diff --git a/mach/proto/mcg/table b/mach/proto/mcg/table
index dc0bc0b3d..daf0fbbad 100644
--- a/mach/proto/mcg/table
+++ b/mach/proto/mcg/table
@@ -1,37 +1,6 @@
-%{
-#if 0
-#include <stdio.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <stdbool.h>
+PATTERNS
 
-#define TRACE
-
-#define STATE_TYPE void*
-typedef struct tree {
-	int op;
-	struct tree *kids[2];
-	STATE_TYPE state_label;
-} *NODEPTR_TYPE;
-#define OP_LABEL(p) ((p)->op)
-#define LEFT_CHILD(p) ((p)->kids[0])
-#define RIGHT_CHILD(p) ((p)->kids[1])
-#define STATE_LABEL(p) ((p)->state_label)
-#define PANIC printf
-
-static void burm_trace(NODEPTR_TYPE p, int eruleno, int cost, int bestcost) {
-#ifdef TRACE
-	extern const char *burm_string[];
-
-	fprintf(stderr, "0x%p matched %s with cost %d vs. %d\n", p,
-		burm_string[eruleno], cost, bestcost);
-#endif
-}
-#endif
-%}
-%%
-
-	stm = STORE4(addr:address, value:reg)
+	STORE4(addr:address, value:reg)
 		ins value:GPR
 		emit "str %value, %addr"
 		cost 4;
@@ -49,7 +18,7 @@ static void burm_trace(NODEPTR_TYPE p, int eruleno, int cost, int bestcost) {
 		ins addr:GPR
 		fragment "[%addr]";
 
-	stm = reg;
+	reg;
 
 	reg = ADD4(left:reg, right:aluparam)
 		ins left:GPR, right:GPR
diff --git a/util/mcgg/gram.y b/util/mcgg/gram.y
index 5f100c7d2..82f8de7e1 100644
--- a/util/mcgg/gram.y
+++ b/util/mcgg/gram.y
@@ -7,14 +7,14 @@
 #define YYDEBUG 1
 
 static char rcsid[] = "$Id$";
-static int nextesn = 0;
-static int nextern = 0;
+static int nextern = 1;
 
 %}
 %union {
 	int n;
 	char* string;
 	Tree tree;
+    Rule rule;
     Stringlist stringlist;
     char* stringpair[2];
 }
@@ -36,37 +36,16 @@ static int nextern = 0;
 %token <string>     STRING
 
 %type  <n>          cost
-%type  <string>     lhs
+%type  <rule>       pattern
 %type  <stringlist> stringlist
 %type  <stringlist> when
 %type  <tree>       rhs
 %type  <stringpair> labelledid
 %%
 spec
-    : decls PPERCENT patterns
-	| decls
+    : PATTERNS patterns
 	;
 
-decls	: /* lambda */
-	| decls decl
-	;
-
-decl
-    : TERMINAL blist ';'
-	| START lhs ';'
-    {
-        if (nonterm($2)->number != 1)
-            yyerror("redeclaration of the start symbol\n");
-    }
-	| ';'
-	| error ';'			{ yyerrok; }
-	;
-
-blist
-    : /* nothing */
-    | blist ID              { term($2, nextesn++); }
-    ;
-
 patterns
     : /* nothing */
 	| patterns pattern ';'
@@ -75,13 +54,16 @@ patterns
 	;
 
 pattern
-    : lhs '=' rhs when ins outs emits cost { rule($1, $3, nextern++, $4, $8); }
+    : ID '=' rhs                      { nonterm($1); $$ = rule($1, $3, nextern++); }
+    | rhs                             {              $$ = rule("stmt", $1, nextern++); }
+    | pattern WHEN stringlist         { $$ = $1; $$->when = $3; }
+    | pattern INS ins                 { $$ = $1; }
+    | pattern OUTS outs               { $$ = $1; }
+    | pattern EMIT STRING             { $$ = $1; }
+    | pattern FRAGMENT STRING         { $$ = $1; }
+    | pattern COST INT                { $$ = $1; $$->cost = $3; }
     ;
 
