/* Support routines for Value Range Propagation (VRP).
- Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
+ Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
Contributed by Diego Novillo <dnovillo@redhat.com>.
This file is part of GCC.
#include "tree-ssa-propagate.h"
#include "tree-chrec.h"
-/* Set of SSA names found during the dominator traversal of a
- sub-graph in find_assert_locations. */
-static sbitmap found_in_subgraph;
+
+/* Set of SSA names found live during the RPO traversal of the function
+ for still active basic-blocks. */
+static sbitmap *live;
+
+/* Return true if the SSA name NAME is live on the edge E. */
+
+static bool
+live_on_edge (edge e, tree name)
+{
+ return (live[e->dest->index]
+ && TEST_BIT (live[e->dest->index], SSA_NAME_VERSION (name)));
+}
/* Local functions. */
static int compare_values (tree val1, tree val2);
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 (tree, bool, bool *);
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
edge e;
/* Pointer to the statement that generated this assertion. */
- block_stmt_iterator si;
+ gimple_stmt_iterator si;
/* Predicate code for the ASSERT_EXPR. Must be COMPARISON_CLASS_P. */
enum tree_code comp_code;
ASSERT_EXPRs for SSA name N_I should be inserted. */
static assert_locus_t *asserts_for;
-/* Set of blocks visited in find_assert_locations. Used to avoid
- visiting the same block more than once. */
-static sbitmap blocks_visited;
-
/* Value range array. After propagation, VR_VALUE[I] holds the range
of values that SSA name N_I may take. */
static value_range_t **vr_value;
node. */
static int *vr_phi_edge_counts;
+typedef struct {
+ gimple stmt;
+ tree vec;
+} switch_update;
+
+static VEC (edge, heap) *to_remove_edges;
+DEF_VEC_O(switch_update);
+DEF_VEC_ALLOC_O(switch_update, heap);
+static VEC (switch_update, heap) *to_update_switch_stmts;
+
-/* Return the maximum value for TYPEs base type. */
+/* Return the maximum value for TYPE. */
static inline tree
vrp_val_max (const_tree type)
if (!INTEGRAL_TYPE_P (type))
return NULL_TREE;
- /* For integer sub-types the values for the base type are relevant. */
- if (TREE_TYPE (type))
- type = TREE_TYPE (type);
-
return TYPE_MAX_VALUE (type);
}
-/* Return the minimum value for TYPEs base type. */
+/* Return the minimum value for TYPE. */
static inline tree
vrp_val_min (const_tree type)
if (!INTEGRAL_TYPE_P (type))
return NULL_TREE;
- /* For integer sub-types the values for the base type are relevant. */
- if (TREE_TYPE (type))
- type = TREE_TYPE (type);
-
return TYPE_MIN_VALUE (type);
}
static inline bool
needs_overflow_infinity (const_tree type)
{
- return (INTEGRAL_TYPE_P (type)
- && !TYPE_OVERFLOW_WRAPS (type)
- /* Integer sub-types never overflow as they are never
- operands of arithmetic operators. */
- && !(TREE_TYPE (type) && TREE_TYPE (type) != type));
+ return INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type);
}
/* Return whether TYPE can support our overflow infinity
&& (vrp_val_is_min (val) || vrp_val_is_max (val)));
}
+/* Return whether STMT has a constant rhs that is_overflow_infinity. */
+
+static inline bool
+stmt_overflow_infinity (gimple stmt)
+{
+ if (is_gimple_assign (stmt)
+ && get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) ==
+ GIMPLE_SINGLE_RHS)
+ return is_overflow_infinity (gimple_assign_rhs1 (stmt));
+ return false;
+}
+
/* If VAL is now an overflow infinity, return VAL. Otherwise, return
the same value with TREE_OVERFLOW clear. This can be used to avoid
confusing a regular value with an overflow value. */
}
-/* Return value range information for VAR.
+/* If abs (min) < abs (max), set VR to [-max, max], if
+ abs (min) >= abs (max), set VR to [-min, min]. */
+
+static void
+abs_extent_range (value_range_t *vr, tree min, tree max)
+{
+ int cmp;
+
+ gcc_assert (TREE_CODE (min) == INTEGER_CST);
+ gcc_assert (TREE_CODE (max) == INTEGER_CST);
+ gcc_assert (INTEGRAL_TYPE_P (TREE_TYPE (min)));
+ gcc_assert (!TYPE_UNSIGNED (TREE_TYPE (min)));
+ min = fold_unary (ABS_EXPR, TREE_TYPE (min), min);
+ max = fold_unary (ABS_EXPR, TREE_TYPE (max), max);
+ if (TREE_OVERFLOW (min) || TREE_OVERFLOW (max))
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
+ cmp = compare_values (min, max);
+ if (cmp == -1)
+ min = fold_unary (NEGATE_EXPR, TREE_TYPE (min), max);
+ else if (cmp == 0 || cmp == 1)
+ {
+ max = min;
+ min = fold_unary (NEGATE_EXPR, TREE_TYPE (min), min);
+ }
+ else
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
+ set_and_canonicalize_value_range (vr, VR_RANGE, min, max, NULL);
+}
+
+
+/* Return value range information for VAR.
If we have no values ranges recorded (ie, VRP is not running), then
return NULL. Otherwise create an empty range if none existed for VAR. */
&& integer_zerop (vr->max);
}
+/* Return true if max and min of VR are INTEGER_CST. It's not necessary
+ a singleton. */
+
+static inline bool
+range_int_cst_p (value_range_t *vr)
+{
+ return (vr->type == VR_RANGE
+ && TREE_CODE (vr->max) == INTEGER_CST
+ && TREE_CODE (vr->min) == INTEGER_CST
+ && !TREE_OVERFLOW (vr->max)
+ && !TREE_OVERFLOW (vr->min));
+}
+
+/* Return true if VR is a INTEGER_CST singleton. */
+
+static inline bool
+range_int_cst_singleton_p (value_range_t *vr)
+{
+ return (range_int_cst_p (vr)
+ && tree_int_cst_equal (vr->min, vr->max));
+}
/* Return true if value range VR involves at least one symbol. */
static bool
vrp_expr_computes_nonnegative (tree expr, bool *strict_overflow_p)
{
- return tree_expr_nonnegative_warnv_p (expr, strict_overflow_p);
+ return (tree_expr_nonnegative_warnv_p (expr, strict_overflow_p)
+ || (TREE_CODE (expr) == SSA_NAME
+ && ssa_name_nonnegative_p (expr)));
+}
+
+/* Return true if the result of assignment STMT is know to be non-negative.
+ If the return value is based on the assumption that signed overflow is
+ undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't change
+ *STRICT_OVERFLOW_P.*/
+
+static bool
+gimple_assign_nonnegative_warnv_p (gimple stmt, bool *strict_overflow_p)
+{
+ enum tree_code code = gimple_assign_rhs_code (stmt);
+ switch (get_gimple_rhs_class (code))
+ {
+ case GIMPLE_UNARY_RHS:
+ return tree_unary_nonnegative_warnv_p (gimple_assign_rhs_code (stmt),
+ gimple_expr_type (stmt),
+ gimple_assign_rhs1 (stmt),
+ strict_overflow_p);
+ case GIMPLE_BINARY_RHS:
+ return tree_binary_nonnegative_warnv_p (gimple_assign_rhs_code (stmt),
+ gimple_expr_type (stmt),
+ gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt),
+ strict_overflow_p);
+ case GIMPLE_SINGLE_RHS:
+ return tree_single_nonnegative_warnv_p (gimple_assign_rhs1 (stmt),
+ strict_overflow_p);
+ case GIMPLE_INVALID_RHS:
+ gcc_unreachable ();
+ default:
+ gcc_unreachable ();
+ }
+}
+
+/* Return true if return value of call STMT is know to be non-negative.
+ If the return value is based on the assumption that signed overflow is
+ undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't change
+ *STRICT_OVERFLOW_P.*/
+
+static bool
+gimple_call_nonnegative_warnv_p (gimple stmt, bool *strict_overflow_p)
+{
+ tree arg0 = gimple_call_num_args (stmt) > 0 ?
+ gimple_call_arg (stmt, 0) : NULL_TREE;
+ tree arg1 = gimple_call_num_args (stmt) > 1 ?
