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-rw-r--r--libguile/continuations.c209
1 files changed, 59 insertions, 150 deletions
diff --git a/libguile/continuations.c b/libguile/continuations.c
index d9912783d..1d677610b 100644
--- a/libguile/continuations.c
+++ b/libguile/continuations.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1995,1996,1998,2000,2001,2004, 2006, 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc.
+/* Copyright (C) 1995,1996,1998,2000,2001,2004, 2006, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
@@ -24,6 +24,7 @@
#include "libguile/_scm.h"
+#include <assert.h>
#include <string.h>
#include <stdio.h>
@@ -33,7 +34,7 @@
#include "libguile/stackchk.h"
#include "libguile/smob.h"
#include "libguile/ports.h"
-#include "libguile/dynwind.h"
+#include "libguile/dynstack.h"
#include "libguile/eval.h"
#include "libguile/vm.h"
#include "libguile/instructions.h"
@@ -52,113 +53,31 @@ static scm_t_bits tc16_continuation;
#define SCM_SET_CONTINUATION_LENGTH(x, n)\
(SCM_CONTREGS (x)->num_stack_items = (n))
#define SCM_JMPBUF(x) ((SCM_CONTREGS (x))->jmpbuf)
-#define SCM_DYNENV(x) ((SCM_CONTREGS (x))->dynenv)
#define SCM_CONTINUATION_ROOT(x) ((SCM_CONTREGS (x))->root)
#define SCM_DFRAME(x) ((SCM_CONTREGS (x))->dframe)
-/* scm_i_make_continuation will return a procedure whose objcode contains an
- instruction to reinstate the continuation. Here, as in gsubr.c and smob.c, we
- define the form of that trampoline function.
+/* scm_i_make_continuation will return a procedure whose code will
+ reinstate the continuation. Here, as in gsubr.c, we define the form
+ of that trampoline function.
*/
-#ifdef WORDS_BIGENDIAN
-#define OBJCODE_HEADER(main,meta) 0, 0, 0, main, 0, 0, 0, meta+8
-#define META_HEADER(meta) 0, 0, 0, meta, 0, 0, 0, 0
-#else
-#define OBJCODE_HEADER(main,meta) main, 0, 0, 0, meta+8, 0, 0, 0
-#define META_HEADER(meta) meta, 0, 0, 0, 0, 0, 0, 0
-#endif
-
-#define OBJCODE_TAG SCM_MAKE_OBJCODE_TAG (SCM_OBJCODE_TYPE_STATIC, 0)
-
-#if defined (SCM_ALIGNED) && 0
-#define SCM_DECLARE_STATIC_ALIGNED_ARRAY(type, sym) \
-static const type sym[]
-#define SCM_STATIC_ALIGNED_ARRAY(alignment, type, sym) \
-static SCM_ALIGNED (alignment) const type sym[]
-#define SCM_STATIC_OBJCODE(sym) \
- SCM_DECLARE_STATIC_ALIGNED_ARRAY (scm_t_uint8, sym##__bytecode); \
- SCM_STATIC_ALIGNED_ARRAY (8, scm_t_cell, sym##__cells) = { \
- { SCM_PACK (OBJCODE_TAG), SCM_PACK (sym##__bytecode) }, \
- { SCM_BOOL_F, SCM_PACK (0) } \
- }; \
- static const SCM sym = SCM_PACK (sym##__cells); \
- SCM_STATIC_ALIGNED_ARRAY (8, scm_t_uint8, sym##__bytecode)
-#else
-#define SCM_STATIC_OBJCODE(sym) \
-static SCM sym; \
-static scm_t_uint8 *sym##_bytecode; \
-SCM_SNARF_INIT(sym##_bytecode = scm_gc_malloc_pointerless (sizeof(sym##_bytecode__unaligned), "partial continuation stub"); \
- memcpy (sym##_bytecode, sym##_bytecode__unaligned, sizeof(sym##_bytecode__unaligned));) \
-SCM_SNARF_INIT(sym = scm_double_cell (OBJCODE_TAG, \
- (scm_t_bits)sym##_bytecode, \
- SCM_UNPACK (SCM_BOOL_F), \
- 0);) \
-static const scm_t_uint8 sym##_bytecode__unaligned[]
-#endif
-
-
-SCM_STATIC_OBJCODE (cont_objcode) = {
- /* This code is the same as in gsubr.c, except we use continuation_call
- instead of subr_call. */
