def split_blocks_at_errors(blocks: List[BasicBlock],
default_error_handler: BasicBlock,
func: str) -> List[BasicBlock]:
new_blocks = [] # type: List[BasicBlock]
# First split blocks on ops that may raise.
for block in blocks:
ops = block.ops
block.ops = []
cur_block = block
new_blocks.append(cur_block)
# If the block has an error handler specified, use it. Otherwise
# fall back to the default.
error_label = block.error_handler or default_error_handler
block.error_handler = None
for op in ops:
cur_block.ops.append(op)
if isinstance(op, RegisterOp) and op.error_kind != ERR_NEVER:
# Split
new_block = BasicBlock()
new_blocks.append(new_block)
if op.error_kind == ERR_MAGIC:
# Op returns an error value on error that depends on result RType.
variant = Branch.IS_ERROR
negated = False
elif op.error_kind == ERR_FALSE:
# Op returns a C false value on error.
variant = Branch.BOOL_EXPR
negated = True
else:
assert False, 'unknown error kind %d' % op.error_kind
# Void ops can't generate errors since error is always
# indicated by a special value stored in a register.
assert not op.is_void, "void op generating errors?"
branch = Branch(op,
true_label=error_label,
false_label=new_block,
op=variant,
line=op.line)
branch.negated = negated
if op.line != NO_TRACEBACK_LINE_NO:
branch.traceback_entry = (func, op.line)
cur_block.ops.append(branch)
cur_block = new_block
return new_blocks
def split_blocks_at_errors(blocks: List[BasicBlock],
default_error_handler: BasicBlock,
func: str) -> List[BasicBlock]:
new_blocks = [] # type: List[BasicBlock]
mapping = {}
partial_ops = set()
# First split blocks on ops that may raise.
for block in blocks:
ops = block.ops
i0 = 0
i = 0
next_block = BasicBlock()
while i < len(ops) - 1:
op = ops[i]
if isinstance(op, RegisterOp) and op.error_kind != ERR_NEVER:
# Split
new_blocks.append(next_block)
new_block = next_block
next_block = BasicBlock()
new_block.ops.extend(ops[i0:i + 1])
if op.error_kind == ERR_MAGIC:
# Op returns an error value on error that depends on result RType.
variant = Branch.IS_ERROR
negated = False
elif op.error_kind == ERR_FALSE:
# Op returns a C false value on error.
variant = Branch.BOOL_EXPR
negated = True
else:
assert False, 'unknown error kind %d' % op.error_kind
# Void ops can't generate errors since error is always
# indicated by a special value stored in a register.
assert not op.is_void, "void op generating errors?"
# If the block has an error handler specified, use it. Otherwise
# fall back to the default.
error_label = block.error_handler or default_error_handler
branch = Branch(op,
true_label=error_label,
false_label=next_block,
op=variant,
line=op.line)
branch.negated = negated
if op.line != NO_TRACEBACK_LINE_NO:
branch.traceback_entry = (func, op.line)
partial_ops.add(branch) # Only tweak true label of these
new_block.ops.append(branch)
if i0 == 0:
mapping[block] = new_block
i += 1
i0 = i
else:
i += 1
new_blocks.append(next_block)
next_block.ops.extend(ops[i0:i + 1])
if i0 == 0:
mapping[block] = next_block
# Adjust all labels to reflect the new blocks.
for block in new_blocks:
for op in block.ops:
if isinstance(op, Goto):
op.label = mapping[op.label]
elif isinstance(op, Branch):
if op not in partial_ops:
op.false = mapping[op.false]
op.true = mapping[op.true]
return new_blocks