+ gimple_call_arg (stmt, 1) : NULL_TREE;
+
+ return tree_call_nonnegative_warnv_p (gimple_expr_type (stmt),
+ gimple_call_fndecl (stmt),
+ arg0,
+ arg1,
+ strict_overflow_p);
+}
+
+/* Return true if STMT is know to to compute a non-negative value.
+ If the return value is based on the assumption that signed overflow is
+ undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't change
+ *STRICT_OVERFLOW_P.*/
+
+static bool
+gimple_stmt_nonnegative_warnv_p (gimple stmt, bool *strict_overflow_p)
+{
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_ASSIGN:
+ return gimple_assign_nonnegative_warnv_p (stmt, strict_overflow_p);
+ case GIMPLE_CALL:
+ return gimple_call_nonnegative_warnv_p (stmt, strict_overflow_p);
+ default:
+ gcc_unreachable ();
+ }
+}
+
+/* Return true if the result of assignment STMT is know to be non-zero.
+ If the return value is based on the assumption that signed overflow is
+ undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't change
+ *STRICT_OVERFLOW_P.*/
+
+static bool
+gimple_assign_nonzero_warnv_p (gimple stmt, bool *strict_overflow_p)
+{
+ enum tree_code code = gimple_assign_rhs_code (stmt);
+ switch (get_gimple_rhs_class (code))
+ {
+ case GIMPLE_UNARY_RHS:
+ return tree_unary_nonzero_warnv_p (gimple_assign_rhs_code (stmt),
+ gimple_expr_type (stmt),
+ gimple_assign_rhs1 (stmt),
+ strict_overflow_p);
+ case GIMPLE_BINARY_RHS:
+ return tree_binary_nonzero_warnv_p (gimple_assign_rhs_code (stmt),
+ gimple_expr_type (stmt),
+ gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt),
+ strict_overflow_p);
+ case GIMPLE_SINGLE_RHS:
+ return tree_single_nonzero_warnv_p (gimple_assign_rhs1 (stmt),
+ strict_overflow_p);
+ case GIMPLE_INVALID_RHS:
+ gcc_unreachable ();
+ default:
+ gcc_unreachable ();
+ }
+}
+
+/* Return true if STMT is know to to compute a non-zero value.
+ If the return value is based on the assumption that signed overflow is
+ undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't change
+ *STRICT_OVERFLOW_P.*/
+
+static bool
+gimple_stmt_nonzero_warnv_p (gimple stmt, bool *strict_overflow_p)
+{
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_ASSIGN:
+ return gimple_assign_nonzero_warnv_p (stmt, strict_overflow_p);
+ case GIMPLE_CALL:
+ return gimple_alloca_call_p (stmt);
+ default:
+ gcc_unreachable ();
+ }
}
/* Like tree_expr_nonzero_warnv_p, but this function uses value ranges
obtained so far. */
static bool
-vrp_expr_computes_nonzero (tree expr, bool *strict_overflow_p)
+vrp_stmt_computes_nonzero (gimple stmt, bool *strict_overflow_p)
{
- if (tree_expr_nonzero_warnv_p (expr, strict_overflow_p))
+ if (gimple_stmt_nonzero_warnv_p (stmt, strict_overflow_p))
return true;
/* If we have an expression of the form &X->a, then the expression
is nonnull if X is nonnull. */
- if (TREE_CODE (expr) == ADDR_EXPR)
+ if (is_gimple_assign (stmt)
+ && gimple_assign_rhs_code (stmt) == ADDR_EXPR)
{
+ tree expr = gimple_assign_rhs1 (stmt);
tree base = get_base_address (TREE_OPERAND (expr, 0));
if (base != NULL_TREE
|| TREE_CODE (expr) == MINUS_EXPR)
return (TREE_CODE (TREE_OPERAND (expr, 0)) == SSA_NAME
&& TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST);
-
+
return is_gimple_min_invariant (expr);
}
-/* Return
+/* Return
1 if VAL < VAL2
0 if !(VAL < VAL2)
-2 if those are incomparable. */
}
/* Compare two values VAL1 and VAL2. Return
-
+
-2 if VAL1 and VAL2 cannot be compared at compile-time,
-1 if VAL1 < VAL2,
0 if VAL1 == VAL2,
{
tree n1, c1, n2, c2;
enum tree_code code1, code2;
-
+
/* If VAL1 and VAL2 are of the form 'NAME [+-] CST' or 'NAME',
return -1 or +1 accordingly. If VAL1 and VAL2 don't use the
same name, return -2. */
/* First see if VAL1 and VAL2 are not the same. */
if (val1 == val2 || operand_equal_p (val1, val2, 0))
return 0;
-
+
/* If VAL1 is a lower address than VAL2, return -1. */
if (operand_less_p (val1, val2) == 1)
return -1;
This also applies to value_ranges_intersect_p and
range_includes_zero_p. The semantics of VR_RANGE and
VR_ANTI_RANGE should be encoded here, but that also means
- adapting the users of these functions to the new semantics.
+ adapting the users of these functions to the new semantics.
Benchmark compile/20001226-1.c compilation time after changing this
function. */
/* Return true if value ranges VR0 and VR1 have a non-empty
- intersection.
-
+ intersection.
+
Benchmark compile/20001226-1.c compilation time after changing this
function.
*/
{
value_range_t *vr = get_value_range (t);
+ if (INTEGRAL_TYPE_P (t)
+ && TYPE_UNSIGNED (t))
+ return true;
+
if (!vr)
return false;
return false;
}
-/* Return true if T, an SSA_NAME, is known to be nonzero. Return
- false otherwise or if no value range information is available. */
+/* If OP has a value range with a single constant value return that,
+ otherwise return NULL_TREE. This returns OP itself if OP is a
+ constant. */
-bool
-ssa_name_nonzero_p (const_tree t)
+static tree
+op_with_constant_singleton_value_range (tree op)
{
- value_range_t *vr = get_value_range (t);
+ value_range_t *vr;
- if (!vr)
- return false;
+ if (is_gimple_min_invariant (op))
+ return op;
- /* A VR_RANGE which does not include zero is a nonzero value. */
- if (vr->type == VR_RANGE && !symbolic_range_p (vr))
- return ! range_includes_zero_p (vr);
+ if (TREE_CODE (op) != SSA_NAME)
+ return NULL_TREE;
- /* A VR_ANTI_RANGE which does include zero is a nonzero value. */
- if (vr->type == VR_ANTI_RANGE && !symbolic_range_p (vr))
- return range_includes_zero_p (vr);
+ vr = get_value_range (op);
+ if (vr->type == VR_RANGE
+ && operand_equal_p (vr->min, vr->max, 0)
+ && is_gimple_min_invariant (vr->min))
+ return vr->min;
- return false;
+ return NULL_TREE;
}
The only situation in which we can build a valid
anti-range is when LIMIT_VR is a single-valued range
- (i.e., LIMIT_VR->MIN == LIMIT_VR->MAX). In that case,
+ (i.e., LIMIT_VR->MIN == LIMIT_VR->MAX). In that case,
build the anti-range ~[LIMIT_VR->MIN, LIMIT_VR->MAX]. */
if (limit_vr
&& limit_vr->type == VR_RANGE
all should be optimized away above us. */
if ((cond_code == LT_EXPR
&& compare_values (max, min) == 0)
- || is_overflow_infinity (max))
+ || (CONSTANT_CLASS_P (max) && TREE_OVERFLOW (max)))
set_value_range_to_varying (vr_p);
else
{
all should be optimized away above us. */
if ((cond_code == GT_EXPR
&& compare_values (min, max) == 0)
- || is_overflow_infinity (min))
+ || (CONSTANT_CLASS_P (min) && TREE_OVERFLOW (min)))
set_value_range_to_varying (vr_p);
else
{
there are three cases to consider.
- 1. The VR_ANTI_RANGE range is completely within the
+ 1. The VR_ANTI_RANGE range is completely within the
VR_RANGE and the endpoints of the ranges are
different. In that case the resulting range
should be whichever range is more precise.
