transforms.interleaver: inline calls.

This commit is contained in:
whitequark 2015-11-24 00:02:07 +08:00
parent 2a82eb7219
commit 178ff74da2
1 changed files with 50 additions and 45 deletions

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@ -5,6 +5,7 @@ the timestamp would always monotonically nondecrease.
from .. import types, builtins, ir, iodelay
from ..analyses import domination
from ..algorithms import inline
def delay_free_subgraph(root, limit):
visited = set()
@ -25,9 +26,24 @@ def delay_free_subgraph(root, limit):
return True
def iodelay_of_block(block):
terminator = block.terminator()
if isinstance(terminator, ir.Delay):
# We should be able to fold everything without free variables.
folded_expr = terminator.expr.fold()
assert iodelay.is_const(folded_expr)
return folded_expr.value
else:
return 0
def is_pure_delay(insn):
return isinstance(insn, ir.Builtin) and insn.op in ("delay", "delay_mu")
def is_impure_delay_block(block):
terminator = block.terminator()
return isinstance(terminator, ir.Delay) and \
not is_pure_delay(terminator.decomposition())
class Interleaver:
def __init__(self, engine):
self.engine = engine
@ -64,25 +80,24 @@ class Interleaver:
source_times = [0 for _ in source_blocks]
while len(source_blocks) > 0:
def iodelay_of_block(block):
terminator = block.terminator()
if isinstance(terminator, ir.Delay):
# We should be able to fold everything without free variables.
folded_expr = terminator.expr.fold()
assert iodelay.is_const(folded_expr)
return folded_expr.value
else:
return 0
def time_after_block(pair):
index, block = pair
return source_times[index] + iodelay_of_block(block)
index, source_block = min(enumerate(source_blocks), key=time_after_block)
# Always prefer impure blocks (with calls) to pure blocks, because
# impure blocks may expand with smaller delays appearing, and in
# case of a tie, if a pure block is preferred, this would violate
# the timeline monotonicity.
available_source_blocks = list(filter(is_impure_delay_block, source_blocks))
if not any(available_source_blocks):
available_source_blocks = source_blocks
index, source_block = min(enumerate(available_source_blocks), key=time_after_block)
source_block_delay = iodelay_of_block(source_block)
new_target_time = source_times[index] + source_block_delay
target_time_delta = new_target_time - target_time
assert target_time_delta >= 0
target_terminator = target_block.terminator()
if isinstance(target_terminator, ir.Parallel):
@ -93,42 +108,32 @@ class Interleaver:
source_terminator = source_block.terminator()
if isinstance(source_terminator, ir.Delay):
old_decomp = source_terminator.decomposition()
if not isinstance(source_terminator, ir.Delay):
source_terminator.replace_with(ir.Branch(source_terminator.target()))
else:
old_decomp = None
if target_time_delta > 0:
assert isinstance(source_terminator, ir.Delay)
old_decomp = source_terminator.decomposition()
if is_pure_delay(old_decomp):
if target_time_delta > 0:
new_decomp_expr = ir.Constant(int(target_time_delta), builtins.TInt64())
new_decomp = ir.Builtin("delay_mu", [new_decomp_expr], builtins.TNone())
new_decomp.loc = old_decomp.loc
source_terminator.basic_block.insert(source_terminator, new_decomp)
else: # It's a call.
need_to_inline = False
for other_source_block in filter(lambda block: block != source_block,
source_blocks):
other_source_terminator = other_source_block.terminator()
if not (is_pure_delay(other_source_terminator.decomposition()) and \
iodelay.is_const(other_source_terminator.expr) and \
other_source_terminator.expr.fold().value >= source_block_delay):
need_to_inline = True
break
if need_to_inline:
assert False
else:
old_decomp, new_decomp = None, old_decomp
source_terminator.replace_with(ir.Delay(iodelay.Const(target_time_delta), {},
new_decomp, source_terminator.target()))
source_terminator.basic_block.insert(new_decomp, before=source_terminator)
source_terminator.expr = iodelay.Const(target_time_delta)
source_terminator.set_decomposition(new_decomp)
else:
source_terminator.replace_with(ir.Branch(source_terminator.target()))
if old_decomp is not None:
old_decomp.erase()
else: # It's a call.
need_to_inline = len(source_blocks) > 1
if need_to_inline:
inline(old_decomp)
postdom_tree = domination.PostDominatorTree(func)
continue
elif target_time_delta > 0:
source_terminator.expr = iodelay.Const(target_time_delta)
else:
source_terminator.replace_with(ir.Branch(source_terminator.target()))
target_block = source_block
target_time = new_target_time