Mercurial > lcfOS
annotate python/transform.py @ 296:9417caea2eb3
Directorized some backend files
author | Windel Bouwman |
---|---|
date | Sun, 01 Dec 2013 13:36:58 +0100 |
parents | 02385f62f250 |
children |
rev | line source |
---|---|
240 | 1 """ |
2 Transformation to optimize IR-code | |
3 """ | |
4 | |
253 | 5 import logging |
279 | 6 import ir |
173 | 7 # Standard passes: |
8 | |
9 class FunctionPass: | |
255 | 10 def __init__(self): |
11 self.logger = logging.getLogger('optimize') | |
12 | |
253 | 13 def run(self, ir): |
14 """ Main entry point for the pass """ | |
255 | 15 self.logger.info('Running pass {}'.format(type(self))) |
16 ir.check() | |
253 | 17 self.prepare() |
18 for f in ir.Functions: | |
19 self.onFunction(f) | |
255 | 20 ir.check() |
253 | 21 |
22 def onFunction(self, f): | |
23 """ Override this virtual method """ | |
24 raise NotImplementedError() | |
25 | |
26 def prepare(self): | |
27 pass | |
173 | 28 |
240 | 29 |
173 | 30 class BasicBlockPass(FunctionPass): |
240 | 31 def onFunction(self, f): |
274 | 32 for bb in f.Blocks: |
240 | 33 self.onBasicBlock(bb) |
34 | |
35 def onBasicBlock(self, bb): | |
36 """ Override this virtual method """ | |
37 raise NotImplementedError() | |
38 | |
39 | |
173 | 40 class InstructionPass(BasicBlockPass): |
240 | 41 def onBasicBlock(self, bb): |
42 for ins in iter(bb.Instructions): | |
43 self.onInstruction(ins) | |
44 | |
45 def onInstruction(self, ins): | |
46 """ Override this virtual method """ | |
47 raise NotImplementedError() | |
173 | 48 |
280
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
49 |
279 | 50 class BasePass(BasicBlockPass): |
255 | 51 def onBasicBlock(self, bb): |
279 | 52 pass |
53 | |
280
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
54 |
279 | 55 # Usefull transforms: |
56 class ConstantFolder(BasePass): | |
57 def __init__(self): | |
58 super().__init__() | |
59 self.ops = {} | |
60 self.ops['+'] = lambda x, y: x + y | |
61 self.ops['-'] = lambda x, y: x - y | |
62 self.ops['*'] = lambda x, y: x * y | |
63 self.ops['<<'] = lambda x, y: x << y | |
64 | |
65 def postExpr(self, expr): | |
66 if type(i) is BinaryOperator and i.operation in self.ops.keys() and type(i.a) is Const and type(i.b) is Const: | |
280
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
67 vr = self.ops[i.operation](i.a.value, i.b.value) |
279 | 68 return Const(vr) |
69 else: | |
70 return expr | |
237 | 71 |
72 | |
174 | 73 class DeadCodeDeleter(BasicBlockPass): |
252 | 74 def onBasicBlock(self, bb): |
75 def instructionUsed(ins): | |
253 | 76 if not type(ins) in [ImmLoad, BinaryOperator]: |
77 return True | |
252 | 78 if len(ins.defs) == 0: |
79 # In case this instruction does not define any | |
80 # variables, assume it is usefull. | |
81 return True | |
82 return any(d.Used for d in ins.defs) | |
83 | |
84 change = True | |
85 while change: | |
86 change = False | |
87 for i in bb.Instructions: | |
88 if instructionUsed(i): | |
89 continue | |
90 bb.removeInstruction(i) | |
91 change = True | |
173 | 92 |
239 | 93 |
252 | 94 class CommonSubexpressionElimination(BasicBlockPass): |
239 | 95 def onBasicBlock(self, bb): |
96 constMap = {} | |
252 | 97 to_remove = [] |
98 for i in bb.Instructions: | |
99 if isinstance(i, ImmLoad): | |
100 if i.value in constMap: | |
101 t_new = constMap[i.value] | |
102 t_old = i.target | |
253 | 103 logging.debug('Replacing {} with {}'.format(t_old, t_new)) |
261 | 104 t_old.replaceby(t_new) |
252 | 105 to_remove.append(i) |
106 else: | |
107 constMap[i.value] = i.target | |
108 elif isinstance(i, BinaryOperator): | |
109 k = (i.value1, i.operation, i.value2) | |
110 if k in constMap: | |
111 t_old = i.result | |
112 t_new = constMap[k] | |
253 | 113 logging.debug('Replacing {} with {}'.format(t_old, t_new)) |
261 | 114 t_old.replaceby(t_new) |
252 | 115 to_remove.append(i) |
116 else: | |
117 constMap[k] = i.result | |
118 for i in to_remove: | |
253 | 119 logging.debug('removing {}'.format(i)) |
252 | 120 bb.removeInstruction(i) |
240 | 121 |
122 | |
177 | 123 class CleanPass(FunctionPass): |
219 | 124 def onFunction(self, f): |
280
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
125 removeEmptyBasicBlocks(f) |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
126 |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
127 |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
128 def removeEmptyBlocks(f): |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
129 """ Remove empty basic blocks from function. """ |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
130 # If a block only contains a branch, it can be removed: |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
131 empty = lambda b: type(b.FirstInstruction) is ir.Jump |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
132 empty_blocks = list(filter(empty, f.Blocks)) |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
133 for b in empty_blocks: |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
134 # Update predecessors |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
135 preds = b.Predecessors |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
136 if b not in preds + [f.entry]: |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
137 # Do not remove if preceeded by itself |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
138 tgt = b.LastInstruction.target |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
139 for pred in preds: |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
140 pred.LastInstruction.changeTarget(b, tgt) |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
141 logging.debug('Removing empty block: {}'.format(b)) |
02385f62f250
Rework from str interface to Instruction interface
Windel Bouwman
parents:
279
diff
changeset
|
142 f.removeBlock(b) |