bool
scev_is_linear_expression (tree scev)
{
if (scev == NULL
|| !operator_is_linear (scev))
return false;
if (TREE_CODE (scev) == MULT_EXPR)
return !(tree_contains_chrecs (TREE_OPERAND (scev, 0), NULL)
&& tree_contains_chrecs (TREE_OPERAND (scev, 1), NULL));
switch (TREE_CODE_LENGTH (TREE_CODE (scev)))
{
case 3:
return scev_is_linear_expression (TREE_OPERAND (scev, 0))
&& scev_is_linear_expression (TREE_OPERAND (scev, 1))
&& scev_is_linear_expression (TREE_OPERAND (scev, 2));
case 2:
return scev_is_linear_expression (TREE_OPERAND (scev, 0))
&& scev_is_linear_expression (TREE_OPERAND (scev, 1));
case 1:
return scev_is_linear_expression (TREE_OPERAND (scev, 0));
case 0:
return true;
default:
return false;
}
}
bool
tree_contains_chrecs (tree expr, int *size)
{
if (expr == NULL_TREE)
return false;
if (size)
(*size)++;
if (tree_is_chrec (expr))
return true;
switch (TREE_CODE_LENGTH (TREE_CODE (expr)))
{
case 3:
if (tree_contains_chrecs (TREE_OPERAND (expr, 2), size))
return true;
case 2:
if (tree_contains_chrecs (TREE_OPERAND (expr, 1), size))
return true;
case 1:
if (tree_contains_chrecs (TREE_OPERAND (expr, 0), size))
return true;
default:
return false;
}
}
static bool
graphite_can_represent_scev (tree scev)
{
if (chrec_contains_undetermined (scev))
return false;
/* We disable the handling of pointer types, because it’s currently not
supported by Graphite with the ISL AST generator. SSA_NAME nodes are
the only nodes, which are disabled in case they are pointers to object
types, but this can be changed. */
if (POINTER_TYPE_P (TREE_TYPE (scev)) && TREE_CODE (scev) == SSA_NAME)
return false;
switch (TREE_CODE (scev))
{
case NEGATE_EXPR:
case BIT_NOT_EXPR:
CASE_CONVERT:
case NON_LVALUE_EXPR:
return graphite_can_represent_scev (TREE_OPERAND (scev, 0));
case PLUS_EXPR:
case POINTER_PLUS_EXPR:
case MINUS_EXPR:
return graphite_can_represent_scev (TREE_OPERAND (scev, 0))
&& graphite_can_represent_scev (TREE_OPERAND (scev, 1));
case MULT_EXPR:
return !CONVERT_EXPR_CODE_P (TREE_CODE (TREE_OPERAND (scev, 0)))
&& !CONVERT_EXPR_CODE_P (TREE_CODE (TREE_OPERAND (scev, 1)))
&& !(chrec_contains_symbols (TREE_OPERAND (scev, 0))
&& chrec_contains_symbols (TREE_OPERAND (scev, 1)))
&& graphite_can_represent_init (scev)
&& graphite_can_represent_scev (TREE_OPERAND (scev, 0))
&& graphite_can_represent_scev (TREE_OPERAND (scev, 1));
case POLYNOMIAL_CHREC:
/* Check for constant strides. With a non constant stride of
'n' we would have a value of 'iv * n'. Also check that the
initial value can represented: for example 'n * m' cannot be
represented. */
if (!evolution_function_right_is_integer_cst (scev)
|| !graphite_can_represent_init (scev))
return false;
return graphite_can_represent_scev (CHREC_LEFT (scev));
default:
break;
}
/* Only affine functions can be represented. */
if (tree_contains_chrecs (scev, NULL)
