* libguile/vm.c (vm_error_kwargs_invalid_keyword,
vm_error_kwargs_unrecognized_keyword): Add parameter. Pass it
enclosed in a list as the last argument to `scm_error_scm'.
* libguile/vm-i-system.c (bind_kwargs): Adjust accordingly.
* libguile/eval.c (error_invalid_keyword, error_unrecognized_keyword):
Add parameter.
(prepare_boot_closure_env_for_apply): Adjust accordingly.
* module/ice-9/eval.scm (primitive-eval): Likewise.
* libguile/error.c (scm_error_scm): Mention `keyword-argument-error' in
docstring.
* module/ice-9/boot-9.scm (keyword-error-printer): New procedure; use it.
* test-suite/tests/optargs.test (c&e, with-test-prefix/c&e): Remove.
("define*")["unrecognized keyword"]: Test the value passed along the
`keyword-argument-error' exception.
["invalid keyword"]: New test.
* doc/ref/api-control.texi (Error Reporting): Update `scm-error'
description.
* libguile/vm-engine.c (rtl_vm_engine): Add new VM.
(vm_engine): Add support for calling RTL programs.
* libguile/tags.h (scm_tc7_rtl_program): New type for procedures that
run on the new VM.
* libguile/evalext.c (scm_self_evaluating_p):
* libguile/goops.c (scm_class_of):
* libguile/print.c (iprin1):
* libguile/procprop.c (scm_i_procedure_arity):
* libguile/procs.c (scm_procedure_p): Add hooks for the new tc7.
* libguile/programs.h:
* libguile/programs.c (scm_make_rtl_program, scm_i_rtl_program_print)
(scm_rtl_program_p, scm_rtl_program_code):
* module/system/vm/program.scm: Add constructors and accessors for the
new "RTL programs".
* libguile/vm.c (rtl_boot_continuation): Define a boot program.
(rtl_apply, rtl_values): New static RTL programs.
* libguile/frames.c (scm_frame_num_locals): Adapt for frames of RTL
programs.
* libguile/frames.h: Add description of RTL frames.
* libguile/Makefile.am: Add rules to generate vm-operations.h.
* .gitignore: Ignore vm-operations.h.
* module/system/vm/instruction.scm:
* libguile/instructions.c:
* libguile/instructions.h: Use vm-operations.h to define enumerated
values for the new RTL opcodes. Define some helper macros to pack and
unpack 32-bit instruction words.
(rtl-instruction-list): New function, exported by (system vm
instruction).
* libguile/objcodes.c: Wire up the bits needed to detect the new RTL
bytecode and load it, as appropriate.
* doc/ref/api-debug.texi (VM Hooks): Update documentation.
* libguile/vm.c (vm_dispatch_hook):
* libguile/vm-engine.c: Rework the hook machinery so that they can
receive an arbitrary number of arguments. The return and abort
hooks will pass the values that they return to their continuations.
(vm_engine): Adapt to ABORT_CONTINUATION_HOOK change.
* libguile/vm-i-system.c (return, return/values): Adapt to
POP_CONTINUATION_HOOK change.
* module/system/vm/frame.scm (frame-return-values): Remove. The
pop-continuation-hook will pass the values directly.
* module/system/vm/trace.scm (print-return):
(trace-calls-to-procedure):
(trace-calls-in-procedure): Update to receive return values
directly.
* module/system/vm/traps.scm (trap-in-procedure)
(trap-in-dynamic-extent): Ignore return values.
(trap-frame-finish, trap-calls-in-dynamic-extent)
(trap-calls-to-procedure): Pass return values to the handlers.
* libguile/vm-engine.c: Remove the ability for the VM to check object
access, free variable access, and the ip. They were off by default.
Since they will be different in the RTL VM, their presence is just
making things confusing.
* libguile/vm.c: Remove corresponding error helpers.
* libguile/vm.c (initialize_default_stack_size): New helper.