3a. If the high limit of the VR_ANTI_RANGE resides
within the VR_RANGE, then the result is a new
VR_RANGE starting at the high limit of the
- the VR_ANTI_RANGE + 1 and extending to the
+ VR_ANTI_RANGE + 1 and extending to the
high limit of the original VR_RANGE.
3b. If the low limit of the VR_ANTI_RANGE resides
res = int_const_binop (code, val1, val2, 0);
- /* If we are not using wrapping arithmetic, operate symbolically
- on -INF and +INF. */
- if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (val1)))
+ /* If we are using unsigned arithmetic, operate symbolically
+ on -INF and +INF as int_const_binop only handles signed overflow. */
+ if (TYPE_UNSIGNED (TREE_TYPE (val1)))
{
int checkz = compare_values (res, val1);
bool overflow = false;
}
}
+ else if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (val1)))
+ /* If the singed operation wraps then int_const_binop has done
+ everything we want. */
+ ;
else if ((TREE_OVERFLOW (res)
&& !TREE_OVERFLOW (val1)
&& !TREE_OVERFLOW (val2))
&& code != CEIL_DIV_EXPR
&& code != EXACT_DIV_EXPR
&& code != ROUND_DIV_EXPR
+ && code != TRUNC_MOD_EXPR
+ && code != FLOOR_MOD_EXPR
+ && code != CEIL_MOD_EXPR
+ && code != ROUND_MOD_EXPR
&& code != RSHIFT_EXPR
&& code != MIN_EXPR
&& code != MAX_EXPR
&& code != BIT_AND_EXPR
- && code != TRUTH_ANDIF_EXPR
- && code != TRUTH_ORIF_EXPR
+ && code != BIT_IOR_EXPR
&& code != TRUTH_AND_EXPR
&& code != TRUTH_OR_EXPR)
{
+ /* We can still do constant propagation here. */
+ 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,
+ 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;
+ }
+ }
set_value_range_to_varying (vr);
return;
}
/* Refuse to operate on VARYING ranges, ranges of different kinds
and symbolic ranges. As an exception, we allow BIT_AND_EXPR
because we may be able to derive a useful range even if one of
- the operands is VR_VARYING or symbolic range. TODO, we may be
- able to derive anti-ranges in some cases. */
+ the operands is VR_VARYING or symbolic range. Similarly for
+ divisions. TODO, we may be able to derive anti-ranges in
+ some cases. */
if (code != BIT_AND_EXPR
&& code != TRUTH_AND_EXPR
&& code != TRUTH_OR_EXPR
+ && code != TRUNC_DIV_EXPR
+ && code != FLOOR_DIV_EXPR
+ && code != CEIL_DIV_EXPR
+ && code != EXACT_DIV_EXPR
+ && code != ROUND_DIV_EXPR
+ && code != TRUNC_MOD_EXPR
+ && code != FLOOR_MOD_EXPR
+ && code != CEIL_MOD_EXPR
+ && code != ROUND_MOD_EXPR
&& (vr0.type == VR_VARYING
|| vr1.type == VR_VARYING
|| vr0.type != vr1.type
/* For integer ranges, apply the operation to each end of the
range and see what we end up with. */
- if (code == TRUTH_ANDIF_EXPR
- || code == TRUTH_ORIF_EXPR
- || code == TRUTH_AND_EXPR
+ if (code == TRUTH_AND_EXPR
|| code == TRUTH_OR_EXPR)
{
/* If one of the operands is zero, we know that the whole
the same end of each range. */
min = vrp_int_const_binop (code, vr0.min, vr1.min);
max = vrp_int_const_binop (code, vr0.max, vr1.max);
+
+ /* If both additions overflowed the range kind is still correct.
+ This happens regularly with subtracting something in unsigned
+ arithmetic.
+ ??? See PR30318 for all the cases we do not handle. */
+ if (code == PLUS_EXPR
+ && (TREE_OVERFLOW (min) && !is_overflow_infinity (min))
+ && (TREE_OVERFLOW (max) && !is_overflow_infinity (max)))
+ {
+ min = build_int_cst_wide (TREE_TYPE (min),
+ TREE_INT_CST_LOW (min),
+ TREE_INT_CST_HIGH (min));
+ max = build_int_cst_wide (TREE_TYPE (max),
+ TREE_INT_CST_LOW (max),
+ TREE_INT_CST_HIGH (max));
+ }
}
else if (code == MULT_EXPR
|| code == TRUNC_DIV_EXPR
}
}
+ else if ((code == TRUNC_DIV_EXPR
+ || code == FLOOR_DIV_EXPR
+ || code == CEIL_DIV_EXPR
+ || code == EXACT_DIV_EXPR
+ || code == ROUND_DIV_EXPR)
+ && (vr0.type != VR_RANGE || symbolic_range_p (&vr0)))
+ {
+ /* For division, if op1 has VR_RANGE but op0 does not, something
+ can be deduced just from that range. Say [min, max] / [4, max]
+ gives [min / 4, max / 4] range. */
+ if (vr1.type == VR_RANGE
+ && !symbolic_range_p (&vr1)
+ && !range_includes_zero_p (&vr1))
+ {
+ vr0.type = type = VR_RANGE;
+ vr0.min = vrp_val_min (TREE_TYPE (op0));
+ vr0.max = vrp_val_max (TREE_TYPE (op1));
+ }
+ else
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
+ }
+
+ /* For divisions, if op0 is VR_RANGE, we can deduce a range
+ even if op1 is VR_VARYING, VR_ANTI_RANGE, symbolic or can
+ include 0. */
+ if ((code == TRUNC_DIV_EXPR
+ || code == FLOOR_DIV_EXPR
+ || code == CEIL_DIV_EXPR
+ || code == EXACT_DIV_EXPR
+ || code == ROUND_DIV_EXPR)
+ && vr0.type == VR_RANGE
+ && (vr1.type != VR_RANGE
+ || symbolic_range_p (&vr1)
+ || range_includes_zero_p (&vr1)))
+ {
+ tree zero = build_int_cst (TREE_TYPE (vr0.min), 0);
+ int cmp;
+
+ sop = false;
+ min = NULL_TREE;
+ max = NULL_TREE;
+ if (vrp_expr_computes_nonnegative (op1, &sop) && !sop)
+ {
+ /* For unsigned division or when divisor is known
+ to be non-negative, the range has to cover
+ all numbers from 0 to max for positive max
+ and all numbers from min to 0 for negative min. */
+ cmp = compare_values (vr0.max, zero);
+ if (cmp == -1)
+ max = zero;
+ else if (cmp == 0 || cmp == 1)
+ max = vr0.max;
+ else
+ type = VR_VARYING;
+ cmp = compare_values (vr0.min, zero);
+ if (cmp == 1)
+ min = zero;
+ else if (cmp == 0 || cmp == -1)
+ min = vr0.min;
+ else
+ type = VR_VARYING;
+ }
+ else
+ {
+ /* Otherwise the range is -max .. max or min .. -min
+ depending on which bound is bigger in absolute value,
+ as the division can change the sign. */
+ abs_extent_range (vr, vr0.min, vr0.max);
+ return;
+ }
+ if (type == VR_VARYING)
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
+ }
+
/* Multiplications and divisions are a bit tricky to handle,
depending on the mix of signs we have in the two ranges, we
need to operate on different values to get the minimum and
(MIN0 OP MIN1, MIN0 OP MAX1, MAX0 OP MIN1 and MAX0 OP MAX0 OP
MAX1) and then figure the smallest and largest values to form
the new range. */
-
- /* Divisions by zero result in a VARYING value. */
- else if (code != MULT_EXPR
- && (vr0.type == VR_ANTI_RANGE || range_includes_zero_p (&vr1)))
- {
- set_value_range_to_varying (vr);
- return;
- }
-
- /* Compute the 4 cross operations. */
- sop = false;
- val[0] = vrp_int_const_binop (code, vr0.min, vr1.min);
- if (val[0] == NULL_TREE)
- sop = true;
-
- if (vr1.max == vr1.min)
- val[1] = NULL_TREE;
else
{
- val[1] = vrp_int_const_binop (code, vr0.min, vr1.max);
