blob: 1d5c1aad2515977deb284600cd34ecac70ae9def [file] [log] [blame]
// 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.
#include <u.h>
#include <libc.h>
#include "go.h"
#include "md5.h"
#include "y.tab.h"
#include "yerr.h"
typedef struct Error Error;
struct Error
{
int lineno;
int seq;
char *msg;
};
static Error *err;
static int nerr;
static int merr;
void
errorexit(void)
{
flusherrors();
if(outfile)
remove(outfile);
exits("error");
}
extern int yychar;
int
parserline(void)
{
if(yychar != 0 && yychar != -2) // parser has one symbol lookahead
return prevlineno;
return lineno;
}
static void
adderr(int line, char *fmt, va_list arg)
{
Fmt f;
Error *p;
fmtstrinit(&f);
fmtprint(&f, "%L: ", line);
fmtvprint(&f, fmt, arg);
fmtprint(&f, "\n");
if(nerr >= merr) {
if(merr == 0)
merr = 16;
else
merr *= 2;
p = realloc(err, merr*sizeof err[0]);
if(p == nil) {
merr = nerr;
flusherrors();
print("out of memory\n");
errorexit();
}
err = p;
}
err[nerr].seq = nerr;
err[nerr].lineno = line;
err[nerr].msg = fmtstrflush(&f);
nerr++;
}
static int
errcmp(const void *va, const void *vb)
{
Error *a, *b;
a = (Error*)va;
b = (Error*)vb;
if(a->lineno != b->lineno)
return a->lineno - b->lineno;
if(a->seq != b->seq)
return a->seq - b->seq;
return strcmp(a->msg, b->msg);
}
void
flusherrors(void)
{
int i;
if(nerr == 0)
return;
qsort(err, nerr, sizeof err[0], errcmp);
for(i=0; i<nerr; i++)
if(i==0 || strcmp(err[i].msg, err[i-1].msg) != 0)
print("%s", err[i].msg);
nerr = 0;
}
static void
hcrash(void)
{
if(debug['h']) {
flusherrors();
if(outfile)
remove(outfile);
*(volatile int*)0 = 0;
}
}
void
yyerrorl(int line, char *fmt, ...)
{
va_list arg;
va_start(arg, fmt);
adderr(line, fmt, arg);
va_end(arg);
hcrash();
nerrors++;
if(nerrors >= 10 && !debug['e']) {
flusherrors();
print("%L: too many errors\n", line);
errorexit();
}
}
extern int yystate, yychar;
void
yyerror(char *fmt, ...)
{
int i;
static int lastsyntax;
va_list arg;
char buf[512], *p;
if(strncmp(fmt, "syntax error", 12) == 0) {
nsyntaxerrors++;
if(debug['x'])
print("yyerror: yystate=%d yychar=%d\n", yystate, yychar);
// only one syntax error per line
if(lastsyntax == lexlineno)
return;
lastsyntax = lexlineno;
if(strstr(fmt, "{ or {")) {
// The grammar has { and LBRACE but both show up as {.
// Rewrite syntax error referring to "{ or {" to say just "{".
strecpy(buf, buf+sizeof buf, fmt);
p = strstr(buf, "{ or {");
if(p)
memmove(p+1, p+6, strlen(p+6)+1);
fmt = buf;
}
// look for parse state-specific errors in list (see go.errors).
for(i=0; i<nelem(yymsg); i++) {
if(yymsg[i].yystate == yystate && yymsg[i].yychar == yychar) {
yyerrorl(lexlineno, "syntax error: %s", yymsg[i].msg);
return;
}
}
// plain "syntax error" gets "near foo" added
if(strcmp(fmt, "syntax error") == 0) {
yyerrorl(lexlineno, "syntax error near %s", lexbuf);
return;
}
// if bison says "syntax error, more info"; print "syntax error: more info".
if(fmt[12] == ',') {
yyerrorl(lexlineno, "syntax error:%s", fmt+13);
return;
}
yyerrorl(lexlineno, "%s", fmt);
return;
}
va_start(arg, fmt);
adderr(parserline(), fmt, arg);
va_end(arg);
hcrash();
nerrors++;
if(nerrors >= 10 && !debug['e']) {
flusherrors();
print("%L: too many errors\n", parserline());
errorexit();
}
}
void
warn(char *fmt, ...)
{
va_list arg;
va_start(arg, fmt);
adderr(parserline(), fmt, arg);
va_end(arg);
hcrash();
}
void
warnl(int line, char *fmt, ...)
{
va_list arg;
va_start(arg, fmt);
adderr(line, fmt, arg);
va_end(arg);
}
void
fatal(char *fmt, ...)
{
va_list arg;
flusherrors();
print("%L: internal compiler error: ", lineno);
va_start(arg, fmt);
vfprint(1, fmt, arg);
va_end(arg);
print("\n");
// If this is a released compiler version, ask for a bug report.
if(strncmp(getgoversion(), "release", 7) == 0) {
print("\n");
print("Please file a bug report including a short program that triggers the error.\n");
print("http://code.google.com/p/go/issues/entry?template=compilerbug\n");
}
hcrash();
errorexit();
}
void
linehist(char *file, int32 off, int relative)
{
Hist *h;
char *cp;
if(debug['i']) {
if(file != nil) {
if(off < 0)
print("pragma %s", file);
else
if(off > 0)
print("line %s", file);
else
print("import %s", file);
} else
print("end of import");
print(" at line %L\n", lexlineno);
}
if(off < 0 && file[0] != '/' && !relative) {
cp = mal(strlen(file) + strlen(pathname) + 2);
sprint(cp, "%s/%s", pathname, file);
file = cp;
}
h = mal(sizeof(Hist));
h->name = file;
h->line = lexlineno;
h->offset = off;
h->link = H;
if(ehist == H) {
hist = h;
ehist = h;
return;
}
ehist->link = h;
ehist = h;
}
int32
setlineno(Node *n)
{
int32 lno;
lno = lineno;
if(n != N)
switch(n->op) {
case ONAME:
case OTYPE:
case OPACK:
case OLITERAL:
break;
default:
lineno = n->lineno;
if(lineno == 0) {
if(debug['K'])
warn("setlineno: line 0");
lineno = lno;
}
}
return lno;
}
uint32
stringhash(char *p)
{
int32 h;
int c;
h = 0;
for(;;) {
c = *p++;
if(c == 0)
break;
h = h*PRIME1 + c;
}
if(h < 0) {
h = -h;
if(h < 0)
h = 0;
}
return h;
}
Sym*
lookup(char *name)
{
return pkglookup(name, localpkg);
}
Sym*
pkglookup(char *name, Pkg *pkg)
{
Sym *s;
uint32 h;
int c;
h = stringhash(name) % NHASH;
c = name[0];
for(s = hash[h]; s != S; s = s->link) {
if(s->name[0] != c || s->pkg != pkg)
continue;
if(strcmp(s->name, name) == 0)
return s;
}
s = mal(sizeof(*s));
s->name = mal(strlen(name)+1);
strcpy(s->name, name);
s->pkg = pkg;
s->link = hash[h];
hash[h] = s;
s->lexical = LNAME;
return s;
}
Sym*
restrictlookup(char *name, Pkg *pkg)
{
if(!exportname(name) && pkg != localpkg)
yyerror("cannot refer to unexported name %s.%s", pkg->name, name);
return pkglookup(name, pkg);
}