(scm_bootstrap_vm): Call initialize_default_stack_size.
* doc/ref/guile-invoke.texi (Environment Variables): Add docs.
Based on a patch by Stefan Israelsson Tampe.
* libguile/objcodes.c: Change to expect objcode on disk to be embedded
in ELF instead of having the funky cookie.
(to_native_order): Use already existing SCM_BYTE_ORDER style byte
order instead of chars.
(bytecode_to_objcode): No need for word_size arg.
(scm_bytecode_to_objcode, scm_objcode_to_bytecode): Take optional
endianness arg instead of sometimes using target-endianness.
(scm_load_objcode, scm_write_objcode, scm_bytecode_to_native_objcode):
Remove.
* libguile/objcodes.h: Adapt.
* libguile/vm.c (scm_load_compiled_with_vm): Use
scm_load_thunk_from_file.
(make_boot_program): Adapt to use scm_bytecode_to_objcode with
endianness arg.
* module/Makefile.am (OBJCODE_LANG_SOURCES): Add (language objcode
elf).
* module/language/objcode/elf.scm: New module, embeds objcode in ELF.
* module/language/bytecode/spec.scm (compile-objcode):
(decompile-objcode): Use (target-endianness).
* module/language/objcode/spec.scm: use (language objcode elf) for
write-objcode.
* module/scripts/disassemble.scm (disassemble):
* module/system/repl/command.scm (disassemble-file): Use
load-thunk-from-file.
* module/system/vm/objcode.scm: Remove load-objcode and write-objcode.
* test-suite/tests/asm-to-bytecode.test (test-target): Adapt to the new
ELF world.
This commit removes code that was newly deprecated in stable-2.0.
Conflicts:
libguile/deprecated.c
libguile/deprecated.h
libguile/modules.c
module/ice-9/boot-9.scm
module/ice-9/deprecated.scm
* libguile/deprecated.h:
* libguile/deprecated.c (scm_sym2var): Deprecate this function.
* libguile/modules.h:
* libguile/modules.c (scm_module_ensure_local_variable): New public
function, replacing scm_sym2var with a true definep, without going
through eval closures (which are deprecated).
(scm_current_module): Rework to do something sensible before modules
are booted.
(scm_module_lookup, scm_lookup): Refactor to use scm_module_variable.
(scm_module_define, scm_define): Refactor to use
scm_module_ensure_local_variable.
* libguile/vm-i-system.c (define!): Use scm_define.
* libguile/vm.c (resolve_variable): Use scm_module_lookup.
* libguile/macros.c (scm_make_syntax_transformer): Use
scm_module_variable.
* libguile/gdbint.c (gdb_binding): Use scm_define.
* doc/ref/api-modules.texi (Accessing Modules from C): Add docs for
scm_module_ensure_local_variable.
* libguile/vm.c: Remove a check for modules being booted. If the module
passed in is true, that is guaranteed to have been the case. Passes a
fresh bootstrap.
* libguile/frames.c (scm_frame_instruction_pointer):
* module/system/vm/frame.scm (frame-bindings):
(frame-next-source, frame-call-representation): Fix a few locations
that thought that the frame-procedure will always be a VM
procedure. This will not not be the case when traversing the stack of
an application of a non-procedure.
* libguile/vm-i-system.c (call, tail-call, mv-call): Instead of
special-casing structs and smobs at these call sites, just set up the
stack, and jump to a generic apply loop if the proc is not a program.
* libguile/vm-engine.c: The generic apply loop is here. Also, the boot
program is now simply a boot continuation, and can handle any number
of arguments.
* libguile/vm.c (make_boot_program): Update the code that makes the boot
continuation.
