LSL-PyOptimizer/lslopt/lsllastpass.py
2024-04-14 11:40:21 +02:00

247 lines
9.2 KiB
Python

# (C) Copyright 2015-2024 Sei Lisa. All rights reserved.
#
# This file is part of LSL PyOptimizer.
#
# LSL PyOptimizer is free software: you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# LSL PyOptimizer is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with LSL PyOptimizer. If not, see <http://www.gnu.org/licenses/>.
# Optimizations that have a negative effect on other stages.
from lslopt import lslcommon
from lslopt.lslcommon import nr
#from lslcommon import Vector, Quaternion
#import lslfuncs
#from lslfuncs import ZERO_VECTOR, ZERO_ROTATION
#import math
#from lslparse import warning
#from lslfuncopt import OptimizeFunc, OptimizeArgs, FuncOptSetup
from strutil import xrange
class rec:
def __init__(self, **init):
for i in init:
setattr(self, i, init[i])
class lastpass(object):
def visible(self, scope):
return scope in self.scopeStack
def LastPassPreOrder(self, parent, index):
node = parent[index]
nt = node.nt
child = node.ch
if (nt != '{}' and nt != ';' and nt != 'LAMBDA' and nt != '@'
and not self.inExpr
):
# Node that generates code.
# EXPR counts as a single statement for JUMP purposes.
self.prevStmt = self.lastStmt
self.lastStmt = rec(node=node, parent=parent, index=index)
# These are all the labels that label the current statement
self.lastLabels = self.curLabels
self.curLabels = set()
if nt == 'EXPR':
self.inExpr = True
return
if (self.optlistadd and not self.globalmode
and (nt == 'CONST' and node.t == 'list' or nt == 'LIST'
or nt == '+' and child[0].t == 'list' and
(child[1].nt == 'CONST' and child[1].t == 'list'
or child[1].nt == 'LIST')
)
):
# Perform these transformations if the list is SEF:
# [a, b, ...] -> (list)a + b...
# ListExpr + [a, b, ..] -> ListExpr + a + b...
# (ListExpr doesn't need to be SEF for this to work)
# This transformation makes it difficult to handle lists during
# optimization, that's why it's done in a separate pass.
# Make listnode be the LIST or CONST element.
listnode = child[1] if nt == '+' else node
# left is the leftmost element in the addition.
# left = None means the first element of the list must be
# turned into a cast within the loop.
left = child[0] if nt == '+' else None
if listnode.SEF:
for elem in (listnode.value if listnode.nt == 'CONST'
else listnode.ch):
elemnode = nr(nt='CONST',
t=lslcommon.PythonType2LSL[type(elem)],
value=elem, SEF=True
) if listnode.nt == 'CONST' else elem
left = (self.Cast(elemnode, 'list') if left is None
else nr(nt='+', t='list', SEF=True,
ch=[left, elemnode]))
del elemnode
if left is not None: # it's none for empty lists
parent[index] = left
# Do another pass on the result
self.RecursiveLastPass(parent, index)
return
del listnode, left
if nt == 'FNDEF':
# StChAreBad will be True if this is a user-defined function,
# where state changes are considered bad.
# BadStCh will be True if at least one state change statement
# is found while monitoring state changes.
self.subinfo['StChAreBad'] = hasattr(node, 'scope')
self.BadStCh = False
return
if nt == 'IF':
if len(child) == 2:
# Don't monitor the children.
self.subinfo['StChAreBad'] = False
return
if nt == 'DO':
self.subinfo['StChAreBad'] = False
return
if nt == 'FOR':
self.subinfo['StChAreBad'] = False
return
if nt == 'WHILE':
self.subinfo['StChAreBad'] = False
return
if nt == 'STSW':
if self.subinfo['StChAreBad']:
# Found one.
self.BadStCh = True
return
if nt == 'FNCALL':
# lslrenamer can benefit from a list of used library functions,
# so provide it.
if 'Loc' not in self.symtab[0][node.name]:
# system library function
self.usedlibfuncs.add(node.name)
if nt == 'JUMP':
if self.lastLabels:
# This jump is labeled. The jumps that go to any of its labels
# might be changeable to the destination of this jump, if the
# scope of the destination is visible from those jumps, and the
# jump eliminated.
# TODO: We need the positions of these jumps for this to work.
# We could perhaps change 'ref' in the symbol to a list instead
# of a counter, pointing to the jumps.
pass
if nt == '@':
self.curLabels.add(node)
if self.lastStmt.node.nt == 'JUMP':
jump = self.lastStmt.node
if jump.scope == node.scope and jump.name == node.name:
# Remove the jump
self.lastStmt.parent[self.lastStmt.index] = nr(nt=';')
assert self.symtab[node.scope][node.name]['ref'] > 0
self.symtab[node.scope][node.name]['ref'] -= 1
if nt == '{}':
self.scopeStack.append(node.scope)
def LastPassPostOrder(self, parent, index):
node = parent[index]
nt = node.nt
child = node.ch
if nt == 'FNDEF':
if hasattr(node, 'scope') and self.BadStCh:
# There is at least one bad state change statement in the
# function (must be the result of optimization).
# Insert dummy IF(1){...} statement covering the whole function
# (if it returs a value, insert a return statement too).
child[0] = nr(nt='{}', t=None, scope=len(self.symtab), ch=[
nr(nt='IF', t=None, ch=[
nr(nt='CONST', t='integer', value=1, SEF=True),
child[0]
])
])
self.symtab.append({})
child = node.ch
if node.t is not None:
# Inserting a state switch in a function that returns a
# value must count as one of the dumbest things to do.
# We do as best as we can: add a return statement with the
# default value for the type.
child[0].ch.append(nr(nt='RETURN', t=None, ch=[
nr(nt='CONST', t=node.t, SEF=True,
value=lslcommon.LSLTypeDefaults[node.t]
)]
))
del self.BadStCh
return
if nt == 'EXPR':
self.inExpr = False
if nt == '{}':
self.scopeStack.pop()
if nt == 'WHILE' or nt == 'DO' or nt == 'FOR':
self.prevStmt = self.lastStmt
self.lastStmt = rec(node=node, parent=parent, index=index)
def RecursiveLastPass(self, parent, index):
subinfo = self.subinfo
self.subinfo = subinfo.copy()
self.LastPassPreOrder(parent, index)
if parent[index].ch is not None:
child = parent[index].ch
idx = 0
while idx < len(child):
self.RecursiveLastPass(child, idx)
idx += 1
self.LastPassPostOrder(parent, index)
self.subinfo = subinfo
def LastPass(self):
"""Last optimizations pass"""
self.globalmode = False
tree = self.tree
self.usedlibfuncs = set()
self.scopeStack = [0]
self.curLabels = set()
self.lastLabels = set()
self.prevStmt = None
self.lastStmt = None
self.inExpr = False
# self.subinfo is subtree-local info.
self.subinfo = {}
for idx in xrange(len(tree)):
if tree[idx].nt == 'DECL':
self.globalmode = True
self.RecursiveLastPass(tree, idx)
self.globalmode = False
else:
self.RecursiveLastPass(tree, idx)
assert len(self.scopeStack) == 1 and self.scopeStack[0] == 0
return {'libfuncs':self.usedlibfuncs}