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gh-115480: Type and constant propagation for int BINARY_OPs #115478

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Merged
merged 2 commits into from
Feb 15, 2024
Merged

gh-115480: Type and constant propagation for int BINARY_OPs #115478

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edb4fcf
Type and constant propagation for int BINARY_OPs
Fidget-Spinner Feb 14, 2024
6ca3f78
add asserts
Fidget-Spinner Feb 14, 2024
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12 changes: 12 additions & 0 deletions Python/optimizer_analysis.c
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Original file line number Diff line number Diff line change
Expand Up @@ -341,6 +341,18 @@ sym_new_const(_Py_UOpsAbstractInterpContext *ctx, PyObject *const_val)
return temp;
}

static inline bool
is_const(_Py_UOpsSymType *sym)
{
return sym->const_val != NULL;
}

static inline PyObject *
get_const(_Py_UOpsSymType *sym)
{
return sym->const_val;
}

static _Py_UOpsSymType*
sym_new_null(_Py_UOpsAbstractInterpContext *ctx)
{
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62 changes: 56 additions & 6 deletions Python/tier2_redundancy_eliminator_bytecodes.c
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Expand Up @@ -81,12 +81,62 @@ dummy_func(void) {


op(_BINARY_OP_ADD_INT, (left, right -- res)) {
// TODO constant propagation
(void)left;
(void)right;
res = sym_new_known_type(ctx, &PyLong_Type);
if (res == NULL) {
goto out_of_space;
if (is_const(left) && is_const(right)) {
assert(PyLong_CheckExact(get_const(left)));
assert(PyLong_CheckExact(get_const(right)));
PyObject *temp = _PyLong_Add((PyLongObject *)get_const(left),
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@markshannon markshannon Feb 21, 2024 •
edited
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This may leak, if temp is mortal.
Likewise for the other _BINARY_OP_... below.

Symbols hold a strong reference to constants, so there is no leak.

(PyLongObject *)get_const(right));
if (temp == NULL) {
goto error;
}
res = sym_new_const(ctx, temp);
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Missing NULL check

// TODO replace opcode with constant propagated one and add tests!
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@markshannon markshannon Feb 15, 2024 •
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In future, please make a new issue for this sort of TODOs.

}
else {
res = sym_new_known_type(ctx, &PyLong_Type);
if (res == NULL) {
goto out_of_space;
}
}
}

op(_BINARY_OP_SUBTRACT_INT, (left, right -- res)) {
if (is_const(left) && is_const(right)) {
assert(PyLong_CheckExact(get_const(left)));
assert(PyLong_CheckExact(get_const(right)));
PyObject *temp = _PyLong_Subtract((PyLongObject *)get_const(left),
(PyLongObject *)get_const(right));
if (temp == NULL) {
goto error;
}
res = sym_new_const(ctx, temp);
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Missing NULL check

// TODO replace opcode with constant propagated one and add tests!
}
else {
res = sym_new_known_type(ctx, &PyLong_Type);
if (res == NULL) {
goto out_of_space;
}
}
}

op(_BINARY_OP_MULTIPLY_INT, (left, right -- res)) {
if (is_const(left) && is_const(right)) {
assert(PyLong_CheckExact(get_const(left)));
assert(PyLong_CheckExact(get_const(right)));
PyObject *temp = _PyLong_Multiply((PyLongObject *)get_const(left),
(PyLongObject *)get_const(right));
if (temp == NULL) {
goto error;
}
res = sym_new_const(ctx, temp);
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Missing NULL check

// TODO replace opcode with constant propagated one and add tests!
}
else {
res = sym_new_known_type(ctx, &PyLong_Type);
if (res == NULL) {
goto out_of_space;
}
}
}

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68 changes: 58 additions & 10 deletions Python/tier2_redundancy_eliminator_cases.c.h
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Original file line number Diff line number Diff line change
Expand Up @@ -180,9 +180,28 @@
}

case _BINARY_OP_MULTIPLY_INT: {
_Py_UOpsSymType *right;
_Py_UOpsSymType *left;
_Py_UOpsSymType *res;
res = sym_new_unknown(ctx);
if (res == NULL) goto out_of_space;
right = stack_pointer[-1];
left = stack_pointer[-2];
if (is_const(left) && is_const(right)) {
assert(PyLong_CheckExact(get_const(left)));
assert(PyLong_CheckExact(get_const(right)));
PyObject *temp = _PyLong_Multiply((PyLongObject *)get_const(left),
(PyLongObject *)get_const(right));
if (temp == NULL) {
goto error;
}
res = sym_new_const(ctx, temp);
// TODO replace opcode with constant propagated one and add tests!
}
else {
res = sym_new_known_type(ctx, &PyLong_Type);
if (res == NULL) {
goto out_of_space;
}
}
stack_pointer[-2] = res;
stack_pointer += -1;
break;
Expand All @@ -194,22 +213,51 @@
_Py_UOpsSymType *res;
right = stack_pointer[-1];
left = stack_pointer[-2];
// TODO constant propagation
(void)left;
(void)right;
res = sym_new_known_type(ctx, &PyLong_Type);
if (res == NULL) {
goto out_of_space;
if (is_const(left) && is_const(right)) {
assert(PyLong_CheckExact(get_const(left)));
assert(PyLong_CheckExact(get_const(right)));
PyObject *temp = _PyLong_Add((PyLongObject *)get_const(left),
(PyLongObject *)get_const(right));
if (temp == NULL) {
goto error;
}
res = sym_new_const(ctx, temp);
// TODO replace opcode with constant propagated one and add tests!
}
else {
res = sym_new_known_type(ctx, &PyLong_Type);
if (res == NULL) {
goto out_of_space;
}
}
stack_pointer[-2] = res;
stack_pointer += -1;
break;
}

case _BINARY_OP_SUBTRACT_INT: {
_Py_UOpsSymType *right;
_Py_UOpsSymType *left;
_Py_UOpsSymType *res;
res = sym_new_unknown(ctx);
if (res == NULL) goto out_of_space;
right = stack_pointer[-1];
left = stack_pointer[-2];
if (is_const(left) && is_const(right)) {
assert(PyLong_CheckExact(get_const(left)));
assert(PyLong_CheckExact(get_const(right)));
PyObject *temp = _PyLong_Subtract((PyLongObject *)get_const(left),
(PyLongObject *)get_const(right));
if (temp == NULL) {
goto error;
}
res = sym_new_const(ctx, temp);
// TODO replace opcode with constant propagated one and add tests!
}
else {
res = sym_new_known_type(ctx, &PyLong_Type);
if (res == NULL) {
goto out_of_space;
}
}
stack_pointer[-2] = res;
stack_pointer += -1;
break;
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