Commit 9654b141 authored by Ondrej Zajicek (work)'s avatar Ondrej Zajicek (work)
Browse files

Filter: Improve handling of stack frames in filter bytecode 

When f_line is done, we have to pop the stack frame. The old code just
removed nominal number of args/vars. Change it to use stored ventry value
modified by number of returned values. This allows to allocate variables
on a stack frame during execution of f_lines instead of just at start.

But we need to know the number of returned values for a f_line. It is 1
for term, 0 for cmd. Store that to f_line during linearization.
parent d07893fb

conf/confbase.Y

+2 −2
Original line number Diff line number Diff line
@@ -153,14 +153,14 @@ conf: definition ; 
definition:

   DEFINE symbol '=' term ';' {

     struct f_val *val = cfg_allocz(sizeof(struct f_val));

     if (f_eval(f_linearize($4), cfg_mem, val) > F_RETURN) cf_error("Runtime error");

     if (f_eval(f_linearize($4, 1), cfg_mem, val) > F_RETURN) cf_error("Runtime error");

     cf_define_symbol($2, SYM_CONSTANT | val->type, val, val);

   }

 ;



expr:

   NUM

 | '(' term ')' { $$ = f_eval_int(f_linearize($2)); }

 | '(' term ')' { $$ = f_eval_int(f_linearize($2, 1)); }

 | CF_SYM_KNOWN {

     if ($1->class != (SYM_CONSTANT | T_INT)) cf_error("Number constant expected");

     $$ = SYM_VAL($1).i; }

filter/config.Y

+7 −7
Original line number Diff line number Diff line
@@ -329,7 +329,7 @@ filter_def: 


conf: filter_eval ;

filter_eval:

   EVAL term { f_eval_int(f_linearize($2)); }

   EVAL term { f_eval_int(f_linearize($2, 1)); }

 ;



conf: custom_attr ;
@@ -453,7 +453,7 @@ where_filter: 


function_body:

   function_vars '{' cmds '}' {

     $$ = f_linearize($3);

     $$ = f_linearize($3, 0);

     $$->vars = $1;

   }

 ;
@@ -537,7 +537,7 @@ set_atom: 
 | VPN_RD { $$.type = T_RD; $$.val.ec = $1; }

 | ENUM   { $$.type = pair_a($1); $$.val.i = pair_b($1); }

 | '(' term ')' {

     if (f_eval(f_linearize($2), cfg_mem, &($$)) > F_RETURN) cf_error("Runtime error");

     if (f_eval(f_linearize($2, 1), cfg_mem, &($$)) > F_RETURN) cf_error("Runtime error");

     if (!f_valid_set_type($$.type)) cf_error("Set-incompatible type");

   }

 | CF_SYM_KNOWN {
@@ -549,13 +549,13 @@ set_atom: 


switch_atom:

   NUM   { $$.type = T_INT; $$.val.i = $1; }

 | '(' term ')' { $$.type = T_INT; $$.val.i = f_eval_int(f_linearize($2)); }

 | '(' term ')' { $$.type = T_INT; $$.val.i = f_eval_int(f_linearize($2, 1)); }

 | fipa  { $$ = $1; }

 | ENUM  { $$.type = pair_a($1); $$.val.i = pair_b($1); }

 ;



cnum:

   term { $$ = f_eval_int(f_linearize($1)); }

   term { $$ = f_eval_int(f_linearize($1, 1)); }



pair_item:

   '(' cnum ',' cnum ')'		{ $$ = f_new_pair_item($2, $2, $4, $4); }
@@ -642,7 +642,7 @@ switch_body: /* EMPTY */ { $$ = NULL; } 
 | switch_body switch_items ':' cmds  {

