diff options
Diffstat (limited to 'Python')
| -rw-r--r-- | Python/codegen.c | 78 | ||||
| -rw-r--r-- | Python/marshal.c | 34 |
2 files changed, 93 insertions, 19 deletions
diff --git a/Python/codegen.c b/Python/codegen.c index 896c30cc149..689d2b5124e 100644 --- a/Python/codegen.c +++ b/Python/codegen.c @@ -194,6 +194,7 @@ static int codegen_visit_expr(compiler *, expr_ty); static int codegen_augassign(compiler *, stmt_ty); static int codegen_annassign(compiler *, stmt_ty); static int codegen_subscript(compiler *, expr_ty); +static int codegen_slice_two_parts(compiler *, expr_ty); static int codegen_slice(compiler *, expr_ty); static bool are_all_items_const(asdl_expr_seq *, Py_ssize_t, Py_ssize_t); @@ -5005,12 +5006,8 @@ codegen_visit_expr(compiler *c, expr_ty e) } break; case Slice_kind: - { - int n = codegen_slice(c, e); - RETURN_IF_ERROR(n); - ADDOP_I(c, loc, BUILD_SLICE, n); + RETURN_IF_ERROR(codegen_slice(c, e)); break; - } case Name_kind: return codegen_nameop(c, loc, e->v.Name.id, e->v.Name.ctx); /* child nodes of List and Tuple will have expr_context set */ @@ -5023,9 +5020,22 @@ codegen_visit_expr(compiler *c, expr_ty e) } static bool -is_two_element_slice(expr_ty s) +is_constant_slice(expr_ty s) { return s->kind == Slice_kind && + (s->v.Slice.lower == NULL || + s->v.Slice.lower->kind == Constant_kind) && + (s->v.Slice.upper == NULL || + s->v.Slice.upper->kind == Constant_kind) && + (s->v.Slice.step == NULL || + s->v.Slice.step->kind == Constant_kind); +} + +static bool +should_apply_two_element_slice_optimization(expr_ty s) +{ + return !is_constant_slice(s) && + s->kind == Slice_kind && s->v.Slice.step == NULL; } @@ -5046,8 +5056,8 @@ codegen_augassign(compiler *c, stmt_ty s) break; case Subscript_kind: VISIT(c, expr, e->v.Subscript.value); - if (is_two_element_slice(e->v.Subscript.slice)) { - RETURN_IF_ERROR(codegen_slice(c, e->v.Subscript.slice)); + if (should_apply_two_element_slice_optimization(e->v.Subscript.slice)) { + RETURN_IF_ERROR(codegen_slice_two_parts(c, e->v.Subscript.slice)); ADDOP_I(c, loc, COPY, 3); ADDOP_I(c, loc, COPY, 3); ADDOP_I(c, loc, COPY, 3); @@ -5084,7 +5094,7 @@ codegen_augassign(compiler *c, stmt_ty s) ADDOP_NAME(c, loc, STORE_ATTR, e->v.Attribute.attr, names); break; case Subscript_kind: - if (is_two_element_slice(e->v.Subscript.slice)) { + if (should_apply_two_element_slice_optimization(e->v.Subscript.slice)) { ADDOP_I(c, loc, SWAP, 4); ADDOP_I(c, loc, SWAP, 3); ADDOP_I(c, loc, SWAP, 2); @@ -5231,8 +5241,10 @@ codegen_subscript(compiler *c, expr_ty e) } VISIT(c, expr, e->v.Subscript.value); - if (is_two_element_slice(e->v.Subscript.slice) && ctx != Del) { - RETURN_IF_ERROR(codegen_slice(c, e->v.Subscript.slice)); + if (should_apply_two_element_slice_optimization(e->v.Subscript.slice) && + ctx != Del + ) { + RETURN_IF_ERROR(codegen_slice_two_parts(c, e->v.Subscript.slice)); if (ctx == Load) { ADDOP(c, loc, BINARY_SLICE); } @@ -5254,15 +5266,9 @@ codegen_subscript(compiler *c, expr_ty e) return SUCCESS; } -/* Returns the number of the values emitted, - * thus are needed to build the slice, or -1 if there is an error. */ static int -codegen_slice(compiler *c, expr_ty s) +codegen_slice_two_parts(compiler *c, expr_ty s) { - int n = 2; - assert(s->kind == Slice_kind); - - /* only handles the cases where BUILD_SLICE is emitted */ if (s->v.Slice.lower) { VISIT(c, expr, s->v.Slice.lower); } @@ -5277,11 +5283,45 @@ codegen_slice(compiler *c, expr_ty s) ADDOP_LOAD_CONST(c, LOC(s), Py_None); } + return 0; +} + +static int +codegen_slice(compiler *c, expr_ty s) +{ + int n = 2; + assert(s->kind == Slice_kind); + + if (is_constant_slice(s)) { + PyObject *start = NULL; + if (s->v.Slice.lower) { + start = s->v.Slice.lower->v.Constant.value; + } + PyObject *stop = NULL; + if (s->v.Slice.upper) { + stop = s->v.Slice.upper->v.Constant.value; + } + PyObject *step = NULL; + if (s->v.Slice.step) { + step = s->v.Slice.step->v.Constant.value; + } + PyObject *slice = PySlice_New(start, stop, step); + if (slice == NULL) { + return ERROR; + } + ADDOP_LOAD_CONST_NEW(c, LOC(s), slice); + return SUCCESS; + } + + RETURN_IF_ERROR(codegen_slice_two_parts(c, s)); + if (s->v.Slice.step) { n++; VISIT(c, expr, s->v.Slice.step); } - return n; + + ADDOP_I(c, LOC(s), BUILD_SLICE, n); + return SUCCESS; } diff --git a/Python/marshal.c b/Python/marshal.c index b1708a7306f..3d127b4e331 100644 --- a/Python/marshal.c +++ b/Python/marshal.c @@ -76,6 +76,7 @@ module marshal #define TYPE_UNKNOWN '?' #define TYPE_SET '<' #define TYPE_FROZENSET '>' +#define TYPE_SLICE ':' #define FLAG_REF '\x80' /* with a type, add obj to index */ #define TYPE_ASCII 'a' @@ -613,6 +614,13 @@ w_complex_object(PyObject *v, char flag, WFILE *p) w_pstring(view.buf, view.len, p); PyBuffer_Release(&view); } + else if (PySlice_Check(v)) { + PySliceObject *slice = (PySliceObject *)v; + W_TYPE(TYPE_SLICE, p); + w_object(slice->start, p); + w_object(slice->stop, p); + w_object(slice->step, p); + } else { W_TYPE(TYPE_UNKNOWN, p); p->error = WFERR_UNMARSHALLABLE; @@ -1534,6 +1542,32 @@ r_object(RFILE *p) retval = Py_NewRef(v); break; + case TYPE_SLICE: + { + Py_ssize_t idx = r_ref_reserve(flag, p); + PyObject *stop = NULL; + PyObject *step = NULL; + PyObject *start = r_object(p); + if (start == NULL) { + goto cleanup; + } + stop = r_object(p); + if (stop == NULL) { + goto cleanup; + } + step = r_object(p); + if (step == NULL) { + goto cleanup; + } + retval = PySlice_New(start, stop, step); + r_ref_insert(retval, idx, flag, p); + cleanup: + Py_XDECREF(start); + Py_XDECREF(stop); + Py_XDECREF(step); + break; + } + default: /* Bogus data got written, which isn't ideal. This will let you keep working and recover. */ |