I saw this problem when running elisp.test -- it tries to apply a
function to an arglist ending in nil, which obviously is not null.
* libguile/vm-engine.h (PUSH_LIST): New helper macro, pushes the elements
of a list onto the stack. Checks to make sure that the list is proper.
* libguile/vm-i-system.c (list-break, mv-call, apply, goto/apply)
(goto/cc): Use LIST_BREAK.
* libguile/vm-engine.c (vm_error_improper_list): New error case.
* libguile/vm-i-system.c (goto/cc): Add some asserts here.
* libguile/vm.c (capture_vm_cont): Add some asserts here too.
(reinstate_vm_cont): Null the correct number of bytes. Add a FIXME.
(vm_reset_stack): Make the code a bit clearer. Null the correct number
of bytes.
* libguile/vm-engine.h (NULLSTACK_FOR_NONLOCAL_EXIT): New macro, handles
a very tricky case that took me days to find! Amply commented. Expands
to nothing in the normal case.
* libguile/vm-i-system.c (call, goto/args, mv-call): Call
NULLSTACK_FOR_NONLOCAL_EXIT in the right places. Fixes
continuations.test.
* libguile/vm-engine.h (CHECK_STACK_LEAK, NULLSTACK): Add a new mode,
VM_ENABLE_STACK_NULLING, that tries to ensure that all stack data past
the top of the stack is NULL. This helps to verify the VM's
consistency. If VM_ENABLE_STACK_NULLING is not defined, there is no
overhead.
(DROP, DROPN): Hook into NULLSTACK.
(POP_LIST): Hoo, fix a good bug: if CONS triggered a GC, the elements
of the list that had not yet been consed would not be marked, because
the sp was already below them.
(NEXT): Hook into CHECK_STACK_LEAK.
(INIT_ARGS): Add a note that consing the rest arg can cause GC.
(NEW_FRAME): Cons up the external data after initializing the frame, so
that if GC is triggered, the precise marker sees a well-formed frame.
* libguile/vm-i-loader.c (load-program): In the four-integers case, use
the POP macro so that we can hook into NULLSTACK (if necessary).
* libguile/vm-i-scheme.c (ARGS2, ARGS3): Hook into NULLSTACK.
* libguile/vm-i-system.c (halt): Null the nvalues. Rework some asserts
into using ASSERT, and null the stack when we free the frame.
(variable-set): Use DROPN instead of sp -= 2.
(BR): Hook into NULLSTACK.
(goto/args): Hook into NULLSTACK. In the non-self case, delay updating
the frame until after INIT_ARGS so that GC sees a well-formed frame.
Delay consing the externals until after the frame is set up, as in
NEW_FRAME.
(call/cc): Add some asserts.
(return): Rework some asserts into ASSERT, and hook into NULLSTACK.
(return/values): Hook into NULLSTACK, and use ASSERT.
(return/values*) Use ASSERT.
* libguile/vm.c (VM_ENABLE_ASSERTIONS, VM_ENABLE_STACK_NULLING): These
are the variables that control assertions and nulling. Perhaps we can
do these per-engine when we start compiling the debug engine separate
from a speedy engine.
(vm_mark_stack): Add a precise stack marker. Yay!
(vm_cont_mark): Mark the continuation stack precisely.
(capture_vm_cont): Record the difference from the vp's stack_base too,
so that we can translate the dynamic links when marking the
continuation stack. Memset the stack to NULL if we are doing nulling.
(reinstate_vm_cont): If we are nulling, null out the relevant part
of the stack.
(vm_reset_stack): When resetting sp due to a nonlocal exit, null out
the stack too.
(vm_mark): If we are nulling, assert that there are no extra values on
the stack. Mark the stack precisely.
* libguile/vm-engine.c: Call scm_wrong_num_args in the wrong-num-args
case, to be more like the interpreter.
* libguile/vm-engine.h (ASSERT): New macro.
* libguile/vm-i-system.c (apply, goto/apply): Assert that nargs >= 2,
because the compiler should always feed us correct instructions.
(call/cc): If no values are returned to the continuation, signal
no_values instead of wrong_num_args.
* libguile/vm-engine.h (POP_CONS_MARK): New macro, analagous to
POP_LIST_MARK; used in quasiquote on improper lists.
* libguile/vm-i-system.c (cons-mark): New instruction. You know the
drill, remove all your .go files please.
* module/system/il/compile.scm (codegen): Compile quasiquoted improper
lists with splices correctly. Additionally check that we don't have
slices in the CDR of an improper list.
* testsuite/t-quasiquote.scm: Add a test for unquote-splicing in improper
lists.
* libguile/frames.c (frame-mv-return-address): New accessor.
* libguile/frames.h: Update frame diagram.
(SCM_FRAME_UPPER_ADDRESS): Update for data area
growing by one pointer.
(SCM_FRAME_MV_RETURN_ADDRESS): New macro.
* libguile/vm-engine.h (NEW_FRAME): Update for frame getting bigger by a
pointer. In a normal NEW_FRAME, set the MV return address to NULL, to
indicate that this continuation does not accept multiple values.
* libguile/vm-i-system.c (tail-call): Update frame replacement code to
understand the MV return address.
(return): Make room for the MVRA.
* libguile/programs.c (program_print): Only try to lookup write-program
if the module system is booted.
* libguile/vm-engine.h (FREE_FRAME): Remove, it's now inlined everywhere.
* libguile/vm-i-system.c (tail-call): Inline FREE_FRAME, and implement
the calling bits here. Will make things more hackable.
* ice-9/boot-9.scm: Only define load-compiled as #f if it's not already
defined, which won't normally be the case.
* libguile/guile-vm.c: Removed, there's no more guile-vm binary.
* libguile/frames.c: (with change frame? -> heap-frame?)
* libguile/frames.h:
* libguile/instructions.c:
* libguile/instructions.h:
* libguile/objcodes.c:
* libguile/objcodes.h:
* libguile/programs.c:
* libguile/programs.h:
* libguile/vm-bootstrap.h: (was bootstrap.h)
* libguile/vm-engine.c: (was vm_engine.c)
* libguile/vm-engine.h: (was vm_engine.h)
* libguile/vm-expand.h: (was vm_expand.h)
* libguile/vm-i-loader.c: (was vm_loader.c)
* libguile/vm-i-scheme.c: (was vm_scheme.c)
* libguile/vm-i-system.c: (was vm_system.c)
* libguile/vm.c:
* libguile/vm.h: These files moved here from src/, as guile-vm is now a
part of libguile.
* libguile/init.c: Bootstrap the VM. Yay!
* libguile/Makefile.am: The necessary chicanery here.
* module/system/vm/Makefile.am:
* module/system/vm/bootstrap.scm:
* module/system/vm/frame.scm:
* module/system/vm/instruction.scm:
* module/system/vm/objcode.scm:
* module/system/vm/program.scm:
* module/system/vm/vm.scm:
* pre-inst-guile-env.in: Add builddirs to the load path; add module/ to
the path in the empty-$GUILE_LOAD_PATH case as well.
* src/Makefile.am: Moved out everything except guilec and guile-disasm,
which probably should be moved to the scripts directory?
* testsuite/Makefile.am: Update to find guile-vm in the right place.
* module/system/vm/Makefile.am:
* module/system/vm/bootstrap.scm: Removed bootstrap.scm, scm_init_guile
handles the bootstrapping for us.
* module/system/vm/frame.scm:
* module/system/vm/instruction.scm:
* module/system/vm/objcode.scm:
* module/system/vm/program.scm:
* module/system/vm/vm.scm: Call the init functions in libguile; should
fix at some point to avoid the dlopen?
