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"""Wrapping existing analysis utils."""

# pylint: disable=invalid-name

from tvm.ir import IRModule
from tvm.tirx.expr import Var
from tvm.tirx.stmt import Expr

from .. import Stmt
from ..function import PrimFunc
from . import _ffi_api


def expr_deep_equal(lhs: Expr, rhs: Expr) -> bool:
    """Deeply compare two nested expressions.

    Parameters
    ----------
    lhs : Expr
        The left operand.

    rhs : Expr
        The right operand.

    Returns
    -------
    result : bool
        The comparison result

    Note
    ----

    This function does not remap variable bindings, it will not
    return true for (let x = 1 in x + 1) vs (let y = 1 in y + 1), unless x.same_as(y).
    Use py:func:`tvm_ffi.structural_equal` to handle structural variable remapping.

    Due to the restriction of not remapping variables, this function can run
    faster than StructuralEqual and can be used as a utility function during arithmetic
    simplifications.

    Always consider py:func:`tvm_ffi.structural_equal` first, which handles
    the structural remapping.

    See Also
    --------
    tvm_ffi.structural_equal
    """
    return _ffi_api.expr_deep_equal(lhs, rhs)  # type: ignore


def verify_ssa(func: PrimFunc) -> bool:
    """Verify if the func is in SSA form.

    Parameters
    ----------
    func: tvm.tirx.PrimFunc
        The module to be verified.

    Returns
    -------
    result : bool
        The result of verification.
    """
    return _ffi_api.verify_ssa(func)  # type: ignore


def verify_memory(func: PrimFunc) -> bool:
    """Verify if func contains illegal host side direct memory access.

    Parameters
    ----------
    func: tvm.tirx.PrimFunc
        The module to be verified.

    Returns
    -------
    result : bool
        The result of verification.
    """
    return _ffi_api.verify_memory(func)  # type: ignore


def undefined_vars(node: Stmt | Expr, defs: list[Var] | None = None) -> list[Var]:
    """Find undefined vars in a TIR statement or expression.

    Parameters
    ----------
    node: Union[Stmt, Expr]
        The TIR statement or expression to be checked.

    defs: Optional[List[Var]]
        The vars that is defined

    Returns
    -------
    result : List[Var]
        The undefined vars.
    """
    defs = defs or []
    return _ffi_api.UndefinedVars(node, defs)  # type: ignore # pylint: disable=no-member


def verify_well_formed(obj: PrimFunc | IRModule, assert_mode: bool = True) -> bool:
    """Verify if the given TIR is well-formed. The verification includes:
        - Check if expressions not contain vars that is defined outside the block.

    Parameters
    ----------
    obj: Union[tvm.tirx.PrimFunc, tvm.ir.IRModule]
        The function or module to be verified.

    assert_mode: bool
        The indicator if it raises an error when the function is not well-formed.

    Returns
    -------
    result: bool
        Whether it is a well-formed TIR function.
    """
    return _ffi_api.VerifyWellFormed(obj, assert_mode)  # type: ignore # pylint: disable=no-member


def verify_tirx_well_formed(
    obj: PrimFunc | IRModule, assert_mode: bool = True, device_func: bool = False
) -> bool:
    """Verify if the given TIRX is well-formed.

    Parameters
    ----------
    obj: Union[tvm.tirx.PrimFunc, tvm.ir.IRModule]
        The function or module to be verified.

    assert_mode: bool
        The indicator if it raises an error when the function is not well-formed.

    device_func: bool
        The indicator if it is a device function.

    Returns
    -------
    result: bool
        Whether it is a well-formed TIRX function.
    """
    return _ffi_api.VerifyTIRxWellFormed(obj, assert_mode, device_func)  # type: ignore # pylint: disable=no-member