// find all the exported symbols in package opkg
// and make them available in the current package
void
importdot(Pkg *opkg, Node *pack)
{
Sym *s, *s1;
uint32 h;
int n;
n = 0;
for(h=0; h<NHASH; h++) {
for(s = hash[h]; s != S; s = s->link) {
if(s->pkg != opkg)
continue;
if(s->def == N)
continue;
if(!exportname(s->name) || utfrune(s->name, 0xb7)) // 0xb7 = center dot
continue;
s1 = lookup(s->name);
if(s1->def != N) {
redeclare(s1, "during import");
continue;
}
s1->def = s->def;
s1->block = s->block;
s1->def->pack = pack;
n++;
}
}
if(n == 0) {
// can't possibly be used - there were no symbols
yyerrorl(pack->lineno, "imported and not used: \"%Z\"", opkg->path);
}
}
static void
gethunk(void)
{
char *h;
int32 nh;
nh = NHUNK;
if(thunk >= 10L*NHUNK)
nh = 10L*NHUNK;
h = (char*)malloc(nh);
if(h == nil) {
flusherrors();
yyerror("out of memory");
errorexit();
}
hunk = h;
nhunk = nh;
thunk += nh;
}
void*
mal(int32 n)
{
void *p;
if(n >= NHUNK) {
p = malloc(n);
if(p == nil) {
flusherrors();
yyerror("out of memory");
errorexit();
}
memset(p, 0, n);
return p;
}
while((uintptr)hunk & MAXALIGN) {
hunk++;
nhunk--;
}
if(nhunk < n)
gethunk();
p = hunk;
nhunk -= n;
hunk += n;
memset(p, 0, n);
return p;
}
void*
remal(void *p, int32 on, int32 n)
{
void *q;
q = (uchar*)p + on;
if(q != hunk || nhunk < n) {
if(on+n >= NHUNK) {
q = mal(on+n);
memmove(q, p, on);
return q;
}
if(nhunk < on+n)
gethunk();
memmove(hunk, p, on);
p = hunk;
hunk += on;
nhunk -= on;
}
hunk += n;
nhunk -= n;
return p;
}
Node*
nod(int op, Node *nleft, Node *nright)
{
Node *n;
n = mal(sizeof(*n));
n->op = op;
n->left = nleft;
n->right = nright;
n->lineno = parserline();
n->xoffset = BADWIDTH;
n->orig = n;
n->curfn = curfn;
return n;
}
int
algtype(Type *t)
{
int a;
if(issimple[t->etype] || isptr[t->etype] ||
t->etype == TCHAN || t->etype == TFUNC || t->etype == TMAP) {
if(t->width == 1)
a = AMEM8;
else if(t->width == 2)
a = AMEM16;
else if(t->width == 4)
a = AMEM32;
else if(t->width == 8)
a = AMEM64;
else if(t->width == 16)
a = AMEM128;
else
a = AMEM; // just bytes (int, ptr, etc)
} else if(t->etype == TSTRING)
a = ASTRING; // string
else if(isnilinter(t))
a = ANILINTER; // nil interface
else if(t->etype == TINTER)
a = AINTER; // interface
else if(isslice(t))
a = ASLICE; // slice
else {
if(t->width == 1)
a = ANOEQ8;
else if(t->width == 2)
a = ANOEQ16;
else if(t->width == 4)
a = ANOEQ32;
else if(t->width == 8)
a = ANOEQ64;
else if(t->width == 16)
a = ANOEQ128;
else
a = ANOEQ; // just bytes, but no hash/eq
}
return a;
}
Type*
maptype(Type *key, Type *val)
{
Type *t;
if(key != nil) {
switch(key->etype) {
case TARRAY:
case TSTRUCT:
yyerror("invalid map key type %T", key);
break;
case TFORW:
// map[key] used during definition of key.
// postpone check until key is fully defined.
// if there are multiple uses of map[key]
// before key is fully defined, the error
// will only be printed for the first one.
// good enough.
if(key->maplineno == 0)
key->maplineno = lineno;
break;
}
}
t = typ(TMAP);
t->down = key;
t->type = val;
return t;
}
Type*
typ(int et)
{
Type *t;
t = mal(sizeof(*t));
t->etype = et;
t->width = BADWIDTH;
t->lineno = lineno;
t->orig = t;
return t;
}
static int
methcmp(const void *va, const void *vb)
{
Type *a, *b;
int i;
a = *(Type**)va;
b = *(Type**)vb;
i = strcmp(a->sym->name, b->sym->name);
if(i != 0)
return i;
if(!exportname(a->sym->name)) {
i = strcmp(a->sym->pkg->path->s, b->sym->pkg->path->s);
if(i != 0)
return i;
}
return 0;
}
Type*
sortinter(Type *t)
{
Type *f;
int i;
Type **a;
if(t->type == nil || t->type->down == nil)
return t;
i=0;
for(f=t->type; f; f=f->down)
i++;
a = mal(i*sizeof f);
i = 0;
for(f=t->type; f; f=f->down)
a[i++] = f;
qsort(a, i, sizeof a[0], methcmp);
while(i-- > 0) {
a[i]->down = f;
f = a[i];
}
t->type = f;
return t;
}
Node*
nodintconst(int64 v)
{
Node *c;
c = nod(OLITERAL, N, N);
c->addable = 1;
c->val.u.xval = mal(sizeof(*c->val.u.xval));
mpmovecfix(c->val.u.xval, v);
c->val.ctype = CTINT;
c->type = types[TIDEAL];
ullmancalc(c);
return c;
}
Node*
nodfltconst(Mpflt* v)
{
Node *c;
c = nod(OLITERAL, N, N);
c->addable = 1;
c->val.u.fval = mal(sizeof(*c->val.u.fval));
mpmovefltflt(c->val.u.fval, v);
c->val.ctype = CTFLT;
c->type = types[TIDEAL];
ullmancalc(c);
return c;
}
void
nodconst(Node *n, Type *t, int64 v)
{
memset(n, 0, sizeof(*n));
n->op = OLITERAL;
n->addable = 1;
ullmancalc(n);
n->val.u.xval = mal(sizeof(*n->val.u.xval));
mpmovecfix(n->val.u.xval, v);
n->val.ctype = CTINT;
n->type = t;
if(isfloat[t->etype])
fatal("nodconst: bad type %T", t);
}
Node*
nodnil(void)
{
Node *c;
c = nodintconst(0);
c->val.ctype = CTNIL;
c->type = types[TNIL];
return c;
}
Node*
nodbool(int b)
{
Node *c;
c = nodintconst(0);
c->val.ctype = CTBOOL;
c->val.u.bval = b;
c->type = idealbool;
return c;
}
Type*
aindex(Node *b, Type *t)
{
Type *r;
int bound;
bound = -1; // open bound
typecheck(&b, Erv);
if(b != nil) {
switch(consttype(b)) {
default:
yyerror("array bound must be an integer expression");
break;
case CTINT:
bound = mpgetfix(b->val.u.xval);
if(bound < 0)
yyerror("array bound must be non negative");
break;
}
}
// fixed array
r = typ(TARRAY);
r->type = t;
r->bound = bound;
return r;
}
Node*
treecopy(Node *n)
{
Node *m;
if(n == N)
return N;
switch(n->op) {
default:
m = nod(OXXX, N, N);
*m = *n;
m->left = treecopy(n->left);
m->right = treecopy(n->right);
m->list = listtreecopy(n->list);
if(m->defn)
abort();
break;
case ONONAME:
if(n->sym == lookup("iota")) {
// Not sure yet whether this is the real iota,
// but make a copy of the Node* just in case,
// so that all the copies of this const definition
// don't have the same iota value.
