* doc/ref/compiler.texi (Bytecode): Update macro-assembler instructions,
and move most of them to the instruction set reference.
* doc/ref/vm.texi (A Virtual Machine for Guile, VM Programs): Minor
fixes.
(Instruction Set): Update for Guile 3 instruction set.
* libguile/vm-engine.c (vm_engine): Update a few instruction
docstrings.
* libguile/jit.c (compile_s64_numerically_equal): Remove as this
instruction was removed in previous refactoring.
(compile_atomic_scm_set_immediate), compile_atomic_scm_ref_immediate):
Adapt to change in C name of these instructions.
* libguile/vm-engine.c: Add comments for all instructions.
* libguile/vm-engine.c (abort): If the abort doesn't need to longjmp and
the abort hook was enabled, cache registers first to avoid restoring
a bad IP to the VM.
* libguile/loader.h (SCM_OBJCODE_MINIMUM_MINOR_VERSION):
(SCM_OBJCODE_MINOR_VERSION): Bump version.
* module/system/vm/assembler.scm (*bytecode-minor-version*): Bump.
* libguile/vm-engine.c: Rearrange opcodes to be contiguous and in a
somewhat sensible order.
* libguile/jit.c: Wrap the whole thing in ENABLE_JIT.
* libguile/threads.c (on_thread_exit):
* libguile/vm.c (scm_call_n):
* libguile/init.c (scm_i_init_guile):
* libguile/vm-engine.c (VM_NAME): Wrap calls into jit.c with ENABLE_JIT.
* configure.ac: Move up AC_CANONICAL_TARGET, as autoconf was complaining
about it coming after AC_ARG_PROGRAM.
* acinclude.m4 (GUILE_ENABLE_JIT): Fix to honor --enable-jit arg.
* libguile/vm.c (vm_clear_mcode_return_addresses): New helper.
(vm_recompute_disable_mcode): Force a thread to deoptimize if hooks
become enabled.
(scm_call_n): Don't enter mcode if it's disabled. Also check the right
flag for when to run the abort hook (the abort_hook_enabled flag).
* libguile/vm-engine.c (instrument-entry, instrument-loop)
(return-values, abort, compose-continuation): Don't enter mcode if mcode
is disabled for this thread.
* libguile/vm.h (SCM_VM_NUM_HOOKS): Remove hook enumeration.
(struct scm_vm): Re-arrange members to be more dense and to use common
cache lines for commonly-used members. Declare hooks and their enabled
flags by name.
* libguile/vm-engine.c (RUN_HOOK): Refer to hooks by name.
* libguile/vm.c (FOR_EACH_HOOK): New helper.
(vm_hook_compute_enabled, vm_recompute_disable_mcode): New routines to
recompute when hooks are enabled, and whether to disable mcode because
hooks are active.
(set_vm_trace_level): New helper.
(invoke_hook): Take hook to invoke by value.
(DEFINE_INVOKE_HOOK): Refactor to use named hooks.
(scm_i_vm_prepare_stack): Init named hooks.
(VM_ADD_HOOK, VM_REMOVE_HOOK): Refactor to use named hooks, and also
recompute global disable_mcode flag.
(scm_set_vm_trace_level_x, scm_c_set_vm_engine_x): Use internal helper.
* libguile/intrinsics.h (SCM_FOR_ALL_VM_INTRINSICS): Remove VM hook
intrinsics, now that we're going to rely on the interpreter for
stepping and breakpoints.
* libguile/jit.c (struct scm_jit_state): Remove "hooks_enabled" member,
now that we won't JIT. Remove all code related to calling hooks.
* libguile/vm-engine.c (RUN_HOOK): Call hooks directly instead of
through intrinsics. Use precise per-hook enable flags.
* libguile/vm.c (DEFINE_INVOKE_HOOK): New helper. Use to define the
hook invokers.
