mirror of
https://github.com/Sei-Lisa/LSL-PyOptimizer
synced 2025-07-01 15:48:21 +00:00
399 lines
16 KiB
Python
399 lines
16 KiB
Python
|
|
import lslfuncs
|
|
from lslparse import warning
|
|
|
|
class optimizer(object):
|
|
|
|
# Default values per type when declaring variables
|
|
DefaultValues = {'integer': 0, 'float': 0.0, 'string': u'',
|
|
'key': lslfuncs.Key(u''), 'vector': lslfuncs.ZERO_VECTOR,
|
|
'rotation': lslfuncs.ZERO_ROTATION, 'list': []
|
|
}
|
|
|
|
# explicitly exclude assignments
|
|
binary_ops = frozenset(('+','-','*','/','%','<<','>>','<','<=','>','>=',
|
|
'==','!=','|','^','&','||','&&'))
|
|
assign_ops = frozenset(('=','+=','-=','*=','/=','%=','&=','|=','^=','<<=','>>='))
|
|
LSL2PythonType = {'integer':int, 'float':float, 'string':unicode, 'key':lslfuncs.Key,
|
|
'vector':lslfuncs.Vector, 'rotation':lslfuncs.Quaternion, 'list':list}
|
|
|
|
ignored_stmts = frozenset(('V++','V--','--V','++V',';','STSW','JUMP','@'))
|
|
|
|
def FoldAndRemoveEmptyStmts(self, lst):
|
|
"""Utility function for elimination of useless expressions in FOR"""
|
|
idx = 0
|
|
while idx < len(lst):
|
|
self.FoldTree(lst, idx)
|
|
self.FoldStmt(lst, idx)
|
|
# If eliminated, it must be totally removed. A ';' won't do.
|
|
if lst[idx]['nt'] == ';':
|
|
del lst[idx]
|
|
else:
|
|
idx += 1
|
|
|
|
def FoldStmt(self, parent, index):
|
|
"""If the statement is a constant or an identifier, remove it as it does
|
|
nothing.
|
|
"""
|
|
# Ideally this should consider side effect analysis of the whole thing.
|
|
if parent[index]['nt'] in ('CONST', 'IDENT', 'FIELD'):
|
|
parent[index] = {'nt':';','t':None}
|
|
|
|
def FoldTree(self, parent, index):
|
|
"""Recursively traverse the tree to fold constants, changing it in
|
|
place.
|
|
|
|
Also optimizes away IF, WHILE, etc.
|
|
"""
|
|
node = parent[index]
|
|
if node is None: return # Deleted statement
|
|
nt = node['nt']
|
|
child = node['ch'] if 'ch' in node else None
|
|
|
|
if nt == 'CONST':
|
|
# Job already done
|
|
return
|
|
|
|
if nt == 'CAST':
|
|
self.FoldTree(child, 0)
|
|
if child[0]['nt'] == 'CONST':
|
|
# Enable key constants. We'll typecast them back on output, but
|
|
# this enables some optimizations.
|
|
#if node['t'] != 'key': # key constants not possible
|
|
|
|
parent[index] = {'nt':'CONST', 't':node['t'],
|
|
'value':lslfuncs.typecast(
|
|
child[0]['value'], self.LSL2PythonType[node['t']])}
|
|
return
|
|
|
|
if nt == 'NEG':
|
|
self.FoldTree(child, 0)
|
|
if child[0]['nt'] == 'CONST':
|
|
node = parent[index] = child[0]
|
|
node['value'] = lslfuncs.neg(node['value'])
|
|
return
|
|
|
|
if nt == '!':
|
|
self.FoldTree(child, 0)
|
|
if child[0]['nt'] == 'CONST':
|
|
node = parent[index] = child[0]
|
|
node['value'] = int(not node['value'])
|
|
return
|
|
|
|
if nt == '~':
|
|
self.FoldTree(child, 0)
|
|
if child[0]['nt'] == 'CONST':
|
|
node = parent[index] = child[0]
|
|
node['value'] = ~node['value']
|
|
return
|
|
|
|
if nt == '()':
|
|
self.FoldTree(child, 0)
|
|
if child[0]['nt'] in ('CONST', 'VECTOR', 'ROTATION', 'LIST',
|
|
'IDENT', 'FIELD', 'V++', 'V--', 'FUNCTION', 'PRINT'):
