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-rw-r--r--src/pkg/runtime/symtab.c454
1 files changed, 0 insertions, 454 deletions
diff --git a/src/pkg/runtime/symtab.c b/src/pkg/runtime/symtab.c
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index da4579734..000000000
--- a/src/pkg/runtime/symtab.c
+++ /dev/null
@@ -1,454 +0,0 @@
-// Copyright 2009 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.
-
-// Runtime symbol table access. Work in progress.
-// The Plan 9 symbol table is not in a particularly convenient form.
-// The routines here massage it into a more usable form; eventually
-// we'll change 6l to do this for us, but it is easier to experiment
-// here than to change 6l and all the other tools.
-//
-// The symbol table also needs to be better integrated with the type
-// strings table in the future. This is just a quick way to get started
-// and figure out exactly what we want.
-
-#include "runtime.h"
-#include "defs.h"
-#include "os.h"
-#include "arch.h"
-
-extern byte pclntab[], epclntab[], symtab[], esymtab[];
-
-typedef struct Sym Sym;
-struct Sym
-{
- uintptr value;
- byte symtype;
- byte *name;
-// byte *gotype;
-};
-
-// Walk over symtab, calling fn(&s) for each symbol.
-static void
-walksymtab(void (*fn)(Sym*))
-{
- byte *p, *ep, *q;
- Sym s;
-
- p = symtab;
- ep = esymtab;
- while(p < ep) {
- if(p + 7 > ep)
- break;
- s.value = ((uint32)p[0]<<24) | ((uint32)p[1]<<16) | ((uint32)p[2]<<8) | ((uint32)p[3]);
-
- if(!(p[4]&0x80))
- break;
- s.symtype = p[4] & ~0x80;
- p += 5;
- s.name = p;
- if(s.symtype == 'z' || s.symtype == 'Z') {
- // path reference string - skip first byte,
- // then 2-byte pairs ending at two zeros.
- q = p+1;
- for(;;) {
- if(q+2 > ep)
- return;
- if(q[0] == '\0' && q[1] == '\0')
- break;
- q += 2;
- }
- p = q+2;
- }else{
- q = runtime·mchr(p, '\0', ep);
- if(q == nil)
- break;
- p = q+1;
- }
- p += 4; // go type
- fn(&s);
- }
-}
-
-// Symtab walker; accumulates info about functions.
-
-static Func *func;
-static int32 nfunc;
-
-static byte **fname;
-static int32 nfname;
-
-static Lock funclock;
-
-static void
-dofunc(Sym *sym)
-{
- Func *f;
-
- switch(sym->symtype) {
- case 't':
- case 'T':
- case 'l':
- case 'L':
- if(runtime·strcmp(sym->name, (byte*)"etext") == 0)
- break;
- if(func == nil) {
- nfunc++;
- break;
- }
- f = &func[nfunc++];
- f->name = runtime·gostringnocopy(sym->name);
- f->entry = sym->value;
- if(sym->symtype == 'L' || sym->symtype == 'l')
- f->frame = -sizeof(uintptr);
- break;
- case 'm':
- if(nfunc > 0 && func != nil)
- func[nfunc-1].frame += sym->value;
- break;
- case 'p':
- if(nfunc > 0 && func != nil) {
- f = &func[nfunc-1];
- // args counts 32-bit words.
- // sym->value is the arg's offset.
- // don't know width of this arg, so assume it is 64 bits.
- if(f->args < sym->value/4 + 2)
- f->args = sym->value/4 + 2;
- }
- break;
- case 'f':
- if(fname == nil) {
- if(sym->value >= nfname) {
- if(sym->value >= 0x10000) {
- runtime·printf("invalid symbol file index %p\n", sym->value);
- runtime·throw("mangled symbol table");
- }
- nfname = sym->value+1;
- }
- break;
- }
- fname[sym->value] = sym->name;
- break;
- }
-}
-
-// put together the path name for a z entry.
-// the f entries have been accumulated into fname already.
