ast.c revision 4fd606d1f5abe38e1f42c38de1d2e895166bd0f4
/* Abstract syntax tree manipulation functions
*
* SOFTWARE RIGHTS
*
* We reserve no LEGAL rights to the Purdue Compiler Construction Tool
* Set (PCCTS) -- PCCTS is in the public domain. An individual or
* company may do whatever they wish with source code distributed with
* PCCTS or the code generated by PCCTS, including the incorporation of
* PCCTS, or its output, into commerical software.
*
* We encourage users to develop software with PCCTS. However, we do ask
* that credit is given to us for developing PCCTS. By "credit",
* we mean that if you incorporate our source code into one of your
* programs (commercial product, research project, or otherwise) that you
* acknowledge this fact somewhere in the documentation, research report,
* etc... If you like PCCTS and have developed a nice tool with the
* output, please mention that you developed it using PCCTS. In
* addition, we ask that this header remain intact in our source code.
* As long as these guidelines are kept, we expect to continue enhancing
* this system and expect to make other tools available as they are
* completed.
*
* ANTLR 1.33
* Terence Parr
* Parr Research Corporation
* with Purdue University and AHPCRC, University of Minnesota
* 1989-2000
*/
#include "pcctscfg.h"
#ifdef PCCTS_USE_STDARG
#include "pccts_stdarg.h"
#else
#include <varargs.h>
#endif
/* ensure that tree manipulation variables are current after a rule
* reference
*/
void
#ifdef __USE_PROTOS
#else
#endif
{
}
AST *
#ifdef __USE_PROTOS
zzastnew(void)
#else
zzastnew()
#endif
{
return p;
}
/* add a child node to the current sibling list */
void
#ifdef __USE_PROTOS
#else
#endif
{
AST *n;
n = zzastnew();
#ifdef DEMAND_LOOK
#else
#endif
zzastPush( n );
else {
*_sibling = n;
}
*_tail = n;
}
}
/* make a new AST node. Make the newly-created
* node the root for the current sibling list. If a root node already
* exists, make the newly-created node the root of the current root.
*/
void
#ifdef __USE_PROTOS
#else
#endif
{
AST *n;
n = zzastnew();
#ifdef DEMAND_LOOK
#else
#endif
zzastPush( n );
*_root = n;
}
}
/* Apply function to root then each sibling
* example: print tree in child-sibling LISP-format (AST has token field)
*
* void show(tree)
* AST *tree;
* {
* if ( tree == NULL ) return;
* printf(" %s", zztokens[tree->token]);
* }
*
* void before() { printf(" ("); }
* void after() { printf(" )"); }
*
* LISPdump() { zzpre_ast(tree, show, before, after); }
*
*/
void
#ifdef __USE_PROTOS
#else
void (*func)(), /* apply this to each tree node */
(*before)(), /* apply this to root of subtree before preordering it */
(*after)(); /* apply this to root of subtree after preordering it */
#endif
{
{
}
}
/* free all AST nodes in tree; apply func to each before freeing */
#if 0
////void
////#ifdef __USE_PROTOS
////zzfree_ast(AST *tree)
////#else
////zzfree_ast(tree)
////AST *tree;
////#endif
////{
//// if ( tree == NULL ) return;
//// zzfree_ast( tree->down );
//// zzfree_ast( tree->right );
//// zztfree( tree );
////}
#endif
/*
MR19 Optimize freeing of the following structure to limit recursion
SAKAI Kiyotaka (ksakai@isr.co.jp)
*/
/*
NULL o
/ \
NULL o
/ \
NULL NULL
*/
/*
MR21 Another refinement to replace recursion with iteration
NAKAJIMA Mutsuki (muc@isr.co.jp).
*/
void
#ifdef __USE_PROTOS
#else
#endif
{
return;
}
} else {
}
}
}
}
/* build a tree (root child1 child2 ... NULL)
* If root is NULL, simply make the children siblings and return ptr
* to 1st sibling (child1). If root is not single node, return NULL.
*
* Siblings that are actually siblins lists themselves are handled
* correctly. For example #( NULL, #( NULL, A, B, C), D) results
* in the tree ( NULL A B C D ).
*
* Requires at least two parameters with the last one being NULL. If
* both are NULL, return NULL.
*/
#ifdef PCCTS_USE_STDARG
#else
#endif
{
#ifdef PCCTS_USE_STDARG
#else
#endif
{
}
return root;
}
/* tree duplicate */
AST *
#ifdef __USE_PROTOS
#else
zzdup_ast(t)
AST *t;
#endif
{
AST *u;
u = zzastnew();
*u = *t;
#ifdef zzAST_DOUBLE
#endif
#ifdef zzAST_DOUBLE
#endif
return u;
}
void
#ifdef __USE_PROTOS
#else
zztfree(t)
AST *t;
#endif
{
#ifdef zzd_ast
zzd_ast( t );
#endif
free( t );
}
#ifdef zzAST_DOUBLE
/*
* Set the 'up', and 'left' pointers of all nodes in 't'.
* Initial call is double_link(your_tree, NULL, NULL).
*/
void
#ifdef __USE_PROTOS
#else
#endif
{
if ( t==NULL ) return;
}
#endif