racket/c/prim.c
Matthew Flatt afebbdd6a9 convert GC to "mkgc.ss" implementation
Replace repetitive C code in "gc.c" and "vfasl.c" with an
implementation using a little "Parenthe-C" language, which is a
somewhat declarative description of object tracing. From that
descrition, we generate different kinds of tracing functions, such as
the copy function or the sweep function.

The little language is still bascially C, just with parentheses and
parameterization that is much better than trying to use the C
preprocessor. (The "mkgc.ss" file includes the compiler from
Parenthe-C to C.)

Besides replacing existing code, we also generate a new traversal to
implement `compute-object-sizes`. Finally, the GC can now perform a
fused `collect` and `compute-object-sizes` in a single traversal.

Also improve the way that locked objects are detected during GC. This
can make a significant difference (on the order of 10-20% for a full
collection) when locked objects are long-lived.

original commit: de1f5c41d729ac75822a1f1e633ec6d042c883dc
2020-04-04 10:21:16 -06:00

301 lines
12 KiB
C

/* prim.c
* Copyright 1984-2017 Cisco Systems, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "system.h"
/* locally defined functions */
static void install_library_entry PROTO((ptr n, ptr x));
static void scheme_install_library_entry PROTO((void));
static void create_library_entry_vector PROTO((void));
static void install_c_entry PROTO((iptr i, ptr x));
static void create_c_entry_vector PROTO((void));
static void s_instantiate_code_object PROTO((void));
static void s_link_code_object PROTO((ptr co, ptr objs));
static IBOOL s_check_heap_enabledp PROTO((void));
static void s_enable_check_heap PROTO((IBOOL b));
static uptr s_check_heap_errors PROTO((void));
static void install_library_entry(n, x) ptr n, x; {
if (!Sfixnump(n) || UNFIX(n) < 0 || UNFIX(n) >= library_entry_vector_size)
S_error1("$install-library-entry", "invalid index ~s", n);
if (!Sprocedurep(x) && !Scodep(x))
S_error2("$install-library-entry", "invalid entry ~s for ~s", x, n);
if (Svector_ref(S_G.library_entry_vector, UNFIX(n)) != Sfalse) {
printf("$install-library-entry: overwriting entry for %ld\n", (long)UNFIX(n));
fflush(stdout);
}
SETVECTIT(S_G.library_entry_vector, UNFIX(n), x);
if (n == FIX(library_nonprocedure_code)) {
S_G.nonprocedure_code = x;
S_retrofit_nonprocedure_code();
}
#ifdef X86_64
if (n == FIX(library_cpu_features))
x86_64_set_popcount_present(x);
#endif
}
ptr S_lookup_library_entry(n, errorp) iptr n; IBOOL errorp; {
ptr p;
if (n < 0 || n >= library_entry_vector_size)
S_error1("$lookup-library-entry", "invalid index ~s", FIX(n));
p = Svector_ref(S_G.library_entry_vector, n);
if (p == Sfalse && errorp)
S_error1("$lookup-library-entry", "entry ~s uninitialized", FIX(n));
return p;
}
static void scheme_install_library_entry() {
ptr tc = get_thread_context();
install_library_entry(S_get_scheme_arg(tc, 1), S_get_scheme_arg(tc, 2));
}
static void create_library_entry_vector() {
iptr i;
S_protect(&S_G.library_entry_vector);
S_G.library_entry_vector = S_vector(library_entry_vector_size);
for (i = 0; i < library_entry_vector_size; i++)
INITVECTIT(S_G.library_entry_vector, i) = Sfalse;
}
#ifdef HPUX
#define proc2ptr(x) int2ptr((iptr)(x))
ptr int2ptr(iptr f)
{
if ((f & 2) == 0)
S_error("proc2ptr", "invalid C procedure");
return (ptr)(f & ~0x3);
}
#else /* HPUX */
#define proc2ptr(x) (ptr)(iptr)(x)
#endif /* HPUX */
static void install_c_entry(i, x) iptr i; ptr x; {
if (i < 0 || i >= c_entry_vector_size)
S_error1("install_c_entry", "invalid index ~s", FIX(i));
if (Svector_ref(S_G.c_entry_vector, i) != Sfalse)
S_error1("install_c_entry", "duplicate entry for ~s", FIX(i));
SETVECTIT(S_G.c_entry_vector, i, x);
}
ptr S_lookup_c_entry(i) iptr i; {
ptr x;
if (i < 0 || i >= c_entry_vector_size)
