* libguile/eval.c: Fix a comment.
(eval): Abstract out the variable memoization into a function,
scm_memoize_variable_access_x.
* libguile/memoize.c (memoized_tags): Fix a couple names.
(scm_memoize_variable_access_x): New internal function. Actually it's
public to Scheme, but we can't do much about that, because the new
evaluator will need it.
(scm_memoized_expression_typecode, scm_memoized_expression_data): New
accessors for memoized code, for Scheme.
(scm_memoized_typecode): Looks up the typecode for a symbol.
* libguile/eval.c: So, ladies & gents, a new evaluator. It's similar to
the old one, in that we memoize and then evaluate, but in this
incarnation, memoization of an expression happens before evaluation,
not lazily as the expression is evaluated. This makes the evaluation
itself much cleaner, in addition to being threadsafe. In addition,
since this C evaluator will in the future just serve to bootstrap the
Scheme evaluator, we don't have to pay much concern for debugging
conveniences. So the environment is just a list of values, and the
memoizer pre-computes where it's going to find each individual value
in the environment.
Interface changes are commented below, with eval.h.
(scm_evaluator_traps): No need to reset the debug mode after rnning te
traps thing. But really, the whole traps system needs some love.
* libguile/memoize.h:
* libguile/memoize.c: New memoizer, which runs before evaluation,
checking all syntax before evaluation begins. Significantly, no
debugging information is left for lexical variables, which is not so
great for interactive debugging; perhaps we should change this to have
a var list in the future as per the classic interpreters. But it's
quite fast, and the resulting code is quite good. Also note that it
doesn't produce ilocs, memoized code is a smob whose type is in the
first word of the smob itself.
* libguile/eval.h (scm_sym_and, scm_sym_begin, scm_sym_case)
(scm_sym_cond, scm_sym_define, scm_sym_do, scm_sym_if, scm_sym_lambda)
(scm_sym_let, scm_sym_letstar, scm_sym_letrec, scm_sym_quote)
(scm_sym_quasiquote, scm_sym_unquote, scm_sym_uq_splicing, scm_sym_at)
(scm_sym_atat, scm_sym_atapply, scm_sym_atcall_cc)
(scm_sym_at_call_with_values, scm_sym_delay, scm_sym_eval_when)
(scm_sym_arrow, scm_sym_else, scm_sym_apply, scm_sym_set_x)
(scm_sym_args): Remove public declaration of these symbols.
(scm_ilookup, scm_lookupcar, scm_eval_car, scm_eval_body)
(scm_eval_args, scm_i_eval_x, scm_i_eval): Remove public declaration
of these functions.
(scm_ceval, scm_deval, scm_ceval_ptr): Remove declarations of these
deprecated functions.
(scm_i_print_iloc, scm_i_print_isym, scm_i_unmemocopy_expr)
(scm_i_unmemocopy_body): Remove declarations of these internal
functions.
(scm_primitive_eval_x, scm_eval_x): Redefine as macros for their less
destructive siblings.
* libguile/Makefile.am: Add memoize.[ch] to the build.
* libguile/debug.h (scm_debug_mode_p, scm_check_entry_p)
(scm_check_apply_p, scm_check_exit_p, scm_check_memoize_p)
(scm_debug_eframe_size): Remove these vars that were tied to the old
evaluator's execution model.
(SCM_RESET_DEBUG_MODE): Remove, no more need for this.
(SCM_MEMOIZEDP, SCM_MEMOIZED_EXP, SCM_MEMOIZED_ENV): Remove macros
referring to old memoized code representation.
(scm_local_eval, scm_procedure_environment, scm_memoized_environment)
(scm_make_memoized, scm_memoized_p): Remove functions operating on old
memoized code representation.
(scm_memcons, scm_mem_to_proc, scm_proc_to_mem): Remove debug-only
code for old evaluator.
* libguile/debug.c: Remove code to correspond with debug.h removals.
(scm_debug_options): No need to set the debug mode or frame limit
here, as we don't have C stack limits any more. Perhaps this is a bug,
but as long as we can compile eval.scm, we should be fine.
* libguile/init.c (scm_i_init_guile): Init memoize.c.
* libguile/modules.c (scm_top_level_env, scm_env_top_level)
(scm_env_module, scm_system_module_env_p): Remove these functions.
* libguile/print.c (iprin1): No more need to handle isyms. Adapt to new
form of interpreted procedures.
* libguile/procprop.c (scm_i_procedure_arity): Adapt to new form of
interpreted procedures.
* libguile/procs.c (scm_thunk_p): Adapt to new form of interpreted
procedures.
* libguile/procs.h (SCM_CLOSURE_FORMALS): Removed, this exists no more.
(SCM_CLOSURE_NUM_REQUIRED_ARGS, SCM_CLOSURE_HAS_REST_ARGS): New
accessors.
* libguile/srcprop.c (scm_source_properties, scm_source_property)
(scm_set_source_property_x): Remove special cases for memoized code.
* libguile/stacks.c (read_frame): Remove a source-property case for
interpreted code.
(NEXT_FRAME): Remove a case that I don't fully understand, that seems
to be designed to skip over apply frames. Will be obsolete in the
futures.
(read_frames): Default source value for interpreted frames to #f.
(narrow_stack): Don't pay attention to the system_module thing.
* libguile/tags.h: Remove isyms and ilocs. Whee!
* libguile/validate.h (SCM_VALIDATE_MEMOIZED): Fix to use the new
MEMOIZED_P formulation.
* module/ice-9/psyntax-pp.scm (do, quasiquote, case): Adapt for these no
longer being primitive macros.
* module/ice-9/boot-9.scm: Whitespace change, but just a poke to force a
rebuild due to and/or/cond/... not being primitives any more.
* module/ice-9/deprecated.scm (unmemoize-expr): Deprecate, it's
unmemoize-expression now.
* test-suite/tests/eval.test ("define set procedure-name"): XFAIL a
couple of tests here; I don't know what to do about them. I reckon the
expander should ensure that defined values are named.
* test-suite/tests/chars.test ("basic char handling"): Fix expected
exception when trying to apply a char.
