yycstate improved

diff --git a/src/parser.y b/src/parser.y
index 3ec018b..3dd7364 100644 (file)
--- a/src/parser.y
+++ b/src/parser.y
@@ -2,15 +2,15 @@
 
 %code requires {
   #include <unitypes.h>
+  #include "ir.h"
+  typedef struct class_state_t yycstate;
+  struct frame_spec_t { ir_facing d; int w, h; };
 }
-
 %code provides {
-  typedef struct class_state_t yycstate;
   yycstate* yycstate_new(void);
   void      yycstate_delete(yycstate*);
 }
-
-%{
+%code {
   #include <stdio.h>
   #include <string.h>
   #include <dirent.h>
@@ -19,41 +19,32 @@
 
   struct class_state_t {
     ir_class *csp;
-    size_t class_stack_size;
-    ir_class *class_stack;
-
+    ir_class class_stack[];
   };
 
-  struct frame_spec_t { enum facing d; int w, h; };
-
   extern long     sys_pagesize;
   extern int      lexer();
   static void     yyerror(char const*);
   /* Stack-based class handler */
-  static ir_class class_stack_init(void);
-  #define         class_stack_pop() (*--csp)
-  static ir_class class_stack_push(ir_class);
-
-  #define yylex     lexer
-  #define yyclass   (*csp)
-  #define yyclassld (ir_classld_from_class(yyclass))
-
-  
-%}
+  #define CLASS_POP(CS) (*--(CS-csp))
+  #define CLASS_PUSH(CS,CL) (*(CS->csp)++ = CL
+  #define yyclass(CS)   (*(CS->csp))
+  #define yyclassld(CS) (ir_classld_from_class(yyclass(CS)))
+}
 %define parse.error verbose
 %define lr.type ielr
 %define api.pure full
 %define api.push-pull push
 %parse-param {yycstate* cs}
 %union {
-  long long   ref;
-  int         val;
-  enum facing face;
-  uint8_t*    str;
-  ir_class    class;
-  ir_set      set;
-  ir_setld    ld;
-  ir_setdata  data;
+  long long  ref;
+  int        val;
+  ir_facing  face;
+  uint8_t*   str;
+  ir_class   class;
+  ir_set     set;
+  ir_setld   ld;
+  ir_setdata data;
   struct frame_spec_t frame_spec;
 }
 /* Operators */
@@ -74,8 +65,6 @@
 %type<set>        set_spec
 %type<ld>         set_ld set_link
 %type<frame_spec> frame_spec
-/* Init */
-%initial-action { class_stack_init(); }
 %%
 /* Syntax Directed Translation Scheme of the APC grammar */
 progn:
@@ -90,9 +79,9 @@ class_list:
 ;
 
 class:
-  NAME CLOPEN   { class_stack_push(ir_class_addchild(yyclass, $1)); }
+  NAME CLOPEN   { CLASS_PUSH(cs,ir_class_addchild(yyclass, $1)); }
   progn
-  CLCLOSE       { class_stack_pop(); }
+  CLCLOSE       { CLASS_POP(cs); }
 ;
 
 statement_list:
@@ -142,84 +131,24 @@ frame_spec:
 
 %%
 
-#define ERR_ALLOC "memory allocation error\n"
-
-/* print to stderr */
 static
 void yyerror
 ( char const *s )
 { fprintf(stderr, "%s\n", s); }
 
-/* Initialize the class stack
-   If the class_stack hasn't been allocated yet, allocates a page for pointers
-   to be stored in.  Initializes class stack pointer, and inserts the root class
-   from IR
-   Returns the root class given by IR.
-*/
-static
-ir_class class_stack_init
-( void )
-{ if (class_stack == NULL)
-    { class_stack_size = (size_t) sys_pagesize;
-      class_stack = (ir_class*) malloc(class_stack_size);
-      if (class_stack == NULL)
-       { yyerror(ERR_MEM);
-         exit(1);
-       }
-    }
-  csp = class_stack;
-  return class_stack_push(ir_class_root());
-}
-
-/* Add a Class to the Stack
-   Allocated in page-sized chunks, potentially infinite depth is supported.
-   Returns the input class.
-*/
-static
-ir_class class_stack_push
-#define  class_size (sizeof(*class_stack))
-( ir_class class )
-{ size_t class_stack_len = csp - class_stack;
-  ir_class* new_class_stack;
-  if ((class_stack_len * class_size + class_size) > class_stack_size)
-    { class_stack_size += (size_t) sys_pagesize;
-      new_class_stack = (ir_class*) realloc(class_stack, class_stack_size);
-      if (new_class_stack == NULL)
-       { free(class_stack); //realloc failure does not free class_stack
-         yyerror("realloc " ERR_MEM);
-         exit(1);
-       }
-      class_stack = new_class_stack;
-      csp = class_stack + class_stack_len;
-    }
-  return (*csp++ = class);
-}
-
-yycstate*
-yycstate_new
+yycstate* yycstate_new
 ( void )
 { yycstate* class_state;
-
   class_state = (yycstate*) malloc((size_t) sys_pagesize);
-
   if(class_state == NULL)
     { yyerror(ERR_MEM);
       exit(1);
     }
-  
-  class_state.class_stack = class_stack;
-  class_state.csp = class_state.class_stack;
-  class_state.class_stack_size = (size_t) sys_pagesize;
-  class_stack_push(ir_class_root());
-
+  class_state->csp = &class_state->class_stack[0];
+  CLASS_PUSH(class_state, ir_class_root());
   return class_state;
-
 }
 
-void
-yycstate_delete
+void yycstate_delete
 ( yycstate* class_state )
-{
-  free(class_state);
- 
-}
+{ free(class_state); }