]> Cypherpunks repositories - gostls13.git/commitdiff
the last bug involving type hashes
authorRuss Cox <rsc@golang.org>
Wed, 2 Sep 2009 16:09:32 +0000 (09:09 -0700)
committerRuss Cox <rsc@golang.org>
Wed, 2 Sep 2009 16:09:32 +0000 (09:09 -0700)
R=ken
OCL=34244
CL=34249

src/cmd/gc/Makefile
src/cmd/gc/go.h
src/cmd/gc/md5.c [new file with mode: 0644]
src/cmd/gc/md5.h [new file with mode: 0644]
src/cmd/gc/reflect.c
src/cmd/gc/subr.c
src/cmd/gc/swt.c
test/fixedbugs/bug201.go [new file with mode: 0644]

index c7fa3d6d7193d2f605f69c91527fd0c08cc1dc63..1e116a9acffa792d96078f53a98c5b12ed7f336a 100644 (file)
@@ -10,6 +10,7 @@ LIB=\
 HFILES=\
        go.h\
        y.tab.h\
+       md5.h\
 
 YFILES=\
        go.y\
@@ -25,6 +26,7 @@ OFILES=\
        gen.$O\
        init.$O\
        lex.$O\
+       md5.$O\
        mparith1.$O\
        mparith2.$O\
        mparith3.$O\
index bcbc5f84c83b332d3bc42e6010e98b0178f49952..b4cf07a7545935f9cfde5a17163d51e7014fe512 100644 (file)
@@ -814,7 +814,7 @@ int cvttype(Type*, Type*);
 int    eqtypenoname(Type*, Type*);
 void   argtype(Node*, Type*);
 int    eqargs(Type*, Type*);
-uint32 typehash(Type*, int, int);
+uint32 typehash(Type*);
 void   frame(int);
 Node*  nodintconst(int64);
 void   nodconst(Node*, Type*, int64);
diff --git a/src/cmd/gc/md5.c b/src/cmd/gc/md5.c
new file mode 100644 (file)
index 0000000..7cea1a6
--- /dev/null
@@ -0,0 +1,290 @@
+// 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.
+
+// 64-bit MD5 (does full MD5 but returns 64 bits only).
+// Translation of ../../pkg/crypto/md5/md5*.go.
+
+#include "go.h"
+#include "md5.h"
+
+static int md5block(MD5 *dig, uchar *p, int nn);
+
+enum {
+       _Chunk = 64
+};
+
+#define _Init0 0x67452301
+#define _Init1 0xEFCDAB89
+#define _Init2 0x98BADCFE
+#define _Init3 0x10325476
+
+void
+md5reset(MD5 *d)
+{
+       d->s[0] = _Init0;
+       d->s[1] = _Init1;
+       d->s[2] = _Init2;
+       d->s[3] = _Init3;
+       d->nx = 0;
+       d->len = 0;
+}
+
+void
+md5write(MD5 *d, uchar *p, int nn)
+{
+       int i, n;
+
+       d->len += nn;
+       if(d->nx > 0) {
+               n = nn;
+               if(n > _Chunk - d->nx)
+                       n = _Chunk - d->nx;
+               for(i=0; i<n; i++)
+                       d->x[d->nx+i] = p[i];
+               d->nx += n;
+               if(d->nx == _Chunk) {
+                       md5block(d, d->x, _Chunk);
+                       d->nx = 0;
+               }
+               p += n;
+               nn -= n;
+       }
+       n = md5block(d, p, nn);
+       p += n;
+       nn -= n;
+       if(nn > 0) {
+               for(i=0; i<nn; i++)
+                       d->x[i] = p[i];
+               d->nx = nn;
+       }
+}
+
+uint64
+md5sum(MD5 *d)
+{
+       uchar tmp[64];
+       int i;
+       uint64 len;
+
+       // Padding.  Add a 1 bit and 0 bits until 56 bytes mod 64.
+       len = d->len;
+       memset(tmp, 0, sizeof tmp);
+       tmp[0] = 0x80;
+       if(len%64 < 56)
+               md5write(d, tmp, 56-len%64);
+       else
+               md5write(d, tmp, 64+56-len%64);
+
+       // Length in bits.
+       len <<= 3;
+       for(i=0; i<8; i++)
+               tmp[i] = len>>(8*i);
+       md5write(d, tmp, 8);
+
+       if(d->nx != 0)
+               fatal("md5sum");
+
+       return d->s[0] | ((uint64)d->s[1]<<32);
+}
+
+
+// MD5 block step.
+// In its own file so that a faster assembly or C version
+// can be substituted easily.
+
+// table[i] = int((1<<32) * abs(sin(i+1 radians))).
+static uint32 table[64] = {
+       // round 1
+       0xd76aa478,
+       0xe8c7b756,
+       0x242070db,
+       0xc1bdceee,
+       0xf57c0faf,
+       0x4787c62a,
+       0xa8304613,
+       0xfd469501,
+       0x698098d8,
+       0x8b44f7af,
+       0xffff5bb1,
+       0x895cd7be,
+       0x6b901122,
+       0xfd987193,
+       0xa679438e,
+       0x49b40821,
+
+       // round 2
+       0xf61e2562,
+       0xc040b340,
+       0x265e5a51,
+       0xe9b6c7aa,
+       0xd62f105d,
+       0x2441453,
+       0xd8a1e681,
+       0xe7d3fbc8,
+       0x21e1cde6,
+       0xc33707d6,
+       0xf4d50d87,
+       0x455a14ed,
+       0xa9e3e905,
+       0xfcefa3f8,
+       0x676f02d9,
+       0x8d2a4c8a,
+
+       // round3
+       0xfffa3942,
+       0x8771f681,
+       0x6d9d6122,
+       0xfde5380c,
+       0xa4beea44,
+       0x4bdecfa9,
+       0xf6bb4b60,
+       0xbebfbc70,
