static bool
process_assignment (gimple stmt, gimple_stmt_iterator call, tree *m,
tree *a, tree *ass_var)
{
tree op0, op1 = NULL_TREE, non_ass_var = NULL_TREE;
tree dest = gimple_assign_lhs (stmt);
enum tree_code code = gimple_assign_rhs_code (stmt);
enum gimple_rhs_class rhs_class = get_gimple_rhs_class (code);
tree src_var = gimple_assign_rhs1 (stmt);
/* See if this is a simple copy operation of an SSA name to the function
result. In that case we may have a simple tail call. Ignore type
conversions that can never produce extra code between the function
call and the function return. */
if ((rhs_class == GIMPLE_SINGLE_RHS || gimple_assign_cast_p (stmt))
&& (TREE_CODE (src_var) == SSA_NAME))
{
/* Reject a tailcall if the type conversion might need
additional code. */
if (gimple_assign_cast_p (stmt))
{
if (TYPE_MODE (TREE_TYPE (dest)) != TYPE_MODE (TREE_TYPE (src_var)))
return false;
/* Even if the type modes are the same, if the precision of the
type is smaller than mode's precision,
reduce_to_bit_field_precision would generate additional code. */
if (INTEGRAL_TYPE_P (TREE_TYPE (dest))
&& (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (dest)))
> TYPE_PRECISION (TREE_TYPE (dest))))
return false;
}
if (src_var != *ass_var)
return false;
*ass_var = dest;
return true;
}
switch (rhs_class)
{
case GIMPLE_BINARY_RHS:
op1 = gimple_assign_rhs2 (stmt);
/* Fall through. */
case GIMPLE_UNARY_RHS:
op0 = gimple_assign_rhs1 (stmt);
break;
default:
return false;
}
/* Accumulator optimizations will reverse the order of operations.
We can only do that for floating-point types if we're assuming
that addition and multiplication are associative. */
if (!flag_associative_math)
if (FLOAT_TYPE_P (TREE_TYPE (DECL_RESULT (current_function_decl))))
return false;
if (rhs_class == GIMPLE_UNARY_RHS)
;
else if (op0 == *ass_var
&& (non_ass_var = independent_of_stmt_p (op1, stmt, call)))
;
else if (op1 == *ass_var
&& (non_ass_var = independent_of_stmt_p (op0, stmt, call)))
;
else
return false;
switch (code)
{
case PLUS_EXPR:
*a = non_ass_var;
*ass_var = dest;
return true;
case POINTER_PLUS_EXPR:
if (op0 != *ass_var)
return false;
*a = non_ass_var;
*ass_var = dest;
return true;
case MULT_EXPR:
*m = non_ass_var;
*ass_var = dest;
return true;
case NEGATE_EXPR:
*m = build_minus_one_cst (TREE_TYPE (op0));
*ass_var = dest;
return true;
case MINUS_EXPR:
if (*ass_var == op0)
*a = fold_build1 (NEGATE_EXPR, TREE_TYPE (non_ass_var), non_ass_var);
else
{
*m = build_minus_one_cst (TREE_TYPE (non_ass_var));
*a = fold_build1 (NEGATE_EXPR, TREE_TYPE (non_ass_var), non_ass_var);
}
*ass_var = dest;
return true;
/* TODO -- Handle POINTER_PLUS_EXPR. */
default:
return false;
}
}
tree
ubsan_instrument_float_cast (location_t loc, tree type, tree expr)
{
tree expr_type = TREE_TYPE (expr);
tree t, tt, fn, min, max;
enum machine_mode mode = TYPE_MODE (expr_type);
int prec = TYPE_PRECISION (type);
bool uns_p = TYPE_UNSIGNED (type);
/* Float to integer conversion first truncates toward zero, so
even signed char c = 127.875f; is not problematic.