* libguile/vm.h (SCM_VM_ABORT_HOOK): Rename from
SCM_VM_ABORT_CONTINUATION_HOOK.
* libguile/vm-engine.c (ABORT_HOOK):
* libguile/vm.c (invoke_abort_hook): Adapt to SCM_VM_ABORT_HOOK name
change.
(reset_vm_hook_enabled): New helper.
(VM_ADD_HOOK, VM_REMOVE_HOOK): New helper macros, replacing
VM_DEFINE_HOOK.
(scm_vm_add_abort_hook_x, scm_vm_remove_abort_hook_x)
(scm_vm_add_apply_hook_x, scm_vm_remove_apply_hook_x)
(scm_vm_add_return_hook_x, scm_vm_remove_return_hook_x)
(scm_vm_add_next_hook_x, scm_vm_remove_next_hook_x): New functions,
replacing direct access to the hooks. Allows us to know in a more
fine-grained way when to enable hooks.
(scm_set_vm_trace_level_x): Use reset_vm_hook_enabled to update the
individual hook_enabled flags.
* module/statprof.scm:
* module/system/vm/coverage.scm:
* module/system/vm/traps.scm:
* module/system/vm/vm.scm: Adapt VM hook users to the new API.
* libguile/vm-engine.c (instrument-entry, instrument-loop): Make the
counter check >=, so that we can set the threshold to 0 and still get
compilation.
* libguile/jit.h (enum scm_jit_counter_value): Make the increments
event.
* libguile/jit.c (scm_jit_counter_threshold): Make a static variable
instead of a compile-time constant.
(scm_init_jit): Init scm_jit_counter_threshold from
GUILE_JIT_COUNTER_THRESHOLD environment variable. Default is -1
indicating "never JIT".
* libguile/vm-engine.c (instrument-entry, instrument-loop): Adapt to new
variable.
* libguile/vm-engine.c (instrument-entry): Eagerly check if data->mcode
is already set, and in that case just jump directly without checking
the counter.
* libguile/intrinsics.h: Add "intrinsic" for handle-interrupts code.
Unlike the other intrinsics, this one isn't a function.
* libguile/programs.c (try_parse_arity): Add cases for instructions used
in VM builtins.
(scm_primitive_call_ip): Return #f if call-ip not found.
* libguile/vm-engine.c (handle-interrupts): Get code from intrinsics.
* libguile/vm.c
* libguile/vm.c (instrumented_code, define_vm_builtins): Add
instrumentation to the builtins, so that they can be JIT-compiled.
(INIT_BUILTIN): Remove min-arity setting; the fallback min-arity
interpreter should figure it out.
(scm_bootstrap_vm): Call the new define_vm_builtins function.
* libguile/gsubr.c (primitive_call_ip): Return 0 if call IP not found.
(primitive_subr_idx): Interpret call ip == 0 as not-a-subr.
* module/system/vm/program.scm (program-arguments-alist): Allow a #f
call-ip.
* libguile/intrinsics.h:
* libguile/intrinsics.c (atomic_ref_scm, atomic_set_scm):
(atomic_swap_scm, atomic_compare_and_swap_scm): New intrinsics, given
that lightning doesn't know atomics.
(scm_bootstrap_intrinsics): Init new intrinsics.
* libguile/vm-engine.c (atomic-scm-ref/immediate)
(atomic-scm-set!/immediate, atomic-scm-swap!/immediate)
(atomic-scm-compare-and-swap!/immediate): Use intrinsics, to be like
the JIT.
* libguile/intrinsics.h (INDIRECT_INT64_INTRINSICS): New definition. If
true, int64 args and return values are passed by reference. Here to
make JIT easier.
* libguile/intrinsics.c (indirect_scm_to_int64, indirect_scm_to_uint64):
(indirect_scm_to_uint64_truncate, indirect_scm_from_int64):
(indirect_scm_from_uint64, indirect_lsh, indirect_rsh): New indirect
variants.