+       0x289b7ec6,
+       0xeaa127fa,
+       0xd4ef3085,
+       0x4881d05,
+       0xd9d4d039,
+       0xe6db99e5,
+       0x1fa27cf8,
+       0xc4ac5665,
+
+       // round 4
+       0xf4292244,
+       0x432aff97,
+       0xab9423a7,
+       0xfc93a039,
+       0x655b59c3,
+       0x8f0ccc92,
+       0xffeff47d,
+       0x85845dd1,
+       0x6fa87e4f,
+       0xfe2ce6e0,
+       0xa3014314,
+       0x4e0811a1,
+       0xf7537e82,
+       0xbd3af235,
+       0x2ad7d2bb,
+       0xeb86d391,
+};
+
+static uint32 shift1[] = { 7, 12, 17, 22 };
+static uint32 shift2[] = { 5, 9, 14, 20 };
+static uint32 shift3[] = { 4, 11, 16, 23 };
+static uint32 shift4[] = { 6, 10, 15, 21 };
+
+static int
+md5block(MD5 *dig, uchar *p, int nn)
+{
+       uint32 a, b, c, d, aa, bb, cc, dd;
+       int i, j, n;
+       uint32 X[16];
+
+       a = dig->s[0];
+       b = dig->s[1];
+       c = dig->s[2];
+       d = dig->s[3];
+       n = 0;
+
+       while(nn >= _Chunk) {
+               aa = a;
+               bb = b;
+               cc = c;
+               dd = d;
+
+               for(i=0; i<16; i++) {
+                       j = i*4;
+                       X[i] = p[j] | (p[j+1]<<8) | (p[j+2]<<16) | (p[j+3]<<24);
+               }
+
+               // Round 1.
+               for(i=0; i<16; i++) {
+                       uint32 x, t, s, f;
+                       x = i;
+                       t = i;
+                       s = shift1[i%4];
+                       f = ((c ^ d) & b) ^ d;
+                       a += f + X[x] + table[t];
+                       a = a<<s | a>>(32-s);
+                       a += b;
+
+                       t = d;
+                       d = c;
+                       c = b;
+                       b = a;
+                       a = t;
+               }
+
+               // Round 2.
+               for(i=0; i<16; i++) {
+                       uint32 x, t, s, g;
+
+                       x = (1+5*i)%16;
+                       t = 16+i;
+                       s = shift2[i%4];
+                       g = ((b ^ c) & d) ^ c;
+                       a += g + X[x] + table[t];
+                       a = a<<s | a>>(32-s);
+                       a += b;
+
+                       t = d;
+                       d = c;
+                       c = b;
+                       b = a;
+                       a = t;
+               }
+
+               // Round 3.
+               for(i=0; i<16; i++) {
+                       uint32 x, t, s, h;
+
+                       x = (5+3*i)%16;
+                       t = 32+i;
+                       s = shift3[i%4];
+                       h = b ^ c ^ d;
+                       a += h + X[x] + table[t];
+                       a = a<<s | a>>(32-s);
+                       a += b;
+
+                       t = d;
+                       d = c;
+                       c = b;
+                       b = a;
+                       a = t;
+               }
+
+               // Round 4.
+               for(i=0; i<16; i++) {
+                       uint32 x, s, t, ii;
+
+                       x = (7*i)%16;
+                       s = shift4[i%4];
+                       t = 48+i;
+                       ii = c ^ (b | ~d);
+                       a += ii + X[x] + table[t];
+                       a = a<<s | a>>(32-s);
+                       a += b;
+
+                       t = d;
+                       d = c;
+                       c = b;
+                       b = a;
+                       a = t;
+               }
+
+               a += aa;
+               b += bb;
+               c += cc;
+               d += dd;
+
+               p += _Chunk;
+               n += _Chunk;
+               nn -= _Chunk;
+       }
+
+       dig->s[0] = a;
+       dig->s[1] = b;
+       dig->s[2] = c;
+       dig->s[3] = d;
+       return n;
+}
diff --git a/src/cmd/gc/md5.h b/src/cmd/gc/md5.h
new file mode 100644 (file)
index 0000000..f153e30
--- /dev/null
@@ -0,0 +1,16 @@
+// 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.
+
+typedef struct MD5 MD5;
+struct MD5
+{
+       uint32 s[4];
+       uchar x[64];
+       int nx;
+       uint64 len;
+};
+
+void md5reset(MD5*);
+void md5write(MD5*, uchar*, int);
+uint64 md5sum(MD5*);
index c82875ca894b0a34ec872cd49f4676ab3075cc2a..da63cd0d776878182fe85f4a70877b02fbc39f87 100644 (file)
@@ -172,7 +172,7 @@ methods(Type *t)
                a = b;
 