Therefore, we should complain only if EXPR is unordered or smaller
or equal than TYPE_MIN_VALUE - 1.0 or greater or equal than
TYPE_MAX_VALUE + 1.0. */
if (REAL_MODE_FORMAT (mode)->b == 2)
{
/* For maximum, TYPE_MAX_VALUE might not be representable
in EXPR_TYPE, e.g. if TYPE is 64-bit long long and
EXPR_TYPE is IEEE single float, but TYPE_MAX_VALUE + 1.0 is
either representable or infinity. */
REAL_VALUE_TYPE maxval = dconst1;
SET_REAL_EXP (&maxval, REAL_EXP (&maxval) + prec - !uns_p);
real_convert (&maxval, mode, &maxval);
max = build_real (expr_type, maxval);
/* For unsigned, assume -1.0 is always representable. */
if (uns_p)
min = build_minus_one_cst (expr_type);
else
{
/* TYPE_MIN_VALUE is generally representable (or -inf),
but TYPE_MIN_VALUE - 1.0 might not be. */
REAL_VALUE_TYPE minval = dconstm1, minval2;
SET_REAL_EXP (&minval, REAL_EXP (&minval) + prec - 1);
real_convert (&minval, mode, &minval);
real_arithmetic (&minval2, MINUS_EXPR, &minval, &dconst1);
real_convert (&minval2, mode, &minval2);
if (real_compare (EQ_EXPR, &minval, &minval2)
&& !real_isinf (&minval))
{
/* If TYPE_MIN_VALUE - 1.0 is not representable and
rounds to TYPE_MIN_VALUE, we need to subtract
more. As REAL_MODE_FORMAT (mode)->p is the number
of base digits, we want to subtract a number that
will be 1 << (REAL_MODE_FORMAT (mode)->p - 1)
times smaller than minval. */
minval2 = dconst1;
gcc_assert (prec > REAL_MODE_FORMAT (mode)->p);
SET_REAL_EXP (&minval2,
REAL_EXP (&minval2) + prec - 1
- REAL_MODE_FORMAT (mode)->p + 1);
real_arithmetic (&minval2, MINUS_EXPR, &minval, &minval2);
real_convert (&minval2, mode, &minval2);
}
min = build_real (expr_type, minval2);
}
}
else if (REAL_MODE_FORMAT (mode)->b == 10)
{
/* For _Decimal128 up to 34 decimal digits, - sign,
dot, e, exponent. */
char buf[64];
mpfr_t m;
int p = REAL_MODE_FORMAT (mode)->p;
REAL_VALUE_TYPE maxval, minval;
/* Use mpfr_snprintf rounding to compute the smallest
representable decimal number greater or equal than
1 << (prec - !uns_p). */
mpfr_init2 (m, prec + 2);
mpfr_set_ui_2exp (m, 1, prec - !uns_p, GMP_RNDN);
mpfr_snprintf (buf, sizeof buf, "%.*RUe", p - 1, m);
decimal_real_from_string (&maxval, buf);
max = build_real (expr_type, maxval);
/* For unsigned, assume -1.0 is always representable. */
if (uns_p)
min = build_minus_one_cst (expr_type);
else
{
/* Use mpfr_snprintf rounding to compute the largest
representable decimal number less or equal than
(-1 << (prec - 1)) - 1. */
mpfr_set_si_2exp (m, -1, prec - 1, GMP_RNDN);
mpfr_sub_ui (m, m, 1, GMP_RNDN);
mpfr_snprintf (buf, sizeof buf, "%.*RDe", p - 1, m);
decimal_real_from_string (&minval, buf);
min = build_real (expr_type, minval);
}
mpfr_clear (m);
}
else
return NULL_TREE;
if (flag_sanitize_undefined_trap_on_error)
fn = build_call_expr_loc (loc, builtin_decl_explicit (BUILT_IN_TRAP), 0);
else
{
/* Create the __ubsan_handle_float_cast_overflow fn call. */
tree data = ubsan_create_data ("__ubsan_float_cast_overflow_data", NULL,
NULL, ubsan_type_descriptor (expr_type),
ubsan_type_descriptor (type), NULL_TREE);
enum built_in_function bcode
= flag_sanitize_recover
? BUILT_IN_UBSAN_HANDLE_FLOAT_CAST_OVERFLOW
: BUILT_IN_UBSAN_HANDLE_FLOAT_CAST_OVERFLOW_ABORT;
fn = builtin_decl_explicit (bcode);
fn = build_call_expr_loc (loc, fn, 2,
build_fold_addr_expr_loc (loc, data),
ubsan_encode_value (expr, false));
}
t = fold_build2 (UNLE_EXPR, boolean_type_node, expr, min);
tt = fold_build2 (UNGE_EXPR, boolean_type_node, expr, max);
return fold_build3 (COND_EXPR, void_type_node,
fold_build2 (TRUTH_OR_EXPR, boolean_type_node, t, tt),
fn, integer_zero_node);
}
