regcomp.c: Use regnode offsets during parsing

This changes the pattern parsing to use offsets from the first node in
the pattern program, rather than direct addresses of such nodes.  This
is in preparation for a later change in which more mallocs will be done
which will change those addresses, whereas the offsets will remain
constant.  Once the final program space is allocated, real addresses are
used as currently.  This limits the necessary changes to a few
functions.  Also, real addresses are used if they are constant across a
function; again this limits the changes.

Doing this introduces a new typedef for clarity 'regnode_offset' which
is not a pointer, but a count.  This necessitates changing a bunch of
things to use 0 instead of NULL to indicate an error.

A new boolean is also required to indicate if we are in the first or
second passes of the pattern.  And separate heap space is allocated for
scratch during the first pass.

1 files changed, 17 insertions, 17 deletions

diff --git a/embed.fnc b/embed.fnc
index c876b026c5..6ef9629132 100644
--- a/embed.fnc
+++ b/embed.fnc
@@ -2362,21 +2362,21 @@ Ep	|void	|regprop	|NULLOK const regexp *prog|NN SV* sv|NN const regnode* o|NULLO
 Ep	|int	|re_printf	|NN const char *fmt|...
 #endif
 #if defined(PERL_IN_REGCOMP_C)
-Es	|regnode*|reg		|NN RExC_state_t *pRExC_state \
+Es	|regnode_offset|reg	|NN RExC_state_t *pRExC_state \
 				|I32 paren|NN I32 *flagp|U32 depth
-Es	|regnode*|regnode_guts	|NN RExC_state_t *pRExC_state              \
+Es	|regnode_offset|regnode_guts|NN RExC_state_t *pRExC_state          \
 				|const U8 op				   \
 				|const STRLEN extra_len			   \
 				|NN const char* const name
-Es	|regnode*|reganode	|NN RExC_state_t *pRExC_state|U8 op \
+Es	|regnode_offset|reganode|NN RExC_state_t *pRExC_state|U8 op \
 				|U32 arg
-Es	|regnode*|reg2Lanode	|NN RExC_state_t *pRExC_state		   \
+Es	|regnode_offset|reg2Lanode|NN RExC_state_t *pRExC_state		   \
 				|const U8 op				   \
 				|const U32 arg1				   \
 				|const I32 arg2
-Es	|regnode*|regatom	|NN RExC_state_t *pRExC_state \
+Es	|regnode_offset|regatom	|NN RExC_state_t *pRExC_state \
 				|NN I32 *flagp|U32 depth
-Es	|regnode*|regbranch	|NN RExC_state_t *pRExC_state \
+Es	|regnode_offset|regbranch	|NN RExC_state_t *pRExC_state \
 				|NN I32 *flagp|I32 first|U32 depth
 Es	|void	 |set_ANYOF_arg	|NN RExC_state_t* const pRExC_state \
 				|NN regnode* const node                    \
@@ -2392,7 +2392,7 @@ Es	|void	|output_or_return_posix_warnings			    \
 Es	|AV*	 |add_multi_match|NULLOK AV* multi_char_matches		    \
 				|NN SV* multi_string			    \
 				|const STRLEN cp_count
-Es	|regnode*|regclass	|NN RExC_state_t *pRExC_state                 \
+Es	|regnode_offset|regclass|NN RExC_state_t *pRExC_state                 \
 				|NN I32 *flagp|U32 depth|const bool stop_at_1 \
 				|bool allow_multi_fold                        \
 				|const bool silence_non_portable              \
@@ -2402,12 +2402,12 @@ Es	|regnode*|regclass	|NN RExC_state_t *pRExC_state                 \
 				|NULLOK AV** return_posix_warnings
 Es	|void|add_above_Latin1_folds|NN RExC_state_t *pRExC_state|const U8 cp \
 				|NN SV** invlist
-Ei	|regnode*|handle_named_backref|NN RExC_state_t *pRExC_state	    \
+Ei	|regnode_offset|handle_named_backref|NN RExC_state_t *pRExC_state   \
 				|NN I32 *flagp				    \
 				|NN char * parse_start			    \
 				|char ch
 EsnR	|unsigned int|regex_set_precedence|const U8 my_operator
-Es	|regnode*|handle_regex_sets|NN RExC_state_t *pRExC_state \
+Es	|regnode_offset|handle_regex_sets|NN RExC_state_t *pRExC_state \
 				|NULLOK SV ** return_invlist            \
 				|NN I32 *flagp|U32 depth                \
 				|NN char * const oregcomp_parse
@@ -2418,21 +2418,21 @@ Es	|void	|dump_regex_sets_structures				    \
 				|const IV fence|NN AV * fence_stack
 #endif
 Es	|void|parse_lparen_question_flags|NN RExC_state_t *pRExC_state
-Es	|regnode*|reg_node	|NN RExC_state_t *pRExC_state|U8 op
-Es	|regnode*|regpiece	|NN RExC_state_t *pRExC_state \
+Es	|regnode_offset|reg_node|NN RExC_state_t *pRExC_state|U8 op
+Es	|regnode_offset|regpiece|NN RExC_state_t *pRExC_state \
 				|NN I32 *flagp|U32 depth
 Es	|bool	|grok_bslash_N	|NN RExC_state_t *pRExC_state		    \
-				|NULLOK regnode** nodep			    \
+				|NULLOK regnode_offset* nodep		    \
 				|NULLOK UV *code_point_p		    \
 				|NULLOK int* cp_count			    \
 				|NN I32 *flagp				    \
 				|const bool strict			    \
 				|const U32 depth
 Es	|void	|reginsert	|NN RExC_state_t *pRExC_state \
-				|U8 op|NN regnode *operand|U32 depth
+				|U8 op|regnode_offset operand|U32 depth
 Es	|void	|regtail	|NN RExC_state_t * pRExC_state		    \
-				|NN const regnode * const p		    \
-				|NN const regnode * const val		    \
+				|NN const regnode_offset p		    \
+				|NN const regnode_offset val		    \
 				|const U32 depth
 Es	|SV *	|reg_scan_name	|NN RExC_state_t *pRExC_state \
 				|U32 flags
@@ -2441,7 +2441,7 @@ Es	|U32	|join_exact	|NN RExC_state_t *pRExC_state \
 				|NN bool *unfolded_multi_char          \
 				|U32 flags|NULLOK regnode *val|U32 depth
 Ei	|void   |alloc_maybe_populate_EXACT|NN RExC_state_t *pRExC_state \
-				|NN regnode *node|NN I32 *flagp|STRLEN len \
+				|NN regnode_offset node|NN I32 *flagp|STRLEN len \
 				|UV code_point|bool downgradable
 Ein	|U8   |compute_EXACTish|NN RExC_state_t *pRExC_state
 Es	|void	|nextchar	|NN RExC_state_t *pRExC_state
@@ -2553,7 +2553,7 @@ Es	|void	|dump_trie_interim_table|NN const struct _reg_trie_data *trie\
 				|NULLOK HV* widecharmap|NN AV *revcharmap\
 				|U32 next_alloc|U32 depth
 Es	|U8	|regtail_study	|NN RExC_state_t *pRExC_state \
-				|NN regnode *p|NN const regnode *val|U32 depth
+				|NN regnode_offset p|NN const regnode_offset val|U32 depth
 #  endif
 #endif