gh-119689: generate stack effect metadata for pseudo instructions (#119691)

This commit is contained in:
Irit Katriel 2024-05-29 10:47:56 +01:00 committed by GitHub
parent 7ca74a760a
commit c1e9647107
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
10 changed files with 112 additions and 73 deletions

View File

@ -259,12 +259,16 @@ int _PyOpcode_num_popped(int opcode, int oparg) {
return 1;
case IS_OP:
return 2;
case JUMP:
return 0;
case JUMP_BACKWARD:
return 0;
case JUMP_BACKWARD_NO_INTERRUPT:
return 0;
case JUMP_FORWARD:
return 0;
case JUMP_NO_INTERRUPT:
return 0;
case LIST_APPEND:
return 2 + (oparg-1);
case LIST_EXTEND:
@ -297,6 +301,8 @@ int _PyOpcode_num_popped(int opcode, int oparg) {
return 1;
case LOAD_BUILD_CLASS:
return 0;
case LOAD_CLOSURE:
return 0;
case LOAD_COMMON_CONSTANT:
return 0;
case LOAD_CONST:
@ -347,6 +353,8 @@ int _PyOpcode_num_popped(int opcode, int oparg) {
return 1;
case NOP:
return 0;
case POP_BLOCK:
return 0;
case POP_EXCEPT:
return 1;
case POP_JUMP_IF_FALSE:
@ -385,6 +393,12 @@ int _PyOpcode_num_popped(int opcode, int oparg) {
return 2;
case SETUP_ANNOTATIONS:
return 0;
case SETUP_CLEANUP:
return 0;
case SETUP_FINALLY:
return 0;
case SETUP_WITH:
return 0;
case SET_ADD:
return 2 + (oparg-1);
case SET_FUNCTION_ATTRIBUTE:
@ -405,6 +419,8 @@ int _PyOpcode_num_popped(int opcode, int oparg) {
return 1;
case STORE_FAST_LOAD_FAST:
return 1;
case STORE_FAST_MAYBE_NULL:
return 1;
case STORE_FAST_STORE_FAST:
return 2;
case STORE_GLOBAL:
@ -692,12 +708,16 @@ int _PyOpcode_num_pushed(int opcode, int oparg) {
return 0;
case IS_OP:
return 1;
case JUMP:
return 0;
case JUMP_BACKWARD:
return 0;
case JUMP_BACKWARD_NO_INTERRUPT:
return 0;
case JUMP_FORWARD:
return 0;
case JUMP_NO_INTERRUPT:
return 0;
case LIST_APPEND:
return 1 + (oparg-1);
case LIST_EXTEND:
@ -730,6 +750,8 @@ int _PyOpcode_num_pushed(int opcode, int oparg) {
return 1 + (oparg & 1);
case LOAD_BUILD_CLASS:
return 1;
case LOAD_CLOSURE:
return 1;
case LOAD_COMMON_CONSTANT:
return 1;
case LOAD_CONST:
@ -780,6 +802,8 @@ int _PyOpcode_num_pushed(int opcode, int oparg) {
return 2;
case NOP:
return 0;
case POP_BLOCK:
return 0;
case POP_EXCEPT:
return 0;
case POP_JUMP_IF_FALSE:
@ -818,6 +842,12 @@ int _PyOpcode_num_pushed(int opcode, int oparg) {
return 2;
case SETUP_ANNOTATIONS:
return 0;
case SETUP_CLEANUP:
return 2;
case SETUP_FINALLY:
return 1;
case SETUP_WITH:
return 1;
case SET_ADD:
return 1 + (oparg-1);
case SET_FUNCTION_ATTRIBUTE:
@ -838,6 +868,8 @@ int _PyOpcode_num_pushed(int opcode, int oparg) {
return 0;
case STORE_FAST_LOAD_FAST:
return 1;
case STORE_FAST_MAYBE_NULL:
return 0;
case STORE_FAST_STORE_FAST:
return 0;
case STORE_GLOBAL:

View File

@ -485,7 +485,7 @@ class TestGeneratedCases(unittest.TestCase):
def test_pseudo_instruction_no_flags(self):
input = """
pseudo(OP) = {
pseudo(OP, (in -- out1, out2)) = {
OP1,
};
@ -504,7 +504,7 @@ class TestGeneratedCases(unittest.TestCase):
def test_pseudo_instruction_with_flags(self):
input = """
pseudo(OP, (HAS_ARG, HAS_JUMP)) = {
pseudo(OP, (in1, in2 --), (HAS_ARG, HAS_JUMP)) = {
OP1,
};

View File

@ -0,0 +1 @@
Generate stack effect metadata for pseudo instructions from bytecodes.c.

