diff options
author | Andy Wingo <wingo@pobox.com> | 2011-03-15 23:33:32 +0100 |
---|---|---|
committer | Andy Wingo <wingo@pobox.com> | 2011-03-15 23:45:58 +0100 |
commit | 9b709b0fe1ec5a71903e07d21006441d15e0c1ed (patch) | |
tree | 21ba9462ce57a01a57e5c7ab9a2d167a5fd299ef | |
parent | 958173e489c69b2f9e3c83752713a89e3ea3e79d (diff) | |
download | guile-9b709b0fe1ec5a71903e07d21006441d15e0c1ed.tar.gz |
fix frame dynamic linkage in the face of partial continuation application
* libguile/vm-i-system.c (new-frame): Though it was appealing to set the
dynamic link here on the incomplete frame, we no longer do that, for
the reasons mentioned in the code.
(call, mv-call): Adapt to set the frame's dynamic link.
* libguile/vm-engine.c (vm_engine): Don't set dynamic link here, even
for boot program.
* libguile/frames.c (scm_frame_num_locals, scm_frame_local_ref)
(scm_frame_local_set_x): Fix up not-yet-active frame detection.
-rw-r--r-- | libguile/frames.c | 6 | ||||
-rw-r--r-- | libguile/vm-engine.c | 2 | ||||
-rw-r--r-- | libguile/vm-i-system.c | 49 |
3 files changed, 40 insertions, 17 deletions
diff --git a/libguile/frames.c b/libguile/frames.c index bc1bb82a8..62ba23fff 100644 --- a/libguile/frames.c +++ b/libguile/frames.c @@ -124,7 +124,7 @@ SCM_DEFINE (scm_frame_num_locals, "frame-num-locals", 1, 0, 0, p = SCM_FRAME_STACK_ADDRESS (SCM_VM_FRAME_FP (frame)); while (p <= sp) { - if (p + 1 < sp && p[1] == (SCM)0) + if (p[0] == (SCM)0) /* skip over not-yet-active frame */ p += 3; else @@ -154,7 +154,7 @@ SCM_DEFINE (scm_frame_local_ref, "frame-local-ref", 2, 0, 0, p = SCM_FRAME_STACK_ADDRESS (SCM_VM_FRAME_FP (frame)); while (p <= sp) { - if (p + 1 < sp && p[1] == (SCM)0) + if (p[0] == (SCM)0) /* skip over not-yet-active frame */ p += 3; else if (n == i) @@ -186,7 +186,7 @@ SCM_DEFINE (scm_frame_local_set_x, "frame-local-set!", 3, 0, 0, p = SCM_FRAME_STACK_ADDRESS (SCM_VM_FRAME_FP (frame)); while (p <= sp) { - if (p + 1 < sp && p[1] == (SCM)0) + if (p[0] == (SCM)0) /* skip over not-yet-active frame */ p += 3; else if (n == i) diff --git a/libguile/vm-engine.c b/libguile/vm-engine.c index 20d9ed2c8..4b0ca3ec3 100644 --- a/libguile/vm-engine.c +++ b/libguile/vm-engine.c @@ -93,7 +93,7 @@ VM_NAME (SCM vm, SCM program, SCM *argv, int nargs) fp = sp + 1; ip = SCM_C_OBJCODE_BASE (bp); /* MV-call frame, function & arguments */ - PUSH ((SCM)fp); /* dynamic link */ + PUSH (0); /* dynamic link */ PUSH (0); /* mvra */ PUSH (0); /* ra */ PUSH (prog); diff --git a/libguile/vm-i-system.c b/libguile/vm-i-system.c index 57712cabd..980d22afe 100644 --- a/libguile/vm-i-system.c +++ b/libguile/vm-i-system.c @@ -756,9 +756,14 @@ VM_DEFINE_INSTRUCTION (52, new_frame, "new-frame", 0, 0, 3) { /* NB: if you change this, see frames.c:vm-frame-num-locals */ /* and frames.h, vm-engine.c, etc of course */ - PUSH ((SCM)fp); /* dynamic link */ - PUSH (0); /* mvra */ - PUSH (0); /* ra */ + + /* We don't initialize the dynamic link here because we don't actually + know that this frame will point to the current fp: it could be + placed elsewhere on the stack if captured in a partial + continuation, and invoked from some other context. */ + PUSH (0); /* dynamic link */ + PUSH (0); /* mvra */ + PUSH (0); /* ra */ NEXT; } @@ -790,11 +795,20 @@ VM_DEFINE_INSTRUCTION (53, call, "call", 1, -1, 1) } CACHE_PROGRAM (); - fp = sp - nargs + 1; - ASSERT (SCM_FRAME_RETURN_ADDRESS (fp) == 0); - ASSERT (SCM_FRAME_MV_RETURN_ADDRESS (fp) == 0); - SCM_FRAME_SET_RETURN_ADDRESS (fp, ip); - SCM_FRAME_SET_MV_RETURN_ADDRESS (fp, 0); + + { + SCM *old_fp = fp; + + fp = sp - nargs + 1; + + ASSERT (SCM_FRAME_DYNAMIC_LINK (fp) == 0); + ASSERT (SCM_FRAME_RETURN_ADDRESS (fp) == 0); + ASSERT (SCM_FRAME_MV_RETURN_ADDRESS (fp) == 0); + SCM_FRAME_SET_DYNAMIC_LINK (fp, old_fp); + SCM_FRAME_SET_RETURN_ADDRESS (fp, ip); + SCM_FRAME_SET_MV_RETURN_ADDRESS (fp, 0); + } + ip = SCM_C_OBJCODE_BASE (bp); PUSH_CONTINUATION_HOOK (); APPLY_HOOK (); @@ -1091,11 +1105,20 @@ VM_DEFINE_INSTRUCTION (62, mv_call, "mv-call", 4, -1, 1) } CACHE_PROGRAM (); - fp = sp - nargs + 1; - ASSERT (SCM_FRAME_RETURN_ADDRESS (fp) == 0); - ASSERT (SCM_FRAME_MV_RETURN_ADDRESS (fp) == 0); - SCM_FRAME_SET_RETURN_ADDRESS (fp, ip); - SCM_FRAME_SET_MV_RETURN_ADDRESS (fp, mvra); + + { + SCM *old_fp = fp; + + fp = sp - nargs + 1; + + ASSERT (SCM_FRAME_DYNAMIC_LINK (fp) == 0); + ASSERT (SCM_FRAME_RETURN_ADDRESS (fp) == 0); + ASSERT (SCM_FRAME_MV_RETURN_ADDRESS (fp) == 0); + SCM_FRAME_SET_DYNAMIC_LINK (fp, old_fp); + SCM_FRAME_SET_RETURN_ADDRESS (fp, ip); + SCM_FRAME_SET_MV_RETURN_ADDRESS (fp, mvra); + } + ip = SCM_C_OBJCODE_BASE (bp); PUSH_CONTINUATION_HOOK (); APPLY_HOOK (); |