- if (val[1] == NULL_TREE)
- sop = true;
- }
+ gcc_assert ((vr0.type == VR_RANGE
+ || (code == MULT_EXPR && vr0.type == VR_ANTI_RANGE))
+ && vr0.type == vr1.type);
- if (vr0.max == vr0.min)
- val[2] = NULL_TREE;
- else
- {
- val[2] = vrp_int_const_binop (code, vr0.max, vr1.min);
- if (val[2] == NULL_TREE)
+ /* Compute the 4 cross operations. */
+ sop = false;
+ val[0] = vrp_int_const_binop (code, vr0.min, vr1.min);
+ if (val[0] == NULL_TREE)
sop = true;
- }
- if (vr0.min == vr0.max || vr1.min == vr1.max)
- val[3] = NULL_TREE;
- else
- {
- val[3] = vrp_int_const_binop (code, vr0.max, vr1.max);
- if (val[3] == NULL_TREE)
- sop = true;
- }
+ if (vr1.max == vr1.min)
+ val[1] = NULL_TREE;
+ else
+ {
+ val[1] = vrp_int_const_binop (code, vr0.min, vr1.max);
+ if (val[1] == NULL_TREE)
+ sop = true;
+ }
- if (sop)
- {
- set_value_range_to_varying (vr);
- return;
- }
+ if (vr0.max == vr0.min)
+ val[2] = NULL_TREE;
+ else
+ {
+ val[2] = vrp_int_const_binop (code, vr0.max, vr1.min);
+ if (val[2] == NULL_TREE)
+ sop = true;
+ }
- /* Set MIN to the minimum of VAL[i] and MAX to the maximum
- of VAL[i]. */
- min = val[0];
- max = val[0];
- for (i = 1; i < 4; i++)
- {
- if (!is_gimple_min_invariant (min)
- || (TREE_OVERFLOW (min) && !is_overflow_infinity (min))
- || !is_gimple_min_invariant (max)
- || (TREE_OVERFLOW (max) && !is_overflow_infinity (max)))
- break;
+ if (vr0.min == vr0.max || vr1.min == vr1.max)
+ val[3] = NULL_TREE;
+ else
+ {
+ val[3] = vrp_int_const_binop (code, vr0.max, vr1.max);
+ if (val[3] == NULL_TREE)
+ sop = true;
+ }
+
+ if (sop)
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
- if (val[i])
+ /* Set MIN to the minimum of VAL[i] and MAX to the maximum
+ of VAL[i]. */
+ min = val[0];
+ max = val[0];
+ for (i = 1; i < 4; i++)
{
- if (!is_gimple_min_invariant (val[i])
- || (TREE_OVERFLOW (val[i])
- && !is_overflow_infinity (val[i])))
+ if (!is_gimple_min_invariant (min)
+ || (TREE_OVERFLOW (min) && !is_overflow_infinity (min))
+ || !is_gimple_min_invariant (max)
+ || (TREE_OVERFLOW (max) && !is_overflow_infinity (max)))
+ break;
+
+ if (val[i])
{
- /* If we found an overflowed value, set MIN and MAX
- to it so that we set the resulting range to
- VARYING. */
- min = max = val[i];
- break;
- }
+ if (!is_gimple_min_invariant (val[i])
+ || (TREE_OVERFLOW (val[i])
+ && !is_overflow_infinity (val[i])))
+ {
+ /* If we found an overflowed value, set MIN and MAX
+ to it so that we set the resulting range to
+ VARYING. */
+ min = max = val[i];
+ break;
+ }
- if (compare_values (val[i], min) == -1)
- min = val[i];
+ if (compare_values (val[i], min) == -1)
+ min = val[i];
- if (compare_values (val[i], max) == 1)
- max = val[i];
+ if (compare_values (val[i], max) == 1)
+ max = val[i];
+ }
}
}
}
+ else if (code == TRUNC_MOD_EXPR
+ || code == FLOOR_MOD_EXPR
+ || code == CEIL_MOD_EXPR
+ || code == ROUND_MOD_EXPR)
+ {
+ bool sop = false;
+ if (vr0.type == VR_ANTI_RANGE
+ || vr1.type != VR_RANGE
+ || symbolic_range_p (&vr1)
+ || range_includes_zero_p (&vr1))
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
+ type = VR_RANGE;
+ max = int_const_binop (MINUS_EXPR, vr1.max, integer_one_node, 0);
+ if (vrp_expr_computes_nonnegative (op0, &sop)
+ && vrp_expr_computes_nonnegative (op1, &sop) && !sop)
+ min = build_int_cst (TREE_TYPE (vr1.max), 0);
+ else
+ min = fold_unary (NEGATE_EXPR, TREE_TYPE (max), max);
+ }
else if (code == MINUS_EXPR)
{
/* If we have a MINUS_EXPR with two VR_ANTI_RANGEs, drop to
}
else if (code == BIT_AND_EXPR)
{
- if (vr0.type == VR_RANGE
- && vr0.min == vr0.max
- && TREE_CODE (vr0.max) == INTEGER_CST
- && !TREE_OVERFLOW (vr0.max)
- && tree_int_cst_sgn (vr0.max) >= 0)
+ bool vr0_int_cst_singleton_p, vr1_int_cst_singleton_p;
+
+ vr0_int_cst_singleton_p = range_int_cst_singleton_p (&vr0);
+ vr1_int_cst_singleton_p = range_int_cst_singleton_p (&vr1);
+
+ if (vr0_int_cst_singleton_p && vr1_int_cst_singleton_p)
+ min = max = int_const_binop (code, vr0.max, vr1.max, 0);
+ else if (vr0_int_cst_singleton_p
+ && tree_int_cst_sgn (vr0.max) >= 0)
{
min = build_int_cst (expr_type, 0);
max = vr0.max;
}
- else if (vr1.type == VR_RANGE
- && vr1.min == vr1.max
- && TREE_CODE (vr1.max) == INTEGER_CST
- && !TREE_OVERFLOW (vr1.max)
+ else if (vr1_int_cst_singleton_p
&& tree_int_cst_sgn (vr1.max) >= 0)
{
type = VR_RANGE;
return;
}
}
+ else if (code == BIT_IOR_EXPR)
+ {
+ if (range_int_cst_p (&vr0)
+ && range_int_cst_p (&vr1)
+ && 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 = ~(unsigned HOST_WIDE_INT)0u;
+ ior_max.high |= ((HOST_WIDE_INT) 1
+ << floor_log2 (ior_max.high)) - 1;
+ }
+ else if (ior_max.low != 0)
+ 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 (code == FIX_TRUNC_EXPR
|| code == FLOAT_EXPR
|| code == BIT_NOT_EXPR
- || code == NON_LVALUE_EXPR
|| code == CONJ_EXPR)
{
+ /* We can still do constant propagation here. */
+ if ((op0 = op_with_constant_singleton_value_range (op0)) != NULL_TREE)
+ {
+ tree tem = fold_unary (code, type, op0);
+ if (tem
+ && is_gimple_min_invariant (tem)
+ && !is_overflow_infinity (tem))
+ {
+ set_value_range (vr, VR_RANGE, tem, tem, NULL);
+ return;
+ }
+ }
set_value_range_to_varying (vr);
return;
}
}
/* Handle unary expressions on integer ranges. */
- if (code == NOP_EXPR || code == CONVERT_EXPR)
+ if (CONVERT_EXPR_CODE_P (code)
+ && INTEGRAL_TYPE_P (type)
+ && INTEGRAL_TYPE_P (TREE_TYPE (op0)))
{
tree inner_type = TREE_TYPE (op0);
tree outer_type = type;
- /* If VR0 represents a simple range, then try to convert
- the min and max values for the range to the same type
- as OUTER_TYPE. If the results compare equal to VR0's
- min and max values and the new min is still less than
- or equal to the new max, then we can safely use the newly
- computed range for EXPR. This allows us to compute
- accurate ranges through many casts. */
- if ((vr0.type == VR_RANGE
- && !overflow_infinity_range_p (&vr0))
- || (vr0.type == VR_VARYING
- && TYPE_PRECISION (outer_type) > TYPE_PRECISION (inner_type)))
+ /* If VR0 is varying and we increase the type precision, assume
+ a full range for the following transformation. */
+ if (vr0.type == VR_VARYING
+ && TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type))
{
- tree new_min, new_max, orig_min, orig_max;
-
- /* Convert the input operand min/max to OUTER_TYPE. If
- the input has no range information, then use the min/max