m = nod(OXXX, N, N);
*m = *n;
m->iota = iota;
break;
}
// fall through
case ONAME:
case OLITERAL:
case OTYPE:
m = n;
break;
}
return m;
}
int
isnil(Node *n)
{
if(n == N)
return 0;
if(n->op != OLITERAL)
return 0;
if(n->val.ctype != CTNIL)
return 0;
return 1;
}
int
isptrto(Type *t, int et)
{
if(t == T)
return 0;
if(!isptr[t->etype])
return 0;
t = t->type;
if(t == T)
return 0;
if(t->etype != et)
return 0;
return 1;
}
int
istype(Type *t, int et)
{
return t != T && t->etype == et;
}
int
isfixedarray(Type *t)
{
return t != T && t->etype == TARRAY && t->bound >= 0;
}
int
isslice(Type *t)
{
return t != T && t->etype == TARRAY && t->bound < 0;
}
int
isblank(Node *n)
{
char *p;
if(n == N || n->sym == S)
return 0;
p = n->sym->name;
if(p == nil)
return 0;
return p[0] == '_' && p[1] == '\0';
}
int
isinter(Type *t)
{
return t != T && t->etype == TINTER;
}
int
isnilinter(Type *t)
{
if(!isinter(t))
return 0;
if(t->type != T)
return 0;
return 1;
}
int
isideal(Type *t)
{
if(t == T)
return 0;
if(t == idealstring || t == idealbool)
return 1;
switch(t->etype) {
case TNIL:
case TIDEAL:
return 1;
}
return 0;
}
/*
* given receiver of type t (t == r or t == *r)
* return type to hang methods off (r).
*/
Type*
methtype(Type *t)
{
if(t == T)
return T;
// strip away pointer if it's there
if(isptr[t->etype]) {
if(t->sym != S)
return T;
t = t->type;
if(t == T)
return T;
}
// need a type name
if(t->sym == S)
return T;
// check types
if(!issimple[t->etype])
switch(t->etype) {
default:
return T;
case TSTRUCT:
case TARRAY:
case TMAP:
case TCHAN:
case TSTRING:
case TFUNC:
break;
}
return t;
}
int
cplxsubtype(int et)
{
switch(et) {
case TCOMPLEX64:
return TFLOAT32;
case TCOMPLEX128:
return TFLOAT64;
}
fatal("cplxsubtype: %E\n", et);
return 0;
}
static int
eqnote(Strlit *a, Strlit *b)
{
if(a == b)
return 1;
if(a == nil || b == nil)
return 0;
if(a->len != b->len)
return 0;
return memcmp(a->s, b->s, a->len) == 0;
}
// Return 1 if t1 and t2 are identical, following the spec rules.
//
// Any cyclic type must go through a named type, and if one is
// named, it is only identical to the other if they are the same
// pointer (t1 == t2), so there's no chance of chasing cycles
// ad infinitum, so no need for a depth counter.
int
eqtype(Type *t1, Type *t2)
{
if(t1 == t2)
return 1;
if(t1 == T || t2 == T || t1->etype != t2->etype)
return 0;
if(t1->sym || t2->sym) {
// Special case: we keep byte and uint8 separate
// for error messages. Treat them as equal.
switch(t1->etype) {
case TUINT8:
if((t1 == types[TUINT8] || t1 == bytetype) && (t2 == types[TUINT8] || t2 == bytetype))
return 1;
break;
case TINT:
case TINT32:
if((t1 == types[runetype->etype] || t1 == runetype) && (t2 == types[runetype->etype] || t2 == runetype))
return 1;
break;
}
return 0;
}
switch(t1->etype) {
case TINTER:
case TSTRUCT:
for(t1=t1->type, t2=t2->type; t1 && t2; t1=t1->down, t2=t2->down) {
if(t1->etype != TFIELD || t2->etype != TFIELD)
fatal("struct/interface missing field: %T %T", t1, t2);
if(t1->sym != t2->sym || t1->embedded != t2->embedded || !eqtype(t1->type, t2->type) || !eqnote(t1->note, t2->note))
return 0;
}
return t1 == T && t2 == T;
case TFUNC:
// Loop over structs: receiver, in, out.
for(t1=t1->type, t2=t2->type; t1 && t2; t1=t1->down, t2=t2->down) {
Type *ta, *tb;
if(t1->etype != TSTRUCT || t2->etype != TSTRUCT)
fatal("func missing struct: %T %T", t1, t2);
// Loop over fields in structs, ignoring argument names.
for(ta=t1->type, tb=t2->type; ta && tb; ta=ta->down, tb=tb->down) {
if(ta->etype != TFIELD || tb->etype != TFIELD)
fatal("func struct missing field: %T %T", ta, tb);
if(ta->isddd != tb->isddd || !eqtype(ta->type, tb->type))
return 0;
}
if(ta != T || tb != T)
return 0;
}
return t1 == T && t2 == T;
case TARRAY:
if(t1->bound != t2->bound)
return 0;
break;
case TCHAN:
if(t1->chan != t2->chan)
return 0;
break;
}
return eqtype(t1->down, t2->down) && eqtype(t1->type, t2->type);
}
// Are t1 and t2 equal struct types when field names are ignored?
// For deciding whether the result struct from g can be copied
// directly when compiling f(g()).
int
eqtypenoname(Type *t1, Type *t2)
{
if(t1 == T || t2 == T || t1->etype != TSTRUCT || t2->etype != TSTRUCT)
return 0;
t1 = t1->type;
t2 = t2->type;
for(;;) {
if(!eqtype(t1, t2))
return 0;
if(t1 == T)
return 1;
t1 = t1->down;
t2 = t2->down;
}
}
// Is type src assignment compatible to type dst?
// If so, return op code to use in conversion.
// If not, return 0.
//
// It is the caller's responsibility to call exportassignok
// to check for assignments to other packages' unexported fields,
int
assignop(Type *src, Type *dst, char **why)
{
Type *missing, *have;
int ptr;
if(why != nil)
*why = "";
if(safemode && src != T && src->etype == TUNSAFEPTR) {
yyerror("cannot use unsafe.Pointer");
errorexit();
}
if(src == dst)
return OCONVNOP;
if(src == T || dst == T || src->etype == TFORW || dst->etype == TFORW || src->orig == T || dst->orig == T)
return 0;
// 1. src type is identical to dst.
if(eqtype(src, dst))
return OCONVNOP;
// 2. src and dst have identical underlying types
// and either src or dst is not a named type or
// both are interface types.
if(eqtype(src->orig, dst->orig) && (src->sym == S || dst->sym == S || src->etype == TINTER))
return OCONVNOP;
// 3. dst is an interface type and src implements dst.