View File

@ -213,7 +213,7 @@ dummy_func(
}
}
pseudo(LOAD_CLOSURE) = {
pseudo(LOAD_CLOSURE, (-- unused)) = {
LOAD_FAST,
};
@ -259,7 +259,7 @@ dummy_func(
SETLOCAL(oparg, value);
}
pseudo(STORE_FAST_MAYBE_NULL) = {
pseudo(STORE_FAST_MAYBE_NULL, (unused --)) = {
STORE_FAST,
};
@ -2393,12 +2393,12 @@ dummy_func(
#endif /* _Py_TIER2 */
}
pseudo(JUMP) = {
pseudo(JUMP, (--)) = {
JUMP_FORWARD,
JUMP_BACKWARD,
};
pseudo(JUMP_NO_INTERRUPT) = {
pseudo(JUMP_NO_INTERRUPT, (--)) = {
JUMP_FORWARD,
JUMP_BACKWARD_NO_INTERRUPT,
};
@ -2895,19 +2895,27 @@ dummy_func(
ERROR_IF(res == NULL, error);
}
pseudo(SETUP_FINALLY, (HAS_ARG)) = {
pseudo(SETUP_FINALLY, (-- unused), (HAS_ARG)) = {
/* If an exception is raised, restore the stack position
* and push one value before jumping to the handler.
*/
NOP,
};
pseudo(SETUP_CLEANUP, (HAS_ARG)) = {
pseudo(SETUP_CLEANUP, (-- unused, unused), (HAS_ARG)) = {
/* As SETUP_FINALLY, but push lasti as well */
NOP,
};
pseudo(SETUP_WITH, (HAS_ARG)) = {
pseudo(SETUP_WITH, (-- unused), (HAS_ARG)) = {
/* If an exception is raised, restore the stack position to the
* position before the result of __(a)enter__ and push 2 values
* before jumping to the handler.
*/
NOP,
};
pseudo(POP_BLOCK) = {
pseudo(POP_BLOCK, (--)) = {
NOP,
};

View File

@ -703,8 +703,10 @@ compiler_set_qualname(struct compiler *c)
static int
stack_effect(int opcode, int oparg, int jump)
{
if (0 <= opcode && opcode <= MAX_REAL_OPCODE) {
if (_PyOpcode_Deopt[opcode] != opcode) {
if (opcode < 0) {
return PY_INVALID_STACK_EFFECT;
}
if ((opcode <= MAX_REAL_OPCODE) && (_PyOpcode_Deopt[opcode] != opcode)) {
// Specialized instructions are not supported.
return PY_INVALID_STACK_EFFECT;
}
@ -713,41 +715,10 @@ stack_effect(int opcode, int oparg, int jump)
if (popped < 0 || pushed < 0) {
return PY_INVALID_STACK_EFFECT;
}
return pushed - popped;
}
// Pseudo ops
switch (opcode) {
case POP_BLOCK:
case JUMP:
case JUMP_NO_INTERRUPT:
if (IS_BLOCK_PUSH_OPCODE(opcode) && !jump) {
return 0;
/* Exception handling pseudo-instructions */
case SETUP_FINALLY:
/* 0 in the normal flow.
* Restore the stack position and push 1 value before jumping to
* the handler if an exception be raised. */
return jump ? 1 : 0;
case SETUP_CLEANUP:
/* As SETUP_FINALLY, but pushes lasti as well */
return jump ? 2 : 0;
case SETUP_WITH:
/* 0 in the normal flow.
* Restore the stack position to the position before the result
* of __(a)enter__ and push 2 values before jumping to the handler
* if an exception be raised. */
return jump ? 1 : 0;
case STORE_FAST_MAYBE_NULL:
return -1;
case LOAD_CLOSURE:
return 1;
default:
return PY_INVALID_STACK_EFFECT;
}
return PY_INVALID_STACK_EFFECT; /* not reachable */
return pushed - popped;
}
int

