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vm: Record exception ip only for instructions where exceptions may happen.

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Mirroring ip to a volatile memory variable for each opcode is an expensive
operation. For quite a lot of often executed opcodes like stack manipulation
or jumps, exceptions cannot actually happen. So, record ip only for opcode
where that's possible.
This commit is contained in:
Paul Sokolovsky 2014-12-28 07:17:43 +02:00
parent 1570eaf0e3
commit 749575097f
1 changed files with 58 additions and 2 deletions
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60
py/vm.c
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@ -101,11 +101,19 @@ typedef enum {
// MP_VM_RETURN_YIELD, ip, sp valid, yielded value in *sp // MP_VM_RETURN_YIELD, ip, sp valid, yielded value in *sp
// MP_VM_RETURN_EXCEPTION, exception in fastn[0] // MP_VM_RETURN_EXCEPTION, exception in fastn[0]
mp_vm_return_kind_t mp_execute_bytecode(mp_code_state *code_state, volatile mp_obj_t inject_exc) { mp_vm_return_kind_t mp_execute_bytecode(mp_code_state *code_state, volatile mp_obj_t inject_exc) {
#define SELECTIVE_EXC_IP (0)
#if SELECTIVE_EXC_IP
#define MARK_EXC_IP_SELECTIVE() { code_state->ip = ip - 1; }
#define MARK_EXC_IP_GLOBAL()
#else
#define MARK_EXC_IP_SELECTIVE()
#define MARK_EXC_IP_GLOBAL() { code_state->ip = ip; }
#endif
#if MICROPY_OPT_COMPUTED_GOTO #if MICROPY_OPT_COMPUTED_GOTO
#include "vmentrytable.h" #include "vmentrytable.h"
#define DISPATCH() do { \ #define DISPATCH() do { \
TRACE(ip); \ TRACE(ip); \
code_state->ip = ip; \ MARK_EXC_IP_GLOBAL(); \
goto *entry_table[*ip++]; \ goto *entry_table[*ip++]; \
} while(0) } while(0)
#define DISPATCH_WITH_PEND_EXC_CHECK() goto pending_exception_check #define DISPATCH_WITH_PEND_EXC_CHECK() goto pending_exception_check
@ -161,7 +169,7 @@ dispatch_loop:
DISPATCH(); DISPATCH();
#else #else
TRACE(ip); TRACE(ip);
code_state->ip = ip; MARK_EXC_IP_GLOBAL();
switch (*ip++) { switch (*ip++) {
#endif #endif
@ -201,6 +209,7 @@ dispatch_loop:
} }
ENTRY(MP_BC_LOAD_CONST_DEC): { ENTRY(MP_BC_LOAD_CONST_DEC): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
PUSH(mp_load_const_dec(qst)); PUSH(mp_load_const_dec(qst));
DISPATCH(); DISPATCH();
@ -228,6 +237,7 @@ dispatch_loop:
load_check: load_check:
if (obj_shared == MP_OBJ_NULL) { if (obj_shared == MP_OBJ_NULL) {
local_name_error: { local_name_error: {
MARK_EXC_IP_SELECTIVE();
mp_obj_t obj = mp_obj_new_exception_msg(&mp_type_NameError, "local variable referenced before assignment"); mp_obj_t obj = mp_obj_new_exception_msg(&mp_type_NameError, "local variable referenced before assignment");
RAISE(obj); RAISE(obj);
} }
@ -243,24 +253,28 @@ dispatch_loop:
} }
ENTRY(MP_BC_LOAD_NAME): { ENTRY(MP_BC_LOAD_NAME): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
PUSH(mp_load_name(qst)); PUSH(mp_load_name(qst));
DISPATCH(); DISPATCH();
} }
ENTRY(MP_BC_LOAD_GLOBAL): { ENTRY(MP_BC_LOAD_GLOBAL): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
PUSH(mp_load_global(qst)); PUSH(mp_load_global(qst));
DISPATCH(); DISPATCH();
} }
ENTRY(MP_BC_LOAD_ATTR): { ENTRY(MP_BC_LOAD_ATTR): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
SET_TOP(mp_load_attr(TOP(), qst)); SET_TOP(mp_load_attr(TOP(), qst));
DISPATCH(); DISPATCH();
} }
ENTRY(MP_BC_LOAD_METHOD): { ENTRY(MP_BC_LOAD_METHOD): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
mp_load_method(*sp, qst, sp); mp_load_method(*sp, qst, sp);
sp += 1; sp += 1;
@ -268,10 +282,12 @@ dispatch_loop:
} }
ENTRY(MP_BC_LOAD_BUILD_CLASS): ENTRY(MP_BC_LOAD_BUILD_CLASS):
MARK_EXC_IP_SELECTIVE();