- OBJCODE_HEADER (8, 19),
- /* leave args on the stack */
- /* 0 */ scm_op_object_ref, 0, /* push scm_t_contregs smob */
- /* 2 */ scm_op_continuation_call, /* and longjmp (whee) */
- /* 3 */ scm_op_nop, /* pad to 8 bytes */
- /* 4 */ scm_op_nop, scm_op_nop, scm_op_nop, scm_op_nop,
- /* 8 */
-
- /* We could put some meta-info to say that this proc is a continuation. Not sure
- how to do that, though. */
- META_HEADER (19),
- /* 0 */ scm_op_make_eol, /* bindings */
- /* 1 */ scm_op_make_eol, /* sources */
- /* 2 */ scm_op_make_int8, 0, scm_op_make_int8, 3, /* arity: from ip 0 to ip 3 */
- /* 6 */ scm_op_make_int8_0, /* the arity is 0 required args */
- /* 7 */ scm_op_make_int8_0, /* 0 optionals */
- /* 8 */ scm_op_make_true, /* and a rest arg */
- /* 9 */ scm_op_list, 0, 5, /* make a list of those 5 vals */
- /* 12 */ scm_op_list, 0, 1, /* and the arities will be a list of that one list */
- /* 15 */ scm_op_list, 0, 3, /* pack bindings, sources, and arities into list */
- /* 18 */ scm_op_return /* and return */
- /* 19 */
-};
-
-
-SCM_STATIC_OBJCODE (call_cc_objcode) = {
- /* Before Scheme's call/cc is compiled, eval.c will use this hand-coded
- call/cc. */
- OBJCODE_HEADER (8, 17),
- /* 0 */ scm_op_assert_nargs_ee, 0, 1, /* assert that nargs==1 */
- /* 3 */ scm_op_local_ref, 0, /* push the proc */
- /* 5 */ scm_op_tail_call_cc, /* and call/cc */
- /* 6 */ scm_op_nop, scm_op_nop, /* pad to 8 bytes */
- /* 8 */
-
- META_HEADER (17),
- /* 0 */ scm_op_make_eol, /* bindings */
- /* 1 */ scm_op_make_eol, /* sources */
- /* 2 */ scm_op_make_int8, 3, scm_op_make_int8, 6, /* arity: from ip 0 to ip 6 */
- /* 6 */ scm_op_make_int8_1, /* the arity is 0 required args */
- /* 7 */ scm_op_list, 0, 3, /* make a list of those 5 vals */
- /* 10 */ scm_op_list, 0, 1, /* and the arities will be a list of that one list */
- /* 13 */ scm_op_list, 0, 3, /* pack bindings, sources, and arities into list */
- /* 16 */ scm_op_return /* and return */
- /* 17 */
-};
-
+static const scm_t_uint32 continuation_stub_code[] =
+ {
+ SCM_PACK_OP_24 (continuation_call, 0)
+ };
static SCM
make_continuation_trampoline (SCM contregs)
{
- SCM ret = scm_make_program (cont_objcode,
- scm_c_make_vector (1, contregs),
- SCM_BOOL_F);
- SCM_SET_CELL_WORD_0 (ret,
- SCM_CELL_WORD_0 (ret) | SCM_F_PROGRAM_IS_CONTINUATION);
+ SCM ret;
+ scm_t_bits nfree = 1;
+ scm_t_bits flags = SCM_F_PROGRAM_IS_CONTINUATION;
+
+ ret = scm_words (scm_tc7_program | (nfree << 16) | flags, nfree + 2);
+ SCM_SET_CELL_WORD_1 (ret, continuation_stub_code);
+ SCM_PROGRAM_FREE_VARIABLE_SET (ret, 0, contregs);
return ret;
}
@@ -173,20 +92,31 @@ continuation_print (SCM obj, SCM port, scm_print_state *state SCM_UNUSED)
{
scm_t_contregs *continuation = SCM_CONTREGS (obj);
- scm_puts ("#<continuation ", port);
+ scm_puts_unlocked ("#<continuation ", port);
scm_intprint (continuation->num_stack_items, 10, port);
- scm_puts (" @ ", port);
+ scm_puts_unlocked (" @ ", port);
scm_uintprint (SCM_SMOB_DATA_1 (obj), 16, port);
- scm_putc ('>', port);
+ scm_putc_unlocked ('>', port);
return 1;
}
+/* James Clark came up with this neat one instruction fix for
+ * continuations on the SPARC. It flushes the register windows so
+ * that all the state of the process is contained in the stack.