                a->name = method->name;
-               a->hash = PRIME8*stringhash(a->name) + PRIME9*typehash(f->type, 0, 0);
+               a->hash = PRIME8*stringhash(a->name) + PRIME9*typehash(f->type);
                if(!exportname(a->name)) {
                        a->package = method->package;
                        a->hash += PRIME10*stringhash(a->package);
@@ -248,7 +248,7 @@ imethods(Type *t)
                a = b;
 
                a->name = f->sym->name;
-               a->hash = PRIME8*stringhash(a->name) + PRIME9*typehash(f->type, 0, 0);
+               a->hash = PRIME8*stringhash(a->name) + PRIME9*typehash(f->type);
                if(!exportname(a->name)) {
                        a->package = f->sym->package;
                        a->hash += PRIME10*stringhash(a->package);
@@ -411,7 +411,7 @@ dcommontype(Sym *s, int ot, Type *t)
        //              *nameInfo;
        //      }
        ot = duintptr(s, ot, t->width);
-       ot = duint32(s, ot, typehash(t, 1, 0));
+       ot = duint32(s, ot, typehash(t));
        ot = duint8(s, ot, algtype(t));
        elem = t;
        while(elem->etype == TARRAY && elem->bound >= 0)
index 0c436de0b99f20437159883f23e8e66094db98d2..9f160d456dd791b11a21d2a46663ee61c066d25b 100644 (file)
@@ -3,6 +3,7 @@
 // license that can be found in the LICENSE file.
 
