Speed-up dictionary constructor by about 10%.
New opcode, STORE_MAP saves the compiler from awkward stack manipulations
and specializes for dicts using PyDict_SetItem instead of PyObject_SetItem.
Old disassembly:
0 BUILD_MAP 0
3 DUP_TOP
4 LOAD_CONST 1 (1)
7 ROT_TWO
8 LOAD_CONST 2 ('x')
11 STORE_SUBSCR
12 DUP_TOP
13 LOAD_CONST 3 (2)
16 ROT_TWO
17 LOAD_CONST 4 ('y')
20 STORE_SUBSCR
New disassembly:
0 BUILD_MAP 0
3 LOAD_CONST 1 (1)
6 LOAD_CONST 2 ('x')
9 STORE_MAP
10 LOAD_CONST 3 (2)
13 LOAD_CONST 4 ('y')
16 STORE_MAP
diff --git a/Lib/opcode.py b/Lib/opcode.py
index 095ca42..c3457d0 100644
--- a/Lib/opcode.py
+++ b/Lib/opcode.py
@@ -85,6 +85,7 @@
def_op('DELETE_SLICE+2', 52)
def_op('DELETE_SLICE+3', 53)
+def_op('STORE_MAP', 54)
def_op('INPLACE_ADD', 55)
def_op('INPLACE_SUBTRACT', 56)
def_op('INPLACE_MULTIPLY', 57)