S_error1("lookup_c_entry", "invalid index ~s", FIX(i));
if ((x = Svector_ref(S_G.c_entry_vector, i)) == Sfalse)
S_error1("lookup_c_entry", "uninitialized entry ~s", FIX(i));
return x;
}
static ptr s_get_thread_context() {
return get_thread_context();
}
static void create_c_entry_vector() {
INT i;
S_protect(&S_G.c_entry_vector);
S_G.c_entry_vector = S_vector(c_entry_vector_size);
for (i = 0; i < c_entry_vector_size; i++)
INITVECTIT(S_G.c_entry_vector, i) = Sfalse;
install_c_entry(CENTRY_thread_context, proc2ptr(S_G.thread_context));
install_c_entry(CENTRY_get_thread_context, proc2ptr(s_get_thread_context));
install_c_entry(CENTRY_handle_apply_overflood, proc2ptr(S_handle_apply_overflood));
install_c_entry(CENTRY_handle_docall_error, proc2ptr(S_handle_docall_error));
install_c_entry(CENTRY_handle_overflow, proc2ptr(S_handle_overflow));
install_c_entry(CENTRY_handle_overflood, proc2ptr(S_handle_overflood));
install_c_entry(CENTRY_handle_nonprocedure_symbol, proc2ptr(S_handle_nonprocedure_symbol));
install_c_entry(CENTRY_thread_list, (ptr)&S_threads);
install_c_entry(CENTRY_split_and_resize, proc2ptr(S_split_and_resize));
#ifdef PTHREADS
install_c_entry(CENTRY_raw_collect_cond, (ptr)&S_collect_cond);
install_c_entry(CENTRY_raw_collect_thread0_cond, (ptr)&S_collect_thread0_cond);
install_c_entry(CENTRY_raw_tc_mutex, (ptr)&S_tc_mutex);
install_c_entry(CENTRY_activate_thread, proc2ptr(S_activate_thread));
install_c_entry(CENTRY_deactivate_thread, proc2ptr(Sdeactivate_thread));
install_c_entry(CENTRY_unactivate_thread, proc2ptr(S_unactivate_thread));
#endif /* PTHREADS */
install_c_entry(CENTRY_handle_values_error, proc2ptr(S_handle_values_error));
install_c_entry(CENTRY_handle_mvlet_error, proc2ptr(S_handle_mvlet_error));
install_c_entry(CENTRY_handle_arg_error, proc2ptr(S_handle_arg_error));
install_c_entry(CENTRY_handle_event_detour, proc2ptr(S_handle_event_detour));
install_c_entry(CENTRY_foreign_entry, proc2ptr(S_foreign_entry));
install_c_entry(CENTRY_install_library_entry, proc2ptr(scheme_install_library_entry));
install_c_entry(CENTRY_get_more_room, proc2ptr(S_get_more_room));
install_c_entry(CENTRY_scan_remembered_set, proc2ptr(S_scan_remembered_set));
install_c_entry(CENTRY_instantiate_code_object, proc2ptr(s_instantiate_code_object));
install_c_entry(CENTRY_Sreturn, proc2ptr(S_return));
install_c_entry(CENTRY_Scall_one_result, proc2ptr(S_call_one_result));
install_c_entry(CENTRY_Scall_any_results, proc2ptr(S_call_any_results));
install_c_entry(CENTRY_segment_info, proc2ptr(S_segment_info));
install_c_entry(CENTRY_bignum_mask_test, proc2ptr(S_bignum_mask_test));
for (i = 0; i < c_entry_vector_size; i++) {
#ifndef PTHREADS
if (i == CENTRY_raw_collect_cond || i == CENTRY_raw_tc_mutex
|| i == CENTRY_activate_thread || i == CENTRY_deactivate_thread
|| i == CENTRY_unactivate_thread)
continue;
#endif /* NOT PTHREADS */
if (Svector_ref(S_G.c_entry_vector, i) == Sfalse) {
fprintf(stderr, "c_entry_vector entry %d is uninitialized\n", i);
S_abnormal_exit();
}
}
}
void S_prim_init() {
if (!S_boot_time) return;
create_library_entry_vector();
create_c_entry_vector();
Sforeign_symbol("(cs)fixedpathp", (void *)S_fixedpathp);
Sforeign_symbol("(cs)bytes_allocated", (void *)S_compute_bytes_allocated);
Sforeign_symbol("(cs)curmembytes", (void *)S_curmembytes);
Sforeign_symbol("(cs)maxmembytes", (void *)S_maxmembytes);
Sforeign_symbol("(cs)resetmaxmembytes", (void *)S_resetmaxmembytes);
Sforeign_symbol("(cs)do_gc", (void *)S_do_gc);
Sforeign_symbol("(cs)check_heap_enabledp", (void *)s_check_heap_enabledp);
Sforeign_symbol("(cs)enable_check_heap", (void *)s_enable_check_heap);
Sforeign_symbol("(cs)check_heap_errors", (void *)s_check_heap_errors);
Sforeign_symbol("(cs)count_size_increments", (void *)S_count_size_increments);