(scm_bootstrap_intrinsics): Use indirect variants as appropriate.
* libguile/vm-engine.c: Update to call indirect intrinsics if
appropriate.
* libguile/intrinsics.h:
* libguile/intrinsics.c (string_set_x): Change to take size_t and u32 as
args.
(allocate_words): Change to take size_t as arg.
* libguile/vm.c (expand_apply_argument): Rename from rest_arg_length,
and also handle the stack manipulation.
* libguile/vm-engine.c (expand-apply-argument): Update for intrinsic
change.
(call-scm-sz-u32): Rename from call-scm-u64-u64, as it matches its
uses and will compile better on 32-bit systems.
* module/system/vm/assembler.scm (define-scm-sz-u32-intrinsic):
(string-set!): Update for new instrinsic call inst.
* libguile/jit.c (compile_call_scm_sz_u32): Adapt.
* libguile/intrinsics.h (SCM_FOR_ALL_VM_INTRINSICS):
* libguile/intrinsics.c (error_wrong_num_args): Take the thread as an
arg, instead of the ostensible callee.
* libguile/vm-engine.c: Update callers of wrong-num-args intrinsic to
pass a thread instead.
* libguile/intrinsics.h (SCM_FOR_ALL_VM_INTRINSICS): Update prototype of
capture-continuation.
* libguile/jit.h:
* libguile/jit.c (scm_jit_enter_mcode): Return void, not the vra.
Instead, we expect the code to set vp->ip for the vra.
* libguile/vm-engine.c (instrument-entry, instrument-loop)
(return-values, abort): Adapt scm_jit_enter_mcode calling convention.
(capture-continuation): No need to pass an mra; the intrinsic will
read it from the stack.
* libguile/vm.c (capture_continuation): Remove mra arg, as we take mra
from the continuation.
(scm_call_n): Adapt to scm_jit_enter_mcode change.
* libguile/continuations.c (scm_i_continuation_to_frame): Adapt to vra
field renaming.
(scm_i_reinstate_continuation, grow_stack, copy_stack_and_call)
(scm_dynthrow): Take mra of continuation. Set on the vp before the
longjmp.
* libguile/continuations.h: Update scm_i_reinstate_continuation
prototype.
* libguile/dynstack.h:
* libguile/control.c (scm_suspendable_continuation_p):
* libguile/dynstack.c (PROMPT_WORDS, PROMPT_VRA, PROMPT_MRA):
(PROMPT_JMPBUF, scm_dynstack_push_prompt, scm_dynstack_find_prompt)
(scm_dynstack_wind_prompt): Store both virtual and machine return
addresses on the dynstack, for prompts.
* libguile/eval.c (eval): Pass NULL for mra.
* libguile/intrinsics.c (push_prompt): Add mra arg, and pass it to the
dynstack.
* libguile/intrinsics.h: Update prototypes so that continuation-related
intrinsics can save and restore the MRA.
* libguile/jit.h:
* libguile/jit.c: Return VRA when JIT code needs to tier down.
* libguile/stacks.c (find_prompt, scm_make_stack)
* libguile/throw.c (catch): Adapt find-prompt calls.
* libguile/vm-engine.c (instrument-entry, instrument-loop): Add logic to
continue with vcode after the mcode finishes.
(compose-continuation, capture-continuation, abort, prompt): Add logic
to pass NULL as captured MRA, but continue with mcode from new
continuations, if appropriate.
* libguile/vm.c (scm_i_vm_cont_to_frame, capture_stack)
(scm_i_capture_current_stack, reinstate_continuation_x)
(capture_continuation, compose_continuation_inner, compose_continuation)
(capture_delimited_continuation, abort_to_prompt): Adapt to plumb
around machine code continuations.
(scm_call_n): Check "mra_after_abort" field for machine code
continuation, if any.
* libguile/vm.h (struct scm_vm): Add "mra_after_abort" field.
