Teach the peephole optimizer to fold simple constant expressions.
diff --git a/Lib/test/test_peepholer.py b/Lib/test/test_peepholer.py
index f58fe03..a0031f2 100644
--- a/Lib/test/test_peepholer.py
+++ b/Lib/test/test_peepholer.py
@@ -102,6 +102,34 @@
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
],)
+ def test_folding_of_binops_on_constants(self):
+ for line, elem in (
+ ('a = 2+3+4', '(9)'), # chained fold
+ ('"@"*4', "('@@@@')"), # check string ops
+ ('a="abc" + "def"', "('abcdef')"), # check string ops
+ ('a = 3**4', '(81)'), # binary power
+ ('a = 3*4', '(12)'), # binary multiply
+ ('a = 13/4.0', '(3.25)'), # binary divide
+ ('a = 13//4', '(3)'), # binary floor divide
+ ('a = 14%4', '(2)'), # binary modulo
+ ('a = 2+3', '(5)'), # binary add
+ ('a = 13-4', '(9)'), # binary subtract
+ ('a = (12,13)[1]', '(13)'), # binary subscr
+ ('a = 13 << 2', '(52)'), # binary lshift
+ ('a = 13 >> 2', '(3)'), # binary rshift
+ ('a = 13 & 7', '(5)'), # binary and
+ ('a = 13 ^ 7', '(10)'), # binary xor
+ ('a = 13 | 7', '(15)'), # binary or
+ ):
+ asm = dis_single(line)
+ self.assert_(elem in asm, asm)
+ self.assert_('BINARY_' not in asm)
+
+ # Verify that unfoldables are skipped
+ asm = dis_single('a=2+"b"')
+ self.assert_('(2)' in asm)
+ self.assert_("('b')" in asm)
+
def test_elim_extra_return(self):
# RETURN LOAD_CONST None RETURN --> RETURN
def f(x):