Use slot offsets for opargs

python · brandtbucher · Oct 27, 2021 · Oct 27, 2021 · Oct 27, 2021 · Oct 27, 2021
commit befdc3f914e0b2828d67951b119bb6a8abcd69bf
diff --git a/Include/cpython/object.h b/Include/cpython/object.h
@@ -123,7 +123,7 @@ typedef struct {
     binaryfunc nb_xor;
     binaryfunc nb_or;
     unaryfunc nb_int;
-    void *nb_reserved;  /* the slot formerly known as nb_long */
+    unaryfunc nb_reserved;  /* the slot formerly known as nb_long */
     unaryfunc nb_float;
 
     binaryfunc nb_inplace_add;

diff --git a/Include/opcode.h b/Include/opcode.h
diff --git a/Lib/dis.py b/Lib/dis.py
@@ -7,7 +7,7 @@
 
 from opcode import *
 from opcode import __all__ as _opcodes_all
-from opcode import _nb_ops
+from opcode import _nb_slots
 
 __all__ = ["code_info", "dis", "disassemble", "distb", "disco",
            "findlinestarts", "findlabels", "show_code",
@@ -30,12 +30,11 @@
 LOAD_CONST = opmap['LOAD_CONST']
 
 BINARY_OP = opmap['BINARY_OP']
-BINARY_OPS = [name for _, name in _nb_ops]
-
 INPLACE_OP = opmap['INPLACE_OP']
-INPLACE_OPS = [f"{name}=" for _, name in _nb_ops]
 
-del _nb_ops
+NB_NAMES = {i: name for i, _, name in _nb_slots}
+
+del _nb_slots
 
 def _try_compile(source, name):
     """Attempts to compile the given source, first as an expression and
@@ -455,10 +454,8 @@ def _get_instructions_bytes(code, varname_from_oparg=None,
             elif op == MAKE_FUNCTION:
                 argrepr = ', '.join(s for i, s in enumerate(MAKE_FUNCTION_FLAGS)
                                     if arg & (1<<i))
-            elif op == BINARY_OP:
-                argrepr = BINARY_OPS[arg]
-            elif op == INPLACE_OP:
-                argrepr = INPLACE_OPS[arg]
+            elif op == BINARY_OP or op == INPLACE_OP:
+                argrepr = NB_NAMES[arg]
         yield Instruction(opname[op], op,
                           arg, argval, argrepr,
                           offset, starts_line, is_jump_target, positions)

diff --git a/Lib/opcode.py b/Lib/opcode.py
@@ -205,16 +205,43 @@ def jabs_op(name, op):
 
 del def_op, name_op, jrel_op, jabs_op
 
-_nb_ops = [
-    ("NB_AND", "&"),
-    ("NB_FLOOR_DIVIDE", "//"),
-    ("NB_LSHIFT", "<<"),
-    ("NB_MATRIX_MULTIPLY", "@"),
-    ("NB_OR", "|"),
-    ("NB_RSHIFT", ">>"),
-    ("NB_SUBTRACT", "-"),
-    ("NB_TRUE_DIVIDE", "/"),
-    ("NB_XOR", "^"),
+_nb_slots = [
+    # nb_add
+    (1, "nb_subtract", "-"),
+    # nb_multiply
+    # nb_remainder
+    # nb_divmod
+    # nb_power
+    # nb_negative
+    # nb_positive
+    # nb_absolute
+    # nb_bool
+    # nb_invert
+    (11, "nb_lshift", "<<"),
+    (12, "nb_rshift", ">>"),
+    (13, "nb_and", "&"),
+    (14, "nb_xor", "^"),
+    (15, "nb_or", "|"),
+    # nb_int
+    # nb_reserved
+    # nb_float
+    # nb_inplace_add
+    (20, "nb_inplace_subtract", "-="),
+    # nb_inplace_multiply
+    # nb_inplace_remainder
+    # nb_inplace_power
+    (24, "nb_inplace_lshift", "<<="),
+    (25, "nb_inplace_rshift", ">>="),
+    (26, "nb_inplace_and", "&="),
+    (27, "nb_inplace_xor", "^="),
+    (28, "nb_inplace_or", "|="),
+    (29, "nb_floor_divide", "//"),
+    (30, "nb_true_divide", "/"),
+    (31, "nb_inplace_floor_divide", "//="),
+    (32, "nb_inplace_true_divide", "/="),
+    # nb_index
+    (34, "nb_matrix_multiply", "@"),
+    (35, "nb_inplace_matrix_multiply", "@="),
 ]
 
 _specialized_instructions = [

diff --git a/Lib/test/test_dis.py b/Lib/test/test_dis.py
@@ -285,7 +285,7 @@ def bug42562():
 
