1berry/cpython
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

gh-104909: Implement conditional stack effects for macros (#105748)

Browse Source
This commit is contained in:
Guido van Rossum 2023-06-14 13:50:48 -07:00 committed by GitHub
parent 820febc535
commit 4caa728b2c
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 80 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

53
Tools/cases_generator/generate_cases.py
View File

@ -179,14 +179,12 @@ class Formatter:
def stack_adjust(
self,
diff: int,
input_effects: list[StackEffect],
output_effects: list[StackEffect],
):
# TODO: Get rid of 'diff' parameter
shrink, isym = list_effect_size(input_effects)
grow, osym = list_effect_size(output_effects)
diff += grow - shrink
diff = grow - shrink
if isym and isym != osym:
self.emit(f"STACK_SHRINK({isym});")
if diff < 0:
@ -355,7 +353,6 @@ class Instruction:
# Write net stack growth/shrinkage
out.stack_adjust(
0,
[ieff for ieff in self.input_effects],
[oeff for oeff in self.output_effects],
)
@ -848,9 +845,14 @@ class Analyzer:
Ignore cache effects.
Return the list of variable names and the initial stack pointer.
Return the list of variables (as StackEffects) and the initial stack pointer.
"""
lowest = current = highest = 0
conditions: dict[int, str] = {} # Indexed by 'current'.
last_instr: Instruction | None = None
for thing in components:
if isinstance(thing, Instruction):
last_instr = thing
for thing in components:
match thing:
case Instruction() as instr:
@ -863,9 +865,24 @@ class Analyzer:
"which are not supported in macro instructions",
instr.inst, # TODO: Pass name+location of macro
)
if any(eff.cond for eff in instr.input_effects):
self.error(
f"Instruction {instr.name!r} has conditional input stack effect, "
"which are not supported in macro instructions",
instr.inst, # TODO: Pass name+location of macro
)
if any(eff.cond for eff in instr.output_effects) and instr is not last_instr:
self.error(
f"Instruction {instr.name!r} has conditional output stack effect, "
"but is not the last instruction in a macro",
instr.inst, # TODO: Pass name+location of macro
)
current -= len(instr.input_effects)
lowest = min(lowest, current)
current += len(instr.output_effects)
for eff in instr.output_effects:
if eff.cond:
conditions[current] = eff.cond
current += 1
highest = max(highest, current)
case parser.CacheEffect():
pass
@ -874,9 +891,9 @@ class Analyzer:
# At this point, 'current' is the net stack effect,
# and 'lowest' and 'highest' are the extremes.
# Note that 'lowest' may be negative.
# TODO: Reverse the numbering.
stack = [
StackEffect(f"_tmp_{i+1}", "") for i in reversed(range(highest - lowest))
StackEffect(f"_tmp_{i}", "", conditions.get(highest - i, ""))
for i in reversed(range(1, highest - lowest + 1))
]
return stack, -lowest
@ -908,6 +925,7 @@ class Analyzer:
low = 0
sp = 0
high = 0
pushed_symbolic: list[str] = []
for comp in parts:
for effect in comp.instr.input_effects:
assert not effect.cond, effect
@ -915,8 +933,9 @@ class Analyzer:
sp -= 1
low = min(low, sp)
for effect in comp.instr.output_effects:
assert not effect.cond, effect
assert not effect.size, effect
if effect.cond:
pushed_symbolic.append(maybe_parenthesize(f"{maybe_parenthesize(effect.cond)} ? 1 : 0"))
sp += 1
high = max(sp, high)
if high != max(0, sp):
@ -926,7 +945,8 @@ class Analyzer:
# calculations to use the micro ops.
self.error("Macro has virtual stack growth", thing)
popped = str(-low)
pushed = str(sp - low)
pushed_symbolic.append(str(sp - low - len(pushed_symbolic)))
pushed = " + ".join(pushed_symbolic)
case parser.Pseudo():
instr = self.pseudo_instrs[thing.name]
popped = pushed = None
@ -1203,7 +1223,15 @@ class Analyzer:
with self.out.block(f"TARGET({mac.name})"):
if mac.predicted:
self.out.emit(f"PREDICTED({mac.name});")
for i, var in reversed(list(enumerate(mac.stack))):
# The input effects should have no conditionals.
# Only the output effects do (for now).
ieffects = [
StackEffect(eff.name, eff.type) if eff.cond else eff
for eff in mac.stack
]
for i, var in reversed(list(enumerate(ieffects))):
src = None
if i < mac.initial_sp:
src = StackEffect(f"stack_pointer[-{mac.initial_sp - i}]", "")
@ -1211,8 +1239,7 @@ class Analyzer:
yield
# TODO: Use slices of mac.stack instead of numeric values
self.out.stack_adjust(mac.final_sp - mac.initial_sp, [], [])
self.out.stack_adjust(ieffects[:mac.initial_sp], mac.stack[:mac.final_sp])
for i, var in enumerate(reversed(mac.stack[: mac.final_sp]), 1):
dst = StackEffect(f"stack_pointer[-{i}]", "")

40
Tools/cases_generator/test_generator.py
View File

@ -432,3 +432,43 @@ def test_cond_effect():
}
"""
run_cases_test(input, output)
def test_macro_cond_effect():
input = """
op(A, (left, middle, right --)) {
# Body of A
}
op(B, (-- deep, extra if (oparg), res)) {
# Body of B
}
macro(M) = A + B;
"""
output = """
TARGET(M) {
PyObject *_tmp_1 = stack_pointer[-1];
PyObject *_tmp_2 = stack_pointer[-2];
PyObject *_tmp_3 = stack_pointer[-3];
{
PyObject *right = _tmp_1;
PyObject *middle = _tmp_2;
PyObject *left = _tmp_3;
# Body of A
}
{
PyObject *deep;
PyObject *extra = NULL;
PyObject *res;
# Body of B
_tmp_3 = deep;
if (oparg) { _tmp_2 = extra; }
_tmp_1 = res;
}
STACK_SHRINK(1);
STACK_GROW((oparg ? 1 : 0));
stack_pointer[-1] = _tmp_1;
if (oparg) { stack_pointer[-2] = _tmp_2; }
stack_pointer[-3] = _tmp_3;
DISPATCH();
}
"""
run_cases_test(input, output)