summaryrefslogtreecommitdiffstats
path: root/Include/cpython/code.h
diff options
context:
space:
mode:
authorEric Snow <ericsnowcurrently@gmail.com>2021-06-07 22:52:00 (GMT)
committerGitHub <noreply@github.com>2021-06-07 22:52:00 (GMT)
commit631f9938b1604d4f893417ec339b9e0fa9196fb1 (patch)
tree6a72bf35dafb42ad3d00e153e244538db4a646ee /Include/cpython/code.h
parente915db3e9e512249a6f494c0b331db2d021e1f56 (diff)
downloadcpython-631f9938b1604d4f893417ec339b9e0fa9196fb1.zip
cpython-631f9938b1604d4f893417ec339b9e0fa9196fb1.tar.gz
cpython-631f9938b1604d4f893417ec339b9e0fa9196fb1.tar.bz2
bpo-43693: Add the MAKE_CELL opcode and interleave fast locals offsets. (gh-26396)
This moves logic out of the frame initialization code and into the compiler and eval loop. Doing so simplifies the runtime code and allows us to optimize it better. https://bugs.python.org/issue43693
Diffstat (limited to 'Include/cpython/code.h')
-rw-r--r--Include/cpython/code.h11
1 files changed, 9 insertions, 2 deletions
diff --git a/Include/cpython/code.h b/Include/cpython/code.h
index c81f9f3..a338374 100644
--- a/Include/cpython/code.h
+++ b/Include/cpython/code.h
@@ -2,9 +2,16 @@
# error "this header file must not be included directly"
#endif
+/* Each instruction in a code object is a fixed-width value,
+ * currently 2 bytes: 1-byte opcode + 1-byte oparg. The EXTENDED_ARG
+ * opcode allows for larger values but the current limit is 3 uses
+ * of EXTENDED_ARG (see Python/wordcode_helpers.h), for a maximum
+ * 32-bit value. This aligns with the note in Python/compile.c
+ * (compiler_addop_i_line) indicating that the max oparg value is
+ * 2**32 - 1, rather than INT_MAX.
+ */
+
typedef uint16_t _Py_CODEUNIT;
-// Each oparg must fit in the second half of _Py_CODEUNIT, hence 8 bits.
-#define _Py_MAX_OPARG 255
#ifdef WORDS_BIGENDIAN
# define _Py_OPCODE(word) ((word) >> 8)