|| !scev_is_linear_expression (scev))
return false;
return true;
}
bool
evolution_function_is_univariate_p (const_tree chrec)
{
if (chrec == NULL_TREE)
return true;
switch (TREE_CODE (chrec))
{
case POLYNOMIAL_CHREC:
switch (TREE_CODE (CHREC_LEFT (chrec)))
{
case POLYNOMIAL_CHREC:
if (CHREC_VARIABLE (chrec) != CHREC_VARIABLE (CHREC_LEFT (chrec)))
return false;
if (!evolution_function_is_univariate_p (CHREC_LEFT (chrec)))
return false;
break;
default:
if (tree_contains_chrecs (CHREC_LEFT (chrec), NULL))
return false;
break;
}
switch (TREE_CODE (CHREC_RIGHT (chrec)))
{
case POLYNOMIAL_CHREC:
if (CHREC_VARIABLE (chrec) != CHREC_VARIABLE (CHREC_RIGHT (chrec)))
return false;
if (!evolution_function_is_univariate_p (CHREC_RIGHT (chrec)))
return false;
break;
default:
if (tree_contains_chrecs (CHREC_RIGHT (chrec), NULL))
return false;
break;
}
default:
return true;
}
}
static bool
graphite_can_represent_scev (tree scev)
{
if (chrec_contains_undetermined (scev))
return false;
switch (TREE_CODE (scev))
{
case NEGATE_EXPR:
case BIT_NOT_EXPR:
CASE_CONVERT:
case NON_LVALUE_EXPR:
return graphite_can_represent_scev (TREE_OPERAND (scev, 0));
case PLUS_EXPR:
case POINTER_PLUS_EXPR:
case MINUS_EXPR:
return graphite_can_represent_scev (TREE_OPERAND (scev, 0))
&& graphite_can_represent_scev (TREE_OPERAND (scev, 1));
case MULT_EXPR:
return !CONVERT_EXPR_CODE_P (TREE_CODE (TREE_OPERAND (scev, 0)))
&& !CONVERT_EXPR_CODE_P (TREE_CODE (TREE_OPERAND (scev, 1)))
&& !(chrec_contains_symbols (TREE_OPERAND (scev, 0))
&& chrec_contains_symbols (TREE_OPERAND (scev, 1)))
&& graphite_can_represent_init (scev)
&& graphite_can_represent_scev (TREE_OPERAND (scev, 0))
&& graphite_can_represent_scev (TREE_OPERAND (scev, 1));
case POLYNOMIAL_CHREC:
/* Check for constant strides. With a non constant stride of
'n' we would have a value of 'iv * n'. Also check that the
initial value can represented: for example 'n * m' cannot be
represented. */
if (!evolution_function_right_is_integer_cst (scev)
|| !graphite_can_represent_init (scev))
return false;
return graphite_can_represent_scev (CHREC_LEFT (scev));
default:
break;
}
/* Only affine functions can be represented. */
if (tree_contains_chrecs (scev, NULL)
|| !scev_is_linear_expression (scev))
return false;
return true;
}
bool
scev_is_linear_expression (tree scev)
{
if (scev == NULL
|| !operator_is_linear (scev))
return false;
if (TREE_CODE (scev) == MULT_EXPR)
return !(tree_contains_chrecs (TREE_OPERAND (scev, 0), NULL)
&& tree_contains_chrecs (TREE_OPERAND (scev, 1), NULL));
if (TREE_CODE (scev) == POLYNOMIAL_CHREC
&& !evolution_function_is_affine_multivariate_p (scev, CHREC_VARIABLE (scev)))
return false;
switch (TREE_CODE_LENGTH (TREE_CODE (scev)))
{
case 3:
return scev_is_linear_expression (TREE_OPERAND (scev, 0))
&& scev_is_linear_expression (TREE_OPERAND (scev, 1))