- for the input's type. */
- if (vr0.type == VR_RANGE)
- {
- orig_min = vr0.min;
- orig_max = vr0.max;
- }
- else
- {
- orig_min = TYPE_MIN_VALUE (inner_type);
- orig_max = TYPE_MAX_VALUE (inner_type);
- }
-
- new_min = fold_convert (outer_type, orig_min);
- new_max = fold_convert (outer_type, orig_max);
-
- /* Verify the new min/max values are gimple values and
- that they compare equal to the original input's
- min/max values. */
- if (is_gimple_val (new_min)
- && is_gimple_val (new_max)
- && tree_int_cst_equal (new_min, orig_min)
- && tree_int_cst_equal (new_max, orig_max)
- && (!is_overflow_infinity (new_min)
- || !is_overflow_infinity (new_max))
- && (cmp = compare_values (new_min, new_max)) <= 0
- && cmp >= -1)
- {
- set_value_range (vr, VR_RANGE, new_min, new_max, vr->equiv);
- return;
- }
+ vr0.type = VR_RANGE;
+ vr0.min = TYPE_MIN_VALUE (inner_type);
+ vr0.max = TYPE_MAX_VALUE (inner_type);
}
- /* When converting types of different sizes, set the result to
- VARYING. Things like sign extensions and precision loss may
- change the range. For instance, if x_3 is of type 'long long
- int' and 'y_5 = (unsigned short) x_3', if x_3 is ~[0, 0], it
- is impossible to know at compile time whether y_5 will be
- ~[0, 0]. */
- if (TYPE_SIZE (inner_type) != TYPE_SIZE (outer_type)
- || TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
+ /* If VR0 is a constant range or anti-range and the conversion is
+ not truncating we can convert the min and max values and
+ canonicalize the resulting range. Otherwise we can do the
+ conversion if the size of the range is less than what the
+ precision of the target type can represent and the range is
+ not an anti-range. */
+ if ((vr0.type == VR_RANGE
+ || vr0.type == VR_ANTI_RANGE)
+ && TREE_CODE (vr0.min) == INTEGER_CST
+ && TREE_CODE (vr0.max) == INTEGER_CST
+ && (!is_overflow_infinity (vr0.min)
+ || (vr0.type == VR_RANGE
+ && TYPE_PRECISION (outer_type) > TYPE_PRECISION (inner_type)
+ && needs_overflow_infinity (outer_type)
+ && supports_overflow_infinity (outer_type)))
+ && (!is_overflow_infinity (vr0.max)
+ || (vr0.type == VR_RANGE
+ && TYPE_PRECISION (outer_type) > TYPE_PRECISION (inner_type)
+ && needs_overflow_infinity (outer_type)
+ && supports_overflow_infinity (outer_type)))
+ && (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
+ || (vr0.type == VR_RANGE
+ && integer_zerop (int_const_binop (RSHIFT_EXPR,
+ int_const_binop (MINUS_EXPR, vr0.max, vr0.min, 0),
+ size_int (TYPE_PRECISION (outer_type)), 0)))))
{
- set_value_range_to_varying (vr);
+ tree new_min, new_max;
+ new_min = force_fit_type_double (outer_type,
+ TREE_INT_CST_LOW (vr0.min),
+ TREE_INT_CST_HIGH (vr0.min), 0, 0);
+ new_max = force_fit_type_double (outer_type,
+ TREE_INT_CST_LOW (vr0.max),
+ TREE_INT_CST_HIGH (vr0.max), 0, 0);
+ if (is_overflow_infinity (vr0.min))
+ new_min = negative_overflow_infinity (outer_type);
+ if (is_overflow_infinity (vr0.max))
+ new_max = positive_overflow_infinity (outer_type);
+ set_and_canonicalize_value_range (vr, vr0.type,
+ new_min, new_max, NULL);
return;
}
+
+ set_value_range_to_varying (vr);
+ return;
}
/* Conversion of a VR_VARYING value to a wider type can result
set_value_range_to_varying (vr);
return;
}
-
+
/* ABS_EXPR may flip the range around, if the original range
included negative values. */
if (is_overflow_infinity (vr0.min))
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
{
/* If a VR_ANTI_RANGEs contains zero, then we have
~[-INF, min(MIN, MAX)]. */
if (vr0.type == VR_ANTI_RANGE)
- {
+ {
if (range_includes_zero_p (&vr0))
{
/* Take the lower of the two values. */
tree type, tree op0, tree op1)
{
bool sop = false;
- tree val = vrp_evaluate_conditional_warnv_with_ops (code,
- op0,
- op1,
- false, &sop);
+ tree val;
+
+ 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
set_value_range_to_truthvalue (vr, type);
}
-
-/* Try to compute a useful range out of expression EXPR and store it
- in *VR. */
+/* Try to derive a nonnegative or nonzero range out of STMT relying
+ primarily on generic routines in fold in conjunction with range data.
+ Store the result in *VR */
static void
-extract_range_from_expr (value_range_t *vr, tree expr)
+extract_range_basic (value_range_t *vr, gimple stmt)
{
- enum tree_code code = TREE_CODE (expr);
-
+ bool sop = false;
+ tree type = gimple_expr_type (stmt);
+
+ if (INTEGRAL_TYPE_P (type)
+ && gimple_stmt_nonnegative_warnv_p (stmt, &sop))
+ set_value_range_to_nonnegative (vr, type,
+ sop || stmt_overflow_infinity (stmt));
+ else if (vrp_stmt_computes_nonzero (stmt, &sop)
+ && !sop)
+ set_value_range_to_nonnull (vr, type);
+ else
+ set_value_range_to_varying (vr);
+}
+
+
+/* Try to compute a useful range out of assignment STMT and store it
+ in *VR. */
+
+static void
+extract_range_from_assignment (value_range_t *vr, gimple stmt)
+{
+ enum tree_code code = gimple_assign_rhs_code (stmt);
+
if (code == ASSERT_EXPR)
- extract_range_from_assert (vr, expr);
+ extract_range_from_assert (vr, gimple_assign_rhs1 (stmt));
else if (code == SSA_NAME)
- extract_range_from_ssa_name (vr, expr);
+ extract_range_from_ssa_name (vr, gimple_assign_rhs1 (stmt));
else if (TREE_CODE_CLASS (code) == tcc_binary
- || code == TRUTH_ANDIF_EXPR
- || code == TRUTH_ORIF_EXPR
|| code == TRUTH_AND_EXPR
|| code == TRUTH_OR_EXPR
|| code == TRUTH_XOR_EXPR)
- extract_range_from_binary_expr (vr, TREE_CODE (expr), TREE_TYPE (expr),
- TREE_OPERAND (expr, 0),
- TREE_OPERAND (expr, 1));
+ extract_range_from_binary_expr (vr, gimple_assign_rhs_code (stmt),
+ gimple_expr_type (stmt),
+ gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt));
else if (TREE_CODE_CLASS (code) == tcc_unary)
- extract_range_from_unary_expr (vr, TREE_CODE (expr), TREE_TYPE (expr),
- TREE_OPERAND (expr, 0));
+ extract_range_from_unary_expr (vr, gimple_assign_rhs_code (stmt),
+ gimple_expr_type (stmt),
+ gimple_assign_rhs1 (stmt));
else if (code == COND_EXPR)
- extract_range_from_cond_expr (vr, expr);
+ extract_range_from_cond_expr (vr, gimple_assign_rhs1 (stmt));
else if (TREE_CODE_CLASS (code) == tcc_comparison)
- extract_range_from_comparison (vr, TREE_CODE (expr), TREE_TYPE (expr),
- TREE_OPERAND (expr, 0),
- TREE_OPERAND (expr, 1));
- else if (is_gimple_min_invariant (expr))
- set_value_range_to_value (vr, expr, NULL);
+ extract_range_from_comparison (vr, gimple_assign_rhs_code (stmt),
+ gimple_expr_type (stmt),
+ gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt));
+ else if (get_gimple_rhs_class (code) == GIMPLE_SINGLE_RHS
+ && is_gimple_min_invariant (gimple_assign_rhs1 (stmt)))
+ set_value_range_to_value (vr, gimple_assign_rhs1 (stmt), NULL);
else
set_value_range_to_varying (vr);
- /* If we got a varying range from the tests above, try a final
- time to derive a nonnegative or nonzero range. This time
- relying primarily on generic routines in fold in conjunction
- with range data. */
if (vr->type == VR_VARYING)
- {
- bool sop = false;
-
- if (INTEGRAL_TYPE_P (TREE_TYPE (expr))
- && vrp_expr_computes_nonnegative (expr, &sop))
- set_value_range_to_nonnegative (vr, TREE_TYPE (expr),
- sop || is_overflow_infinity (expr));
- else if (vrp_expr_computes_nonzero (expr, &sop)
- && !sop)
- set_value_range_to_nonnull (vr, TREE_TYPE (expr));
- }
+ extract_range_basic (vr, stmt);
}
/* Given a range VR, a LOOP and a variable VAR, determine whether it
for VAR. If so, update VR with the new limits. */
static void
-adjust_range_with_scev (value_range_t *vr, struct loop *loop, tree stmt,
- tree var)
+adjust_range_with_scev (value_range_t *vr, struct loop *loop,
+ gimple stmt, tree var)
{
- tree init, step, chrec, tmin, tmax, min, max, type;
+ tree init, step, chrec, tmin, tmax, min, max, type, tem;
enum ev_direction dir;
/* TODO. Don't adjust anti-ranges. An anti-range may provide
if (vr->type == VR_ANTI_RANGE)
return;
- /* Ensure that there are not values in the scev cache based on assumptions
- on ranges of ssa names that were changed
- (in set_value_range/set_value_range_to_varying). Preserve cached numbers
- of iterations, that were computed before the start of VRP (we do not
- recompute these each time to save the compile time). */
- scev_reset_except_niters ();
-
chrec = instantiate_parameters (loop, analyze_scalar_evolution (loop, var));
/* Like in PR19590, scev can return a constant function. */
return;
init = initial_condition_in_loop_num (chrec, loop->num);
+ tem = op_with_constant_singleton_value_range (init);
+ if (tem)
+ init = tem;
step = evolution_part_in_loop_num (chrec, loop->num);
+ tem = op_with_constant_singleton_value_range (step);
+ if (tem)
+ step = tem;
/* If STEP is symbolic, we can't know whether INIT will be the
minimum or maximum value in the range. Also, unless INIT is
overflow. */
static bool
-vrp_var_may_overflow (tree var, tree stmt)
+vrp_var_may_overflow (tree var, gimple stmt)
{
struct loop *l;
tree chrec, init, step;
return true;
l = loop_containing_stmt (stmt);
- if (l == NULL)
+ if (l == NULL
+ || !loop_outer (l))
return true;
chrec = instantiate_parameters (l, analyze_scalar_evolution (l, var));
/* Given two numeric value ranges VR0, VR1 and a comparison code COMP:
-
+
- Return BOOLEAN_TRUE_NODE if VR0 COMP VR1 always returns true for
all the values in the ranges.
/* Otherwise, we don't know. */
return NULL_TREE;
}
-
+
gcc_unreachable ();
}
create a new SSA name N and return the assertion assignment
'V = ASSERT_EXPR <V, V OP W>'. */
-static tree
+static gimple
build_assert_expr_for (tree cond, tree v)
{
- tree n, assertion;
+ tree n;
+ gimple assertion;
gcc_assert (TREE_CODE (v) == SSA_NAME);
- n = duplicate_ssa_name (v, NULL_TREE);
+ n = duplicate_ssa_name (v, NULL);
if (COMPARISON_CLASS_P (cond))
{
- tree a = build2 (ASSERT_EXPR, TREE_TYPE (v), v, cond);
- assertion = build_gimple_modify_stmt (n, a);
+ tree a = build2 (ASSERT_EXPR, TREE_TYPE (v), v, cond);
+ assertion = gimple_build_assign (n, a);
}
else if (TREE_CODE (cond) == TRUTH_NOT_EXPR)
{
/* Given !V, build the assignment N = false. */
tree op0 = TREE_OPERAND (cond, 0);
gcc_assert (op0 == v);
- assertion = build_gimple_modify_stmt (n, boolean_false_node);
+ assertion = gimple_build_assign (n, boolean_false_node);
}
else if (TREE_CODE (cond) == SSA_NAME)
{
/* Given V, build the assignment N = true. */
gcc_assert (v == cond);
- assertion = build_gimple_modify_stmt (n, boolean_true_node);
+ assertion = gimple_build_assign (n, boolean_true_node);
}
else
gcc_unreachable ();
point values. */
static inline bool
-fp_predicate (const_tree expr)
+fp_predicate (gimple stmt)
{
- return (COMPARISON_CLASS_P (expr)
- && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 0))));
+ GIMPLE_CHECK (stmt, GIMPLE_COND);
+
+ return FLOAT_TYPE_P (TREE_TYPE (gimple_cond_lhs (stmt)));
}
inferred. */
static bool
-infer_value_range (tree stmt, tree op, enum tree_code *comp_code_p, tree *val_p)
+infer_value_range (gimple stmt, tree op, enum tree_code *comp_code_p, tree *val_p)
{
*val_p = NULL_TREE;
*comp_code_p = ERROR_MARK;
/* Similarly, don't infer anything from statements that may throw
exceptions. */
- if (tree_could_throw_p (stmt))
+ if (stmt_could_throw_p (stmt))
return false;
/* If STMT is the last statement of a basic block with no
successors, there is no point inferring anything about any of its
operands. We would not be able to find a proper insertion point
for the assertion, anyway. */
- if (stmt_ends_bb_p (stmt) && EDGE_COUNT (bb_for_stmt (stmt)->succs) == 0)
+ if (stmt_ends_bb_p (stmt) && EDGE_COUNT (gimple_bb (stmt)->succs) == 0)
return false;
/* We can only assume that a pointer dereference will yield
non-NULL if -fdelete-null-pointer-checks is enabled. */
- if (flag_delete_null_pointer_checks && POINTER_TYPE_P (TREE_TYPE (op)))
+ if (flag_delete_null_pointer_checks
+ && POINTER_TYPE_P (TREE_TYPE (op))
+ && gimple_code (stmt) != GIMPLE_ASM)
{
unsigned num_uses, num_loads, num_stores;
while (loc)
{
fprintf (file, "\t");
- print_generic_expr (file, bsi_stmt (loc->si), 0);
+ print_gimple_stmt (file, gsi_stmt (loc->si), 0, 0);
fprintf (file, "\n\tBB #%d", loc->bb->index);
if (loc->e)
{
tree val,
basic_block bb,
edge e,
- block_stmt_iterator si)
+ gimple_stmt_iterator si)
{
assert_locus_t n, loc, last_loc;
- bool found;
basic_block dest_bb;
#if defined ENABLE_CHECKING
gcc_assert (bb == NULL || e == NULL);
if (e == NULL)
- gcc_assert (TREE_CODE (bsi_stmt (si)) != COND_EXPR
- && TREE_CODE (bsi_stmt (si)) != SWITCH_EXPR);
+ gcc_assert (gimple_code (gsi_stmt (si)) != GIMPLE_COND
+ && 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,
assume that A will be inserted at E->DEST. Note that this is not
necessarily true.
-
+
If E is a critical edge, it will be split. But even if E is
split, the new block will dominate the same set of blocks that
E->DEST dominates.