* libguile/vm.c:
(vm_error):
(vm_error_bad_instruction):
(vm_error_unbound):
(vm_error_unbound_fluid):
(vm_error_not_a_variable):
(vm_error_not_a_thunk):
(vm_error_apply_to_non_list):
(vm_error_kwargs_length_not_even):
(vm_error_kwargs_invalid_keyword):
(vm_error_kwargs_unrecognized_keyword):
(vm_error_too_many_args):
(vm_error_wrong_num_args):
(vm_error_wrong_type_apply):
(vm_error_stack_overflow):
(vm_error_stack_underflow):
(vm_error_improper_list):
(vm_error_not_a_pair):
(vm_error_not_a_bytevector):
(vm_error_not_a_struct):
(vm_error_no_values):
(vm_error_not_enough_values):
(vm_error_continuation_not_rewindable):
(vm_error_bad_wide_string_length):
(vm_error_invalid_address):
(vm_error_object):
(vm_error_free_variable): New internal helpers, implementing VM error
handling.
* libguile/vm-engine.h (VM_ASSERT): New helper macro.
(ASSERT, CHECK_OBJECT, CHECK_FREE_VARIABLE):
(PRE_CHECK_UNDERFLOW, PUSH_LIST): Use the new helper.
* libguile/vm-i-loader.c:
* libguile/vm-i-scheme.c:
* libguile/vm-i-system.c: Use VM_ASSERT and the out-of-line error
handlers.
* libguile/vm-engine.c (vm_engine): Remove inline error handlers, and
remove a couple of local vars. Use VM_ASSERT. Have halt handle the
return itself.
* libguile/vm.c (prepare_smob_call): New helper. Now, instead of making
a per-smob trampoline, we will shuffle the smob into the args and use
a gsubr. This prevents a memory leak in which the trampolines, which
were values in a weak-key table, were preventing the smobs from being
collected.
* libguile/vm-i-system.c (call, tail-call, mv-call): Adapt to new smob
application mechanism.
(smob-call): Remove this instruction.
* libguile/smob.h (scm_smob_descriptor): Rename apply_trampoline_objcode
to apply_trampoline.
* libguile/smob.c: Remove our own objcode trampolines in favor of using
scm_c_make_gsubr.
(scm_smob_prehistory): No more trampoline weak map.
* libguile/procprop.c (scm_i_procedure_arity): Adapt to applicable smob
representation change.
* libguile/vm.c (prepare_smob_call): New helper. Now, instead of making
a per-smob trampoline, we will shuffle the smob into the args and use
a gsubr. This prevents a memory leak in which the trampolines, which
were values in a weak-key table, were preventing the smobs from being
collected.
* libguile/vm-i-system.c (call, tail-call, mv-call): Adapt to new smob
application mechanism.
(smob-call): Remove this instruction.
* libguile/smob.h (scm_smob_descriptor): Rename apply_trampoline_objcode
to apply_trampoline.
* libguile/smob.c: Remove our own objcode trampolines in favor of using
scm_c_make_gsubr.
(scm_smob_prehistory): No more trampoline weak map.
* libguile/procprop.c (scm_i_procedure_arity): Adapt to applicable smob
representation change.
* libguile/control.h: Remove scm_t_prompt_registers and
scm_c_make_prompt_registers.
(scm_c_abort): Take a pointer to a jmpbuf instead of a cookie. It
will serve the same purpose.
* libguile/control.c (reify_partial_continuation, scm_at_abort): Adapt
to new prompt representation.
* libguile/dynstack.h:
* libguile/dynstack.c (scm_dynstack_push_prompt): Prompts now have 5
words instead of 2, as they now push the fp, sp, ip, and jmpbuf on the
stack separately. This avoids allocation.
(scm_dynstack_find_prompt): Likewise, add return values for fp, sp,
etc.
(scm_dynstack_wind_prompt): Replaces scm_dynstack_relocate_prompt.
* libguile/eval.c (eval):
* libguile/stacks.c (find_prompt):
* libguile/throw.c (pre_init_catch): Adapt to the new prompt mechanism.