|
|
# Child is an unary postfix expression; parentheses are
|
|
# redundant and can be removed safely. Not strictly an
|
|
# optimization but it helps keep the output tidy-ish a bit.
|
|
# It's not done in general (e.g. (a * b) + c does not need
|
|
# parentheses but these are not eliminated). Only the cases
|
|
# like (myvar) are simplified.
|
|
parent[index] = child[0]
|
|
return
|
|
|
|
if nt in self.binary_ops:
|
|
# RTL evaluation
|
|
self.FoldTree(child, 1)
|
|
self.FoldTree(child, 0)
|
|
if child[0]['nt'] == child[1]['nt'] == 'CONST':
|
|
op1 = child[0]['value']
|
|
op2 = child[1]['value']
|
|
if nt == '+':
|
|
result = lslfuncs.add(op1, op2)
|
|
elif nt == '-':
|
|
result = lslfuncs.sub(op1, op2)
|
|
elif nt == '*':
|
|
result = lslfuncs.mul(op1, op2)
|
|
elif nt == '/':
|
|
result = lslfuncs.div(op1, op2)
|
|
elif nt == '%':
|
|
result = lslfuncs.mod(op1, op2)
|
|
elif nt == '<<':
|
|
result = lslfuncs.S32(op1 << (op2 & 31))
|
|
elif nt == '>>':
|
|
result = lslfuncs.S32(op1 >> (op2 & 31))
|
|
elif nt == '==' or nt == '!=':
|
|
result = lslfuncs.compare(op1, op2, Eq = (nt == '=='))
|
|
elif nt in ('<', '<=', '>', '>='):
|
|
if nt in ('>', '<='):
|
|
result = lslfuncs.less(op2, op1)
|
|
else:
|
|
result = lslfuncs.less(op1, op2)
|
|
if nt in ('>=', '<='):
|
|
result = 1-result
|
|
elif nt == '|':
|
|
result = op1 | op2
|
|
elif nt == '^':
|
|
result = op1 ^ op2
|
|
elif nt == '&':
|
|
result = op1 & op2
|
|
elif nt == '||':
|
|
result = int(op1 or op2)
|
|
elif nt == '&&':
|
|
result = int(op1 and op2)
|
|
else:
|
|
raise Exception(u'Internal error: Operator not found: ' + nt.decode('utf8')) # pragma: no cover
|
|
parent[index] = {'nt':'CONST', 't':node['t'], 'value':result}
|
|
elif nt == '-' and child[0]['t'] in ('integer', 'float') \
|
|
and child[1]['t'] in ('integer', 'float'):
|
|
# Change - to + - for int/float
|
|
if child[1]['nt'] == 'CONST':
|
|
if child[1]['value'] == 0:
|
|
parent[index] = child[0]
|
|
else:
|
|
node['nt'] = '+'
|
|
child[1]['value'] = lslfuncs.neg(child[1]['value'])
|
|
#TODO: Implement to transform 0-x into -x: elif child[0]['nt'] == 'CONST':
|
|
else:
|
|
node['nt'] = '+'
|
|
child[1] = {'nt':'NEG', 't':child[1]['t'], 'ch':[child[1]]}
|
|
elif nt == '<<' and child[1]['nt'] == 'CONST':
|
|
# Transforming << into multiply saves some bytes.
|
|
if child[1]['value'] & 31:
|
|
# x << 3 --> x * 8
|
|
# Do we need parentheses for *? It depends on x
|
|
# e.g. x+3<<3 needs parentheses when converted to (x+3)*8
|
|
if child[0]['nt'] in ('+', '-', 'NEG'): # operands with priority between * and << #TODO: CHECK
|
|
child[0] = {'nt':'()', 't':child[0]['t'], 'ch':[child[0]]}
|
|
# we have {<<, something, {CONST n}}, transform into {*, something, {CONST n}}
|
|
node['nt'] = '*'
|
|
child[1]['value'] = 1<<(child[1]['value'] & 31)
|
|
else: # x << 0 --> x
|
|
parent[index] = child[0]
|
|
else:
|
|
pass # TODO: Eliminate redundancy (x+0, x*1, x*-1, v+ZERO_VECTOR, perhaps x-1=~-x, etc.)