(struct scm_vm_cont): Rename "ra" field to "vra" and add "mra" field.
* libguile/foreign.c (scm_i_foreign_call): Rename back from
foreign_call. Need a new trampoline that's easier to call from JIT,
until we actually rewrite the FFI in terms of the JIT.
(scm_register_foreign): Remove foreign_call intrinsic init.
* libguile/intrinsics.h (SCM_FOR_ALL_VM_INTRINSICS): Foreign-call
intrinsic sets return directly on stack.
* libguile/vm-engine.c (foreign-call): Adapt to new intrinsic behavior.
* libguile/vm.c (foreign_call, scm_bootstrap_vm): Add new intrinsic
wrapper.
* libguile/intrinsics.h (SCM_FOR_ALL_VM_INTRINSICS): Make intrinsics for
the VM hooks.
* libguile/vm-engine.c (RUN_HOOK): Run hooks through the intrinsics
table.
* libguile/vm.c (invoke_apply_hook, invoke_return_hook):
(invoke_next_hook, invoke_abort_hook): Rename, remove NOINLINE
attribute (as we call them through the intrinsics table).
(scm_bootstrap_vm): Init new intrinsics.
* libguile/intrinsics.h (SCM_FOR_ALL_VM_INTRINSICS): Add
unpack-values-object.
* libguile/vm-engine.c (subr-call): If the object is a values object,
call out to unpack-values-object. This is to avoid reifying
allocate-frame code in each jitted subr.
* libguile/vm.c (unpack_values_object, scm_bootstrap_vm): Define new
intrinsic.
* libguile/jit.c (compile_capture_continuation): Rename from call_cc now
that the call is elsewhere.
* libguile/vm-engine.c (call, tail-call): Remove needless SYNC_IP before
get-callee-vcode; the intrinsic can sync the ip if needed from the
frame.
(capture-continuation): Rename from call/cc, and leave the call itself
to tail-call.
* libguile/vm.c (vm_builtin_call_with_current_continuation_code): Update
to put the continuation in a local and then tail call.
(get_callee_vcode): Sync vp->ip if we error.
* libguile/intrinsics.h:
* libguile/vm.c (get_callee_vcode): Rename from apply_non_program, and
instead return the IP for the callee of a frame.
(scm_call_n, scm_bootstrap_vm): Adapt to get_callee_vcode change.
* libguile/vm-engine.c (call, tail-call, call/cc): Use
get_callee_vcode unconditionally. JIT will do this to avoid so much
code generation for calls.
Fixes <https://bugs.gnu.org/28211>.
* libguile/vm-engine.c (call, call_label, handle_interrupts): Add
'new_fp' variable; set the dynamic link and return address of the frame
at NEW_FP before setting 'vp->fp'. This fixes a bug whereby, in a
multi-threaded context, the stack-marking code could run after vp->fp
has been set but before its dynamic link has been set, leading the
stack-walking code in 'scm_i_vm_mark_stack' to exit early on.
* libguile/vm-engine.c (RUN_HOOK0, RUN_HOOK1): Remove.
(RUN_HOOK): Take hook name.
(APPLY_HOOK, RETURN_HOOK, NEXT_HOOK, ABORT_CONTINUATION_HOOK): Use
RUN_HOOK.
* libguile/vm.c (vm_dispatch_hook): Remove value count arg; hooks no
longer receive values (e.g. the return hook now uses
frame-return-values).
(vm_dispatch_abort_hook): Remove value count, which was bogus because
the active frame was the continuation which might contain other
locals, potentially unboxed, not the implicit return-values frame. In
the future we could push on an implicit return-values frame instead.
* module/system/vm/traps.scm (trap-in-procedure, trap-frame-finish):
(trap-in-dynamic-extent, trap-calls-to-procedure): Adapt abort hooks
to not take values. They weren't being used anyway!
* libguile/frames.c (scm_frame_return_values): New function, for use
when a frame is at "return-values".
