From cee1d22c3c10b1892c82a5758ef69cd6fc9aba31 Mon Sep 17 00:00:00 2001 From: Andy Wingo Date: Mon, 22 Feb 2010 23:00:19 +0100 Subject: actually capture partial continuations * libguile/control.c (cont_objcode): Along with a bunch of boilerplate that certainly needs to go in some central place, define this continuation-calling trampoline. (reify_partial_continuation): New function, returns a procedure that when called will reinstate a partial continuation. (scm_c_abort): Take an extra arg, the cookie. Actually reify a continuation. (scm_at_abort): Adapt to scm_c_abort change. * libguile/control.h: Declare scm_c_abort change. * libguile/vm-i-system.c (partial_cont_call): New instruction. (call/cc, tail-call/cc): Adapt to scm_i_vm_capture_stack change. (abort): Pass vm_cookie to abort. * libguile/vm.h (SCM_F_VM_CONT_PARTIAL, SCM_F_VM_CONT_REWINDABLE): New flags. (struct scm_vm_cont): Add flags field. (SCM_VM_CONT_PARTIAL_P, SCM_VM_CONT_REWINDABLE_P): New predicates. * libguile/vm.c (scm_i_vm_capture_stack): Rename from vm_capture_continuation, and make internal instead of static. Take a flags argument. (scm_i_vm_capture_continuation): Adapt to scm_i_vm_capture_stack change. (vm_abort): Plumb cookie to scm_c_abort. (vm_reinstate_partial_continuation): New stub. --- libguile/vm-i-system.c | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-) (limited to 'libguile/vm-i-system.c') diff --git a/libguile/vm-i-system.c b/libguile/vm-i-system.c index faae6ab3e..09293bef8 100644 --- a/libguile/vm-i-system.c +++ b/libguile/vm-i-system.c @@ -993,6 +993,17 @@ VM_DEFINE_INSTRUCTION (89, continuation_call, "continuation-call", 0, -1, 0) abort (); } +VM_DEFINE_INSTRUCTION (94, partial_cont_call, "partial-cont-call", 0, -1, 0) +{ + SCM vmcont, intwinds, extwinds; + POP (extwinds); + POP (intwinds); + POP (vmcont); + + vm_reinstate_partial_continuation (vm, vmcont, intwinds, extwinds); + NEXT; +} + VM_DEFINE_INSTRUCTION (59, tail_call_nargs, "tail-call/nargs", 0, 0, 1) { SCM x; @@ -1099,7 +1110,7 @@ VM_DEFINE_INSTRUCTION (64, call_cc, "call/cc", 0, 1, 1) SCM proc, vm_cont, cont; POP (proc); SYNC_ALL (); - vm_cont = vm_capture_continuation (vp->stack_base, fp, sp, ip, NULL); + vm_cont = scm_i_vm_capture_stack (vp->stack_base, fp, sp, ip, NULL, 0); cont = scm_i_make_continuation (&first, vm, vm_cont); if (first) { @@ -1131,11 +1142,12 @@ VM_DEFINE_INSTRUCTION (65, tail_call_cc, "tail-call/cc", 0, 1, 1) SYNC_ALL (); /* In contrast to call/cc, tail-call/cc captures the continuation without the stack frame. */ - vm_cont = vm_capture_continuation (vp->stack_base, - SCM_FRAME_DYNAMIC_LINK (fp), - SCM_FRAME_LOWER_ADDRESS (fp) - 1, - SCM_FRAME_RETURN_ADDRESS (fp), - SCM_FRAME_MV_RETURN_ADDRESS (fp)); + vm_cont = scm_i_vm_capture_stack (vp->stack_base, + SCM_FRAME_DYNAMIC_LINK (fp), + SCM_FRAME_LOWER_ADDRESS (fp) - 1, + SCM_FRAME_RETURN_ADDRESS (fp), + SCM_FRAME_MV_RETURN_ADDRESS (fp), + 0); cont = scm_i_make_continuation (&first, vm, vm_cont); if (first) { @@ -1511,7 +1523,7 @@ VM_DEFINE_INSTRUCTION (86, abort, "abort", 1, -1, -1) SYNC_REGISTER (); if (sp - n - 2 <= SCM_FRAME_UPPER_ADDRESS (fp)) goto vm_error_stack_underflow; - vm_abort (vm, n); + vm_abort (vm, n, vm_cookie); /* vm_abort should not return */ abort (); } -- cgit v1.2.3