static int compare_values_warnv (tree val1, tree val2, bool *);
static void vrp_meet (value_range_t *, value_range_t *);
static tree vrp_evaluate_conditional_warnv_with_ops (enum tree_code,
- tree, tree, bool, bool *);
+ tree, tree, bool, bool *,
+ bool *);
/* Location information for ASSERT_EXPRs. Each instance of this
structure describes an ASSERT_EXPR for an SSA name. Since a single
&& code != MIN_EXPR
&& code != MAX_EXPR
&& code != BIT_AND_EXPR
+ && code != BIT_IOR_EXPR
&& code != TRUTH_AND_EXPR
&& code != TRUTH_OR_EXPR)
{
/* We can still do constant propagation here. */
- if ((op0 = op_with_constant_singleton_value_range (op0)) != NULL_TREE
- && (op1 = op_with_constant_singleton_value_range (op1)) != NULL_TREE)
+ tree const_op0 = op_with_constant_singleton_value_range (op0);
+ tree const_op1 = op_with_constant_singleton_value_range (op1);
+ if (const_op0 || const_op1)
{
- tree tem = fold_binary (code, expr_type, op0, op1);
- if (is_gimple_min_invariant (tem)
+ tree tem = fold_binary (code, expr_type,
+ const_op0 ? const_op0 : op0,
+ const_op1 ? const_op1 : op1);
+ if (tem
+ && is_gimple_min_invariant (tem)
&& !is_overflow_infinity (tem))
{
set_value_range (vr, VR_RANGE, tem, tem, NULL);
return;
}
}
+ else if (code == BIT_IOR_EXPR)
+ {
+ if (vr0.type == VR_RANGE
+ && vr1.type == VR_RANGE
+ && TREE_CODE (vr0.min) == INTEGER_CST
+ && TREE_CODE (vr1.min) == INTEGER_CST
+ && TREE_CODE (vr0.max) == INTEGER_CST
+ && TREE_CODE (vr1.max) == INTEGER_CST
+ && tree_int_cst_sgn (vr0.min) >= 0
+ && tree_int_cst_sgn (vr1.min) >= 0)
+ {
+ double_int vr0_max = tree_to_double_int (vr0.max);
+ double_int vr1_max = tree_to_double_int (vr1.max);
+ double_int ior_max;
+
+ /* Set all bits to the right of the most significant one to 1.
+ For example, [0, 4] | [4, 4] = [4, 7]. */
+ ior_max.low = vr0_max.low | vr1_max.low;
+ ior_max.high = vr0_max.high | vr1_max.high;
+ if (ior_max.high != 0)
+ {
+ ior_max.low = ~0u;
+ ior_max.high |= ((HOST_WIDE_INT) 1
+ << floor_log2 (ior_max.high)) - 1;
+ }
+ else
+ ior_max.low |= ((unsigned HOST_WIDE_INT) 1u
+ << floor_log2 (ior_max.low)) - 1;
+
+ /* Both of these endpoints are conservative. */
+ min = vrp_int_const_binop (MAX_EXPR, vr0.min, vr1.min);
+ max = double_int_to_tree (expr_type, ior_max);
+ }
+ else
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
+ }
else
gcc_unreachable ();
if ((op0 = op_with_constant_singleton_value_range (op0)) != NULL_TREE)
{
tree tem = fold_unary (code, type, op0);
- if (is_gimple_min_invariant (tem)
+ if (tem
+ && is_gimple_min_invariant (tem)
&& !is_overflow_infinity (tem))
{
set_value_range (vr, VR_RANGE, tem, tem, NULL);
max = fold_unary_to_constant (code, type, vr0.max);
else if (!needs_overflow_infinity (type))
max = TYPE_MAX_VALUE (type);
- else if (supports_overflow_infinity (type))
+ else if (supports_overflow_infinity (type)
+ /* We shouldn't generate [+INF, +INF] as set_value_range
+ doesn't like this and ICEs. */
+ && !is_positive_overflow_infinity (min))
max = positive_overflow_infinity (type);
else
{
bool sop = false;
tree val;
- val = vrp_evaluate_conditional_warnv_with_ops (code, op0, op1, false, &sop);
+ val = vrp_evaluate_conditional_warnv_with_ops (code, op0, op1, false, &sop,
+ NULL);
/* A disadvantage of using a special infinity as an overflow
representation is that we lose the ability to record overflow
&& gimple_code (gsi_stmt (si)) != GIMPLE_SWITCH);
#endif
+ /* Never build an assert comparing against an integer constant with
+ TREE_OVERFLOW set. This confuses our undefined overflow warning
+ machinery. */
+ if (TREE_CODE (val) == INTEGER_CST