if(dst->etype == TINTER && src->etype != TNIL) {
if(implements(src, dst, &missing, &have, &ptr))
return OCONVIFACE;
if(why != nil) {
if(isptrto(src, TINTER))
*why = smprint(":\n\t%T is pointer to interface, not interface", src);
else if(have && have->sym == missing->sym)
*why = smprint(":\n\t%T does not implement %T (wrong type for %S method)\n"
"\t\thave %S%hhT\n\t\twant %S%hhT", src, dst, missing->sym,
have->sym, have->type, missing->sym, missing->type);
else if(ptr)
*why = smprint(":\n\t%T does not implement %T (%S method requires pointer receiver)",
src, dst, missing->sym);
else if(have)
*why = smprint(":\n\t%T does not implement %T (missing %S method)\n"
"\t\thave %S%hhT\n\t\twant %S%hhT", src, dst, missing->sym,
have->sym, have->type, missing->sym, missing->type);
else
*why = smprint(":\n\t%T does not implement %T (missing %S method)",
src, dst, missing->sym);
}
return 0;
}
if(isptrto(dst, TINTER)) {
if(why != nil)
*why = smprint(":\n\t%T is pointer to interface, not interface", dst);
return 0;
}
if(src->etype == TINTER && dst->etype != TBLANK) {
if(why != nil)
*why = ": need type assertion";
return 0;
}
// 4. src is a bidirectional channel value, dst is a channel type,
// src and dst have identical element types, and
// either src or dst is not a named type.
if(src->etype == TCHAN && src->chan == Cboth && dst->etype == TCHAN)
if(eqtype(src->type, dst->type) && (src->sym == S || dst->sym == S))
return OCONVNOP;
// 5. src is the predeclared identifier nil and dst is a nillable type.
if(src->etype == TNIL) {
switch(dst->etype) {
case TARRAY:
if(dst->bound != -100) // not slice
break;
case TPTR32:
case TPTR64:
case TFUNC:
case TMAP:
case TCHAN:
case TINTER:
return OCONVNOP;
}
}
// 6. rule about untyped constants - already converted by defaultlit.
// 7. Any typed value can be assigned to the blank identifier.
if(dst->etype == TBLANK)
return OCONVNOP;
return 0;
}
// Can we convert a value of type src to a value of type dst?
// If so, return op code to use in conversion (maybe OCONVNOP).
// If not, return 0.
int
convertop(Type *src, Type *dst, char **why)
{
int op;
if(why != nil)
*why = "";
if(src == dst)
return OCONVNOP;
if(src == T || dst == T)
return 0;
// 1. src can be assigned to dst.
if((op = assignop(src, dst, why)) != 0)
return op;
// The rules for interfaces are no different in conversions
// than assignments. If interfaces are involved, stop now
// with the good message from assignop.
// Otherwise clear the error.
if(src->etype == TINTER || dst->etype == TINTER)
return 0;
if(why != nil)
*why = "";
// 2. src and dst have identical underlying types.
if(eqtype(src->orig, dst->orig))
return OCONVNOP;
// 3. src and dst are unnamed pointer types
// and their base types have identical underlying types.
if(isptr[src->etype] && isptr[dst->etype] && src->sym == S && dst->sym == S)
if(eqtype(src->type->orig, dst->type->orig))
return OCONVNOP;
// 4. src and dst are both integer or floating point types.
if((isint[src->etype] || isfloat[src->etype]) && (isint[dst->etype] || isfloat[dst->etype])) {
if(simtype[src->etype] == simtype[dst->etype])
return OCONVNOP;
return OCONV;
}
// 5. src and dst are both complex types.
if(iscomplex[src->etype] && iscomplex[dst->etype]) {
if(simtype[src->etype] == simtype[dst->etype])
return OCONVNOP;
return OCONV;
}
// 6. src is an integer or has type []byte or []rune
// and dst is a string type.
if(isint[src->etype] && dst->etype == TSTRING)
return ORUNESTR;
if(isslice(src) && src->sym == nil && dst->etype == TSTRING) {
if(eqtype(src->type, bytetype))
return OARRAYBYTESTR;
if(eqtype(src->type, runetype))
return OARRAYRUNESTR;
}
// 7. src is a string and dst is []byte or []rune.
// String to slice.
if(src->etype == TSTRING && isslice(dst) && dst->sym == nil) {
if(eqtype(dst->type, bytetype))
return OSTRARRAYBYTE;
if(eqtype(dst->type, runetype))
return OSTRARRAYRUNE;
}
// 8. src is a pointer or uintptr and dst is unsafe.Pointer.
if((isptr[src->etype] || src->etype == TUINTPTR) && dst->etype == TUNSAFEPTR)
return OCONVNOP;
// 9. src is unsafe.Pointer and dst is a pointer or uintptr.
if(src->etype == TUNSAFEPTR && (isptr[dst->etype] || dst->etype == TUINTPTR))
return OCONVNOP;
return 0;
}
// Convert node n for assignment to type t.
Node*
assignconv(Node *n, Type *t, char *context)
{
int op;
Node *r, *old;
char *why;
if(n == N || n->type == T)
return n;
old = n;
old->diag++; // silence errors about n; we'll issue one below
defaultlit(&n, t);
old->diag--;
if(t->etype == TBLANK)
return n;
exportassignok(n->type, context);
if(eqtype(n->type, t))
return n;
op = assignop(n->type, t, &why);
if(op == 0) {
yyerror("cannot use %lN as type %T in %s%s", n, t, context, why);
op = OCONV;
}
r = nod(op, n, N);
r->type = t;
r->typecheck = 1;
r->implicit = 1;
return r;
}
static int
subtype(Type **stp, Type *t, int d)
{
Type *st;
loop:
st = *stp;
if(st == T)
return 0;
d++;
if(d >= 10)
return 0;
switch(st->etype) {
default:
return 0;
case TPTR32:
case TPTR64:
case TCHAN:
case TARRAY:
stp = &st->type;
goto loop;
case TANY:
if(!st->copyany)
return 0;
*stp = t;
break;
case TMAP:
if(subtype(&st->down, t, d))
break;
stp = &st->type;
goto loop;
case TFUNC:
for(;;) {
if(subtype(&st->type, t, d))
break;
if(subtype(&st->type->down->down, t, d))
break;
if(subtype(&st->type->down, t, d))
break;
return 0;
}
break;
case TSTRUCT:
for(st=st->type; st!=T; st=st->down)
if(subtype(&st->type, t, d))
return 1;
return 0;
}
return 1;
}
/*
* Is this a 64-bit type?
*/
int
is64(Type *t)
{
if(t == T)
return 0;
switch(simtype[t->etype]) {
case TINT64:
case TUINT64:
case TPTR64:
return 1;
}
return 0;
}
/*
* Is a conversion between t1 and t2 a no-op?