* libguile/vm-engine.c (vm_engine): Setjmp an on-stack jmpbuf every time
the VM enters. We can then re-use that jmpbuf for all prompts in that
invocation.
* libguile/vm-i-system.c (partial_cont_call): Adapt to change in prompt
representation. We don't need to wind here any more, since we pass in
the prompt's jmpbuf.
(prompt): Adapt to scm_dynstack_push_prompt change.
(abort): Adapt to vm_abort change.
* libguile/vm.h (struct scm_vm): No more cookie.
* libguile/vm.c (vm_abort): Adapt to scm_c_abort change.
(vm_reinstate_partial_continuation): Rewind the dynamic stack here,
now that we do have a valid jmpbuf.
(make_vm): No need to initialize a cookie.
* libguile/dynstack.h:
* libguile/dynstack.c: New files, implementing the dynamic stack as a
true stack instead of a linked list. This lowers the cost of
dynwinds: frames, winders, prompts, with-fluids, and dynamic-wind.
For the most part, we allocate these items directly on the stack.
* libguile/dynwinds.h:
* libguile/dynwinds.c: Adapt all manipulators of the wind stack to use
interfaces from dynstack.c. Remove heap-allocated winder and frame
object types.
(scm_dowinds, scm_i_dowinds): Remove these. The first was exported,
but it was not a public interface.
* libguile/continuations.c:
* libguile/continuations.h (scm_t_contregs): Continuation objects
reference scm_t_dynstack* values now. Adapt to the new interfaces.
* libguile/control.c:
* libguile/control.h: There is no longer a scm_tc7_prompt kind of object
that can be allocated on the heap. Instead, the prompt flags, key,
and registers are pushed on the dynwind stack. (The registers are
still on the heap.) Also, since the vm_cont will reference the
dynwinds, make the partial continuation stub take just one extra arg,
instead of storing the intwinds separately in the object table.
* libguile/fluids.c:
* libguile/fluids.h: No more with-fluids objects; instead, the fluids go
on the dynstack. The values still have to be on the heap, though.
(scm_prepare_fluids, scm_swap_fluids): New internal functions,
replacing scm_i_make_with_fluids and scm_i_swap_with_fluids.
* libguile/print.c: Remove prompt and with-fluids printers.
* libguile/tags.h: Revert prompt and with-fluids tc7 values to what they
were before they were allocated.
* libguile/vm-i-system.c (partial_cont_call): Just pop the vmcont, the
intwinds will not be passed as a second arg. Rewind the dynamic stack
from within the VM, so that any rewinder sees valid prompt entries.
(call_cc, tail_call_cc): Adapt to pass the dynstack to
scm_i_vm_capture_stack.
(prompt, wind, unwind, wind_fluids, unwind_fluids): Adapt to the new
interfaces.
* libguile/vm.h (scm_i_capture_current_stack): Rename from
scm_i_vm_capture_continuation.
(scm_i_vm_capture_stack): Take a dynstack as an argument.
* libguile/vm.c (vm_reinstate_partial_continuation): Don't wind here, as
that could result in winders seeing invalid prompts.
* libguile/eval.c:
* libguile/root.c:
* libguile/stacks.c:
* libguile/threads.c:
* libguile/threads.h:
* libguile/throw.c: Adapt other users of dynwinds to use the dynstack.
* libguile/frames.c: Add compile-time assertions on the layout of
`struct scm_vm_frame'.
(RELOC): Parenthesize and type VAL.
* libguile/frames.h (SCM_FRAME_STRUCT): Write in terms of
`SCM_FRAME_DATA_ADDRESS'.
(SCM_FRAME_DATA_ADDRESS): Parenthesize and type FP.
(SCM_FRAME_SET_DYNAMIC_LINK): Write in terms of
`SCM_FRAME_DYNAMIC_LINK'.
* libguile/vm.c (RELOC): Parenthesize and type SCM_P.