+ && TREE_OVERFLOW (val))
+ val = build_int_cst_wide (TREE_TYPE (val),
+ TREE_INT_CST_LOW (val), TREE_INT_CST_HIGH (val));
+
/* The new assertion A will be inserted at BB or E. We need to
determine if the new location is dominated by a previously
registered location for A. If we are doing an edge insertion,
edge e;
tree vec2;
size_t n = gimple_switch_num_labels(last);
+#if GCC_VERSION >= 4000
unsigned int idx;
+#else
+ /* Work around GCC 3.4 bug (PR 37086). */
+ volatile unsigned int idx;
+#endif
need_assert = false;
bsi = gsi_for_stmt (last);
return NULL_TREE;
}
+/* Helper function for vrp_evaluate_conditional_warnv. */
+
+static tree
+vrp_evaluate_conditional_warnv_with_ops_using_ranges (enum tree_code code,
+ tree op0, tree op1,
+ bool * strict_overflow_p)
+{
+ value_range_t *vr0, *vr1;
+
+ vr0 = (TREE_CODE (op0) == SSA_NAME) ? get_value_range (op0) : NULL;
+ vr1 = (TREE_CODE (op1) == SSA_NAME) ? get_value_range (op1) : NULL;
+
+ if (vr0 && vr1)
+ return compare_ranges (code, vr0, vr1, strict_overflow_p);
+ else if (vr0 && vr1 == NULL)
+ return compare_range_with_value (code, vr0, op1, strict_overflow_p);
+ else if (vr0 == NULL && vr1)
+ return (compare_range_with_value
+ (swap_tree_comparison (code), vr1, op0, strict_overflow_p));
+ return NULL;
+}
+
/* Helper function for vrp_evaluate_conditional_warnv. */
static tree
vrp_evaluate_conditional_warnv_with_ops (enum tree_code code, tree op0,
tree op1, bool use_equiv_p,
- bool *strict_overflow_p)
+ bool *strict_overflow_p, bool *only_ranges)
{
+ tree ret;
+ if (only_ranges)
+ *only_ranges = true;
+
/* We only deal with integral and pointer types. */
if (!INTEGRAL_TYPE_P (TREE_TYPE (op0))
&& !POINTER_TYPE_P (TREE_TYPE (op0)))
if (use_equiv_p)
{
+ if (only_ranges
+ && (ret = vrp_evaluate_conditional_warnv_with_ops_using_ranges
+ (code, op0, op1, strict_overflow_p)))
+ return ret;
+ *only_ranges = false;
if (TREE_CODE (op0) == SSA_NAME && TREE_CODE (op1) == SSA_NAME)
return compare_names (code, op0, op1, strict_overflow_p);
else if (TREE_CODE (op0) == SSA_NAME)
(swap_tree_comparison (code), op1, op0, strict_overflow_p));
}
else
- {
- value_range_t *vr0, *vr1;
-
- vr0 = (TREE_CODE (op0) == SSA_NAME) ? get_value_range (op0) : NULL;
- vr1 = (TREE_CODE (op1) == SSA_NAME) ? get_value_range (op1) : NULL;
-
- if (vr0 && vr1)
- return compare_ranges (code, vr0, vr1, strict_overflow_p);
- else if (vr0 && vr1 == NULL)
- return compare_range_with_value (code, vr0, op1, strict_overflow_p);
- else if (vr0 == NULL && vr1)
- return (compare_range_with_value
- (swap_tree_comparison (code), vr1, op0, strict_overflow_p));
- }
+ return vrp_evaluate_conditional_warnv_with_ops_using_ranges (code, op0, op1,
+ strict_overflow_p);
return NULL_TREE;
}
{
bool sop;
tree ret;
+ bool only_ranges;
sop = false;
- ret = vrp_evaluate_conditional_warnv_with_ops (code, op0, op1, true, &sop);
+ ret = vrp_evaluate_conditional_warnv_with_ops (code, op0, op1, true, &sop,
+ &only_ranges);
if (ret && sop)
{
}
if (warn_type_limits
- && ret
+ && ret && only_ranges
&& TREE_CODE_CLASS (code) == tcc_comparison
&& TREE_CODE (op0) == SSA_NAME)
{
val = vrp_evaluate_conditional_warnv_with_ops (gimple_cond_code (stmt),
gimple_cond_lhs (stmt),
gimple_cond_rhs (stmt),
- false, &sop);
+ false, &sop, NULL);
if (val)
{
if (!sop)
return SSA_PROP_VARYING;
}
+/* Simplify boolean operations if the source is known
+ to be already a boolean. */
+static bool
+simplify_truth_ops_using_ranges (gimple_stmt_iterator *gsi, gimple stmt)
+{
+ enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
+ tree val = NULL;