*/
int
noconv(Type *t1, Type *t2)
{
int e1, e2;
e1 = simtype[t1->etype];
e2 = simtype[t2->etype];
switch(e1) {
case TINT8:
case TUINT8:
return e2 == TINT8 || e2 == TUINT8;
case TINT16:
case TUINT16:
return e2 == TINT16 || e2 == TUINT16;
case TINT32:
case TUINT32:
case TPTR32:
return e2 == TINT32 || e2 == TUINT32 || e2 == TPTR32;
case TINT64:
case TUINT64:
case TPTR64:
return e2 == TINT64 || e2 == TUINT64 || e2 == TPTR64;
case TFLOAT32:
return e2 == TFLOAT32;
case TFLOAT64:
return e2 == TFLOAT64;
}
return 0;
}
void
argtype(Node *on, Type *t)
{
dowidth(t);
if(!subtype(&on->type, t, 0))
fatal("argtype: failed %N %T\n", on, t);
}
Type*
shallow(Type *t)
{
Type *nt;
if(t == T)
return T;
nt = typ(0);
*nt = *t;
if(t->orig == t)
nt->orig = nt;
return nt;
}
static Type*
deep(Type *t)
{
Type *nt, *xt;
if(t == T)
return T;
switch(t->etype) {
default:
nt = t; // share from here down
break;
case TANY:
nt = shallow(t);
nt->copyany = 1;
break;
case TPTR32:
case TPTR64:
case TCHAN:
case TARRAY:
nt = shallow(t);
nt->type = deep(t->type);
break;
case TMAP:
nt = shallow(t);
nt->down = deep(t->down);
nt->type = deep(t->type);
break;
case TFUNC:
nt = shallow(t);
nt->type = deep(t->type);
nt->type->down = deep(t->type->down);
nt->type->down->down = deep(t->type->down->down);
break;
case TSTRUCT:
nt = shallow(t);
nt->type = shallow(t->type);
xt = nt->type;
for(t=t->type; t!=T; t=t->down) {
xt->type = deep(t->type);
xt->down = shallow(t->down);
xt = xt->down;
}
break;
}
return nt;
}
Node*
syslook(char *name, int copy)
{
Sym *s;
Node *n;
s = pkglookup(name, runtimepkg);
if(s == S || s->def == N)
fatal("syslook: can't find runtime.%s", name);
if(!copy)
return s->def;
n = nod(0, N, N);
*n = *s->def;
n->type = deep(s->def->type);
return n;
}
/*
* compute a hash value for type t.
* if t is a method type, ignore the receiver
* so that the hash can be used in interface checks.
* %T already contains
* all the necessary logic to generate a representation
* of the type that completely describes it.
* using smprint here avoids duplicating that code.
* using md5 here is overkill, but i got tired of
* accidental collisions making the runtime think
* two types are equal when they really aren't.
*/
uint32
typehash(Type *t)
{
char *p;
MD5 d;
if(t->thistuple) {
// hide method receiver from Tpretty
t->thistuple = 0;
p = smprint("%-uT", t);
t->thistuple = 1;
} else
p = smprint("%-uT", t);
//print("typehash: %s\n", p);
md5reset(&d);
md5write(&d, (uchar*)p, strlen(p));
free(p);
return md5sum(&d);
}
Type*
ptrto(Type *t)
{
Type *t1;
if(tptr == 0)
fatal("ptrto: no tptr");
t1 = typ(tptr);
t1->type = t;
t1->width = widthptr;
t1->align = widthptr;
return t1;
}
void
frame(int context)
{
char *p;
NodeList *l;
Node *n;
int flag;
p = "stack";
l = nil;
if(curfn)
l = curfn->dcl;
if(context) {
p = "external";
l = externdcl;
}
flag = 1;
for(; l; l=l->next) {
n = l->n;
switch(n->op) {
case ONAME:
if(flag)
print("--- %s frame ---\n", p);
print("%O %S G%d %T\n", n->op, n->sym, n->vargen, n->type);
flag = 0;
break;
case OTYPE:
if(flag)
print("--- %s frame ---\n", p);
print("%O %T\n", n->op, n->type);
flag = 0;
break;
}
}
}
/*
* calculate sethi/ullman number
* roughly how many registers needed to
* compile a node. used to compile the
* hardest side first to minimize registers.
*/
void
ullmancalc(Node *n)
{
int ul, ur;
if(n == N)
return;
switch(n->op) {
case OREGISTER:
case OLITERAL:
case ONAME:
ul = 1;
if(n->class == PPARAMREF || (n->class & PHEAP))
ul++;
goto out;
case OCALL:
case OCALLFUNC:
case OCALLMETH:
case OCALLINTER:
ul = UINF;
goto out;
}
ul = 1;
if(n->left != N)
ul = n->left->ullman;
ur = 1;
if(n->right != N)
ur = n->right->ullman;
if(ul == ur)
ul += 1;
if(ur > ul)
ul = ur;
out:
n->ullman = ul;
}
void
badtype(int o, Type *tl, Type *tr)
{
Fmt fmt;
char *s;
fmtstrinit(&fmt);
if(tl != T)
fmtprint(&fmt, "\n %T", tl);
if(tr != T)
fmtprint(&fmt, "\n %T", tr);
// common mistake: *struct and *interface.
if(tl && tr && isptr[tl->etype] && isptr[tr->etype]) {
if(tl->type->etype == TSTRUCT && tr->type->etype == TINTER)
fmtprint(&fmt, "\n (*struct vs *interface)");
else if(tl->type->etype == TINTER && tr->type->etype == TSTRUCT)
fmtprint(&fmt, "\n (*interface vs *struct)");
}
s = fmtstrflush(&fmt);
yyerror("illegal types for operand: %O%s", o, s);
}
/*
* iterator to walk a structure declaration
*/
Type*
structfirst(Iter *s, Type **nn)
{
Type *n, *t;
n = *nn;
if(n == T)
goto bad;
switch(n->etype) {
default:
goto bad;
case TSTRUCT:
case TINTER:
case TFUNC:
break;
}
t = n->type;
if(t == T)
goto rnil;
if(t->etype != TFIELD)
fatal("structfirst: not field %T", t);
s->t = t;
return t;
bad:
fatal("structfirst: not struct %T", n);
rnil:
return T;
}
Type*
structnext(Iter *s)
{
Type *n, *t;
n = s->t;
t = n->down;
if(t == T)
goto rnil;
if(t->etype != TFIELD)
goto bad;
s->t = t;
return t;
bad:
fatal("structnext: not struct %T", n);
rnil:
return T;
}
/*
* iterator to this and inargs in a function
*/
Type*
funcfirst(Iter *s, Type *t)
{
Type *fp;
if(t == T)
goto bad;
if(t->etype != TFUNC)
goto bad;
s->tfunc = t;
s->done = 0;
fp = structfirst(s, getthis(t));
if(fp == T) {
s->done = 1;
fp = structfirst(s, getinarg(t));
}
return fp;
bad:
fatal("funcfirst: not func %T", t);
return T;
}
Type*
funcnext(Iter *s)
{
Type *fp;
fp = structnext(s);
if(fp == T && !s->done) {
s->done = 1;
fp = structfirst(s, getinarg(s->tfunc));
}
return fp;
}
Type**
getthis(Type *t)
{
if(t->etype != TFUNC)
fatal("getthis: not a func %T", t);
return &t->type;
}
Type**
getoutarg(Type *t)
{
if(t->etype != TFUNC)
fatal("getoutarg: not a func %T", t);
return &t->type->down;
}
Type**
getinarg(Type *t)
{
if(t->etype != TFUNC)
fatal("getinarg: not a func %T", t);
return &t->type->down->down;
}
Type*
getthisx(Type *t)
{
return *getthis(t);
}
Type*
getoutargx(Type *t)
{
return *getoutarg(t);
}
Type*
getinargx(Type *t)
{
return *getinarg(t);
}
/*
* return !(op)
* eg == <=> !=
*/
int
brcom(int a)
{
switch(a) {
case OEQ: return ONE;
case ONE: return OEQ;
case OLT: return OGE;
case OGT: return OLE;
case OLE: return OGT;
case OGE: return OLT;
}
fatal("brcom: no com for %A\n", a);
return a;
}
/*
* return reverse(op)
* eg a op b <=> b r(op) a
*/
int
brrev(int a)
{
switch(a) {
case OEQ: return OEQ;
case ONE: return ONE;
case OLT: return OGT;
case OGT: return OLT;
case OLE: return OGE;
case OGE: return OLE;
}
fatal("brcom: no rev for %A\n", a);
return a;
}
/*
* return side effect-free n, appending side effects to init.