     /* Fill data fields */

     struct f_tree *t;

     struct f_line *line = f_linearize($4);

     struct f_line *line = f_linearize($4, 0);

     for (t = $2; t; t = t->left)

       t->data = line;

     $$ = f_merge_items($1, $2);
@@ -651,7 +651,7 @@ switch_body: /* EMPTY */ { $$ = NULL; } 
     struct f_tree *t = f_new_tree();

     t->from.type = t->to.type = T_VOID;

     t->right = t;

     t->data = f_linearize($3);

     t->data = f_linearize($3, 0);

     $$ = f_merge_items($1, t);

 }

 ;

filter/decl.m4

+4 −2
Original line number Diff line number Diff line
@@ -216,7 +216,7 @@ whati->f$1 = f$1; 
FID_DUMP_BODY()m4_dnl

f_dump_line(item->fl$1, indent + 1);

FID_LINEARIZE_BODY()m4_dnl

item->fl$1 = f_linearize(whati->f$1);

item->fl$1 = f_linearize(whati->f$1, $2);

FID_SAME_BODY()m4_dnl

if (!f_same(f1->fl$1, f2->fl$1)) return 0;

FID_ITERATE_BODY()m4_dnl
@@ -568,7 +568,7 @@ FID_WR_PUT(8) 
}



struct f_line *

f_linearize_concat(const struct f_inst * const inst[], uint count)

f_linearize_concat(const struct f_inst * const inst[], uint count, uint results)

{

  uint len = 0;

  for (uint i=0; i<count; i++)
@@ -580,6 +580,8 @@ f_linearize_concat(const struct f_inst * const inst[], uint count) 
  for (uint i=0; i<count; i++)

    out->len = linearize(out, inst[i], out->len);



    out->results = results;



#ifdef LOCAL_DEBUG

  f_dump_line(out, 0);

#endif

filter/f-inst.c

+4 −4
Original line number Diff line number Diff line
@@ -64,7 +64,7 @@ 
 *	m4_dnl	  ARG_ANY(num);				argument with no type check accessible by v1, v2, v3

 *	m4_dnl	  ARG_TYPE(num, type);			just declare the type of argument

 *	m4_dnl	  VARARG;				variable-length argument list; accessible by vv(i) and whati->varcount

 *	m4_dnl	  LINE(num, unused);			this argument has to be converted to its own f_line

 *	m4_dnl	  LINE(num, out);			this argument has to be converted to its own f_line

 *	m4_dnl	  SYMBOL;				symbol handed from config

 *	m4_dnl	  STATIC_ATTR;				static attribute definition

 *	m4_dnl	  DYNAMIC_ATTR;				dynamic attribute definition
@@ -298,7 +298,7 @@ 
    RESULT_TYPE(T_BOOL);



    if (v1.val.i)

      LINE(2,0);

      LINE(2,1);

    else

      RESULT_VAL(v1);

  }
@@ -308,7 +308,7 @@ 
    RESULT_TYPE(T_BOOL);



    if (!v1.val.i)

      LINE(2,0);

      LINE(2,1);

    else

      RESULT_VAL(v1);

  }
@@ -536,7 +536,7 @@ 
    if (v1.val.i)

      LINE(2,0);

    else

      LINE(3,1);

      LINE(3,0);

  }



  INST(FI_PRINT, 0, 0) {

filter/f-inst.h

+4 −3
Original line number Diff line number Diff line
@@ -46,14 +46,15 @@ struct f_line { 
  uint len;				/* Line length */

  u8 args;				/* Function: Args required */

  u8 vars;

  u8 results;				/* Results left on stack: cmd -> 0, term -> 1 */

  struct f_arg *arg_list;

  struct f_line_item items[0];		/* The items themselves */

};



/* Convert the f_inst infix tree to the f_line structures */

struct f_line *f_linearize_concat(const struct f_inst * const inst[], uint count);

static inline struct f_line *f_linearize(const struct f_inst *root)

{ return f_linearize_concat(&root, 1); }

struct f_line *f_linearize_concat(const struct f_inst * const inst[], uint count, uint results);

static inline struct f_line *f_linearize(const struct f_inst *root, uint results)

{ return f_linearize_concat(&root, 1, results); }



void f_dump_line(const struct f_line *, uint indent);

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