(scm_init_frames_builtins): Register frame-return-values.
* libguile/vm-engine.c (RETURN_HOOK): Rename from POP_CONTINUATION_HOOK.
(call, call-label): Remove PUSH_CONTINUATION_HOOK; it's unneeded, as
you can always check the FP from an apply hook.
(return-values): Run return hook before popping frame.
* libguile/vm.c (vm_dispatch_return_hook): Rename from
vm_dispatch_pop_continuation_hook. Remove push continuation hook.
(scm_vm_return_hook):
* libguile/vm.h (SCM_VM_PUSH_CONTINUATION_HOOK): Remove.
(SCM_VM_RETURN_HOOK): Rename from SCM_VM_POP_CONTINUATION_HOOK.
* module/system/vm/frame.scm (frame-return-values): Export.
* module/system/vm/trace.scm (print-return, trace-calls-to-procedure)
(trace-calls-in-procedure): Adapt to not receiving values as
arguments.
* module/system/vm/traps.scm (trap-in-procedure, trap-frame-finish):
Adapt to return hook coming from returning frame.
(program-sources-by-line): Update to use match instead of pmatch.
* module/system/vm/traps.scm (trap-in-dynamic-extent)
(trap-calls-to-procedure): Adapt to return hook not receiving values.
* module/system/vm/vm.scm: Remove push continuation hook and rename
return hook.
* libguile/gsubr.c: Reimplement to store subr names and procedures in a
side table, and to allocate fresh vcode for each subr. This allows
JIT of subrs, moves to a uniform all-code-starts-with-instrument-entry
regime, and also allows statprof to distinguish between subrs based on
IP.
* libguile/gsubr.h (SCM_SUBRF, SCM_SUBR_NAME): Call out to functions,
now that these are in a side table.
(scm_subr_function, scm_subr_name): New exports.
(scm_i_primitive_name): New internal function, for looking up a
primitive name based on IP.
(scm_apply_subr): Take the subr index.
* libguile/vm-engine.c (subr-call):
* libguile/jit.c (compile_subr_call): Adapt to take index as arg.
* module/statprof.scm (sample-stack-procs, count-call):
(stack-samples->procedure-data): Update to always record IP in stack
samples and call counts.
* module/system/vm/frame.scm (frame-procedure-name): Simplify.
(frame-instruction-pointer-or-primitive-procedure-name): Removed.
* libguile/programs.h:
* libguile/programs.c (scm_primitive_code_name): New function.
* module/system/vm/program.scm (primitive-code-name): New export.
* am/bootstrap.am (SOURCES):
* module/Makefile.am (SOURCES): Handle renamve of handle-interrupts.scm
to loop-instrumentation.scm.
* libguile/jit.h (SCM_JIT_COUNTER_ENTRY_INCREMENT): Rename from
SCM_JIT_COUNTER_CALL_INCREMENT.
* libguile/vm-engine.c (instrument-entry): Rename from instrument-call.
* module/language/cps/compile-bytecode.scm (compile-function): Add
handle-interrupts code before calls and returns. Compile the
"instrument-loop" primcall to an "instrument-loop" instruction and a
"handle-interrupts" instruction.
(lower-cps): Adapt to add-loop-instrumentation name change.
* module/language/cps/loop-instrumentation.scm: Rename from
handle-interrupts.scm and just add "instrument-loop" primcalls in
loops. The compiler will add handle-interrupts primcalls as
appropriate.
* module/system/vm/assembler.scm (<jit-data>): New data type, for
emitting embedded JIT data.
(<meta>): Add field for current JIT data.
(make-meta): Initialize current JIT data.
(emit-instrument-entry*, emit-instrument-loop*): New instruction
emitters that reference the current JIT data.
(end-program): Now that all labels are known, arrange to serialize the
JIT data.
(link-data): Reserve space for JIT data, and add relocs to initialize
the "start" / "end" fields.