&& scev_is_linear_expression (TREE_OPERAND (scev, 2));
case 2:
return scev_is_linear_expression (TREE_OPERAND (scev, 0))
&& scev_is_linear_expression (TREE_OPERAND (scev, 1));
case 1:
return scev_is_linear_expression (TREE_OPERAND (scev, 0));
case 0:
return true;
default:
return false;
}
}
bool
tree_contains_chrecs (const_tree expr, int *size)
{
int i, n;
if (expr == NULL_TREE)
return false;
if (size)
(*size)++;
if (tree_is_chrec (expr))
return true;
n = TREE_OPERAND_LENGTH (expr);
for (i = 0; i < n; i++)
if (tree_contains_chrecs (TREE_OPERAND (expr, i), size))
return true;
return false;
}
tree
chrec_fold_multiply (tree type,
tree op0,
tree op1)
{
if (automatically_generated_chrec_p (op0)
|| automatically_generated_chrec_p (op1))
return chrec_fold_automatically_generated_operands (op0, op1);
switch (TREE_CODE (op0))
{
case POLYNOMIAL_CHREC:
gcc_checking_assert
(!chrec_contains_symbols_defined_in_loop (op0, CHREC_VARIABLE (op0)));
switch (TREE_CODE (op1))
{
case POLYNOMIAL_CHREC:
gcc_checking_assert
(!chrec_contains_symbols_defined_in_loop (op1,
CHREC_VARIABLE (op1)));
return chrec_fold_multiply_poly_poly (type, op0, op1);
CASE_CONVERT:
if (tree_contains_chrecs (op1, NULL))
return chrec_dont_know;
default:
if (integer_onep (op1))
return op0;
if (integer_zerop (op1))
return build_int_cst (type, 0);
return build_polynomial_chrec
(CHREC_VARIABLE (op0),
chrec_fold_multiply (type, CHREC_LEFT (op0), op1),
chrec_fold_multiply (type, CHREC_RIGHT (op0), op1));
}
CASE_CONVERT:
if (tree_contains_chrecs (op0, NULL))
return chrec_dont_know;
default:
if (integer_onep (op0))
return op1;
if (integer_zerop (op0))
return build_int_cst (type, 0);
switch (TREE_CODE (op1))
{
case POLYNOMIAL_CHREC:
gcc_checking_assert
(!chrec_contains_symbols_defined_in_loop (op1,
CHREC_VARIABLE (op1)));
return build_polynomial_chrec
(CHREC_VARIABLE (op1),
chrec_fold_multiply (type, CHREC_LEFT (op1), op0),
chrec_fold_multiply (type, CHREC_RIGHT (op1), op0));
CASE_CONVERT:
if (tree_contains_chrecs (op1, NULL))
return chrec_dont_know;
default:
if (integer_onep (op1))
return op0;
if (integer_zerop (op1))
return build_int_cst (type, 0);
return fold_build2 (MULT_EXPR, type, op0, op1);
}
}
}
static tree
chrec_fold_plus_1 (enum tree_code code, tree type,
tree op0, tree op1)
{
if (automatically_generated_chrec_p (op0)
|| automatically_generated_chrec_p (op1))
return chrec_fold_automatically_generated_operands (op0, op1);
switch (TREE_CODE (op0))
{
case POLYNOMIAL_CHREC:
gcc_checking_assert
(!chrec_contains_symbols_defined_in_loop (op0, CHREC_VARIABLE (op0)));
switch (TREE_CODE (op1))
{
case POLYNOMIAL_CHREC:
gcc_checking_assert
(!chrec_contains_symbols_defined_in_loop (op1,
CHREC_VARIABLE (op1)));
return chrec_fold_plus_poly_poly (code, type, op0, op1);
CASE_CONVERT:
if (tree_contains_chrecs (op1, NULL))
return chrec_dont_know;
default:
if (code == PLUS_EXPR || code == POINTER_PLUS_EXPR)