 #include       "go.h"
+#include       "md5.h"
 #include       "y.tab.h"
 #include       "opnames.h"
 
@@ -1892,53 +1893,35 @@ eqargs(Type *t1, Type *t2)
        return 1;
 }
 
+/*
+ * 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 (which calls Tpretty, above) 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 *at, int addsym, int d)
+typehash(Type *t)
 {
-       uint32 h;
-       Type *t;
-
-       if(at == T)
-               return PRIME2;
-       if(d >= 5)
-               return PRIME3;
-
-       h = at->etype*PRIME4;
-
-       if(addsym && at->sym != S)
-               h += stringhash(at->sym->name);
-
-       switch(at->etype) {
-       default:
-               h += PRIME5 * typehash(at->type, addsym, d+1);
-               break;
-
-       case TINTER:
-               // botch -- should be sorted?
-               for(t=at->type; t!=T; t=t->down)
-                       h += PRIME6 * typehash(t, addsym, d+1);
-               break;
-
-       case TSTRUCT:
-               for(t=at->type; t!=T; t=t->down) {
-                       if(at->funarg)  // walk into TFIELD in function argument struct
-                               h += PRIME7 * typehash(t->type, addsym, d+1);
-                       else
-                               h += PRIME7 * typehash(t, addsym, d+1);
-               }
-               break;
-
-       case TFUNC:
-               t = at->type;
-               // skip this (receiver) argument
-               if(t != T)
-                       t = t->down;
-               for(; t!=T; t=t->down)
-                       h += PRIME7 * typehash(t, addsym, d+1);
-               break;
-       }
+       char *p;
+       MD5 d;
 
-       return h;
+       if(t->thistuple) {
+               // hide method receiver from Tpretty
+               t->thistuple = 0;
+               p = smprint("%#-T", t);
+               t->thistuple = 1;
+       }else
+               p = smprint("%#-T", t);
+       md5reset(&d);
+       md5write(&d, (uchar*)p, strlen(p));
+       free(p);
+       return md5sum(&d);
 }
 
 Type*
@@ -2747,7 +2730,7 @@ ifacelookdot(Sym *s, Type *t, int *followptr)
 // check whether non-interface type t
 // satisifes inteface type iface.
 int
-ifaceokT2I(Type *t0, Type *iface, Type **m)
+ifaceokT2I(Type *t0, Type *iface, Type **m, Type **samename)
 {
        Type *t, *im, *tm, *rcvr;
        int imhash, followptr;
@@ -2766,10 +2749,11 @@ ifaceokT2I(Type *t0, Type *iface, Type **m)
        // so we can both be wrong together.
 
        for(im=iface->type; im; im=im->down) {
-               imhash = typehash(im, 0, 0);
+               imhash = typehash(im->type);
                tm = ifacelookdot(im->sym, t, &followptr);
-               if(tm == T || typehash(tm, 0, 0) != imhash) {
+               if(tm == T || typehash(tm->type) != imhash) {
                        *m = im;
+                       *samename = tm;
                        return 0;
                }
                // if pointer receiver in method,
@@ -2779,6 +2763,7 @@ ifaceokT2I(Type *t0, Type *iface, Type **m)
                        if(debug['r'])
                                yyerror("interface pointer mismatch");
                        *m = im;
+                       *samename = nil;
                        return 0;
                }
        }
@@ -2797,7 +2782,7 @@ ifaceokI2I(Type *i1, Type *i2, Type **m)
 