+ */
+
+#if defined (sparc) || defined (__sparc__) || defined (__sparc)
+# define SCM_FLUSH_REGISTER_WINDOWS asm("ta 3")
+#else
+# define SCM_FLUSH_REGISTER_WINDOWS /* empty */
+#endif
+
/* this may return more than once: the first time with the escape
procedure, then subsequently with SCM_UNDEFINED (the vals already having been
placed on the VM stack). */
#define FUNC_NAME "scm_i_make_continuation"
SCM
-scm_i_make_continuation (int *first, SCM vm, SCM vm_cont)
+scm_i_make_continuation (int *first, struct scm_vm *vp, SCM vm_cont)
{
scm_i_thread *thread = SCM_I_CURRENT_THREAD;
SCM cont;
@@ -200,7 +130,6 @@ scm_i_make_continuation (int *first, SCM vm, SCM vm_cont)
+ (stack_size - 1) * sizeof (SCM_STACKITEM),
"continuation");
continuation->num_stack_items = stack_size;
- continuation->dynenv = scm_i_dynwinds ();
continuation->root = thread->continuation_root;
src = thread->continuation_base;
#if ! SCM_STACK_GROWS_UP
@@ -208,7 +137,7 @@ scm_i_make_continuation (int *first, SCM vm, SCM vm_cont)
#endif
continuation->offset = continuation->stack - src;
memcpy (continuation->stack, src, sizeof (SCM_STACKITEM) * stack_size);
- continuation->vm = vm;
+ continuation->vp = vp;
continuation->vm_cont = vm_cont;
SCM_NEWSMOB (cont, tc16_continuation, continuation);
@@ -237,42 +166,30 @@ scm_i_make_continuation (int *first, SCM vm, SCM vm_cont)
#undef FUNC_NAME
SCM
-scm_i_call_with_current_continuation (SCM proc)
-{
- static SCM call_cc = SCM_BOOL_F;
-
- if (scm_is_false (call_cc))
- call_cc = scm_make_program (call_cc_objcode, SCM_BOOL_F, SCM_BOOL_F);
-
- return scm_call_1 (call_cc, proc);
-}
-
-SCM
scm_i_continuation_to_frame (SCM continuation)
{
SCM contregs;
scm_t_contregs *cont;
- contregs = scm_c_vector_ref (scm_program_objects (continuation), 0);
+ contregs = SCM_PROGRAM_FREE_VARIABLE_REF (continuation, 0);
cont = SCM_CONTREGS (contregs);
if (scm_is_true (cont->vm_cont))
{
struct scm_vm_cont *data = SCM_VM_CONT_DATA (cont->vm_cont);
- return scm_c_make_frame (cont->vm_cont,
- data->fp + data->reloc,
- data->sp + data->reloc,
- data->ra,
- data->reloc);
+ return scm_c_make_frame (SCM_VM_FRAME_KIND_CONT, data,
+ (data->fp + data->reloc) - data->stack_base,
+ (data->sp + data->reloc) - data->stack_base,
+ data->ra);
}
else
return SCM_BOOL_F;
}
-SCM
-scm_i_contregs_vm (SCM contregs)
+struct scm_vm *
+scm_i_contregs_vp (SCM contregs)
{
- return SCM_CONTREGS (contregs)->vm;
+ return SCM_CONTREGS (contregs)->vp;
}
SCM
@@ -323,33 +240,25 @@ grow_stack (SCM cont)
* own frame are overwritten. Thus, memcpy can be used for best performance.
