bug 137

R=r
OCL=26142
CL=26142

diff --git a/src/cmd/6g/gen.c b/src/cmd/6g/gen.c
index 9bc6126ab70f404dd86f99b3220cebb130890750..46c542aafd094305774cee6948b9976616ee474f 100644 (file)
--- a/src/cmd/6g/gen.c
+++ b/src/cmd/6g/gen.c
@@ -82,8 +82,8 @@ compile(Node *fn)
 //     inarggen();
 
        ginit();
-       gen(curfn->enter, L);
-       gen(curfn->nbody, L);
+       gen(curfn->enter);
+       gen(curfn->nbody);
        gclean();
        checklabels();
 
@@ -143,16 +143,29 @@ allocparams(void)
        }
 }
 
+void
+newlab(int op, Sym *s)
+{
+       Label *lab;
+
+       lab = mal(sizeof(*lab));
+       lab->link = labellist;
+       labellist = lab;
+
+       lab->sym = s;
+       lab->op = op;
+       lab->label = pc;
+}
+
 /*
  * compile statements
  */
 void
-gen(Node *n, Label *labloop)
+gen(Node *n)
 {
        int32 lno;
        Prog *scontin, *sbreak;
        Prog *p1, *p2, *p3;
-       Node *l;
        Label *lab;
 
        lno = setlineno(n);
@@ -160,8 +173,10 @@ gen(Node *n, Label *labloop)
 loop:
        if(n == N)
                goto ret;
+
+       p3 = pc;        // save pc for loop labels
        if(n->ninit)
-               gen(n->ninit, L);
+               gen(n->ninit);
 
        setlineno(n);
 
@@ -171,24 +186,8 @@ loop:
                break;
 
        case OLIST:
-               l = n->left;
-               gen(l, L);
-               if(l != N && l->op == OLABEL) {
-                       // call the next statement with a label
-                       l = n->right;
-                       if(l != N) {
-                               if(l->op != OLIST) {
-                                       gen(l, labellist);
-                                       break;
-                               }
-                               gen(l->left, labellist);
-                               n = l->right;
-                               labloop = L;
-                               goto loop;
-                       }
-               }
+               gen(n->left);
                n = n->right;
-               labloop = L;
                goto loop;
 
        case OPANIC:
@@ -203,37 +202,26 @@ loop:
                break;
 
        case OLABEL:
-               lab = mal(sizeof(*lab));
-               lab->link = labellist;
-               labellist = lab;
-               lab->sym = n->left->sym;
-
-               lab->op = OLABEL;
-               lab->label = pc;
+               newlab(OLABEL, n->left->sym);
                break;
 
        case OGOTO:
-               lab = mal(sizeof(*lab));
-               lab->link = labellist;
-               labellist = lab;
-               lab->sym = n->left->sym;
-
-               lab->op = OGOTO;
-               lab->label = pc;
+               newlab(OGOTO, n->left->sym);
                gbranch(AJMP, T);
                break;
 
        case OBREAK:
                if(n->left != N) {
-                       lab = findlab(n->left->sym);
-                       if(lab == L || lab->breakpc == P) {
-                               yyerror("break label is not defined: %S", n->left->sym);
-                               break;
+                       for(lab=labellist; lab!=L; lab=lab->link) {
+                               if(lab->breakpc != P) {
+                                       patch(gbranch(AJMP, T), lab->breakpc);
+                                       break;
+                               }
                        }
-                       patch(gbranch(AJMP, T), lab->breakpc);
+                       if(lab == L)
+                               yyerror("break label not defined: %S", n->left->sym);
                        break;
                }
-
                if(breakpc == P) {
                        yyerror("break is not in a loop");
                        break;
@@ -243,12 +231,14 @@ loop:
 
        case OCONTINUE:
                if(n->left != N) {
-                       lab = findlab(n->left->sym);
-                       if(lab == L || lab->continpc == P) {
-                               yyerror("continue label is not defined: %S", n->left->sym);
-                               break;
+                       for(lab=labellist; lab!=L; lab=lab->link) {
+                               if(lab->continpc != P) {
+                                       patch(gbranch(AJMP, T), lab->continpc);
+                                       break;
+                               }
                        }
-                       patch(gbranch(AJMP, T), lab->continpc);
+                       if(lab == L)
+                               yyerror("break label not defined: %S", n->left->sym);
                        break;
                }
 
@@ -265,18 +255,24 @@ loop:
                breakpc = gbranch(AJMP, T);             // break:       goto done
                scontin = continpc;
                continpc = pc;
-               gen(n->nincr, L);                               // contin:      incr
+
+               // define break and cotinue labels
+               for(lab=labellist; lab!=L; lab=lab->link) {
+                       if(lab->label != p3)
+                               break;
+                       if(lab->op == OLABEL) {
+                               lab->breakpc = breakpc;
+                               lab->continpc = continpc;
+                       }
+               }
+
+               gen(n->nincr);                          // contin:      incr
                patch(p1, pc);                          // test:
                if(n->ntest != N)
                        if(n->ntest->ninit != N)
-                               gen(n->ntest->ninit, L);
+                               gen(n->ntest->ninit);
                bgen(n->ntest, 0, breakpc);             //              if(!test) goto break
-               if(labloop != L) {
-                       labloop->op = OFOR;
-                       labloop->continpc = continpc;
-                       labloop->breakpc = breakpc;
-               }
-               gen(n->nbody, L);                       //              body
+               gen(n->nbody);                          //              body
                patch(gbranch(AJMP, T), continpc);      //              goto contin
                patch(breakpc, pc);                     // done:
                continpc = scontin;
@@ -289,12 +285,12 @@ loop:
                patch(p1, pc);                          // test:
                if(n->ntest != N)
                        if(n->ntest->ninit != N)
-                               gen(n->ntest->ninit, L);
+                               gen(n->ntest->ninit);
                bgen(n->ntest, 0, p2);                  //              if(!test) goto p2
-               gen(n->nbody, L);                       //              then
+               gen(n->nbody);                          //              then
                p3 = gbranch(AJMP, T);                  //              goto done
                patch(p2, pc);                          // else:
-               gen(n->nelse, L);                       //              else
+               gen(n->nelse);                          //              else
                patch(p3, pc);                          // done:
                break;
 
