def insert_exception_handling(ir: FuncIR) -> None:
# Generate error block if any ops may raise an exception. If an op
# fails without its own error handler, we'll branch to this
# block. The block just returns an error value.
error_label = None
for block in ir.blocks:
can_raise = any(op.can_raise() for op in block.ops)
if can_raise:
error_label = add_handler_block(ir)
break
if error_label:
ir.blocks = split_blocks_at_errors(ir.blocks, error_label, ir.name)
def insert_uninit_checks(ir: FuncIR) -> None:
# Remove dead blocks from the CFG, which helps avoid spurious
# checks due to unused error handling blocks.
cleanup_cfg(ir.blocks)
cfg = get_cfg(ir.blocks)
args = set(reg for reg in ir.env.regs()
if ir.env.indexes[reg] < len(ir.args))
must_defined = analyze_must_defined_regs(ir.blocks, cfg, args,
ir.env.regs())
ir.blocks = split_blocks_at_uninits(ir.env, ir.blocks, must_defined.before)