-static void
-makepath(byte *buf, int32 nbuf, byte *path)
-{
- int32 n, len;
- byte *p, *ep, *q;
-
- if(nbuf <= 0)
- return;
-
- p = buf;
- ep = buf + nbuf;
- *p = '\0';
- for(;;) {
- if(path[0] == 0 && path[1] == 0)
- break;
- n = (path[0]<<8) | path[1];
- path += 2;
- if(n >= nfname)
- break;
- q = fname[n];
- len = runtime·findnull(q);
- if(p+1+len >= ep)
- break;
- if(p > buf && p[-1] != '/')
- *p++ = '/';
- runtime·mcpy(p, q, len+1);
- p += len;
- }
-}
-
-// walk symtab accumulating path names for use by pc/ln table.
-// don't need the full generality of the z entry history stack because
-// there are no includes in go (and only sensible includes in our c);
-// assume code only appear in top-level files.
-static void
-dosrcline(Sym *sym)
-{
- static byte srcbuf[1000];
- static struct {
- String srcstring;
- int32 aline;
- int32 delta;
- } files[200];
- static int32 incstart;
- static int32 nfunc, nfile, nhist;
- Func *f;
- int32 i;
-
- switch(sym->symtype) {
- case 't':
- case 'T':
- if(runtime·strcmp(sym->name, (byte*)"etext") == 0)
- break;
- f = &func[nfunc++];
- // find source file
- for(i = 0; i < nfile - 1; i++) {
- if (files[i+1].aline > f->ln0)
- break;
- }
- f->src = files[i].srcstring;
- f->ln0 -= files[i].delta;
- break;
- case 'z':
- if(sym->value == 1) {
- // entry for main source file for a new object.
- makepath(srcbuf, sizeof srcbuf, sym->name+1);
- nhist = 0;
- nfile = 0;
- if(nfile == nelem(files))
- return;
- files[nfile].srcstring = runtime·gostring(srcbuf);
- files[nfile].aline = 0;
- files[nfile++].delta = 0;
- } else {
- // push or pop of included file.
- makepath(srcbuf, sizeof srcbuf, sym->name+1);
- if(srcbuf[0] != '\0') {
- if(nhist++ == 0)
- incstart = sym->value;
- if(nhist == 0 && nfile < nelem(files)) {
- // new top-level file
- files[nfile].srcstring = runtime·gostring(srcbuf);
- files[nfile].aline = sym->value;
- // this is "line 0"
- files[nfile++].delta = sym->value - 1;
- }
- }else{
- if(--nhist == 0)
- files[nfile-1].delta += sym->value - incstart;
- }
- }
- }
-}
-
-// Interpret pc/ln table, saving the subpiece for each func.
-static void
-splitpcln(void)
-{
- int32 line;
- uintptr pc;
- byte *p, *ep;
- Func *f, *ef;
- int32 pcquant;
-
- if(pclntab == epclntab || nfunc == 0)
- return;
-
- switch(thechar) {
- case '5':
- pcquant = 4;
- break;
- default: // 6, 8
- pcquant = 1;
- break;
- }
-
- // pc/ln table bounds
- p = pclntab;
- ep = epclntab;
-
- f = func;
- ef = func + nfunc;
- pc = func[0].entry; // text base
- f->pcln.array = p;
- f->pc0 = pc;
- line = 0;
- for(;;) {
- while(p < ep && *p > 128)
- pc += pcquant * (*p++ - 128);
- // runtime·printf("pc<%p targetpc=%p line=%d\n", pc, targetpc, line);
- if(*p == 0) {
- if(p+5 > ep)
- break;
- // 4 byte add to line
- line += (p[1]<<24) | (p[2]<<16) | (p[3]<<8) | p[4];
- p += 5;
- } else if(*p <= 64)
- line += *p++;
- else
- line -= *p++ - 64;
-
- // pc, line now match.
- // Because the state machine begins at pc==entry and line==0,
- // it can happen - just at the beginning! - that the update may
- // have updated line but left pc alone, to tell us the true line
- // number for pc==entry. In that case, update f->ln0.
- // Having the correct initial line number is important for choosing
- // the correct file in dosrcline above.
- if(f == func && pc == f->pc0) {
- f->pcln.array = p;
- f->pc0 = pc + pcquant;
- f->ln0 = line;
- }
-
- if(f < ef && pc >= (f+1)->entry) {
- f->pcln.len = p - f->pcln.array;
- f->pcln.cap = f->pcln.len;
- do
- f++;
- while(f < ef && pc >= (f+1)->entry);
- f->pcln.array = p;
- // pc0 and ln0 are the starting values for
- // the loop over f->pcln, so pc must be
- // adjusted by the same pcquant update
- // that we're going to do as we continue our loop.