|
|
# Include != to ^ and || to | and maybe && to &
|
|
# Note some cases e.g. x*0 can't be optimized away without side-effect analysis.
|
|
# But some cases like %1 can be turned into *0 to save bytes.
|
|
# Turn also % (power of 2) into & mask (oops, nope, negative doesn't work)
|
|
# Maybe turn != -1 into ~ in if()'s.
|
|
return
|
|
|
|
if nt in self.assign_ops:
|
|
# TODO: Eliminate redundant operations, e.g. a += 0; etc.
|
|
# Consider also e.g. x -= 1 or x -= a transforming it into +=.
|
|
# Actually just consider transforming the whole thing into a
|
|
# regular assignment, as there are no gains and it simplifies the
|
|
# optimization.
|
|
self.FoldTree(child, 1)
|
|
return
|
|
|
|
if nt == 'IDENT' or nt == 'FLD':
|
|
if self.globalmode:
|
|
ident = child[0] if nt == 'FLD' else node
|
|
# Resolve constant values so they can be optimized
|
|
sym = self.symtab[ident['scope']][ident['name']]
|
|
|
|
defn = self.tree[sym['Loc']]
|
|
assert defn['name'] == ident['name']
|
|
|
|
# Assume we already were there
|
|
if 'ch' in defn:
|
|
val = defn['ch'][0]
|
|
if val['nt'] != 'CONST' or ident['t'] in ('list', 'key'):
|
|
return
|
|
else:
|
|
val = {'nt':'CONST', 't':defn['t'],
|
|
'value':self.DefaultValues[defn['t']]}
|
|
if nt == 'FLD':
|
|
val = {'nt':'CONST', 't':'float',
|
|
'value':val['value']['xyzs'.index(node['fld'])]}
|
|
parent[index] = val
|
|
return
|
|
|
|
if nt == 'FNCALL':
|
|
for idx in xrange(len(child)-1, -1, -1):
|
|
self.FoldTree(child, idx)
|
|
if 'fn' in self.symtab[0][node['name']]:
|
|
fn = self.symtab[0][node['name']]['fn']
|
|
if all(arg['nt'] == 'CONST' for arg in child):
|
|
# Call it
|
|
value = fn(*tuple(arg['value'] for arg in child))
|
|
if not self.foldtabs and isinstance(value, unicode) and '\t' in value:
|
|
warning('WARNING: Tab in function result and foldtabs option not used.')
|
|
return
|
|
parent[index] = {'nt':'CONST', 't':node['t'], 'value':value}
|
|
return
|
|
|
|
if nt == 'PRINT':
|
|
# useless but who knows
|
|
self.FoldTree(child, 0)
|
|
return
|
|
|
|
if nt in ('VECTOR', 'ROTATION', 'LIST'):
|
|
isconst = True
|
|
for idx in xrange(len(child)-1, -1, -1):
|
|
self.FoldTree(child, idx)
|
|
if child[idx]['nt'] != 'CONST':
|
|
isconst = False
|
|
if isconst:
|
|
value = [elem['value'] for elem in child]
|
|
if nt == 'VECTOR':
|
|
value = lslfuncs.Vector([lslfuncs.ff(x) for x in value])
|
|
elif nt == 'ROTATION':
|
|
value = lslfuncs.Quaternion([lslfuncs.ff(x) for x in value])
|
|
parent[index] = {'nt':'CONST', 't':node['t'], 'value':value}
|
|
return
|
|
|
|
if nt in ('{}', 'FNDEF', 'STDEF'):
|
|
for idx in xrange(len(child)):
|
|
self.FoldTree(child, idx)
|
|
self.FoldStmt(child, idx)
|
|
return
|
|
|
|
if nt == 'IF':
|
|
self.FoldTree(child, 0)
|
|
if child[0]['nt'] == 'CONST':
|
|
# We can remove one of the branches safely.
|
|
if lslfuncs.cond(child[0]['value']):
|
|
self.FoldTree(child, 1)
|
|
parent[index] = child[1]
|
|
self.FoldStmt(child, 1)
|
|
elif len(child) > 2:
|
|
self.FoldTree(child, 2)
|
|
parent[index] = child[2]
|
|
self.FoldStmt(child, 2)
|
|
else:
|
|
# No ELSE branch, replace the statement with an empty one.
|
|
parent[index] = {'nt':';', 't':None}
|
|
else:
|
|
self.FoldTree(child, 1)
|
|
self.FoldStmt(child, 1)
|
|
if len(child) > 2:
|
|
self.FoldTree(child, 2)
|
|
self.FoldStmt(child, 2)
|
|
return
|
|
|
|
if nt == 'WHILE':
|
|
self.FoldTree(child, 0)
|
|
if child[0]['nt'] == 'CONST':
|
|
# See if the whole WHILE can be eliminated.
|
|
if lslfuncs.cond(child[0]['value']):
|
|
# Endless loop which must be kept.
|
|
# First, replace the constant.
|
|
child[0].update({'t':'integer', 'value':1})
|
|
# Recurse on the statement.
|
|
self.FoldTree(child, 1)
|
|
self.FoldStmt(child, 1)
|
|
else:
|
|
# Can be removed.
|
|
parent[index] = {'nt':';', 't':None}
|
|
else:
|
|
self.FoldTree(child, 1)
|
|
self.FoldStmt(child, 1)
|
|
return
|
|
|
|
if nt == 'DO':
|
|
self.FoldTree(child, 0) # This one is always executed.