* result is assignable if n is.
*/
Node*
safeexpr(Node *n, NodeList **init)
{
Node *l;
Node *r;
Node *a;
if(n == N)
return N;
switch(n->op) {
case ONAME:
case OLITERAL:
return n;
case ODOT:
l = safeexpr(n->left, init);
if(l == n->left)
return n;
r = nod(OXXX, N, N);
*r = *n;
r->left = l;
typecheck(&r, Erv);
walkexpr(&r, init);
return r;
case ODOTPTR:
case OIND:
l = safeexpr(n->left, init);
if(l == n->left)
return n;
a = nod(OXXX, N, N);
*a = *n;
a->left = l;
walkexpr(&a, init);
return a;
case OINDEX:
case OINDEXMAP:
l = safeexpr(n->left, init);
r = safeexpr(n->right, init);
if(l == n->left && r == n->right)
return n;
a = nod(OXXX, N, N);
*a = *n;
a->left = l;
a->right = r;
walkexpr(&a, init);
return a;
}
// make a copy; must not be used as an lvalue
if(islvalue(n))
fatal("missing lvalue case in safeexpr: %N", n);
return cheapexpr(n, init);
}
static Node*
copyexpr(Node *n, Type *t, NodeList **init)
{
Node *a, *l;
l = temp(t);
a = nod(OAS, l, n);
typecheck(&a, Etop);
walkexpr(&a, init);
*init = list(*init, a);
return l;
}
/*
* return side-effect free and cheap n, appending side effects to init.
* result may not be assignable.
*/
Node*
cheapexpr(Node *n, NodeList **init)
{
switch(n->op) {
case ONAME:
case OLITERAL:
return n;
}
return copyexpr(n, n->type, init);
}
/*
* return n in a local variable of type t if it is not already.
*/
Node*
localexpr(Node *n, Type *t, NodeList **init)
{
if(n->op == ONAME &&
(n->class == PAUTO || n->class == PPARAM || n->class == PPARAMOUT) &&
convertop(n->type, t, nil) == OCONVNOP)
return n;
return copyexpr(n, t, init);
}
void
setmaxarg(Type *t)
{
int32 w;
dowidth(t);
w = t->argwid;
if(t->argwid >= MAXWIDTH)
fatal("bad argwid %T", t);
if(w > maxarg)
maxarg = w;
}
/*
* unicode-aware case-insensitive strcmp
*/
static int
ucistrcmp(char *p, char *q)
{
Rune rp, rq;
while(*p || *q) {
if(*p == 0)
return +1;
if(*q == 0)
return -1;
p += chartorune(&rp, p);
q += chartorune(&rq, q);
rp = tolowerrune(rp);
rq = tolowerrune(rq);
if(rp < rq)
return -1;
if(rp > rq)
return +1;
}
return 0;
}
/*
* code to resolve elided DOTs
* in embedded types
*/
// search depth 0 --
// return count of fields+methods
// found with a given name
static int
lookdot0(Sym *s, Type *t, Type **save, int ignorecase)
{
Type *f, *u;
int c;
u = t;
if(isptr[u->etype])
u = u->type;
c = 0;
if(u->etype == TSTRUCT || u->etype == TINTER) {
for(f=u->type; f!=T; f=f->down)
if(f->sym == s || (ignorecase && ucistrcmp(f->sym->name, s->name) == 0)) {
if(save)
*save = f;
c++;
}
}
u = methtype(t);
if(u != T) {
for(f=u->method; f!=T; f=f->down)
if(f->embedded == 0 && (f->sym == s || (ignorecase && ucistrcmp(f->sym->name, s->name) == 0))) {
if(save)
*save = f;
c++;
}
}
return c;
}
// search depth d --
// return count of fields+methods
// found at search depth.
// answer is in dotlist array and
// count of number of ways is returned.
int
adddot1(Sym *s, Type *t, int d, Type **save, int ignorecase)
{
Type *f, *u;
int c, a;
if(t->trecur)
return 0;
t->trecur = 1;
if(d == 0) {
c = lookdot0(s, t, save, ignorecase);
goto out;
}
c = 0;
u = t;
if(isptr[u->etype])
u = u->type;
if(u->etype != TSTRUCT && u->etype != TINTER)
goto out;
d--;
for(f=u->type; f!=T; f=f->down) {
if(!f->embedded)
continue;
if(f->sym == S)
continue;
a = adddot1(s, f->type, d, save, ignorecase);
if(a != 0 && c == 0)
dotlist[d].field = f;
c += a;
}
out:
t->trecur = 0;
return c;
}
// in T.field
// find missing fields that
// will give shortest unique addressing.
// modify the tree with missing type names.
Node*
adddot(Node *n)
{
Type *t;
Sym *s;
int c, d;
typecheck(&n->left, Etype|Erv);
t = n->left->type;
if(t == T)
goto ret;
if(n->left->op == OTYPE)
goto ret;
if(n->right->op != ONAME)
goto ret;
s = n->right->sym;
if(s == S)
goto ret;
for(d=0; d<nelem(dotlist); d++) {
c = adddot1(s, t, d, nil, 0);
if(c > 0)
goto out;
}
goto ret;
out:
if(c > 1)
yyerror("ambiguous DOT reference %T.%S", t, s);
// rebuild elided dots
for(c=d-1; c>=0; c--)
n->left = nod(ODOT, n->left, newname(dotlist[c].field->sym));
ret:
return n;
}
/*
* code to help generate trampoline
* functions for methods on embedded
* subtypes.
* these are approx the same as
* the corresponding adddot routines
* except that they expect to be called
* with unique tasks and they return
* the actual methods.
*/
typedef struct Symlink Symlink;
struct Symlink
{
Type* field;
uchar good;
uchar followptr;
Symlink* link;
};
static Symlink* slist;
static void
expand0(Type *t, int followptr)
{
Type *f, *u;
Symlink *sl;
u = t;
if(isptr[u->etype]) {
followptr = 1;
u = u->type;
}
if(u->etype == TINTER) {
for(f=u->type; f!=T; f=f->down) {
if(!exportname(f->sym->name) && f->sym->pkg != localpkg)
continue;
if(f->sym->flags & SymUniq)
continue;
f->sym->flags |= SymUniq;
sl = mal(sizeof(*sl));
sl->field = f;
sl->link = slist;
sl->followptr = followptr;
slist = sl;
}
return;
}
u = methtype(t);
if(u != T) {
for(f=u->method; f!=T; f=f->down) {
if(!exportname(f->sym->name) && f->sym->pkg != localpkg)
continue;
if(f->sym->flags & SymUniq)
continue;
f->sym->flags |= SymUniq;
sl = mal(sizeof(*sl));
sl->field = f;
sl->link = slist;
sl->followptr = followptr;
slist = sl;
}
}
}
static void
expand1(Type *t, int d, int followptr)
{
Type *f, *u;
if(t->trecur)
return;
if(d == 0)
return;
t->trecur = 1;
if(d != nelem(dotlist)-1)
expand0(t, followptr);
u = t;
if(isptr[u->etype]) {
followptr = 1;
u = u->type;
}
if(u->etype != TSTRUCT && u->etype != TINTER)
goto out;
for(f=u->type; f!=T; f=f->down) {
if(!f->embedded)
continue;
if(f->sym == S)
continue;
expand1(f->type, d-1, followptr);
}
out:
t->trecur = 0;
}
void
expandmeth(Sym *s, Type *t)
{
Symlink *sl;
Type *f;
int c, d;
if(s == S)
return;
if(t == T || t->xmethod != nil)
return;
// mark top-level method symbols
// so that expand1 doesn't consider them.