* libguile/jit.h (struct scm_jit_function_data)
(enum scm_jit_counter_value): New data types.
* libguile/jit.c (scm_jit_compute_mcode, scm_jit_enter_mcode): New
function stubs. Adapt label/offset compilers to take pointers.
* libguile/vm-engine.c (instrument-call, instrument-loop): New
instructions.
* libguile/vm.c: Add jit.h include.
* module/system/vm/assembler.scm (emit-instrument-call)
(emit-instrument-loop): New exports.
This should reduce frame sizes.
* libguile/vm-engine.c (halt): Adapt to multiple-values change. Also
adapt to not having the boot closure on the stack.
(receive, receive-values, subr-call, foreign-call): Adapt to expect
values one slot down.
(prompt): Capture one less word for the values return.
* libguile/vm.c (vm_dispatch_pop_continuation_hook):
(vm_dispatch_abort_hook): Adapt for where to expect values.
(vm_builtin_values_code): Add a call to shuffle-down before
returning. This is more overhead than what existed before, but the
hope is that the savings elsewhere pay off.
(vm_builtin_values_code): Adapt to different values location.
(reinstate_continuation_x, compose_continuation): Adapt to place
resume args at right position.
(capture_delimited_continuation): Remove unused sp and ip arguments.
(abort_to_prompt): Adapt to capture_delimited_continuation change.
(scm_call_n): Adapt to not reserve space for the boot closure.
* module/language/cps/compile-bytecode.scm (compile-function): When
returning values, adapt reset-frame call for return calling convention
change. Adapt truncating or rest returns to expect values in the
right place.
* module/language/cps/slot-allocation.scm (compute-shuffles):
(allocate-lazy-vars, allocate-slots): Allocate values from the "proc
slot", not proc-slot + 1.
* module/system/vm/assembler.scm (emit-init-constants): Reset the frame
before returning so that the return value is in the right place.
* test-suite/tests/rtl.test: Update for return convention change.
* libguile/foreign.c (get_foreign_stub_code): Update for return calling
convention change.
* libguile/frames.h: Add machine return address to diagram.
(SCM_FRAME_MACHINE_RETURN_ADDRESS):
(SCM_FRAME_SET_MACHINE_RETURN_ADDRESS): New macros.
(SCM_FRAME_PREVIOUS_SP):
(SCM_FRAME_DYNAMIC_LINK):
(SCM_FRAME_SET_DYNAMIC_LINK): Adapt for new frame size.
* libguile/vm-engine.c (halt): Set frame size to 3.
(call, call-label): Set mRA to 0.
* libguile/vm.c (push_interrupt_frame, reinstate_continuation_x):
(scm_call_n): Set frame size to 3. In push_interrupt_frame, init the
mRA of the frame.
(vm_builtin_call_with_values_code, vm_handle_interrupt_code): Allocate
larger frames.
* module/language/cps/slot-allocation.scm (allocate-slots): Frame size
is 3.
* module/system/vm/disassembler.scm (define-clobber-parser): Bump frame
size.
* libguile/frames.c (scm_frame_return_address): Use
SCM_FRAME_VIRTUAL_RETURN_ADDRESS.
(scm_c_frame_previous): Likewise.
* libguile/frames.h: Update diagram for new names.
(union scm_vm_stack_element): Rename "as_ip" to "as_vcode", and
add "as_mcode" for machine code pointers.
(SCM_FRAME_VIRTUAL_RETURN_ADDRESS)
(SCM_FRAME_SET_VIRTUAL_RETURN_ADDRESS): Rename to these, from
SCM_FRAME_RETURN_ADDRESS and SCM_FRAME_SET_RETURN_ADDRESS.
* libguile/vm-engine.c (halt, call, call-label, return-values)
(return-from-interrupt): Adapt to renamings. Make "halt" have frame
size as a parameter.
* libguile/vm.c (scm_i_vm_mark_stack): Adapt to renaming.