PUSH(mp_load_build_class()); PUSH(mp_load_build_class());
DISPATCH(); DISPATCH();
ENTRY(MP_BC_LOAD_SUBSCR): { ENTRY(MP_BC_LOAD_SUBSCR): {
MARK_EXC_IP_SELECTIVE();
mp_obj_t index = POP(); mp_obj_t index = POP();
SET_TOP(mp_obj_subscr(TOP(), index, MP_OBJ_SENTINEL)); SET_TOP(mp_obj_subscr(TOP(), index, MP_OBJ_SENTINEL));
DISPATCH(); DISPATCH();
@ -290,18 +306,21 @@ dispatch_loop:
} }
ENTRY(MP_BC_STORE_NAME): { ENTRY(MP_BC_STORE_NAME): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
mp_store_name(qst, POP()); mp_store_name(qst, POP());
DISPATCH(); DISPATCH();
} }
ENTRY(MP_BC_STORE_GLOBAL): { ENTRY(MP_BC_STORE_GLOBAL): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
mp_store_global(qst, POP()); mp_store_global(qst, POP());
DISPATCH(); DISPATCH();
} }
ENTRY(MP_BC_STORE_ATTR): { ENTRY(MP_BC_STORE_ATTR): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
mp_store_attr(sp[0], qst, sp[-1]); mp_store_attr(sp[0], qst, sp[-1]);
sp -= 2; sp -= 2;
@ -309,11 +328,13 @@ dispatch_loop:
} }
ENTRY(MP_BC_STORE_SUBSCR): ENTRY(MP_BC_STORE_SUBSCR):
MARK_EXC_IP_SELECTIVE();
mp_obj_subscr(sp[-1], sp[0], sp[-2]); mp_obj_subscr(sp[-1], sp[0], sp[-2]);
sp -= 3; sp -= 3;
DISPATCH(); DISPATCH();
ENTRY(MP_BC_DELETE_FAST): { ENTRY(MP_BC_DELETE_FAST): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
if (fastn[-unum] == MP_OBJ_NULL) { if (fastn[-unum] == MP_OBJ_NULL) {
goto local_name_error; goto local_name_error;
@ -323,6 +344,7 @@ dispatch_loop:
} }
ENTRY(MP_BC_DELETE_DEREF): { ENTRY(MP_BC_DELETE_DEREF): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
if (mp_obj_cell_get(fastn[-unum]) == MP_OBJ_NULL) { if (mp_obj_cell_get(fastn[-unum]) == MP_OBJ_NULL) {
goto local_name_error; goto local_name_error;
@ -332,12 +354,14 @@ dispatch_loop:
} }
ENTRY(MP_BC_DELETE_NAME): { ENTRY(MP_BC_DELETE_NAME): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
mp_delete_name(qst); mp_delete_name(qst);
DISPATCH(); DISPATCH();
} }
ENTRY(MP_BC_DELETE_GLOBAL): { ENTRY(MP_BC_DELETE_GLOBAL): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
mp_delete_global(qst); mp_delete_global(qst);
DISPATCH(); DISPATCH();
@ -417,6 +441,7 @@ dispatch_loop:
} }
ENTRY(MP_BC_SETUP_WITH): { ENTRY(MP_BC_SETUP_WITH): {
MARK_EXC_IP_SELECTIVE();
mp_obj_t obj = TOP(); mp_obj_t obj = TOP();
SET_TOP(mp_load_attr(obj, MP_QSTR___exit__)); SET_TOP(mp_load_attr(obj, MP_QSTR___exit__));
mp_load_method(obj, MP_QSTR___enter__, sp + 1); mp_load_method(obj, MP_QSTR___enter__, sp + 1);
@ -427,6 +452,7 @@ dispatch_loop:
} }
ENTRY(MP_BC_WITH_CLEANUP): { ENTRY(MP_BC_WITH_CLEANUP): {
MARK_EXC_IP_SELECTIVE();
// Arriving here, there's "exception control block" on top of stack, // Arriving here, there's "exception control block" on top of stack,
// and __exit__ bound method underneath it. Bytecode calls __exit__, // and __exit__ bound method underneath it. Bytecode calls __exit__,
// and "deletes" it off stack, shifting "exception control block" // and "deletes" it off stack, shifting "exception control block"
@ -486,6 +512,7 @@ dispatch_loop:
} }
ENTRY(MP_BC_UNWIND_JUMP): { ENTRY(MP_BC_UNWIND_JUMP): {
MARK_EXC_IP_SELECTIVE();
DECODE_SLABEL; DECODE_SLABEL;
PUSH((void*)(ip + slab)); // push destination ip for jump PUSH((void*)(ip + slab)); // push destination ip for jump
PUSH((void*)(mp_uint_t)(*ip)); // push number of exception handlers to unwind (0x80 bit set if we also need to pop stack) PUSH((void*)(mp_uint_t)(*ip)); // push number of exception handlers to unwind (0x80 bit set if we also need to pop stack)
@ -517,11 +544,13 @@ unwind_jump:;
// matched against: POP_BLOCK or POP_EXCEPT (anything else?) // matched against: POP_BLOCK or POP_EXCEPT (anything else?)