-lhs
-    : ID				              { $$ = $1; nonterm($$); }
-	;
-
 rhs
     : labelledid                      { $$ = tree($1[1], $1[0], NULL, NULL); }
 	| labelledid '(' rhs ')'          { $$ = tree($1[1], $1[0],   $3, NULL); }
@@ -104,12 +86,7 @@ stringlist
     ;
     
 ins
-    : /* nothing */
-    | INS inslist
-    ;
-
-inslist
-    : inslist ',' in
+    : ins ',' in
     | in
     ;
 
@@ -118,12 +95,7 @@ in
     ;
 
 outs
-    : /* nothing */
-    | OUTS outslist
-    ;
-
-outslist
-    : outslist ',' out
+    : outs ',' out
     | out
     ;
 
@@ -131,22 +103,6 @@ out
     : ID ':' ID
     ;
 
-emits
-    : /* nothing */
-    | EMIT STRING
-    | FRAGMENT STRING
-    ;
-
-cost
-    : /* lambda */			          { $$ = 0; }
-	| COST INT  			          {
-                                          if ($2 > maxcost) {
-                                              yyerror("%d exceeds maximum cost of %d\n", $2, maxcost);
-                                              $$ = maxcost;
-                                          } else
-                                              $$ = $2;
-                                      }
-	;
 %%
 #include <stdarg.h>
 #include <ctype.h>
diff --git a/util/mcgg/iburg.c b/util/mcgg/iburg.c
index b4ef1442e..e581b7b90 100644
--- a/util/mcgg/iburg.c
+++ b/util/mcgg/iburg.c
@@ -60,7 +60,7 @@ int main(int argc, char* argv[])
 
 	for (;;)
 	{
-		int opt = getopt(argc, argv, "p:i:o:");
+		int opt = getopt(argc, argv, "p:i:o:y");
 		if (opt == -1)
 			break;
 
@@ -88,6 +88,13 @@ int main(int argc, char* argv[])
 				}
 				break;
 
+			case 'y':
+			{
+				extern int yydebug;
+				yydebug = 1;
+				break;
+			}
+
 			default:
 				yyerror("usage: %s [-p prefix] < input > output\n", argv[0]);
 				exit(1);
@@ -97,6 +104,8 @@ int main(int argc, char* argv[])
 	emitheader();
 	registerterminals();
 
+	start = nonterm("stmt");
+
 	yyin = infp;
 	yyparse();
 
@@ -308,14 +317,13 @@ Tree tree(const char* id, const char* label, Tree left, Tree right)
 }
 
 /* rule - create & initialize a rule with the given fields */
-Rule rule(char* id, Tree pattern, int ern, Stringlist when, int cost)
+Rule rule(char* id, Tree pattern, int ern)
 {
 	Rule r = calloc(1, sizeof *r);
 	Rule *q;
 	Term p = pattern->op;
 
 	nrules++;
-	r->when = when;
 	r->lhs = nonterm(id);
 	r->packed = ++r->lhs->lhscount;
 	for (q = &r->lhs->rules; *q; q = &(*q)->decode)
@@ -323,7 +331,6 @@ Rule rule(char* id, Tree pattern, int ern, Stringlist when, int cost)
 	*q = r;
 	r->pattern = pattern;
 	r->ern = ern;
-	r->cost = cost;
 	if (p->kind == TERM)
 	{
 		r->next = p->rules;
diff --git a/util/mcgg/iburg.h b/util/mcgg/iburg.h
index 59bbfd7d8..59c84a3ea 100644
--- a/util/mcgg/iburg.h
+++ b/util/mcgg/iburg.h
@@ -68,7 +68,7 @@ struct rule
 	Rule kids;       /* next rule with same burm_kids pattern */
 	Stringlist when; /* C predicate string */
 };
-extern Rule rule(char* id, Tree pattern, int ern, Stringlist when, int cost);
+extern Rule rule(char* id, Tree pattern, int ern);
 extern int maxcost; /* maximum cost */
 
 /* gram.y: */