clean up macros.[ch]

There are some incompatible changes here, but only to interfaces that
were introduced earlier in 1.9, or interfaces which have been broken
since early in 1.9.

* libguile/_scm.h (SCM_OBJCODE_MINOR_VERSION): Bump, as the macro
  changes affect the interface that is called by psyntax-generated macro
  definitions.

* libguile/inline.h (scm_words): New function, allocates a variable
  number of contiguous scm_t_bits locations, with a given value in the
  0th word, and 0 in the rest of the words.

* libguile/macros.h: Rework interface to correspond more closely, and
  minimally, to the needs of memoize.c and psyntax.
  (SCM_ASSYNT, SCM_MACRO_TYPE_BITS, SCM_MACRO_TYPE_MASK)
  (SCM_F_MACRO_EXTENDED, SCM_MACROP, SCM_MACRO_TYPE)
  (SCM_MACRO_IS_EXTENDED, SCM_BUILTIN_MACRO_P, SCM_SYNCASE_MACRO_P)
  (SCM_MACRO_CODE, scm_tc16_macro): Remove CPP macros related to the
  representation of Scheme macros.
  (scm_i_make_primitive_macro): Renamed from scm_i_makbimacro.
  (scm_i_macro_primitive): New accessor so that memoize.c can get to the
  primitive syntax transformer.
  (scm_make_syncase_macro, scm_make_extended_syncase_macro)
  (scm_syncase_macro_type, scm_syncase_macro_binding): Removed these
  functions, replaced by make-syntax-transformer and its accessors.
  (scm_macro_binding): New accessor, the same as what
  scm_syncase_macro_binding was.

* libguile/macros.c: All representation details of syntax transformers
  are private to this file now.
  (macro_print): Print macros as #<syntax-transformer ...>, or
  #<primitive-syntax-transformer ...> if psyntax has not attached a
  transformer of its own.
  (scm_i_make_primitive_macro): Represent macros as 5-word smobs.
  (scm_make_syntax_transformer): New constructor for syntax transformers
  (macros), exported to scheme. Takes a name, and looks it up in the
  current module to determine the previous primitive transformer, if
  any.
  (scm_macro_type): Instead of returning 'builtin-macro!, etc, return
  the type as set by psyntax, or #f if it's a primitive.
  (scm_macro_name): Return the stored macro name.
  (scm_macro_transformer): Return the psyntax-set syntax transformer.
  Hacky, but should help introspection somewhat.

* libguile/memoize.c (memoize_env_ref_transformer): Use the new
  scm_i_macro_primitive, and adapt to other macro API changes.

* module/ice-9/psyntax.scm (put-global-definition-hook)
  (get-global-definition-hook, chi-install-global): Call (and generate
  calls to) the new macro constructors and accessors.

* module/ice-9/psyntax-pp.scm: Doubly regenerated.

* module/ice-9/debugging/traps.scm (trap-here): Comment out this
  definition and export, while it's not working.

1 files changed, 40 insertions, 1 deletions

diff --git a/libguile/inline.h b/libguile/inline.h
index 09a1b5a35..018e6c636 100644
--- a/libguile/inline.h
+++ b/libguile/inline.h
@@ -3,7 +3,7 @@
 #ifndef SCM_INLINE_H
 #define SCM_INLINE_H
 
-/* Copyright (C) 2001, 2002, 2003, 2004, 2006, 2008, 2009 Free Software Foundation, Inc.
+/* Copyright (C) 2001, 2002, 2003, 2004, 2006, 2008, 2009, 2010 Free Software Foundation, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public License
@@ -87,6 +87,9 @@ SCM_API SCM scm_double_cell (scm_t_bits car, scm_t_bits cbr,
 			     scm_t_bits ccr, scm_t_bits cdr);
 SCM_API SCM scm_immutable_double_cell (scm_t_bits car, scm_t_bits cbr,
 				       scm_t_bits ccr, scm_t_bits cdr);
+SCM_API SCM scm_words (scm_t_bits car, scm_t_uint16 n_words);
+/* no immutable words for now, would require initialization at the same time as
+   allocation */
 
 SCM_API SCM scm_array_handle_ref (scm_t_array_handle *h, ssize_t pos);
 SCM_API void scm_array_handle_set (scm_t_array_handle *h, ssize_t pos, SCM val);
@@ -241,6 +244,42 @@ scm_immutable_double_cell (scm_t_bits car, scm_t_bits cbr,
 SCM_C_EXTERN_INLINE
 #endif
 SCM
+scm_words (scm_t_bits car, scm_t_uint16 n_words)
+{
+  SCM z;
+
+  z = SCM_PACK ((scm_t_bits) (GC_MALLOC (sizeof (scm_t_bits) * n_words)));
+  SCM_GC_SET_CELL_WORD (z, 0, car);
+
+  /* FIXME: is the following concern even relevant with BDW-GC? */
+
+  /* When this function is inlined, it's possible that the last
+     SCM_GC_SET_CELL_WORD above will be adjacent to a following
+     initialization of z.  E.g., it occurred in scm_make_real.  GCC
+     from around version 3 (e.g., certainly 3.2) began taking
+     advantage of strict C aliasing rules which say that it's OK to
+     interchange the initialization above and the one below when the
+     pointer types appear to differ sufficiently.  We don't want that,
+     of course.  GCC allows this behaviour to be disabled with the
+     -fno-strict-aliasing option, but would also need to be supplied
+     by Guile users.  Instead, the following statements prevent the
+     reordering.
+   */
+#ifdef __GNUC__
+  __asm__ volatile ("" : : : "memory");
+#else
+  /* portable version, just in case any other compiler does the same
+     thing.  */
+  scm_remember_upto_here_1 (z);
+#endif
+
+  return z;
+}
+
+#ifndef SCM_INLINE_C_INCLUDING_INLINE_H
+SCM_C_EXTERN_INLINE
+#endif
+SCM
 scm_array_handle_ref (scm_t_array_handle *h, ssize_t p)
 {
   if (SCM_UNLIKELY (p < 0 && ((size_t)-p) > h->base))