        for(m2=i2->type; m2; m2=m2->down) {
                for(m1=i1->type; m1; m1=m1->down)
-                       if(m1->sym == m2->sym && typehash(m1, 0, 0) == typehash(m2, 0, 0))
+                       if(m1->sym == m2->sym && typehash(m1) == typehash(m2))
                                goto found;
                *m = m2;
                return 0;
@@ -2811,7 +2796,7 @@ runifacechecks(void)
 {
        Icheck *p;
        int lno, wrong, needexplicit;
-       Type *m, *t, *iface;
+       Type *m, *t, *iface, *samename;
 
        lno = lineno;
        for(p=icheck; p; p=p->next) {
@@ -2819,6 +2804,7 @@ runifacechecks(void)
                wrong = 0;
                needexplicit = 0;
                m = nil;
+               samename = nil;
                if(isinter(p->dst) && isinter(p->src)) {
                        iface = p->dst;
                        t = p->src;
@@ -2827,20 +2813,26 @@ runifacechecks(void)
                else if(isinter(p->dst)) {
                        t = p->src;
                        iface = p->dst;
-                       wrong = !ifaceokT2I(t, iface, &m);
+                       wrong = !ifaceokT2I(t, iface, &m, &samename);
                } else {
                        t = p->dst;
                        iface = p->src;
-                       wrong = !ifaceokT2I(t, iface, &m);
+                       wrong = !ifaceokT2I(t, iface, &m, &samename);
                        needexplicit = 1;
                }
-               if(wrong)
+               if(wrong) {
                        yyerror("%T is not %T\n\tmissing %S%hhT",
                                t, iface, m->sym, m->type);
+                       if(samename)
+                               print("\tdo have %S%hhT\n", samename->sym, samename->type);
+               }
                else if(!p->explicit && needexplicit) {
-                       if(m)
+                       if(m) {
                                yyerror("need type assertion to use %T as %T\n\tmissing %S%hhT",
                                        p->src, p->dst, m->sym, m->type);
+                               if(samename)
+                                       print("\tdo have %S%hhT\n", samename->sym, samename->type);
+                       }
                        else
                                yyerror("need type assertion to use %T as %T",
                                        p->src, p->dst);
index 0754d18f5a5a89801a36908691106f2b412d9f13..002bd4ed5d8d93429e5a7717d42f186d2640a8ff 100644 (file)
@@ -357,7 +357,7 @@ mkcaselist(Node *sw, int arg)
                                continue;
                        }
 
-                       c->hash = typehash(n->left->left->type, 1, 0);
+                       c->hash = typehash(n->left->left->type);
                        c->type = Ttypeconst;
                        continue;
 
diff --git a/test/fixedbugs/bug201.go b/test/fixedbugs/bug201.go
new file mode 100644 (file)
index 0000000..81989ff
--- /dev/null
@@ -0,0 +1,36 @@
+// $G $D/$F.go && $L $F.$A && ./$A.out
+
+// 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.
+
+package main
+
+type T1 struct { x, y int; }
+type T2 struct { z, w byte; }
+type T3 T1
+
+type MyInt int
+func (MyInt) m(*T1) { }
+
+func main() {
+       {
+               var i interface{} = new(T1);
+               v1, ok1 := i.(*T1);
+               v2, ok2 := i.(*T2);
+               v3, ok3 := i.(*T3);
+               if !ok1 || ok2 || ok3 {
+                       panicln("*T1", ok1, ok2, ok3);
+               }
+       }
+       {
+               var i interface{} = MyInt(0);
+               v1, ok1 := i.(interface{ m(*T1) });
+               v2, ok2 := i.(interface{ m(*T2) });
+               v3, ok3 := i.(interface{ m(*T3) });
+               if !ok1 || ok2 || ok3 {
+                       panicln("T", ok1, ok2, ok3);
+               }
+       }
+}
+