* module/system/base/target.scm (%target-endianness, %target-word-size):
New fluids.
(%native-word-size): New variable.
(with-target): Set these fluids.
(cpu-endianness, cpu-word-size, triplet-cpu, triplet-vendor,
triplet-os): New procedures.
(target-cpu, target-vendor, target-os): Use them.
(target-endianness, target-word-size): Refer to the corresponding
fluid.
* libguile/objcodes.c (target_endianness_var, target_word_size_var): New
global variables.
(NATIVE_ENDIANNESS): New macro.
(target_endianness, target_word_size, to_native_order): New functions.
(make_objcode_from_file): Use `scm_bytecode_to_native_objcode' instead
of `scm_bytecode_to_objcode'.
(bytecode_to_objcode): New function, based on `scm_bytecode_to_objcode',
with the addition of an `endianness' and `word_size' parameters.
(scm_bytecode_to_objcode): Use it.
(scm_bytecode_to_native_objcode): New function.
(scm_write_objcode): Use `target_word_size' and `target_endianness'.
Convert OBJCODE's len and meta-len to native byte order.
(scm_init_objcodes): Initialize `target_endianness_var' and
`target_word_size_var'.
* libguile/objcodes.h (scm_bytecode_to_native_objcode): New declaration.
* libguile/vm.c (really_make_boot_program): Use
`scm_bytecode_to_native_objcode' instead of `scm_bytecode_to_objcode'.
* test-suite/tests/asm-to-bytecode.test (%objcode-cookie-size): New
variable.
(test-target): New procedure.
("cross-compilation"): Add `test-target' calls and the "unknown
target" test.
* libguile/ports.c (scm_putc, scm_puts):
* libguile/ports.h (scm_putc_unlocked, scm_puts_unlocked): Separate into
_unlocked and locked variants. Change all callers to use the
_unlocked versions.
* libguile/tags.h (SCM_UNPACK_POINTER, SCM_PACK_POINTER): New macros.
The old SCM2PTR and PTR2SCM were defined in such a way that
round-tripping through a pointer could lose precision, even in the
case in which you weren't interested in actually dereferencing the
pointer, it was simply that you needed to plumb a SCM through APIs
that take pointers. These new macros are more like SCM_PACK and
SCM_UNPACK, but for pointer types. The bit representation of the
pointer should be the same as the scm_t_bits representation.
* libguile/gc.h (PTR2SCM, SCM2PTR): Remove support for (old) UNICOS
pointers. We are going to try tagging the SCM object itself in the
future, and I don't think that keeping this support is worth its
cost. It probably doesn't work anyway.
* libguile/backtrace.c:
* libguile/bytevectors.c:
* libguile/continuations.c:
* libguile/fluids.c:
* libguile/foreign.c:
* libguile/gc.h:
* libguile/guardians.c:
* libguile/hashtab.c:
* libguile/load.c:
* libguile/numbers.c:
* libguile/ports.c:
* libguile/smob.c:
* libguile/strings.c:
* libguile/symbols.c:
* libguile/vm.c:
* libguile/weak-set.c:
* libguile/weak-table.c:
* libguile/weak-vector.c: Update many sites to use the new macros.
* libguile/bytevectors.h:
* libguile/bytevectors.c (scm_c_take_gc_bytevector): Rename this
internal function, from scm_c_take_bytevector. This indicates that
unlike the other scm_take_* functions, this one takes GC-managed
memory.
* libguile/objcodes.c (scm_objcode_to_bytecode):
* libguile/vm.c (really_make_boot_program): Use
scm_gc_malloc_pointerless, not scm_malloc. Thanks to Stefan
Israelsson Tampe!
* libguile/r6rs-ports.c:
* libguile/strings.c: Adapt to renames.
* libguile/bytevectors.h (SCM_BYTEVECTOR_HEADER_SIZE): Bump, giving
bytevectors another word: a parent pointer. Will allow for
sub-bytevectors and efficient mmap bindings.