+ tree op0, op1;
+ value_range_t *vr;
+ bool sop = false;
+ bool need_conversion;
+
+ op0 = gimple_assign_rhs1 (stmt);
+ vr = get_value_range (op0);
+ if (TYPE_PRECISION (TREE_TYPE (op0)) != 1)
+ {
+ val = compare_range_with_value (GE_EXPR, vr, integer_zero_node, &sop);
+ if (!val || !integer_onep (val))
+ return false;
+
+ val = compare_range_with_value (LE_EXPR, vr, integer_one_node, &sop);
+ if (!val || !integer_onep (val))
+ return false;
+ }
+
+ if (rhs_code == TRUTH_NOT_EXPR)
+ {
+ rhs_code = NE_EXPR;
+ op1 = build_int_cst (TREE_TYPE (op0), 1);
+ }
+ else
+ {
+ op1 = gimple_assign_rhs2 (stmt);
+
+ /* Reduce number of cases to handle. */
+ if (is_gimple_min_invariant (op1))
+ {
+ /* Exclude anything that should have been already folded. */
+ gcc_assert (rhs_code == EQ_EXPR || rhs_code == NE_EXPR
+ || rhs_code == TRUTH_XOR_EXPR);
+ gcc_assert (integer_zerop (op1) || integer_onep (op1)
+ || integer_all_onesp (op1));
+
+ /* Limit the number of cases we have to consider. */
+ if (rhs_code == EQ_EXPR)
+ {
+ rhs_code = NE_EXPR;
+ op1 = fold_unary (TRUTH_NOT_EXPR, TREE_TYPE (op1), op1);
+ }
+ }
+ else
+ {
+ /* Punt on A == B as there is no BIT_XNOR_EXPR. */
+ if (rhs_code == EQ_EXPR)
+ return false;
+
+ if (TYPE_PRECISION (TREE_TYPE (op1)) != 1)
+ {
+ vr = get_value_range (op1);
+ val = compare_range_with_value (GE_EXPR, vr, integer_zero_node, &sop);
+ if (!val || !integer_onep (val))
+ return false;
+
+ val = compare_range_with_value (LE_EXPR, vr, integer_one_node, &sop);
+ if (!val || !integer_onep (val))
+ return false;
+ }
+ }
+ }
+
+ if (sop && issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC))
+ {
+ location_t location;
+
+ if (!gimple_has_location (stmt))
+ location = input_location;
+ else
+ location = gimple_location (stmt);
+
+ if (rhs_code == TRUTH_AND_EXPR || rhs_code == TRUTH_OR_EXPR)
+ warning_at (location, OPT_Wstrict_overflow,
+ _("assuming signed overflow does not occur when "
+ "simplifying && or || to & or |"));
+ else
+ warning_at (location, OPT_Wstrict_overflow,
+ _("assuming signed overflow does not occur when "
+ "simplifying ==, != or ! to identity or ^"));
+ }
+
+ need_conversion =
+ !useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (stmt)),
+ TREE_TYPE (op0));
+
+ switch (rhs_code)
+ {
+ case TRUTH_AND_EXPR:
+ rhs_code = BIT_AND_EXPR;
+ break;
+ case TRUTH_OR_EXPR:
+ rhs_code = BIT_IOR_EXPR;
+ break;
+ case TRUTH_XOR_EXPR:
+ case NE_EXPR:
+ if (integer_zerop (op1))
+ {
+ gimple_assign_set_rhs_with_ops (gsi,
+ need_conversion ? NOP_EXPR : SSA_NAME,
+ op0, NULL);
+ update_stmt (gsi_stmt (*gsi));
+ return true;
+ }
+
+ rhs_code = BIT_XOR_EXPR;
+ break;
+ default:
+ gcc_unreachable ();
+ }
+
+ if (need_conversion)
+ return false;
+
+ gimple_assign_set_rhs_with_ops (gsi, rhs_code, op0, op1);
+ update_stmt (gsi_stmt (*gsi));
+ return true;
+}
+
/* Simplify a division or modulo operator to a right shift or
bitwise and if the first operand is unsigned or is greater
than zero and the second operand is an exact power of two. */
-static void
+static bool
simplify_div_or_mod_using_ranges (gimple stmt)
{
enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
}
update_stmt (stmt);
+ return true;
}
+
+ return false;
}
/* If the operand to an ABS_EXPR is >= 0, then eliminate the
ABS_EXPR. If the operand is <= 0, then simplify the
ABS_EXPR into a NEGATE_EXPR. */
-static void
+static bool
simplify_abs_using_ranges (gimple stmt)
{
tree val = NULL;
else
gimple_assign_set_rhs_code (stmt, SSA_NAME);
update_stmt (stmt);
+ return true;
}
}
+
+ return false;
}
/* We are comparing trees OP0 and OP1 using COND_CODE. OP0 has