for(f=t->method; f != nil; f=f->down)
f->sym->flags |= SymUniq;
// generate all reachable methods
slist = nil;
expand1(t, nelem(dotlist)-1, 0);
// check each method to be uniquely reachable
for(sl=slist; sl!=nil; sl=sl->link) {
sl->field->sym->flags &= ~SymUniq;
for(d=0; d<nelem(dotlist); d++) {
c = adddot1(sl->field->sym, t, d, &f, 0);
if(c == 0)
continue;
if(c == 1) {
sl->good = 1;
sl->field = f;
}
break;
}
}
for(f=t->method; f != nil; f=f->down)
f->sym->flags &= ~SymUniq;
t->xmethod = t->method;
for(sl=slist; sl!=nil; sl=sl->link) {
if(sl->good) {
// add it to the base type method list
f = typ(TFIELD);
*f = *sl->field;
f->embedded = 1; // needs a trampoline
if(sl->followptr)
f->embedded = 2;
f->down = t->xmethod;
t->xmethod = f;
}
}
}
/*
* Given funarg struct list, return list of ODCLFIELD Node fn args.
*/
static NodeList*
structargs(Type **tl, int mustname)
{
Iter savet;
Node *a, *n;
NodeList *args;
Type *t;
char buf[100];
int gen;
args = nil;
gen = 0;
for(t = structfirst(&savet, tl); t != T; t = structnext(&savet)) {
n = N;
if(t->sym)
n = newname(t->sym);
else if(mustname) {
// have to give it a name so we can refer to it in trampoline
snprint(buf, sizeof buf, ".anon%d", gen++);
n = newname(lookup(buf));
}
a = nod(ODCLFIELD, n, typenod(t->type));
a->isddd = t->isddd;
if(n != N)
n->isddd = t->isddd;
args = list(args, a);
}
return args;
}
/*
* Generate a wrapper function to convert from
* a receiver of type T to a receiver of type U.
* That is,
*
* func (t T) M() {
* ...
* }
*
* already exists; this function generates
*
* func (u U) M() {
* u.M()
* }
*
* where the types T and U are such that u.M() is valid
* and calls the T.M method.
* The resulting function is for use in method tables.
*
* rcvr - U
* method - M func (t T)(), a TFIELD type struct
* newnam - the eventual mangled name of this function
*/
void
genwrapper(Type *rcvr, Type *method, Sym *newnam, int iface)
{
Node *this, *fn, *call, *n, *t, *pad;
NodeList *l, *args, *in, *out;
Type *tpad;
int isddd;
Val v;
if(0 && debug['r'])
print("genwrapper rcvrtype=%T method=%T newnam=%S\n",
rcvr, method, newnam);
lineno = 1; // less confusing than end of input
dclcontext = PEXTERN;
markdcl();
this = nod(ODCLFIELD, newname(lookup(".this")), typenod(rcvr));
this->left->ntype = this->right;
in = structargs(getinarg(method->type), 1);
out = structargs(getoutarg(method->type), 0);
fn = nod(ODCLFUNC, N, N);
fn->nname = newname(newnam);
t = nod(OTFUNC, N, N);
l = list1(this);
if(iface && rcvr->width < types[tptr]->width) {
// Building method for interface table and receiver
// is smaller than the single pointer-sized word
// that the interface call will pass in.
// Add a dummy padding argument after the
// receiver to make up the difference.
tpad = typ(TARRAY);
tpad->type = types[TUINT8];
tpad->bound = types[tptr]->width - rcvr->width;
pad = nod(ODCLFIELD, newname(lookup(".pad")), typenod(tpad));
l = list(l, pad);
}
t->list = concat(l, in);
t->rlist = out;
fn->nname->ntype = t;
funchdr(fn);
// arg list
args = nil;
isddd = 0;
for(l=in; l; l=l->next) {
args = list(args, l->n->left);
isddd = l->n->left->isddd;
}
// generate nil pointer check for better error
if(isptr[rcvr->etype] && rcvr->type == getthisx(method->type)->type->type) {
// generating wrapper from *T to T.
n = nod(OIF, N, N);
n->ntest = nod(OEQ, this->left, nodnil());
// these strings are already in the reflect tables,
// so no space cost to use them here.
l = nil;
v.ctype = CTSTR;
v.u.sval = strlit(rcvr->type->sym->pkg->name); // package name
l = list(l, nodlit(v));
v.u.sval = strlit(rcvr->type->sym->name); // type name
l = list(l, nodlit(v));
v.u.sval = strlit(method->sym->name);
l = list(l, nodlit(v)); // method name
call = nod(OCALL, syslook("panicwrap", 0), N);
call->list = l;
n->nbody = list1(call);
fn->nbody = list(fn->nbody, n);
}
// generate call
call = nod(OCALL, adddot(nod(OXDOT, this->left, newname(method->sym))), N);
call->list = args;
call->isddd = isddd;
if(method->type->outtuple > 0) {
n = nod(ORETURN, N, N);
n->list = list1(call);
call = n;
}
fn->nbody = list(fn->nbody, call);
if(0 && debug['r'])
dumplist("genwrapper body", fn->nbody);
funcbody(fn);
curfn = fn;
typecheck(&fn, Etop);
typechecklist(fn->nbody, Etop);
curfn = nil;
funccompile(fn, 0);
}
static Type*
ifacelookdot(Sym *s, Type *t, int *followptr, int ignorecase)
{
int i, c, d;
Type *m;
*followptr = 0;
if(t == T)
return T;
for(d=0; d<nelem(dotlist); d++) {
c = adddot1(s, t, d, &m, ignorecase);
if(c > 1) {
yyerror("%T.%S is ambiguous", t, s);
return T;
}
if(c == 1) {
for(i=0; i<d; i++) {
if(isptr[dotlist[i].field->type->etype]) {
*followptr = 1;
break;
}
}
if(m->type->etype != TFUNC || m->type->thistuple == 0) {
yyerror("%T.%S is a field, not a method", t, s);
return T;
}
return m;
}
}
return T;
}
int
implements(Type *t, Type *iface, Type **m, Type **samename, int *ptr)
{
Type *t0, *im, *tm, *rcvr, *imtype;
int followptr;
t0 = t;
if(t == T)
return 0;
// if this is too slow,
// could sort these first
// and then do one loop.