* libguile/bytevectors.c (make_bytevector):
(make_bytevector_from_buffer): Init parent to #f.
(scm_c_take_bytevector, scm_c_take_typed_bytevector): Another
argument, the parent, which gets set in the bytevector.
* libguile/foreign.c (scm_pointer_to_bytevector): Use the parent field
instead of registering a weak reference from bytevector to foreign
pointer.
* libguile/objcodes.c (scm_objcode_to_bytecode): Use the parent field to
avoid copying the objcode.
* libguile/srfi-4.c (DEFINE_SRFI_4_C_FUNCS):
* libguile/strings.c (scm_from_stringn):
* libguile/vm.c (really_make_boot_program):
* libguile/r6rs-ports.c (scm_get_bytevector_some)
(scm_get_bytevector_all, bytevector_output_port_procedure): Set the
parent to #f.
* libguile/bytevectors.c:
* libguile/eval.c:
* libguile/goops.c:
* libguile/i18n.c:
* libguile/load.c:
* libguile/memoize.c:
* libguile/modules.c:
* libguile/ports.c:
* libguile/print.c:
* libguile/procs.c:
* libguile/programs.c:
* libguile/read.c:
* libguile/script.c:
* libguile/srfi-14.c:
* libguile/stacks.c:
* libguile/strings.c:
* libguile/throw.c:
* libguile/vm.c: Use scm_from_latin1_symboln to make symbols from string
literals, because they aren't in the user's locale -- they are in
ASCII, and we can optimize this case.
* libguile/vm-i-loader.c: Also use scm_from_latin1_symboln when loading
narrow symbols.
* libguile/debug.c:
* libguile/eval.c:
* libguile/frames.c:
* libguile/objcodes.c:
* libguile/print.c:
* libguile/programs.c:
* libguile/read.c:
* libguile/struct.c:
* libguile/vm.c: Fix a number of instances in which we assumed we could
fit a pointer into a long.
* libguile/vm-i-scheme.c (INUM_MAX, INUM_MIN): New macros.
(add1, sub1): Add/subtract without untagging the operand. This leads
to a 44% run time improvement compared to the previous
implementation.
* libguile/vm.c: Include <stdint.h>.
* test-suite/tests/numbers.test ("1+", "1-"): Add tests for
MOST-POSITIVE-FIXNUM, resp. MOST-NEGATIVE-FIXNUM, for 32-bit and
34-bit values thereof.
* benchmark-suite/benchmarks/arithmetic.bm: New file.
* benchmark-suite/Makefile.am (SCM_BENCHMARKS): Add it.
* libguile/stackchk.h: Include private-options.h if we are building
guile.
* libguile/vm.c (scm_c_vm_run): Check for C stack overflow before
entering the engine.
* libguile/script.c (scm_compile_shell_switches): Select the debugging
VM in the cases that we previously would select deval -- when running
interactively without --no-debug, or otherwise with --debug.
* libguile/vm.c: Default to the regular engine.
(scm_c_set_vm_engine_x): Remove requirement for the VM to have no
pending computations.
* libguile/vm.h (scm_c_vm_run): Make internal.
* libguile/vm.c (vm_default_engine): New static global variable.
(make_vm): Set vp->engine based on
(scm_vm_apply): Remove in favor of call-with-vm.
(scm_thread_vm, scm_set_thread_vm_x): Remove these, as they did not
have a well-defined meaning, and were dangerous to call on other
threads.
(scm_the_vm): Reinstate previous definition.
(symbol_to_vm_engine, vm_engine_to_symbol)
(vm_has_pending_computation): New helpers.
(scm_vm_engine, scm_set_vm_engine_x, scm_c_set_vm_engine_x): New
accessors for VM engines.
(scm_c_set_default_vm_engine_x, scm_set_default_vm_engine_x): New
setters for the default VM engine.
