Move bulk of pp_regcomp() into re_op_compile()

When called, pp_regcomp() is presented with a list of SVs on the stack.
Previously, it would perform (amongst other things):
  * overloading those SVs;
  * concatenating them;
  * detection of bare /$qr/;
  * detection of unchanged pattern;
optionally followed by a call to the built-in or an external regexp
compiler.

Since we want to avoid premature concatenation (so that we can handle
/$runtime(?{...})/), move all these activities from pp_regcomp() into
re_op_compile().

This makes re_op_compile() a bit cumbersome, with a large arg list,
but I haven't found any way of only moving only a subset of the above.

Note that a side-effect of this is that qr-overloading now works for all
regex compilations, not just those reached via pp_regcomp(); in particular
this now invokes the qr method rather than the "" method if available:
/(??{ $overloaded_object })/

1 files changed, 5 insertions, 2 deletions

diff --git a/embed.fnc b/embed.fnc
index 128cc68d8e..0fe55c6a5c 100644
--- a/embed.fnc
+++ b/embed.fnc
@@ -1058,8 +1058,11 @@ Ap	|void*	|regdupe_internal|NN REGEXP * const r|NN CLONE_PARAMS* param
 #endif
 p	|regexp_engine*|current_re_engine
 Ap	|REGEXP*|pregcomp	|NN SV * const pattern|const U32 flags
-p	|REGEXP*|re_op_compile	|NULLOK SV * const * const patternp \
-				|int pat_count|NULLOK OP *expr|U32 flags
+p	|REGEXP*|re_op_compile	|NULLOK SV ** const patternp \
+				|int pat_count|NULLOK OP *expr \
+				|NULLOK const regexp_engine* eng \
+				|NULLOK REGEXP *old_re|NULLOK int *is_bare_re \
+				|U32 flags
 Ap	|REGEXP*|re_compile	|NN SV * const pattern|U32 flags
 Ap	|char*	|re_intuit_start|NN REGEXP * const rx|NULLOK SV* sv|NN char* strpos \
 				|NN char* strend|const U32 flags \