ENTRY(MP_BC_SETUP_EXCEPT): ENTRY(MP_BC_SETUP_EXCEPT):
ENTRY(MP_BC_SETUP_FINALLY): { ENTRY(MP_BC_SETUP_FINALLY): {
MARK_EXC_IP_SELECTIVE();
PUSH_EXC_BLOCK((*code_state->ip == MP_BC_SETUP_FINALLY) ? 1 : 0); PUSH_EXC_BLOCK((*code_state->ip == MP_BC_SETUP_FINALLY) ? 1 : 0);
DISPATCH(); DISPATCH();
} }
ENTRY(MP_BC_END_FINALLY): ENTRY(MP_BC_END_FINALLY):
MARK_EXC_IP_SELECTIVE();
// not fully implemented // not fully implemented
// if TOS is an exception, reraises the exception (3 values on TOS) // if TOS is an exception, reraises the exception (3 values on TOS)
// if TOS is None, just pops it and continues // if TOS is None, just pops it and continues
@ -549,10 +578,12 @@ unwind_jump:;
DISPATCH(); DISPATCH();
ENTRY(MP_BC_GET_ITER): ENTRY(MP_BC_GET_ITER):
MARK_EXC_IP_SELECTIVE();
SET_TOP(mp_getiter(TOP())); SET_TOP(mp_getiter(TOP()));
DISPATCH(); DISPATCH();
ENTRY(MP_BC_FOR_ITER): { ENTRY(MP_BC_FOR_ITER): {
MARK_EXC_IP_SELECTIVE();
DECODE_ULABEL; // the jump offset if iteration finishes; for labels are always forward DECODE_ULABEL; // the jump offset if iteration finishes; for labels are always forward
code_state->sp = sp; code_state->sp = sp;
assert(TOP()); assert(TOP());
@ -594,6 +625,7 @@ unwind_jump:;
DISPATCH(); DISPATCH();
ENTRY(MP_BC_BUILD_TUPLE): { ENTRY(MP_BC_BUILD_TUPLE): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
sp -= unum - 1; sp -= unum - 1;
SET_TOP(mp_obj_new_tuple(unum, sp)); SET_TOP(mp_obj_new_tuple(unum, sp));
@ -601,6 +633,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_BUILD_LIST): { ENTRY(MP_BC_BUILD_LIST): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
sp -= unum - 1; sp -= unum - 1;
SET_TOP(mp_obj_new_list(unum, sp)); SET_TOP(mp_obj_new_list(unum, sp));
@ -608,6 +641,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_LIST_APPEND): { ENTRY(MP_BC_LIST_APPEND): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
// I think it's guaranteed by the compiler that sp[unum] is a list // I think it's guaranteed by the compiler that sp[unum] is a list
mp_obj_list_append(sp[-unum], sp[0]); mp_obj_list_append(sp[-unum], sp[0]);
@ -616,17 +650,20 @@ unwind_jump:;
} }
ENTRY(MP_BC_BUILD_MAP): { ENTRY(MP_BC_BUILD_MAP): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
PUSH(mp_obj_new_dict(unum)); PUSH(mp_obj_new_dict(unum));
DISPATCH(); DISPATCH();
} }
ENTRY(MP_BC_STORE_MAP): ENTRY(MP_BC_STORE_MAP):
MARK_EXC_IP_SELECTIVE();
sp -= 2; sp -= 2;
mp_obj_dict_store(sp[0], sp[2], sp[1]); mp_obj_dict_store(sp[0], sp[2], sp[1]);
DISPATCH(); DISPATCH();
ENTRY(MP_BC_MAP_ADD): { ENTRY(MP_BC_MAP_ADD): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
// I think it's guaranteed by the compiler that sp[-unum - 1] is a map // I think it's guaranteed by the compiler that sp[-unum - 1] is a map
mp_obj_dict_store(sp[-unum - 1], sp[0], sp[-1]); mp_obj_dict_store(sp[-unum - 1], sp[0], sp[-1]);
@ -636,6 +673,7 @@ unwind_jump:;