 %3d           2 LOAD_CONST               1 (1)
               4 LOAD_CONST               2 (0)
-    -->       6 BINARY_OP                7 (/)
+    -->       6 BINARY_OP               30 (/)
               8 POP_TOP
 
 %3d          10 LOAD_FAST                1 (tb)
@@ -1060,7 +1060,7 @@ def _prepare_test_cases():
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=62, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=64, starts_line=13, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=5, argval=1, argrepr='1', offset=66, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='INPLACE_OP', opcode=123, arg=6, argval=6, argrepr='-=', offset=68, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='INPLACE_OP', opcode=123, arg=20, argval=20, argrepr='-=', offset=68, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='STORE_FAST', opcode=125, arg=0, argval='i', argrepr='i', offset=70, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=72, starts_line=14, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=3, argval=6, argrepr='6', offset=74, starts_line=None, is_jump_target=False, positions=None),
@@ -1081,7 +1081,7 @@ def _prepare_test_cases():
   Instruction(opname='NOP', opcode=9, arg=None, argval=None, argrepr='', offset=104, starts_line=20, is_jump_target=True, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=5, argval=1, argrepr='1', offset=106, starts_line=21, is_jump_target=False, positions=None),
   Instruction(opname='LOAD_CONST', opcode=100, arg=7, argval=0, argrepr='0', offset=108, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='BINARY_OP', opcode=122, arg=7, argval=7, argrepr='/', offset=110, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='BINARY_OP', opcode=122, arg=30, argval=30, argrepr='/', offset=110, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=112, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='JUMP_FORWARD', opcode=110, arg=15, argval=146, argrepr='to 146', offset=114, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=116, starts_line=None, is_jump_target=False, positions=None),

diff --git a/Objects/abstract.c b/Objects/abstract.c
@@ -1715,44 +1715,51 @@ PyNumber_ToBase(PyObject *n, int base)
     return res;
 }
 
-typedef struct {
-    const int slot;
-    const char name[3];
-    const int islot;
-    const char iname[4];
-} nb_info;
-
-#define NB_INFO(name, slot) \
-    {NB_SLOT(nb_##slot), name, NB_SLOT(nb_inplace_##slot), name "="}
-
-static nb_info nb_infos[] = {
-    [NB_AND] = NB_INFO("&", and),
-    [NB_FLOOR_DIVIDE] = NB_INFO("//", floor_divide),
-    [NB_LSHIFT] = NB_INFO("<<", lshift),
-    [NB_MATRIX_MULTIPLY] = NB_INFO("@", matrix_multiply),
-    [NB_OR] = NB_INFO("|", or),
-    [NB_RSHIFT] = NB_INFO(">>", rshift),
-    [NB_SUBTRACT] = NB_INFO("-", subtract),
-    [NB_TRUE_DIVIDE] = NB_INFO("/", true_divide),
-    [NB_XOR] = NB_INFO("^", xor),
+#define NB_NAMES(op)                           \
+    [NB_##op] = NB_##op##_NAME,                \
+    [NB_INPLACE_##op] = NB_INPLACE_##op##_NAME
+
+static const char nb_names[][4] = {
+    NB_NAMES(AND),
+    NB_NAMES(FLOOR_DIVIDE),
+    NB_NAMES(LSHIFT),
+    NB_NAMES(MATRIX_MULTIPLY),
+    NB_NAMES(OR),
+    NB_NAMES(RSHIFT),
+    NB_NAMES(SUBTRACT),
+    NB_NAMES(TRUE_DIVIDE),
+    NB_NAMES(XOR),
 };
 
-#undef NB_INFO
+#undef NB_NAMES
+
+#define NB_BINSLOT(op) [NB_INPLACE_##op] = NB_##op
+
+static const uint8_t nb_binary_slots[] = {
+    NB_BINSLOT(AND),
+    NB_BINSLOT(FLOOR_DIVIDE),
+    NB_BINSLOT(LSHIFT),
+    NB_BINSLOT(MATRIX_MULTIPLY),
+    NB_BINSLOT(OR),
+    NB_BINSLOT(RSHIFT),
+    NB_BINSLOT(SUBTRACT),
+    NB_BINSLOT(TRUE_DIVIDE),
+    NB_BINSLOT(XOR),
+};
+
+#undef NB_BINSLOT
 
 PyObject *
 _PyNumber_Op(PyObject *o1, PyObject *o2, unsigned op)
 {
-    assert(op < sizeof(nb_infos) / sizeof(nb_info));
-    nb_info *ni = &nb_infos[op];
-    return binary_op(o1, o2, ni->slot, ni->name);
+    return binary_op(o1, o2, op * NB_SCALE, nb_names[op]);
 }
 
