Create a lookup table for magic vtables from magic type, PL_magic_data.

Use it to eliminate the large switch statement in Perl_sv_magic().

As the table needs to be keyed on magic type, which is expressed as C character
constants, the order depends on the compiler's character set. Frustratingly,
EBCDIC variants don't agree on the code points for '~' and ']', which we use
here. Instead of having (at least) 4 tables, get the local runtime to sort the
table for us. Hence the regen script writes out the (unsorted) mg_raw.h, which
generate_uudmap sorts to generate mg_data.h

1 files changed, 90 insertions, 0 deletions

diff --git a/mg_raw.h b/mg_raw.h
new file mode 100644
index 0000000000..363e189b18
--- /dev/null
+++ b/mg_raw.h
@@ -0,0 +1,90 @@
+/* -*- buffer-read-only: t -*-
+ *
+ *    mg_raw.h
+ * !!!!!!!   DO NOT EDIT THIS FILE   !!!!!!!
+ * This file is built by regen/mg_vtable.pl.
+ * Any changes made here will be lost!
+ */
+
+    { '\0', "want_vtbl_sv",
+      "/* sv '\\0' Special scalar variable */" },
+    { 'A', "want_vtbl_amagic",
+      "/* overload 'A' %OVERLOAD hash */" },
+    { 'a', "want_vtbl_amagicelem",
+      "/* overload_elem 'a' %OVERLOAD hash element */" },
+    { 'c', "want_vtbl_ovrld",
+      "/* overload_table 'c' Holds overload table (AMT) on stash */" },
+    { 'B', "want_vtbl_regexp",
+      "/* bm 'B' Boyer-Moore (fast string search) */" },
+    { 'D', "want_vtbl_regdata",
+      "/* regdata 'D' Regex match position data (@+ and @- vars) */" },
+    { 'd', "want_vtbl_regdatum",
+      "/* regdatum 'd' Regex match position data element */" },
+    { 'E', "want_vtbl_env",
+      "/* env 'E' %ENV hash */" },
+    { 'e', "want_vtbl_envelem",
+      "/* envelem 'e' %ENV hash element */" },
+    { 'f', "want_vtbl_regdata",
+      "/* fm 'f' Formline ('compiled' format) */" },
+    { 'g', "want_vtbl_mglob",
+      "/* regex_global 'g' m//g target / study()ed string */" },
+    { 'H', "want_vtbl_hints",
+      "/* hints 'H' %^H hash */" },
+    { 'h', "want_vtbl_hintselem",
+      "/* hintselem 'h' %^H hash element */" },
+    { 'I', "want_vtbl_isa",
+      "/* isa 'I' @ISA array */" },
+    { 'i', "want_vtbl_isaelem",
+      "/* isaelem 'i' @ISA array element */" },
+    { 'k', "want_vtbl_nkeys",
+      "/* nkeys 'k' scalar(keys()) lvalue */" },
+    { 'L', "want_vtbl_dbline",
+      "/* dbfile 'L' Debugger %_<filename */" },
+    { 'l', "magic_vtable_max",
+      "/* dbline 'l' Debugger %_<filename element */" },
+    { 'o', "want_vtbl_collxfrm",
+      "/* collxfrm 'o' Locale transformation */" },
+    { 'P', "want_vtbl_pack",
+      "/* tied 'P' Tied array or hash */" },
+    { 'p', "want_vtbl_packelem",
+      "/* tiedelem 'p' Tied array or hash element */" },
+    { 'q', "want_vtbl_packelem",
+      "/* tiedscalar 'q' Tied scalar or handle */" },
+    { 'r', "want_vtbl_regexp",
+      "/* qr 'r' precompiled qr// regex */" },
+    { 'S', "magic_vtable_max",
+      "/* sig 'S' %SIG hash */" },
+    { 's', "want_vtbl_sigelem",
+      "/* sigelem 's' %SIG hash element */" },
+    { 't', "want_vtbl_taint",
+      "/* taint 't' Taintedness */" },
+    { 'U', "want_vtbl_uvar",
+      "/* uvar 'U' Available for use by extensions */" },
+    { 'v', "want_vtbl_vec",
+      "/* vec 'v' vec() lvalue */" },
+    { 'V', "magic_vtable_max",
+      "/* vstring 'V' SV was vstring literal */" },
+    { 'w', "want_vtbl_utf8",
+      "/* utf8 'w' Cached UTF-8 information */" },
+    { 'x', "want_vtbl_substr",
+      "/* substr 'x' substr() lvalue */" },
+    { 'y', "want_vtbl_defelem",
+      "/* defelem 'y' Shadow \"foreach\" iterator variable / smart parameter vivification */" },
+    { '#', "want_vtbl_arylen",
+      "/* arylen '#' Array length ($#ary) */" },
+    { '.', "want_vtbl_pos",
+      "/* pos '.' pos() lvalue */" },
+    { '<', "want_vtbl_backref",
+      "/* backref '<' for weak ref data */" },
+    { ':', "magic_vtable_max",
+      "/* symtab ':' extra data for symbol tables */" },
+    { '%', "magic_vtable_max",
+      "/* rhash '%' extra data for restricted hashes */" },
+    { '@', "magic_vtable_max",
+      "/* arylen_p '@' to move arylen out of XPVAV */" },
+    { '~', "magic_vtable_max",
+      "/* ext '~' Available for use by extensions */" },
+    { ']', "magic_vtable_max",
+      "/* checkcall ']' inlining/mutation of call to this CV */" },
+
+/* ex: set ro: */