(scm_call_with_vm): New function, applies a procedure to arguments in
a context in which a given VM is current.
* libguile/eval.c (eval, scm_apply): VM dispatch goes through
scm_call_with_vm.
* test-suite/tests/control.test ("the-vm"):
* module/system/vm/coverage.scm (with-code-coverage): Use call-with-vm.
* module/system/vm/vm.scm: Update exports.
* test-suite/vm/run-vm-tests.scm (run-vm-program):
* test-suite/tests/compiler.test ("current-reader"): Just rely on the
result of make-program being an applicable.
* test-suite/tests/eval.test ("stack overflow"): Add a note that this
test does not test what it should.
* libguile/vm.c (vm_dispatch_hook): Take care of FRAME's alignment
explicitly so that it's correct even if the current stack frame isn't
8-byte aligned (as can be the case on i686--the SysV i386 ABI just
says that the stack is word-aligned.)
* libguile/vm-i-system.c (call_cc, tail_call_cc): Call the new
RESTORE_CONTINUATION_HOOK when a continuation is restored.
(prompt): Call the new ABORT_CONTINUATION_HOOK when entering the abort
handler's continuation.
* libguile/vm-engine.h (ABORT_CONTINUATION_HOOK)
(RESTORE_CONTINUATION_HOOK):
* libguile/vm.h (SCM_VM_ABORT_CONTINUATION_HOOK)
(SCM_VM_RESTORE_CONTINUATION_HOOK):
* libguile/vm.c: (scm_vm_abort_continuation_hook): New hook, called when
entering an abort handler.
(scm_vm_restore_continuation_hook): New hook, called after returning
to a continuation.
* module/system/vm/vm.scm: Add hooks to export list.
* libguile/vm.h (SCM_VM_PUSH_CONTINUATION_HOOK)
(SCM_VM_POP_CONTINUATION_HOOK): New hooks, to replace
enter/exit/return.
(SCM_VM_BOOT_HOOK, SCM_VM_HALT_HOOK, SCM_VM_BREAK_HOOK): Remove these
useless hooks.
* libguile/vm.c (scm_vm_push_continuation_hook)
(scm_vm_pop_continuation_hook): New accessors.
* libguile/vm-i-system.c: Remove boot, halt, break, enter, exit, and
return hooks. Also remove the break instruction. Instead now when we
push a new continuation onto the stack we call PUSH_CONTINUATION_HOOK,
and when we pop via a return we call POP_CONTINUATION_HOOK. APPLY_HOOK
is now decoupled from continuation pushes and pops.
* libguile/vm-engine.h:
* libguile/vm-engine.c: Adapt for hooks.
* module/system/vm/trace.scm (vm-trace): Adapt for hooks. Also revive
the #:instructions? #t mode.
* module/system/vm/vm.scm: Adapt exports for new set of hooks.
* libguile/vm-i-scheme.c (ALIGNED_P): New macro.
(BV_FIXABLE_INT_REF, BV_INT_REF, BV_FLOAT_REF, BV_FIXABLE_INT_SET,
BV_INT_SET, BV_FLOAT_SET): Check the alignment of the pointer instead
of checking "i % size == 0". This fixes bus errors on
`sparc64-linux-gnu'.
* libguile/vm.c: Include <alignof.h>.
* libguile/_scm.h (struct scm_aligned_cell)[__GNUC__]: New type.
(union scm_aligned_cell)[!__GNUC__]: New type.
(scm_t_aligned_cell): New type.
* libguile/vm.c (vm_dispatch_hook): Use it.
* libguile/vm-engine.c (VM_NAME)[vm_error_stack_overflow]: Increase
`vp->stack_limit' when possible.
* libguile/vm.c (VM_STACK_RESERVE_SIZE): New macro.
* test-suite/lib.scm (exception:vm-error): New variable.
* test-suite/tests/eval.test ("stack overflow"): New test prefix.