-
+
The reverse, however, is not true, blocks dominated by E->DEST
will not be dominated by the new block created to split E. So,
if the insertion location is on a critical edge, we will not use
COMP_CODE and VAL could be implemented. */
loc = asserts_for[SSA_NAME_VERSION (name)];
last_loc = loc;
- found = false;
while (loc)
{
if (loc->comp_code == comp_code
Return true if an assertion for NAME could be registered. */
static bool
-register_edge_assert_for_2 (tree name, edge e, block_stmt_iterator bsi,
+register_edge_assert_for_2 (tree name, edge e, gimple_stmt_iterator bsi,
enum tree_code cond_code,
tree cond_op0, tree cond_op1, bool invert)
{
/* Only register an ASSERT_EXPR if NAME was found in the sub-graph
reachable from E. */
- if (TEST_BIT (found_in_subgraph, SSA_NAME_VERSION (name))
+ if (live_on_edge (e, name)
&& !has_single_use (name))
{
register_new_assert_for (name, name, comp_code, val, NULL, e, bsi);
&& TREE_CODE (val) == INTEGER_CST
&& TYPE_UNSIGNED (TREE_TYPE (val)))
{
- tree def_stmt = SSA_NAME_DEF_STMT (name);
+ gimple def_stmt = SSA_NAME_DEF_STMT (name);
tree cst2 = NULL_TREE, name2 = NULL_TREE, name3 = NULL_TREE;
/* Extract CST2 from the (optional) addition. */
- if (TREE_CODE (def_stmt) == GIMPLE_MODIFY_STMT
- && TREE_CODE (GIMPLE_STMT_OPERAND (def_stmt, 1)) == PLUS_EXPR)
+ if (is_gimple_assign (def_stmt)
+ && gimple_assign_rhs_code (def_stmt) == PLUS_EXPR)
{
- name2 = TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1), 0);
- cst2 = TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1), 1);
+ name2 = gimple_assign_rhs1 (def_stmt);
+ cst2 = gimple_assign_rhs2 (def_stmt);
if (TREE_CODE (name2) == SSA_NAME
&& TREE_CODE (cst2) == INTEGER_CST)
def_stmt = SSA_NAME_DEF_STMT (name2);
}
/* Extract NAME2 from the (optional) sign-changing cast. */
- if (TREE_CODE (def_stmt) == GIMPLE_MODIFY_STMT
- && (TREE_CODE (GIMPLE_STMT_OPERAND (def_stmt, 1)) == NOP_EXPR
- || TREE_CODE (GIMPLE_STMT_OPERAND (def_stmt, 1)) == CONVERT_EXPR))
+ if (gimple_assign_cast_p (def_stmt))
{
- tree rhs = GIMPLE_STMT_OPERAND (def_stmt, 1);
- if ((TREE_CODE (rhs) == NOP_EXPR
- || TREE_CODE (rhs) == CONVERT_EXPR)
- && ! TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (rhs, 0)))
- && (TYPE_PRECISION (TREE_TYPE (rhs))
- == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (rhs, 0)))))
- name3 = TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1), 0);
+ if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt))
+ && ! TYPE_UNSIGNED (TREE_TYPE (gimple_assign_rhs1 (def_stmt)))
+ && (TYPE_PRECISION (gimple_expr_type (def_stmt))
+ == TYPE_PRECISION (TREE_TYPE (gimple_assign_rhs1 (def_stmt)))))
+ name3 = gimple_assign_rhs1 (def_stmt);
}
/* If name3 is used later, create an ASSERT_EXPR for it. */
&& (cst2 == NULL_TREE
|| TREE_CODE (cst2) == INTEGER_CST)
&& INTEGRAL_TYPE_P (TREE_TYPE (name3))
- && TEST_BIT (found_in_subgraph, SSA_NAME_VERSION (name3))
+ && live_on_edge (e, name3)
&& !has_single_use (name3))
{
tree tmp;
&& TREE_CODE (name2) == SSA_NAME
&& TREE_CODE (cst2) == INTEGER_CST
&& INTEGRAL_TYPE_P (TREE_TYPE (name2))
- && TEST_BIT (found_in_subgraph, SSA_NAME_VERSION (name2))
+ && live_on_edge (e, name2)
&& !has_single_use (name2))
{
tree tmp;
/* OP is an operand of a truth value expression which is known to have
a particular value. Register any asserts for OP and for any
- operands in OP's defining statement.
+ operands in OP's defining statement.
If CODE is EQ_EXPR, then we want to register OP is zero (false),
if CODE is NE_EXPR, then we want to register OP is nonzero (true). */
static bool
register_edge_assert_for_1 (tree op, enum tree_code code,
- edge e, block_stmt_iterator bsi)
+ edge e, gimple_stmt_iterator bsi)
{
bool retval = false;
- tree op_def, rhs, val;
+ gimple op_def;
+ tree val;
enum tree_code rhs_code;
/* We only care about SSA_NAMEs. */
return false;
/* We know that OP will have a zero or nonzero value. If OP is used
- more than once go ahead and register an assert for OP.
+ more than once go ahead and register an assert for OP.
The FOUND_IN_SUBGRAPH support is not helpful in this situation as
it will always be set for OP (because OP is used in a COND_EXPR in
a truth operation or some bit operations, then we may be able
to register information about the operands of that assignment. */
op_def = SSA_NAME_DEF_STMT (op);
- if (TREE_CODE (op_def) != GIMPLE_MODIFY_STMT)
+ if (gimple_code (op_def) != GIMPLE_ASSIGN)
return retval;
- rhs = GIMPLE_STMT_OPERAND (op_def, 1);
- rhs_code = TREE_CODE (rhs);
+ rhs_code = gimple_assign_rhs_code (op_def);
- if (COMPARISON_CLASS_P (rhs))
+ if (TREE_CODE_CLASS (rhs_code) == tcc_comparison)
{
bool invert = (code == EQ_EXPR ? true : false);
- tree op0 = TREE_OPERAND (rhs, 0);
- tree op1 = TREE_OPERAND (rhs, 1);
+ tree op0 = gimple_assign_rhs1 (op_def);
+ tree op1 = gimple_assign_rhs2 (op_def);
if (TREE_CODE (op0) == SSA_NAME)
retval |= register_edge_assert_for_2 (op0, e, bsi, rhs_code, op0, op1,
invert);
}
else if ((code == NE_EXPR
- && (TREE_CODE (rhs) == TRUTH_AND_EXPR
- || TREE_CODE (rhs) == BIT_AND_EXPR))
+ && (gimple_assign_rhs_code (op_def) == TRUTH_AND_EXPR
+ || gimple_assign_rhs_code (op_def) == BIT_AND_EXPR))
|| (code == EQ_EXPR
- && (TREE_CODE (rhs) == TRUTH_OR_EXPR
- || TREE_CODE (rhs) == BIT_IOR_EXPR)))
+ && (gimple_assign_rhs_code (op_def) == TRUTH_OR_EXPR
+ || gimple_assign_rhs_code (op_def) == BIT_IOR_EXPR)))
{
/* Recurse on each operand. */
- retval |= register_edge_assert_for_1 (TREE_OPERAND (rhs, 0),
+ retval |= register_edge_assert_for_1 (gimple_assign_rhs1 (op_def),
code, e, bsi);
- retval |= register_edge_assert_for_1 (TREE_OPERAND (rhs, 1),
+ retval |= register_edge_assert_for_1 (gimple_assign_rhs2 (op_def),
code, e, bsi);
}
- else if (TREE_CODE (rhs) == TRUTH_NOT_EXPR)
+ else if (gimple_assign_rhs_code (op_def) == TRUTH_NOT_EXPR)
{
/* Recurse, flipping CODE. */
code = invert_tree_comparison (code, false);
- retval |= register_edge_assert_for_1 (TREE_OPERAND (rhs, 0),
+ retval |= register_edge_assert_for_1 (gimple_assign_rhs1 (op_def),
code, e, bsi);
}
- else if (TREE_CODE (rhs) == SSA_NAME)
+ else if (gimple_assign_rhs_code (op_def) == SSA_NAME)
{
/* Recurse through the copy. */
- retval |= register_edge_assert_for_1 (rhs, code, e, bsi);
+ retval |= register_edge_assert_for_1 (gimple_assign_rhs1 (op_def),
+ code, e, bsi);
}
- else if (TREE_CODE (rhs) == NOP_EXPR
- || TREE_CODE (rhs) == CONVERT_EXPR
- || TREE_CODE (rhs) == NON_LVALUE_EXPR)
- {
+ else if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (op_def)))
+ {
/* Recurse through the type conversion. */
- retval |= register_edge_assert_for_1 (TREE_OPERAND (rhs, 0),
+ retval |= register_edge_assert_for_1 (gimple_assign_rhs1 (op_def),
code, e, bsi);
}
Return true if an assertion for NAME could be registered. */
static bool
-register_edge_assert_for (tree name, edge e, block_stmt_iterator si,