test if the range information indicates only one value can satisfy
the original conditional. */
-static void
+static bool
simplify_cond_using_ranges (gimple stmt)
{
tree op0 = gimple_cond_lhs (stmt);
print_gimple_stmt (dump_file, stmt, 0, 0);
fprintf (dump_file, "\n");
}
- return;
+ return true;
}
/* Try again after inverting the condition. We only deal
print_gimple_stmt (dump_file, stmt, 0, 0);
fprintf (dump_file, "\n");
}
- return;
+ return true;
}
}
}
+
+ return false;
}
/* Simplify a switch statement using the value range of the switch
argument. */
-static void
+static bool
simplify_switch_using_ranges (gimple stmt)
{
tree op = gimple_switch_index (stmt);
switch_update su;
if (TREE_CODE (op) != SSA_NAME)
- return;
+ return false;
vr = get_value_range (op);
/* We can only handle integer ranges. */
if (vr->type != VR_RANGE
|| symbolic_range_p (vr))
- return;
+ return false;
/* Find case label for min/max of the value range. */
n = gimple_switch_num_labels (stmt);
if (i == 1
&& j == n - 1
&& take_default)
- return;
+ return false;
/* Build a new vector of taken case labels. */
vec2 = make_tree_vec (j - i + 1 + (int)take_default);
su.stmt = stmt;
su.vec = vec2;
VEC_safe_push (switch_update, heap, to_update_switch_stmts, &su);
+ return false;
}
/* Simplify STMT using ranges if possible. */
-void
-simplify_stmt_using_ranges (gimple stmt)
+bool
+simplify_stmt_using_ranges (gimple_stmt_iterator *gsi)
{
+ gimple stmt = gsi_stmt (*gsi);
if (is_gimple_assign (stmt))
{
enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
+ switch (rhs_code)
+ {
+ case EQ_EXPR:
+ case NE_EXPR:
+ case TRUTH_NOT_EXPR:
+ case TRUTH_AND_EXPR:
+ case TRUTH_OR_EXPR:
+ case TRUTH_XOR_EXPR:
+ /* Transform EQ_EXPR, NE_EXPR, TRUTH_NOT_EXPR into BIT_XOR_EXPR
+ or identity if the RHS is zero or one, and the LHS are known
+ to be boolean values. Transform all TRUTH_*_EXPR into
+ BIT_*_EXPR if both arguments are known to be boolean values. */
+ if (INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt))))
+ return simplify_truth_ops_using_ranges (gsi, stmt);
+ break;
+
/* Transform TRUNC_DIV_EXPR and TRUNC_MOD_EXPR into RSHIFT_EXPR
and BIT_AND_EXPR respectively if the first operand is greater
than zero and the second operand is an exact power of two. */
- if ((rhs_code == TRUNC_DIV_EXPR || rhs_code == TRUNC_MOD_EXPR)
- && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt)))
- && integer_pow2p (gimple_assign_rhs2 (stmt)))
- simplify_div_or_mod_using_ranges (stmt);
+ case TRUNC_DIV_EXPR:
+ case TRUNC_MOD_EXPR:
+ if (INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt)))
+ && integer_pow2p (gimple_assign_rhs2 (stmt)))
+ return simplify_div_or_mod_using_ranges (stmt);
+ break;
/* Transform ABS (X) into X or -X as appropriate. */
- if (rhs_code == ABS_EXPR
- && TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME
- && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt))))
- simplify_abs_using_ranges (stmt);
+ case ABS_EXPR:
+ if (TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME
+ && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt))))
+ return simplify_abs_using_ranges (stmt);
+ break;
+
+ default:
+ break;
+ }
}
else if (gimple_code (stmt) == GIMPLE_COND)
- simplify_cond_using_ranges (stmt);
+ return simplify_cond_using_ranges (stmt);
else if (gimple_code (stmt) == GIMPLE_SWITCH)
- simplify_switch_using_ranges (stmt);
+ return simplify_switch_using_ranges (stmt);
+
+ return false;
}
/* Stack of dest,src equivalency pairs that need to be restored after
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