py/qstr: Add support for sorted qstr pools.

This provides a significant performance boost for qstr_find_strn, which is
called a lot during parsing and loading of .mpy files, as well as interning
of string objects (which happens in most string methods that return new
strings).

Also adds comments to explain the "static" qstrs.  These are part of the
.mpy ABI and avoid needing to duplicate string data for QSTRs known to
already be in the firmware.  The static pool isn't currently sorted, but in
the future we could either split the static pool into the sorted regions,
or in the next .mpy version just sort them.

Based on initial work done by @amirgon in #6896.

This work was funded through GitHub Sponsors.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>

py/makeqstrdata.py

@@ -52,7 +52,8 @@ codepoint2name[ord("^")] = "caret"
 codepoint2name[ord("|")] = "pipe"
 codepoint2name[ord("~")] = "tilde"
 
-# static qstrs, should be sorted
+# static qstrs, these must maintain a specific order for .mpy compatibility
+# See QSTR_LAST_STATIC at the top of py/persistentcode.c
 
 static_qstr_list = [
     "",
@@ -222,6 +223,71 @@ static_qstr_list = [
     "zip",
 ]
 
+# Additional QSTRs that must have index <255 because they are stored in
+# `mp_binary_op_method_name` and `mp_unary_op_method_name` (see py/objtype.c).
+# These are not part of the .mpy compatibility list, but we place them in the
+# fixed unsorted pool (i.e. QDEF0) to ensure their indices are small.
+operator_qstr_list = {
+    "__bool__",
+    "__pos__",
+    "__neg__",
+    "__invert__",
+    "__abs__",
+    "__float__",
+    "__complex__",
+    "__sizeof__",
+    "__lt__",
+    "__gt__",
+    "__eq__",
+    "__le__",
+    "__ge__",
+    "__ne__",
+    "__contains__",
+    "__iadd__",
+    "__isub__",
+    "__imul__",
+    "__imatmul__",
+    "__ifloordiv__",
+    "__itruediv__",
+    "__imod__",
+    "__ipow__",
+    "__ior__",
+    "__ixor__",
+    "__iand__",
+    "__ilshift__",
+    "__irshift__",
+    "__add__",
+    "__sub__",
+    "__mul__",
+    "__matmul__",
+    "__floordiv__",
+    "__truediv__",
+    "__mod__",
+    "__divmod__",
+    "__pow__",
+    "__or__",
+    "__xor__",
+    "__and__",
+    "__lshift__",
+    "__rshift__",
+    "__radd__",
+    "__rsub__",
+    "__rmul__",
+    "__rmatmul__",
+    "__rfloordiv__",
+    "__rtruediv__",
+    "__rmod__",
+    "__rpow__",
+    "__ror__",
+    "__rxor__",
+    "__rand__",
+    "__rlshift__",
+    "__rrshift__",
+    "__get__",
+    "__set__",
+    "__delete__",
+}
+
 
 # this must match the equivalent function in qstr.c
 def compute_hash(qstr, bytes_hash):
@@ -244,22 +310,13 @@ def qstr_escape(qst):
     return re.sub(r"[^A-Za-z0-9_]", esc_char, qst)
 
 
+static_qstr_list_ident = list(map(qstr_escape, static_qstr_list))
+
+
 def parse_input_headers(infiles):
     qcfgs = {}
     qstrs = {}
 
-    # add static qstrs
-    for qstr in static_qstr_list:
-        # work out the corresponding qstr name
-        ident = qstr_escape(qstr)
-
-        # don't add duplicates
-        assert ident not in qstrs
-
-        # add the qstr to the list, with order number to retain original order in file
-        order = len(qstrs) - 300000
-        qstrs[ident] = (order, ident, qstr)
-
     # read the qstrs in from the input files
     for infile in infiles:
         with open(infile, "rt") as f:
@@ -294,22 +351,12 @@ def parse_input_headers(infiles):
                 ident = qstr_escape(qstr)
 
                 # don't add duplicates
+                if ident in static_qstr_list_ident:
+                    continue
                 if ident in qstrs:
                     continue
 
-                # add the qstr to the list, with order number to retain original order in file
-                order = len(qstrs)
-                # but put special method names like __add__ at the top of list, so
-                # that their id's fit into a byte
-                if ident == "":
-                    # Sort empty qstr above all still
-                    order = -200000
-                elif ident == "__dir__":
-                    # Put __dir__ after empty qstr for builtin dir() to work
-                    order = -190000
-                elif ident.startswith("__"):
-                    order -= 100000
-                qstrs[ident] = (order, ident, qstr)
+                qstrs[ident] = (ident, qstr)
 
     if not qcfgs:
         sys.stderr.write("ERROR: Empty preprocessor output - check for errors above\n")
@@ -348,12 +395,19 @@ def print_qstr_data(qcfgs, qstrs):
     print("")
 
     # add NULL qstr with no hash or data
-    print('QDEF(MP_QSTRnull, 0, 0, "")')
+    print('QDEF0(MP_QSTRnull, 0, 0, "")')
 
-    # go through each qstr and print it out
-    for order, ident, qstr in sorted(qstrs.values(), key=lambda x: x[0]):
+    # add static qstrs to the first unsorted pool
+    for qstr in static_qstr_list:
         qbytes = make_bytes(cfg_bytes_len, cfg_bytes_hash, qstr)
-        print("QDEF(MP_QSTR_%s, %s)" % (ident, qbytes))
+        print("QDEF0(MP_QSTR_%s, %s)" % (qstr_escape(qstr), qbytes))
+
+    # add remaining qstrs to the sorted (by value) pool (unless they're in
+    # operator_qstr_list, in which case add them to the unsorted pool)
+    for ident, qstr in sorted(qstrs.values(), key=lambda x: x[1]):
+        qbytes = make_bytes(cfg_bytes_len, cfg_bytes_hash, qstr)
+        pool = 0 if qstr in operator_qstr_list else 1
+        print("QDEF%d(MP_QSTR_%s, %s)" % (pool, ident, qbytes))
 
 
 def do_work(infiles):