Sforeign_symbol("(cs)lookup_library_entry", (void *)S_lookup_library_entry);
Sforeign_symbol("(cs)link_code_object", (void *)s_link_code_object);
Sforeign_symbol("(cs)lookup_c_entry", (void *)S_lookup_c_entry);
Sforeign_symbol("(cs)lock_object", (void *)Slock_object);
Sforeign_symbol("(cs)unlock_object", (void *)Sunlock_object);
Sforeign_symbol("(cs)locked_objectp", (void *)Slocked_objectp);
Sforeign_symbol("(cs)locked_objects", (void *)S_locked_objects);
Sforeign_symbol("(cs)maxgen", (void *)S_maxgen);
Sforeign_symbol("(cs)set_maxgen", (void *)S_set_maxgen);
Sforeign_symbol("(cs)minfreegen", (void *)S_minfreegen);
Sforeign_symbol("(cs)set_minfreegen", (void *)S_set_minfreegen);
Sforeign_symbol("(cs)enable_object_counts", (void *)S_enable_object_counts);
Sforeign_symbol("(cs)set_enable_object_counts", (void *)S_set_enable_object_counts);
Sforeign_symbol("(cs)object_counts", (void *)S_object_counts);
Sforeign_symbol("(cs)unregister_guardian", (void *)S_unregister_guardian);
Sforeign_symbol("(cs)fire_collector", (void *)S_fire_collector);
Sforeign_symbol("(cs)enable_object_backreferences", (void *)S_enable_object_backreferences);
Sforeign_symbol("(cs)set_enable_object_backreferences", (void *)S_set_enable_object_backreferences);
Sforeign_symbol("(cs)object_backreferences", (void *)S_object_backreferences);
}
static void s_instantiate_code_object() {
ptr tc = get_thread_context();
ptr old, cookie, proc;
ptr new, oldreloc, newreloc;
ptr pinfos;
uptr a, m, n;
iptr i, size;
old = S_get_scheme_arg(tc, 1);
cookie = S_get_scheme_arg(tc, 2);
proc = S_get_scheme_arg(tc, 3);
tc_mutex_acquire()
new = S_code(tc, CODETYPE(old), CODELEN(old));
tc_mutex_release()
oldreloc = CODERELOC(old);
size = RELOCSIZE(oldreloc);
newreloc = S_relocation_table(size);
RELOCCODE(newreloc) = new;
for (i = 0; i < size; i += 1) RELOCIT(newreloc, i) = RELOCIT(oldreloc, i);
CODERELOC(new) = newreloc;
CODENAME(new) = CODENAME(old);
CODEARITYMASK(new) = CODEARITYMASK(old);
CODEFREE(new) = CODEFREE(old);
CODEINFO(new) = CODEINFO(old);
CODEPINFOS(new) = pinfos = CODEPINFOS(old);
if (pinfos != Snil) {
S_G.profile_counters = Scons(S_weak_cons(new, pinfos), S_G.profile_counters);
}
for (i = 0; i < CODELEN(old); i++) CODEIT(new,i) = CODEIT(old,i);
m = RELOCSIZE(newreloc);
a = 0;
n = 0;
while (n < m) {
uptr entry, item_off, code_off; ptr obj;
entry = RELOCIT(newreloc, n); n += 1;
if (RELOC_EXTENDED_FORMAT(entry)) {
item_off = RELOCIT(newreloc, n); n += 1;
code_off = RELOCIT(newreloc, n); n += 1;
} else {
item_off = RELOC_ITEM_OFFSET(entry);
code_off = RELOC_CODE_OFFSET(entry);
}
a += code_off;
obj = S_get_code_obj(RELOC_TYPE(entry), old, a, item_off);
/* we've seen the enemy, and he is us */
if (obj == old) obj = new;
/* if we find our cookie, insert proc; otherwise, insert the object
into new to get proper adjustment of relative addresses */
if (obj == cookie)
S_set_code_obj("fcallable", RELOC_TYPE(entry), new, a, proc, item_off);
else
S_set_code_obj("fcallable", RELOC_TYPE(entry), new, a, obj, item_off);
}
S_flush_instruction_cache(tc);
AC0(tc) = new;
}
static void s_link_code_object(co, objs) ptr co, objs; {
ptr t; uptr a, m, n;
t = CODERELOC(co);
m = RELOCSIZE(t);
a = 0;
n = 0;
while (n < m) {
uptr entry, item_off, code_off;
entry = RELOCIT(t, n); n += 1;
if (RELOC_EXTENDED_FORMAT(entry)) {
item_off = RELOCIT(t, n); n += 1;
code_off = RELOCIT(t, n); n += 1;
} else {
item_off = RELOC_ITEM_OFFSET(entry);
code_off = RELOC_CODE_OFFSET(entry);
}
a += code_off;
S_set_code_obj("gc", RELOC_TYPE(entry), co, a, Scar(objs), item_off);
objs = Scdr(objs);
}
}
static INT s_check_heap_enabledp(void) {
return S_checkheap;
}
static void s_enable_check_heap(IBOOL b) {
S_checkheap = b;
}
static uptr s_check_heap_errors(void) {
return S_checkheap_errors;
}