- f->pc0 = pc + pcquant;
- f->ln0 = line;
- }
-
- pc += pcquant;
- }
- if(f < ef) {
- f->pcln.len = p - f->pcln.array;
- f->pcln.cap = f->pcln.len;
- }
-}
-
-
-// Return actual file line number for targetpc in func f.
-// (Source file is f->src.)
-// NOTE(rsc): If you edit this function, also edit extern.go:/FileLine
-int32
-runtime·funcline(Func *f, uintptr targetpc)
-{
- byte *p, *ep;
- uintptr pc;
- int32 line;
- int32 pcquant;
-
- enum {
- debug = 0
- };
-
- switch(thechar) {
- case '5':
- pcquant = 4;
- break;
- default: // 6, 8
- pcquant = 1;
- break;
- }
-
- p = f->pcln.array;
- ep = p + f->pcln.len;
- pc = f->pc0;
- line = f->ln0;
- if(debug && !runtime·panicking)
- runtime·printf("funcline start pc=%p targetpc=%p line=%d tab=%p+%d\n",
- pc, targetpc, line, p, (int32)f->pcln.len);
- for(;;) {
- // Table is a sequence of updates.
-
- // Each update says first how to adjust the pc,
- // in possibly multiple instructions...
- while(p < ep && *p > 128)
- pc += pcquant * (*p++ - 128);
-
- if(debug && !runtime·panicking)
- runtime·printf("pc<%p targetpc=%p line=%d\n", pc, targetpc, line);
-
- // If the pc has advanced too far or we're out of data,
- // stop and the last known line number.
- if(pc > targetpc || p >= ep)
- break;
-
- // ... and then how to adjust the line number,
- // in a single instruction.
- if(*p == 0) {
- if(p+5 > ep)
- break;
- line += (p[1]<<24) | (p[2]<<16) | (p[3]<<8) | p[4];
- p += 5;
- } else if(*p <= 64)
- line += *p++;
- else
- line -= *p++ - 64;
- // Now pc, line pair is consistent.
- if(debug && !runtime·panicking)
- runtime·printf("pc=%p targetpc=%p line=%d\n", pc, targetpc, line);
-
- // PC increments implicitly on each iteration.
- pc += pcquant;
- }
- return line;
-}
-
-static void
-buildfuncs(void)
-{
- extern byte etext[];
-
- if(func != nil)
- return;
-
- // Memory profiling uses this code;
- // can deadlock if the profiler ends
- // up back here.
- m->nomemprof++;
-
- // count funcs, fnames
- nfunc = 0;
- nfname = 0;
- walksymtab(dofunc);
-
- // initialize tables
- func = runtime·mal((nfunc+1)*sizeof func[0]);
- func[nfunc].entry = (uint64)etext;
- fname = runtime·mal(nfname*sizeof fname[0]);
- nfunc = 0;
- walksymtab(dofunc);
-
- // split pc/ln table by func
- splitpcln();
-
- // record src file and line info for each func
- walksymtab(dosrcline);
-
- m->nomemprof--;
-}
-
-Func*
-runtime·findfunc(uintptr addr)
-{
- Func *f;
- int32 nf, n;
-
- runtime·lock(&funclock);
- if(func == nil)
- buildfuncs();
- runtime·unlock(&funclock);
-
- if(nfunc == 0)
- return nil;
- if(addr < func[0].entry || addr >= func[nfunc].entry)
- return nil;
-
- // binary search to find func with entry <= addr.
- f = func;
- nf = nfunc;
- while(nf > 0) {
- n = nf/2;
- if(f[n].entry <= addr && addr < f[n+1].entry)
- return &f[n];
- else if(addr < f[n].entry)
- nf = n;
- else {
- f += n+1;
- nf -= n+1;
- }
- }
-
- // can't get here -- we already checked above
- // that the address was in the table bounds.
- // this can only happen if the table isn't sorted
- // by address or if the binary search above is buggy.
- runtime·prints("findfunc unreachable\n");
- return nil;
-}
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