#if MICROPY_PY_BUILTINS_SET #if MICROPY_PY_BUILTINS_SET
ENTRY(MP_BC_BUILD_SET): { ENTRY(MP_BC_BUILD_SET): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
sp -= unum - 1; sp -= unum - 1;
SET_TOP(mp_obj_new_set(unum, sp)); SET_TOP(mp_obj_new_set(unum, sp));
@ -643,6 +681,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_SET_ADD): { ENTRY(MP_BC_SET_ADD): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
// I think it's guaranteed by the compiler that sp[-unum] is a set // I think it's guaranteed by the compiler that sp[-unum] is a set
mp_obj_set_store(sp[-unum], sp[0]); mp_obj_set_store(sp[-unum], sp[0]);
@ -653,6 +692,7 @@ unwind_jump:;
#if MICROPY_PY_BUILTINS_SLICE #if MICROPY_PY_BUILTINS_SLICE
ENTRY(MP_BC_BUILD_SLICE): { ENTRY(MP_BC_BUILD_SLICE): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
if (unum == 2) { if (unum == 2) {
mp_obj_t stop = POP(); mp_obj_t stop = POP();
@ -669,6 +709,7 @@ unwind_jump:;
#endif #endif
ENTRY(MP_BC_UNPACK_SEQUENCE): { ENTRY(MP_BC_UNPACK_SEQUENCE): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
mp_unpack_sequence(sp[0], unum, sp); mp_unpack_sequence(sp[0], unum, sp);
sp += unum - 1; sp += unum - 1;
@ -676,6 +717,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_UNPACK_EX): { ENTRY(MP_BC_UNPACK_EX): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
mp_unpack_ex(sp[0], unum, sp); mp_unpack_ex(sp[0], unum, sp);
sp += (unum & 0xff) + ((unum >> 8) & 0xff); sp += (unum & 0xff) + ((unum >> 8) & 0xff);
@ -715,6 +757,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_CALL_FUNCTION): { ENTRY(MP_BC_CALL_FUNCTION): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
// unum & 0xff == n_positional // unum & 0xff == n_positional
// (unum >> 8) & 0xff == n_keyword // (unum >> 8) & 0xff == n_keyword
@ -724,6 +767,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_CALL_FUNCTION_VAR_KW): { ENTRY(MP_BC_CALL_FUNCTION_VAR_KW): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
// unum & 0xff == n_positional // unum & 0xff == n_positional
// (unum >> 8) & 0xff == n_keyword // (unum >> 8) & 0xff == n_keyword
@ -735,6 +779,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_CALL_METHOD): { ENTRY(MP_BC_CALL_METHOD): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
// unum & 0xff == n_positional // unum & 0xff == n_positional
// (unum >> 8) & 0xff == n_keyword // (unum >> 8) & 0xff == n_keyword
@ -744,6 +789,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_CALL_METHOD_VAR_KW): { ENTRY(MP_BC_CALL_METHOD_VAR_KW): {
MARK_EXC_IP_SELECTIVE();
DECODE_UINT; DECODE_UINT;
// unum & 0xff == n_positional // unum & 0xff == n_positional
// (unum >> 8) & 0xff == n_keyword // (unum >> 8) & 0xff == n_keyword
@ -755,6 +801,7 @@ unwind_jump:;
} }
ENTRY(MP_BC_RETURN_VALUE): ENTRY(MP_BC_RETURN_VALUE):
MARK_EXC_IP_SELECTIVE();
unwind_return: unwind_return:
while (exc_sp >= exc_stack) { while (exc_sp >= exc_stack) {