return build_polynomial_chrec
(CHREC_VARIABLE (op0),
chrec_fold_plus (type, CHREC_LEFT (op0), op1),
CHREC_RIGHT (op0));
else
return build_polynomial_chrec
(CHREC_VARIABLE (op0),
chrec_fold_minus (type, CHREC_LEFT (op0), op1),
CHREC_RIGHT (op0));
}
CASE_CONVERT:
if (tree_contains_chrecs (op0, NULL))
return chrec_dont_know;
default:
switch (TREE_CODE (op1))
{
case POLYNOMIAL_CHREC:
gcc_checking_assert
(!chrec_contains_symbols_defined_in_loop (op1,
CHREC_VARIABLE (op1)));
if (code == PLUS_EXPR || code == POINTER_PLUS_EXPR)
return build_polynomial_chrec
(CHREC_VARIABLE (op1),
chrec_fold_plus (type, op0, CHREC_LEFT (op1)),
CHREC_RIGHT (op1));
else
return build_polynomial_chrec
(CHREC_VARIABLE (op1),
chrec_fold_minus (type, op0, CHREC_LEFT (op1)),
chrec_fold_multiply (type, CHREC_RIGHT (op1),
SCALAR_FLOAT_TYPE_P (type)
? build_real (type, dconstm1)
: build_int_cst_type (type, -1)));
CASE_CONVERT:
if (tree_contains_chrecs (op1, NULL))
return chrec_dont_know;
default:
{
int size = 0;
if ((tree_contains_chrecs (op0, &size)
|| tree_contains_chrecs (op1, &size))
&& size < PARAM_VALUE (PARAM_SCEV_MAX_EXPR_SIZE))
return build2 (code, type, op0, op1);
else if (size < PARAM_VALUE (PARAM_SCEV_MAX_EXPR_SIZE))
{
if (code == POINTER_PLUS_EXPR)
return fold_build_pointer_plus (fold_convert (type, op0),
op1);
else
return fold_build2 (code, type,
fold_convert (type, op0),
fold_convert (type, op1));
}
else
return chrec_dont_know;
}
}
}
}
static tree
chrec_fold_plus_1 (enum tree_code code,
tree type,
tree op0,
tree op1)
{
if (automatically_generated_chrec_p (op0)
|| automatically_generated_chrec_p (op1))
return chrec_fold_automatically_generated_operands (op0, op1);
switch (TREE_CODE (op0))
{
case POLYNOMIAL_CHREC:
switch (TREE_CODE (op1))
{
case POLYNOMIAL_CHREC:
return chrec_fold_plus_poly_poly (code, type, op0, op1);
default:
if (code == PLUS_EXPR)
return build_polynomial_chrec
(CHREC_VARIABLE (op0),
chrec_fold_plus (type, CHREC_LEFT (op0), op1),
CHREC_RIGHT (op0));
else
return build_polynomial_chrec
(CHREC_VARIABLE (op0),
chrec_fold_minus (type, CHREC_LEFT (op0), op1),
CHREC_RIGHT (op0));
}
default:
switch (TREE_CODE (op1))
{
case POLYNOMIAL_CHREC:
if (code == PLUS_EXPR)
return build_polynomial_chrec
(CHREC_VARIABLE (op1),
chrec_fold_plus (type, op0, CHREC_LEFT (op1)),
CHREC_RIGHT (op1));
else
return build_polynomial_chrec
(CHREC_VARIABLE (op1),
chrec_fold_minus (type, op0, CHREC_LEFT (op1)),
chrec_fold_multiply (type, CHREC_RIGHT (op1),
build_int_cst_type (type, -1)));
default:
{
int size = 0;
if ((tree_contains_chrecs (op0, &size)
|| tree_contains_chrecs (op1, &size))
&& size < PARAM_VALUE (PARAM_SCEV_MAX_EXPR_SIZE))
return build2 (code, type, op0, op1);
else if (size < PARAM_VALUE (PARAM_SCEV_MAX_EXPR_SIZE))
return fold (build2 (code, type, op0, op1));
else
return chrec_dont_know;
}
}
}
}