@@ -302,12 +298,18 @@ loop:
                sbreak = breakpc;
                p1 = gbranch(AJMP, T);                  //              goto test
                breakpc = gbranch(AJMP, T);             // break:       goto done
-               patch(p1, pc);                          // test:
-               if(labloop != L) {
-                       labloop->op = OFOR;
-                       labloop->breakpc = breakpc;
+
+               // define break label
+               for(lab=labellist; lab!=L; lab=lab->link) {
+                       if(lab->label != p3)
+                               break;
+                       if(lab->op == OLABEL) {
+                               lab->breakpc = breakpc;
+                       }
                }
-               gen(n->nbody, L);                       //              switch(test) body
+
+               patch(p1, pc);                          // test:
+               gen(n->nbody);                          //              switch(test) body
                patch(breakpc, pc);                     // done:
                breakpc = sbreak;
                break;
@@ -316,12 +318,18 @@ loop:
                sbreak = breakpc;
                p1 = gbranch(AJMP, T);                  //              goto test
                breakpc = gbranch(AJMP, T);             // break:       goto done
-               patch(p1, pc);                          // test:
-               if(labloop != L) {
-                       labloop->op = OFOR;
-                       labloop->breakpc = breakpc;
+
+               // define break label
+               for(lab=labellist; lab!=L; lab=lab->link) {
+                       if(lab->label != p3)
+                               break;
+                       if(lab->op == OLABEL) {
+                               lab->breakpc = breakpc;
+                       }
                }
-               gen(n->nbody, L);                       //              select() body
+
+               patch(p1, pc);                          // test:
+               gen(n->nbody);                          //              select() body
                patch(breakpc, pc);                     // done:
                breakpc = sbreak;
                break;
@@ -484,7 +492,7 @@ cgen_callinter(Node *n, Node *res, int proc)
                i = &tmpi;
        }
 
-       gen(n->right, L);               // args
+       gen(n->right);                  // args
 
        regalloc(&nodr, types[tptr], res);
        regalloc(&nodo, types[tptr], &nodr);
@@ -561,7 +569,7 @@ cgen_call(Node *n, int proc)
                cgen(n->left, &afun);
        }
 
-       gen(n->right, L);       // assign the args
+       gen(n->right);          // assign the args
        t = n->left->type;
 
        setmaxarg(t);
@@ -694,7 +702,7 @@ cgen_aret(Node *n, Node *res)
 void
 cgen_ret(Node *n)
 {
-       gen(n->left, L);        // copy out args
+       gen(n->left);           // copy out args
        if(hasdefer)
                ginscall(deferreturn, 0);
        gins(ARET, N, N);

diff --git a/src/cmd/6g/gg.h b/src/cmd/6g/gg.h
index 741527c432f1d99fe83d8f89f689f550037bc415..ae165ca833fd982ef6c65c1e50b0d79f08975282 100644 (file)
--- a/src/cmd/6g/gg.h
+++ b/src/cmd/6g/gg.h
@@ -74,7 +74,7 @@ struct        Pool
 typedef        struct  Label Label;
 struct Label
 {
-       uchar   op;             // OFOR/OGOTO/OLABEL
+       uchar   op;             // OGOTO/OLABEL
        Sym*    sym;
        Prog*   label;          // pointer to code
        Prog*   breakpc;        // pointer to code
@@ -133,7 +133,7 @@ EXTERN      int     sizeof_Array;   // runtime sizeof(Array)
  */
 void   compile(Node*);
 void   proglist(void);
-void   gen(Node*, Label*);
+void   gen(Node*);
 Node*  lookdot(Node*, Node*, int);
 void   inarggen(void);
 void   cgen_as(Node*, Node*);

diff --git a/test/bugs/bug137.go b/test/fixedbugs/bug137.go
similarity index 100%
rename from test/bugs/bug137.go
rename to test/fixedbugs/bug137.go

diff --git a/test/golden.out b/test/golden.out
index 181da52297d0e13733d951b7da74108a78c48c82..64f7e25863020e233641370e334a0462d33c334a 100644 (file)
--- a/test/golden.out
+++ b/test/golden.out
@@ -140,11 +140,6 @@ BUG: compilation succeeds incorrectly
 =========== bugs/bug136.go
 BUG: should not compile
 
-=========== bugs/bug137.go
-bugs/bug137.go:9: break label is not defined: L2
-bugs/bug137.go:15: break label is not defined: L4
-BUG should compile
-
 =========== bugs/bug138.go
 bugs/bug138.go:8: overflow converting constant to uint
 bugs/bug138.go:8: illegal combination of literals CONV 7