View File

@ -235,6 +235,7 @@ class Instruction:
@dataclass
class PseudoInstruction:
name: str
stack: StackEffect
targets: list[Instruction]
flags: list[str]
opcode: int = -1
@ -295,7 +296,7 @@ def convert_stack_item(item: parser.StackEffect, replace_op_arg_1: str | None) -
item.name, item.type, cond, (item.size or "1")
)
def analyze_stack(op: parser.InstDef, replace_op_arg_1: str | None = None) -> StackEffect:
def analyze_stack(op: parser.InstDef | parser.Pseudo, replace_op_arg_1: str | None = None) -> StackEffect:
inputs: list[StackItem] = [
convert_stack_item(i, replace_op_arg_1) for i in op.inputs if isinstance(i, parser.StackEffect)
]
@ -706,6 +707,7 @@ def add_pseudo(
) -> None:
pseudos[pseudo.name] = PseudoInstruction(
pseudo.name,
analyze_stack(pseudo),
[instructions[target] for target in pseudo.targets],
pseudo.flags,
)

View File

@ -124,7 +124,13 @@ and a piece of C code describing its semantics::
"family" "(" NAME ")" = "{" NAME ("," NAME)+ [","] "}" ";"
pseudo:
"pseudo" "(" NAME ")" = "{" NAME ("," NAME)+ [","] "}" ";"
"pseudo" "(" NAME "," stack_effect ["," "(" flags ")"]")" = "{" NAME ("," NAME)+ [","] "}" ";"
flags:
flag ("|" flag)*
flag:
HAS_ARG | HAS_DEOPT | etc..
```
The following definitions may occur:

View File

@ -10,6 +10,7 @@ import sys
from analyzer import (
Analysis,
Instruction,
PseudoInstruction,
analyze_files,
Skip,
Uop,
@ -94,12 +95,18 @@ def emit_stack_effect_function(
def generate_stack_effect_functions(analysis: Analysis, out: CWriter) -> None:
popped_data: list[tuple[str, str]] = []
pushed_data: list[tuple[str, str]] = []
for inst in analysis.instructions.values():
def add(inst: Instruction | PseudoInstruction) -> None:
stack = get_stack_effect(inst)
popped = (-stack.base_offset).to_c()
pushed = (stack.top_offset - stack.base_offset).to_c()
popped_data.append((inst.name, popped))
pushed_data.append((inst.name, pushed))
for inst in analysis.instructions.values():
add(inst)
for pseudo in analysis.pseudos.values():
add(pseudo)
emit_stack_effect_function(out, "popped", sorted(popped_data))
emit_stack_effect_function(out, "pushed", sorted(pushed_data))

View File

@ -138,6 +138,8 @@ class Family(Node):
@dataclass
class Pseudo(Node):
name: str
inputs: list[InputEffect]
outputs: list[OutputEffect]
flags: list[str] # instr flags to set on the pseudo instruction
targets: list[str] # opcodes this can be replaced by
@ -408,6 +410,8 @@ class Parser(PLexer):
size = None
if self.expect(lx.LPAREN):
if tkn := self.expect(lx.IDENTIFIER):
if self.expect(lx.COMMA):
inp, outp = self.io_effect()
if self.expect(lx.COMMA):
flags = self.flags()
else:
@ -418,7 +422,7 @@ class Parser(PLexer):
raise self.make_syntax_error("Expected {")
if members := self.members():
if self.expect(lx.RBRACE) and self.expect(lx.SEMI):
return Pseudo(tkn.text, flags, members)
return Pseudo(tkn.text, inp, outp, flags, members)
return None
def members(self) -> list[str] | None:

View File

@ -1,7 +1,8 @@
import re
from analyzer import StackItem, Instruction, Uop
from analyzer import StackItem, StackEffect, Instruction, Uop, PseudoInstruction
from dataclasses import dataclass
from cwriter import CWriter
from typing import Iterator
UNUSED = {"unused"}
@ -208,13 +209,20 @@ class Stack:
return f"/* Variables: {[v.name for v in self.variables]}. Base offset: {self.base_offset.to_c()}. Top offset: {self.top_offset.to_c()} */"
def get_stack_effect(inst: Instruction) -> Stack:
def get_stack_effect(inst: Instruction | PseudoInstruction) -> Stack:
stack = Stack()
def stacks(inst : Instruction | PseudoInstruction) -> Iterator[StackEffect]:
if isinstance(inst, Instruction):
for uop in inst.parts:
if not isinstance(uop, Uop):
continue
for var in reversed(uop.stack.inputs):
if isinstance(uop, Uop):
yield uop.stack
else:
assert isinstance(inst, PseudoInstruction)
yield inst.stack
for s in stacks(inst):
for var in reversed(s.inputs):
stack.pop(var)
for i, var in enumerate(uop.stack.outputs):
for var in s.outputs:
stack.push(var)
return stack