|
|
self.FoldStmt(child, 0)
|
|
self.FoldTree(child, 1)
|
|
# See if the latest part is a constant.
|
|
if child[1]['nt'] == 'CONST':
|
|
if lslfuncs.cond(child[1]['value']):
|
|
# Endless loop. Replace the constant.
|
|
child[1].update({'t':'integer', 'value':1})
|
|
else:
|
|
# Only one go. Replace with the statement(s).
|
|
parent[index] = child[0]
|
|
return
|
|
|
|
if nt == 'FOR':
|
|
assert child[0]['nt'] == 'EXPRLIST'
|
|
assert child[2]['nt'] == 'EXPRLIST'
|
|
self.FoldAndRemoveEmptyStmts(child[0]['ch'])
|
|
|
|
self.FoldTree(child, 1) # Condition.
|
|
if child[1]['nt'] == 'CONST':
|
|
# FOR is delicate. It can have multiple expressions at start.
|
|
# And if there is more than one, these expressions will need a
|
|
# new block, which means new scope, which is dangerous.
|
|
# They are expressions, no declarations or labels allowed, but
|
|
# it feels creepy.
|
|
if lslfuncs.cond(child[1]['value']):
|
|
# Endless loop. Just replace the constant and traverse the rest.
|
|
child[1].update({'t':'integer', 'value':1})
|
|
self.FoldAndRemoveEmptyStmts(child[2]['ch'])
|
|
self.FoldTree(child, 3)
|
|
self.FoldStmt(child, 3)
|
|
elif len(child[0]['ch']) > 1:
|
|
parent[index] = {'nt':'{}', 't':None, 'ch':child[0]['ch']}
|
|
elif child[0]['ch']:
|
|
parent[index] = child[0]['ch'][0]
|
|
else:
|
|
parent[index] = {'nt':';', 't':None}
|
|
else:
|
|
self.FoldAndRemoveEmptyStmts(child[2]['ch'])
|
|
self.FoldTree(child, 3)
|
|
self.FoldStmt(child, 3)
|
|
return
|
|
|
|
if nt == 'RETURN':
|
|
if child:
|
|
self.FoldTree(child, 0)
|
|
return
|
|
|
|
if nt == 'DECL':
|
|
# The expression code is elsewhere.
|
|
if child:
|
|
self.FoldTree(child, 0)
|
|
# TODO: Remove assignment if integer zero.
|
|
else:
|
|
# TODO: Add assignment if vector, rotation or float.
|
|
pass
|
|
return
|
|
|
|
if nt in self.ignored_stmts:
|
|
return
|
|
|
|
assert False, 'Internal error: This should not happen, node type = ' + nt # pragma: no cover
|
|
|
|
def IsValidGlobalConstant(self, decl):
|
|
if 'ch' not in decl:
|
|
return True
|
|
expr = decl['ch'][0]
|
|
if expr['nt'] in ('CONST', 'IDENT'):
|
|
return True
|
|
if expr['nt'] not in ('VECTOR', 'ROTATION', 'LIST'):
|
|
return False
|
|
return all(elem['nt'] in ('CONST', 'IDENT') for elem in expr['ch'])
|
|
|
|
def optimize(self, treesymtab, options = ('optimize',)):
|
|
"""Optimize the symbolic table symtab in place. Requires a table of
|
|
predefined functions for folding constants.
|
|
"""
|
|
|
|
if 'optimize' not in options:
|
|
return
|
|
|
|
self.foldtabs = 'foldtabs' in options
|
|
|
|
# TODO: Add option to handle local jumps properly.
|
|
|
|
tree, symtab = self.tree, self.symtab = treesymtab
|
|
|
|
self.globalmode = False
|
|
|
|
# Constant folding pass. It does some other optimizations along the way.
|
|
for idx in xrange(len(tree)):
|
|
if tree[idx]['nt'] == 'DECL':
|
|
self.globalmode = True
|
|
self.FoldTree(tree, idx)
|
|
self.globalmode = False
|
|
if not self.IsValidGlobalConstant(tree[idx]):
|
|
warning('WARNING: Expression does not collapse to a single constant.')
|
|
else:
|
|
self.FoldTree(tree, idx)
|
|
|
|
treesymtab = (self.tree, self.symtab)
|
|
del self.tree
|
|
del self.symtab
|
|
return treesymtab
|