
	if(thearch.thechar == '5' \|\| thearch.thechar == '6')
	flagcount("shared", "generate shared object (implies -linkmode external)", &flag_shared);
	flagstr("tmpdir", "dir: leave temporary files in this directory", &tmpdir);
	flagcount("u", "reject unsafe packages", &debug['u']);
	flagcount("v", "print link trace", &debug['v']);
	flagcount("w", "disable DWARF generation", &debug['w']);

	flagparse(&argc, &argv, usage);
	ctxt->bso = &bso;
	ctxt->debugdivmod = debug['M'];
	ctxt->debugfloat = debug['F'];
	ctxt->debughist = debug['O'];
	ctxt->debugpcln = debug['O'];
	ctxt->debugread = debug['W'];
	ctxt->debugstack = debug['K'];
	ctxt->debugvlog = debug['v'];

	if(argc != 1)
	usage();

	if(outfile == nil) {
	if(HEADTYPE == Hwindows)
	outfile = smprint("%c.out.exe", thearch.thechar);
	else
	outfile = smprint("%c.out", thearch.thechar);
	}
	libinit(); // creates outfile

	if(HEADTYPE == -1)
	HEADTYPE = headtype(goos);
	ctxt->headtype = HEADTYPE;
	if(headstring == nil)
	headstring = headstr(HEADTYPE);

	thearch.archinit();
	ctxt->debugfloat = debug['F'];

	if(debug['v'])
	Bprint(&bso, "HEADER = -H%d -T0x%llux -D0x%llux -R0x%ux\n",
	HEADTYPE, INITTEXT, INITDAT, INITRND);
	Bflush(&bso);

	cbp = buf.cbuf;
	cbc = sizeof(buf.cbuf);

	addlibpath(ctxt, "command line", "command line", argv[0], "main");
	loadlib();

	if(thearch.thechar == '5') {
	// mark some functions that are only referenced after linker code editing
	if(debug['F'])
	mark(linkrlookup(ctxt, "_sfloat", 0));
	mark(linklookup(ctxt, "runtime.read_tls_fallback", 0));
	}

	checkgo();
	deadcode();
	callgraph();
	paramspace = "SP"; /* (FP) now (SP) on output */

	doelf();
	if(HEADTYPE == Hdarwin)
	domacho();
	dostkcheck();
	if(HEADTYPE == Hwindows)
	dope();
	addexport();
	thearch.gentext(); // trampolines, call stubs, etc.
	textaddress();
	pclntab();
	findfunctab();
	symtab();
	dodata();
	address();
	doweak();
	reloc();
	thearch.asmb();
	undef();
	hostlink();
	if(debug['v']) {
	Bprint(&bso, "%5.2f cpu time\n", cputime());
	Bprint(&bso, "%d symbols\n", ctxt->nsymbol);
	Bprint(&bso, "%d sizeof adr\n", sizeof(Addr));
	Bprint(&bso, "%d sizeof prog\n", sizeof(Prog));
	Bprint(&bso, "%lld liveness data\n", liveness);
	}
	Bflush(&bso);

	errorexit();
	}