(push_interrupt_frame): Take mRA as additional argument. In future we
will set it as frame mRA.
(capture_continuation): Adapt to renaming.
(scm_call_n): Adapt to renaming and make frame size adjustable.
(push_interrupt_frame, reinstate_continuation_x): Make frame size
adjustable.
* module/language/cps/slot-allocation.scm (allocate-slots): Make frame
size adjustable.
* libguile/intrinsics.h (scm_t_thread_mra_intrinsic): New type; use for
push_interrupt_frame.
(scm_t_thread_u8_scm_sp_vra_intrinsic): Rename from the same but was
"ra" instead of "vra", and change type to uint32_t*.
* module/system/vm/disassembler.scm (define-clobber-parser):
Parameterize clobber set for calls by frame size.
* libguile/values.c (scm_c_value_ref): Fix a case in which a request for
the 0th value of a zero-valued object would return the object instead
of erroring.
* libguile/vm-engine.c (halt): Fix construction of a multiple-valued
return (off-by-one error). Fixes a crash introduced in
4a2d78b4d4.
* libguile/instructions.c (DOP1, DOP2, DOP3, DOP4, DOP5): New parts of
the DSL, equivalent to e.g. OP1(x) | OP_DST. Will allow other
definitions of OP* that use token pasting.
* libguile/vm-engine.c: Adapt to use new DOP descriptors.
This reverts commit 593e2db1dd. The goto
strategy works for hooks that run just before a "next"; it doesn't work
for ones that run at the beginning of opcodes.
* libguile/vm-engine.c (GOTO_HOOK, HOOK_HANDLER): Split hooks that don't
take args into a "goto" side and a "target" side. The idea is to just
reify the hook call at one place in the binary, since the VM
continuation is fully in the registers.
(APPLY_HOOK, PUSH_CONTINUATION_HOOK, NEXT_HOOK)
(ABORT_CONTINUATION_HOOK): Reimplement in terms of goto hooks.
(POP_CONTINUATION_HOOK): This one is still old-style.
(CONTINUE): New helper definition.
(call, call-label): Move the push-continuation hooks up a bit, so it's
clear they don't depend on intermediate opcode state.
(vm_engine): Reify hook handlers for apply, etc.
* libguile/vm.c (vm_dispatch_hook): Add a check that we're in the debug
engine and the trace level is positive. Allows us to do cheaper
checks for when to dispatch hooks.
(scm_call_n): Just check if trace level is nonzero.
* libguile/vm-engine.c (RUN_HOOK): Likewise just check if trace level is
nonzero.
* libguile/vm.c (scm_call_n): Only call hooks if the engine supports
it.
(vm_dispatch_abort_hook, vm_dispatch_next_hook)
(vm_dispatch_pop_continuation_hook, vm_dispatch_push_continuation_hook)
(vm_dispatch_apply_hook, vm_dispatch_hook): Take a thread as arg
instead of VM, because that will probably already be in a register in
the VM. Given that all values are taken relative to the SP, no
need to pass that either.
* libguile/vm-engine.c (RUN_HOOK0, RUN_HOOK1): Update appropriately.
* libguile/vm-engine.c (vm_engine): Remove "resume" argument; scm_call_n
will handle the differences.
* libguile/vm.c (scm_call_n): Inline handling of what to do in normal
and resume cases. Remove resume argument to vm_engine.
* libguile/continuations.c (scm_i_make_continuation): Remove registers
argument; instead get from thread.
* libguile/vm-engine.c (vm_engine): Adapt VM engine to not receive a
registers argument, and thus to not pass it to intrinsics either.
* libguile/intrinsics.h:
* libguile/intrinsics.c (push_prompt):
* libguile/vm.c (capture_continuation, compose_continuation)
(abort_to_prompt): Refactor these intrinsics to not take a registers
argument; it's not necessary.
(scm_call_n): Don't pass registers argument.