 PyObject *
 _PyNumber_InPlaceOp(PyObject *o1, PyObject *o2, unsigned op)
 {
-    assert(op < sizeof(nb_infos) / sizeof(nb_info));
-    nb_info *ni = &nb_infos[op];
-    return binary_iop(o1, o2, ni->islot, ni->slot, ni->iname);
+    return binary_iop(o1, o2, op * NB_SCALE, nb_binary_slots[op] * NB_SCALE,
+                      nb_names[op]);
 }
 
 

@@ -3684,24 +3684,25 @@ unaryop(unaryop_ty op)
 static int
 addop_binary(struct compiler *c, operator_ty binop, bool inplace)
 {
+    assert(HAVE_SANE_NB_OFFSETS);
     int oparg;
     switch (binop) {
         case Add:
             // Addition interacts with sq_concat:
             ADDOP(c, inplace ? INPLACE_ADD : BINARY_ADD);
             return 1;
         case Sub:
-            oparg = NB_SUBTRACT;
+            oparg = inplace ? NB_INPLACE_SUBTRACT : NB_SUBTRACT;
             break;
         case Mult:
             // Multiplication interacts with sq_repeat:
             ADDOP(c, inplace ? INPLACE_MULTIPLY : BINARY_MULTIPLY);
             return 1;
         case MatMult:
-            oparg = NB_MATRIX_MULTIPLY;
+            oparg = inplace ? NB_INPLACE_MATRIX_MULTIPLY : NB_MATRIX_MULTIPLY;
             break;
         case Div:
-            oparg = NB_TRUE_DIVIDE;
+            oparg = inplace ? NB_INPLACE_TRUE_DIVIDE : NB_TRUE_DIVIDE;
             break;
         case Mod:
             // Modulation contains a fast path for strings:
@@ -3712,22 +3713,22 @@ addop_binary(struct compiler *c, operator_ty binop, bool inplace)
             ADDOP(c, inplace ? INPLACE_POWER : BINARY_POWER);
             return 1;
         case LShift:
-            oparg = NB_LSHIFT;
+            oparg = inplace ? NB_INPLACE_LSHIFT : NB_LSHIFT;
             break;
         case RShift:
-            oparg = NB_RSHIFT;
+            oparg = inplace ? NB_INPLACE_RSHIFT : NB_RSHIFT;
             break;
         case BitOr:
-            oparg = NB_OR;
+            oparg = inplace ? NB_INPLACE_OR : NB_OR;
             break;
         case BitXor:
-            oparg = NB_XOR;
+            oparg = inplace ? NB_INPLACE_XOR : NB_XOR;
             break;
         case BitAnd:
-            oparg = NB_AND;
+            oparg = inplace ? NB_INPLACE_AND : NB_AND;
             break;
         case FloorDiv:
-            oparg = NB_FLOOR_DIVIDE;
+            oparg = inplace ? NB_INPLACE_FLOOR_DIVIDE : NB_FLOOR_DIVIDE;
             break;
         default:
             PyErr_Format(PyExc_SystemError, "%s op %d should not be possible",

diff --git a/Tools/scripts/generate_opcode_h.py b/Tools/scripts/generate_opcode_h.py
@@ -11,11 +11,15 @@
 extern "C" {
 #endif
 
+#include <stddef.h>
+
 
 /* Instruction opcodes for compiled code */
 """.lstrip()
 
 footer = """
+#define NB_SCALE offsetof(PyNumberMethods, nb_subtract)
+
 #define HAS_ARG(op) ((op) >= HAVE_ARGUMENT)
 
 /* Reserve some bytecodes for internal use in the compiler.
@@ -86,8 +90,18 @@ def main(opcode_py, outfile='Include/opcode.h'):
         fobj.write("\n    )\n")
 
         fobj.write("\n")
-        for i, (op, _) in enumerate(opcode["_nb_ops"]):
-            fobj.write(DEFINE.format(op, i))
+        for i, slot, _ in opcode["_nb_slots"]:
+            fobj.write(DEFINE.format(slot.upper(), i))
+
+        fobj.write("\n")
+        for _, slot, name in opcode["_nb_slots"]:
+            fobj.write(DEFINE.format(f"{slot.upper()}_NAME", f'"{name}"'))
+
+        fobj.write("\n")
+        fobj.write("#define HAVE_SANE_NB_OFFSETS ( \\\n")
+        for _, slot, _ in opcode["_nb_slots"]:
+            fobj.write(f"    {slot.upper()} * NB_SCALE == offsetof(PyNumberMethods, {slot}) && \\\n")
+        fobj.write("    true)\n")
 
         fobj.write(footer)