*/
-typedef struct {
- scm_t_contregs *continuation;
- SCM_STACKITEM *dst;
-} copy_stack_data;
-
-static void
-copy_stack (void *data)
-{
- copy_stack_data *d = (copy_stack_data *)data;
- memcpy (d->dst, d->continuation->stack,
- sizeof (SCM_STACKITEM) * d->continuation->num_stack_items);
-#ifdef __ia64__
- SCM_I_CURRENT_THREAD->pending_rbs_continuation = d->continuation;
-#endif
-}
-
static void
copy_stack_and_call (scm_t_contregs *continuation,
SCM_STACKITEM * dst)
{
- long delta;
- copy_stack_data data;
+ scm_t_dynstack *dynstack;
+ scm_t_bits *joint;
+ scm_i_thread *thread = SCM_I_CURRENT_THREAD;
+
+ dynstack = SCM_VM_CONT_DATA (continuation->vm_cont)->dynstack;
+
+ joint = scm_dynstack_unwind_fork (&thread->dynstack, dynstack);
+
+ memcpy (dst, continuation->stack,
+ sizeof (SCM_STACKITEM) * continuation->num_stack_items);
+#ifdef __ia64__
+ thread->pending_rbs_continuation = continuation;
+#endif
- delta = scm_ilength (scm_i_dynwinds ()) - scm_ilength (continuation->dynenv);
- data.continuation = continuation;
- data.dst = dst;
- scm_i_dowinds (continuation->dynenv, delta, copy_stack, &data);
+ scm_dynstack_wind (&thread->dynstack, joint);
SCM_I_LONGJMP (continuation->jmpbuf, 1);
}
@@ -486,7 +395,7 @@ print_exception_and_backtrace (SCM port, SCM tag, SCM args)
if (should_print_backtrace (tag, stack))
{
- scm_puts ("Backtrace:\n", port);
+ scm_puts_unlocked ("Backtrace:\n", port);
scm_display_backtrace_with_highlights (stack, port,
SCM_BOOL_F, SCM_BOOL_F,
SCM_EOL);
@@ -531,7 +440,7 @@ pre_unwind_handler (void *error_port, SCM tag, SCM args)
{
/* Print the exception unless TAG is `quit'. */
if (!scm_is_eq (tag, scm_from_latin1_symbol ("quit")))
- print_exception_and_backtrace (PTR2SCM (error_port), tag, args);
+ print_exception_and_backtrace (SCM_PACK_POINTER (error_port), tag, args);
return SCM_UNSPECIFIED;
}
@@ -545,7 +454,7 @@ scm_c_with_continuation_barrier (void *(*func) (void *), void *data)
scm_i_with_continuation_barrier (c_body, &c_data,
c_handler, &c_data,
pre_unwind_handler,
- SCM2PTR (scm_current_error_port ()));
+ SCM_UNPACK_POINTER (scm_current_error_port ()));
return c_data.result;
}
@@ -589,7 +498,7 @@ SCM_DEFINE (scm_with_continuation_barrier, "with-continuation-barrier", 1,0,0,
return scm_i_with_continuation_barrier (scm_body, &scm_data,
scm_handler, &scm_data,
pre_unwind_handler,
- SCM2PTR (scm_current_error_port ()));
+ SCM_UNPACK_POINTER (scm_current_error_port ()));
}
#undef FUNC_NAME