if(t->etype == TINTER) {
for(im=iface->type; im; im=im->down) {
for(tm=t->type; tm; tm=tm->down) {
if(tm->sym == im->sym) {
if(eqtype(tm->type, im->type))
goto found;
*m = im;
*samename = tm;
*ptr = 0;
return 0;
}
}
*m = im;
*samename = nil;
*ptr = 0;
return 0;
found:;
}
return 1;
}
t = methtype(t);
if(t != T)
expandmeth(t->sym, t);
for(im=iface->type; im; im=im->down) {
imtype = methodfunc(im->type, 0);
tm = ifacelookdot(im->sym, t, &followptr, 0);
if(tm == T || !eqtype(methodfunc(tm->type, 0), imtype)) {
if(tm == T)
tm = ifacelookdot(im->sym, t, &followptr, 1);
*m = im;
*samename = tm;
*ptr = 0;
return 0;
}
// if pointer receiver in method,
// the method does not exist for value types.
rcvr = getthisx(tm->type)->type->type;
if(isptr[rcvr->etype] && !isptr[t0->etype] && !followptr && !isifacemethod(tm->type)) {
if(0 && debug['r'])
yyerror("interface pointer mismatch");
*m = im;
*samename = nil;
*ptr = 1;
return 0;
}
}
return 1;
}
/*
* even simpler simtype; get rid of ptr, bool.
* assuming that the front end has rejected
* all the invalid conversions (like ptr -> bool)
*/
int
simsimtype(Type *t)
{
int et;
if(t == 0)
return 0;
et = simtype[t->etype];
switch(et) {
case TPTR32:
et = TUINT32;
break;
case TPTR64:
et = TUINT64;
break;
case TBOOL:
et = TUINT8;
break;
}
return et;
}
NodeList*
concat(NodeList *a, NodeList *b)
{
if(a == nil)
return b;
if(b == nil)
return a;
a->end->next = b;
a->end = b->end;
b->end = nil;
return a;
}
NodeList*
list1(Node *n)
{
NodeList *l;
if(n == nil)
return nil;
if(n->op == OBLOCK && n->ninit == nil) {
// Flatten list and steal storage.
// Poison pointer to catch errant uses.
l = n->list;
n->list = (NodeList*)1;
return l;
}
l = mal(sizeof *l);
l->n = n;
l->end = l;
return l;
}
NodeList*
list(NodeList *l, Node *n)
{
return concat(l, list1(n));
}
void
listsort(NodeList** l, int(*f)(Node*, Node*))
{
NodeList *l1, *l2, *le;
if(*l == nil || (*l)->next == nil)
return;
l1 = *l;
l2 = *l;
for(;;) {
l2 = l2->next;
if(l2 == nil)
break;
l2 = l2->next;
if(l2 == nil)
break;
l1 = l1->next;
}
l2 = l1->next;
l1->next = nil;
l2->end = (*l)->end;
(*l)->end = l1;
l1 = *l;
listsort(&l1, f);
listsort(&l2, f);
if((*f)(l1->n, l2->n) < 0) {
*l = l1;
} else {
*l = l2;
l2 = l1;
l1 = *l;
}
// now l1 == *l; and l1 < l2
while ((l1 != nil) && (l2 != nil)) {
while ((l1->next != nil) && (*f)(l1->next->n, l2->n) < 0)
l1 = l1->next;
// l1 is last one from l1 that is < l2
le = l1->next; // le is the rest of l1, first one that is >= l2
if(le != nil)
le->end = (*l)->end;
(*l)->end = l1; // cut *l at l1
*l = concat(*l, l2); // glue l2 to *l's tail
l1 = l2; // l1 is the first element of *l that is < the new l2
l2 = le; // ... because l2 now is the old tail of l1
}
*l = concat(*l, l2); // any remainder
}
NodeList*
listtreecopy(NodeList *l)
{
NodeList *out;
out = nil;
for(; l; l=l->next)
out = list(out, treecopy(l->n));
return out;
}
Node*
liststmt(NodeList *l)
{
Node *n;
n = nod(OBLOCK, N, N);
n->list = l;
if(l)
n->lineno = l->n->lineno;
return n;
}
/*
* return nelem of list
*/
int
count(NodeList *l)
{
int n;
n = 0;
for(; l; l=l->next)
n++;
return n;
}
/*
* return nelem of list
*/
int
structcount(Type *t)
{
int v;
Iter s;
v = 0;
for(t = structfirst(&s, &t); t != T; t = structnext(&s))
v++;
return v;
}
/*
* return power of 2 of the constant
* operand. -1 if it is not a power of 2.
* 1000+ if it is a -(power of 2)
*/
int
powtwo(Node *n)
{
uvlong v, b;
int i;
if(n == N || n->op != OLITERAL || n->type == T)
goto no;
if(!isint[n->type->etype])
goto no;
v = mpgetfix(n->val.u.xval);
b = 1ULL;
for(i=0; i<64; i++) {
if(b == v)
return i;
b = b<<1;
}
if(!issigned[n->type->etype])
goto no;
v = -v;
b = 1ULL;
for(i=0; i<64; i++) {
if(b == v)
return i+1000;
b = b<<1;
}
no:
return -1;
}
/*
* return the unsigned type for
* a signed integer type.
* returns T if input is not a
* signed integer type.
*/
Type*
tounsigned(Type *t)
{
// this is types[et+1], but not sure
// that this relation is immutable
switch(t->etype) {
default:
print("tounsigned: unknown type %T\n", t);
t = T;
break;
case TINT:
t = types[TUINT];
break;
case TINT8:
t = types[TUINT8];
break;
case TINT16:
t = types[TUINT16];
break;
case TINT32:
t = types[TUINT32];
break;
case TINT64:
t = types[TUINT64];
break;
}
return t;
}
/*
* magic number for signed division
* see hacker's delight chapter 10
*/
void
smagic(Magic *m)
{
int p;
uint64 ad, anc, delta, q1, r1, q2, r2, t;
uint64 mask, two31;
m->bad = 0;
switch(m->w) {
default:
m->bad = 1;
return;
case 8:
mask = 0xffLL;
break;
case 16:
mask = 0xffffLL;
break;
case 32:
mask = 0xffffffffLL;
break;
case 64:
mask = 0xffffffffffffffffLL;
break;
}
two31 = mask ^ (mask>>1);
p = m->w-1;
ad = m->sd;
if(m->sd < 0)
ad = -m->sd;
// bad denominators
if(ad == 0 || ad == 1 || ad == two31) {
m->bad = 1;
return;
}
t = two31;
ad &= mask;
anc = t - 1 - t%ad;
anc &= mask;
q1 = two31/anc;
r1 = two31 - q1*anc;
q1 &= mask;
r1 &= mask;
q2 = two31/ad;
r2 = two31 - q2*ad;
q2 &= mask;
r2 &= mask;
for(;;) {
p++;
q1 <<= 1;
r1 <<= 1;
q1 &= mask;
r1 &= mask;
if(r1 >= anc) {
q1++;
r1 -= anc;
q1 &= mask;
r1 &= mask;
}
q2 <<= 1;
r2 <<= 1;
q2 &= mask;
r2 &= mask;
if(r2 >= ad) {
q2++;
r2 -= ad;
q2 &= mask;
r2 &= mask;
}
delta = ad - r2;
delta &= mask;
if(q1 < delta || (q1 == delta && r1 == 0)) {
continue;
}
break;
}
m->sm = q2+1;
if(m->sm & two31)
m->sm |= ~mask;