if (MP_TAGPTR_TAG1(exc_sp->val_sp)) { if (MP_TAGPTR_TAG1(exc_sp->val_sp)) {
@ -778,6 +825,7 @@ unwind_return:
return MP_VM_RETURN_NORMAL; return MP_VM_RETURN_NORMAL;
ENTRY(MP_BC_RAISE_VARARGS): { ENTRY(MP_BC_RAISE_VARARGS): {
MARK_EXC_IP_SELECTIVE();
mp_uint_t unum = *ip++; mp_uint_t unum = *ip++;
mp_obj_t obj; mp_obj_t obj;
assert(unum <= 1); assert(unum <= 1);
@ -810,6 +858,7 @@ yield:
return MP_VM_RETURN_YIELD; return MP_VM_RETURN_YIELD;
ENTRY(MP_BC_YIELD_FROM): { ENTRY(MP_BC_YIELD_FROM): {
MARK_EXC_IP_SELECTIVE();
//#define EXC_MATCH(exc, type) MP_OBJ_IS_TYPE(exc, type) //#define EXC_MATCH(exc, type) MP_OBJ_IS_TYPE(exc, type)
#define EXC_MATCH(exc, type) mp_obj_exception_match(exc, type) #define EXC_MATCH(exc, type) mp_obj_exception_match(exc, type)
#define GENERATOR_EXIT_IF_NEEDED(t) if (t != MP_OBJ_NULL && EXC_MATCH(t, &mp_type_GeneratorExit)) { RAISE(t); } #define GENERATOR_EXIT_IF_NEEDED(t) if (t != MP_OBJ_NULL && EXC_MATCH(t, &mp_type_GeneratorExit)) { RAISE(t); }
@ -862,6 +911,7 @@ yield:
} }
ENTRY(MP_BC_IMPORT_NAME): { ENTRY(MP_BC_IMPORT_NAME): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
mp_obj_t obj = POP(); mp_obj_t obj = POP();
SET_TOP(mp_import_name(qst, obj, TOP())); SET_TOP(mp_import_name(qst, obj, TOP()));
@ -869,6 +919,7 @@ yield:
} }
ENTRY(MP_BC_IMPORT_FROM): { ENTRY(MP_BC_IMPORT_FROM): {
MARK_EXC_IP_SELECTIVE();
DECODE_QSTR; DECODE_QSTR;
mp_obj_t obj = mp_import_from(TOP(), qst); mp_obj_t obj = mp_import_from(TOP(), qst);
PUSH(obj); PUSH(obj);
@ -876,6 +927,7 @@ yield:
} }
ENTRY(MP_BC_IMPORT_STAR): ENTRY(MP_BC_IMPORT_STAR):
MARK_EXC_IP_SELECTIVE();
mp_import_all(POP()); mp_import_all(POP());
DISPATCH(); DISPATCH();
@ -893,10 +945,12 @@ yield:
DISPATCH(); DISPATCH();
ENTRY(MP_BC_UNARY_OP_MULTI): ENTRY(MP_BC_UNARY_OP_MULTI):
MARK_EXC_IP_SELECTIVE();
SET_TOP(mp_unary_op(ip[-1] - MP_BC_UNARY_OP_MULTI, TOP())); SET_TOP(mp_unary_op(ip[-1] - MP_BC_UNARY_OP_MULTI, TOP()));
DISPATCH(); DISPATCH();
ENTRY(MP_BC_BINARY_OP_MULTI): { ENTRY(MP_BC_BINARY_OP_MULTI): {
MARK_EXC_IP_SELECTIVE();
mp_obj_t rhs = POP(); mp_obj_t rhs = POP();
mp_obj_t lhs = TOP(); mp_obj_t lhs = TOP();
SET_TOP(mp_binary_op(ip[-1] - MP_BC_BINARY_OP_MULTI, lhs, rhs)); SET_TOP(mp_binary_op(ip[-1] - MP_BC_BINARY_OP_MULTI, lhs, rhs));
@ -904,6 +958,7 @@ yield:
} }
ENTRY_DEFAULT: ENTRY_DEFAULT:
MARK_EXC_IP_SELECTIVE();
#else #else
ENTRY_DEFAULT: ENTRY_DEFAULT:
if (ip[-1] < MP_BC_LOAD_CONST_SMALL_INT_MULTI + 64) { if (ip[-1] < MP_BC_LOAD_CONST_SMALL_INT_MULTI + 64) {
@ -938,6 +993,7 @@ yield:
pending_exception_check: pending_exception_check:
if (mp_pending_exception != MP_OBJ_NULL) { if (mp_pending_exception != MP_OBJ_NULL) {
MARK_EXC_IP_SELECTIVE();
mp_obj_t obj = mp_pending_exception; mp_obj_t obj = mp_pending_exception;
mp_pending_exception = MP_OBJ_NULL; mp_pending_exception = MP_OBJ_NULL;
RAISE(obj); RAISE(obj);