+register_edge_assert_for (tree name, edge e, gimple_stmt_iterator si,
enum tree_code cond_code, tree cond_op0,
tree cond_op1)
{
if (((comp_code == EQ_EXPR && integer_onep (val))
|| (comp_code == NE_EXPR && integer_zerop (val))))
{
- tree def_stmt = SSA_NAME_DEF_STMT (name);
+ gimple def_stmt = SSA_NAME_DEF_STMT (name);
- if (TREE_CODE (def_stmt) == GIMPLE_MODIFY_STMT
- && (TREE_CODE (GIMPLE_STMT_OPERAND (def_stmt, 1)) == TRUTH_AND_EXPR
- || TREE_CODE (GIMPLE_STMT_OPERAND (def_stmt, 1)) == BIT_AND_EXPR))
+ if (is_gimple_assign (def_stmt)
+ && (gimple_assign_rhs_code (def_stmt) == TRUTH_AND_EXPR
+ || gimple_assign_rhs_code (def_stmt) == BIT_AND_EXPR))
{
- tree op0 = TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1), 0);
- tree op1 = TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1), 1);
+ tree op0 = gimple_assign_rhs1 (def_stmt);
+ tree op1 = gimple_assign_rhs2 (def_stmt);
retval |= register_edge_assert_for_1 (op0, NE_EXPR, e, si);
retval |= register_edge_assert_for_1 (op1, NE_EXPR, e, si);
}
if (((comp_code == EQ_EXPR && integer_zerop (val))
|| (comp_code == NE_EXPR && integer_onep (val))))
{
- tree def_stmt = SSA_NAME_DEF_STMT (name);
+ gimple def_stmt = SSA_NAME_DEF_STMT (name);
- if (TREE_CODE (def_stmt) == GIMPLE_MODIFY_STMT
- && (TREE_CODE (GIMPLE_STMT_OPERAND (def_stmt, 1)) == TRUTH_OR_EXPR
+ if (is_gimple_assign (def_stmt)
+ && (gimple_assign_rhs_code (def_stmt) == TRUTH_OR_EXPR
/* For BIT_IOR_EXPR only if NAME == 0 both operands have
necessarily zero value. */
|| (comp_code == EQ_EXPR
- && (TREE_CODE (GIMPLE_STMT_OPERAND (def_stmt, 1))
- == BIT_IOR_EXPR))))
+ && (gimple_assign_rhs_code (def_stmt) == BIT_IOR_EXPR))))
{
- tree op0 = TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1), 0);
- tree op1 = TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1), 1);
+ tree op0 = gimple_assign_rhs1 (def_stmt);
+ tree op1 = gimple_assign_rhs2 (def_stmt);
retval |= register_edge_assert_for_1 (op0, EQ_EXPR, e, si);
retval |= register_edge_assert_for_1 (op1, EQ_EXPR, e, si);
}
}
-static bool find_assert_locations (basic_block bb);
-
/* Determine whether the outgoing edges of BB should receive an
ASSERT_EXPR for each of the operands of BB's LAST statement.
The last statement of BB must be a COND_EXPR.
list of assertions for the corresponding operands. */
static bool
-find_conditional_asserts (basic_block bb, tree last)
+find_conditional_asserts (basic_block bb, gimple last)
{
bool need_assert;
- block_stmt_iterator bsi;
+ gimple_stmt_iterator bsi;
tree op;
edge_iterator ei;
edge e;
ssa_op_iter iter;
need_assert = false;
- bsi = bsi_for_stmt (last);
+ bsi = gsi_for_stmt (last);
/* Look for uses of the operands in each of the sub-graphs
rooted at BB. We need to check each of the outgoing edges
if (e->dest == bb)
continue;
- /* Remove the COND_EXPR operands from the FOUND_IN_SUBGRAPH bitmap.
- Otherwise, when we finish traversing each of the sub-graphs, we
- won't know whether the variables were found in the sub-graphs or
- if they had been found in a block upstream from BB.
-
- This is actually a bad idea is some cases, particularly jump
- threading. Consider a CFG like the following:
-
- 0
- /|
- 1 |
- \|
- 2
- / \
- 3 4
-
- Assume that one or more operands in the conditional at the
- end of block 0 are used in a conditional in block 2, but not
- anywhere in block 1. In this case we will not insert any
- assert statements in block 1, which may cause us to miss
- opportunities to optimize, particularly for jump threading. */
- FOR_EACH_SSA_TREE_OPERAND (op, last, iter, SSA_OP_USE)
- RESET_BIT (found_in_subgraph, SSA_NAME_VERSION (op));
-
- /* Traverse the strictly dominated sub-graph rooted at E->DEST
- to determine if any of the operands in the conditional
- predicate are used. */
- need_assert |= find_assert_locations (e->dest);
-
/* Register the necessary assertions for each operand in the
conditional predicate. */
FOR_EACH_SSA_TREE_OPERAND (op, last, iter, SSA_OP_USE)
{
- tree cond = COND_EXPR_COND (last);
- if (op != cond)
- need_assert |= register_edge_assert_for (op, e, bsi,
- TREE_CODE (cond),
- TREE_OPERAND (cond, 0),
- TREE_OPERAND (cond, 1));
- else
- need_assert |= register_edge_assert_for (op, e, bsi, EQ_EXPR, op,
- boolean_true_node);
+ need_assert |= register_edge_assert_for (op, e, bsi,
+ gimple_cond_code (last),
+ gimple_cond_lhs (last),
+ gimple_cond_rhs (last));
}
}
- /* Finally, indicate that we have found the operands in the
- conditional. */
- FOR_EACH_SSA_TREE_OPERAND (op, last, iter, SSA_OP_USE)
- SET_BIT (found_in_subgraph, SSA_NAME_VERSION (op));
-
return need_assert;
}
list of assertions for the corresponding operands. */
static bool
-find_switch_asserts (basic_block bb, tree last)
+find_switch_asserts (basic_block bb, gimple last)
{
bool need_assert;
- block_stmt_iterator bsi;
+ gimple_stmt_iterator bsi;
tree op;
edge e;
- tree vec = SWITCH_LABELS (last), vec2;
- size_t n = TREE_VEC_LENGTH (vec);
+ 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 = bsi_for_stmt (last);
- op = TREE_OPERAND (last, 0);
+ bsi = gsi_for_stmt (last);
+ op = gimple_switch_index (last);
if (TREE_CODE (op) != SSA_NAME)
return false;
/* Build a vector of case labels sorted by destination label. */
vec2 = make_tree_vec (n);
for (idx = 0; idx < n; ++idx)
- TREE_VEC_ELT (vec2, idx) = TREE_VEC_ELT (vec, idx);
+ TREE_VEC_ELT (vec2, idx) = gimple_switch_label (last, idx);
qsort (&TREE_VEC_ELT (vec2, 0), n, sizeof (tree), compare_case_labels);
for (idx = 0; idx < n; ++idx)
/* Find the edge to register the assert expr on. */
e = find_edge (bb, label_to_block (CASE_LABEL (cl)));
- /* Remove the SWITCH_EXPR operand from the FOUND_IN_SUBGRAPH bitmap.
- Otherwise, when we finish traversing each of the sub-graphs, we
- won't know whether the variables were found in the sub-graphs or
- if they had been found in a block upstream from BB. */
- RESET_BIT (found_in_subgraph, SSA_NAME_VERSION (op));
-
- /* Traverse the strictly dominated sub-graph rooted at E->DEST
- to determine if any of the operands in the conditional
- predicate are used. */
- if (e->dest != bb)
- need_assert |= find_assert_locations (e->dest);
-
/* Register the necessary assertions for the operand in the
SWITCH_EXPR. */
need_assert |= register_edge_assert_for (op, e, bsi,
}
}
- /* Finally, indicate that we have found the operand in the
- SWITCH_EXPR. */
- SET_BIT (found_in_subgraph, SSA_NAME_VERSION (op));
-
return need_assert;
}
If a statement produces a useful assertion A for name N_i, then the
list of assertions already generated for N_i is scanned to
determine if A is actually needed.
-
+
If N_i already had the assertion A at a location dominating the
current location, then nothing needs to be done. Otherwise, the
new location for A is recorded instead.
4- If BB does not end in a conditional expression, then we recurse
into BB's dominator children.
-
+
At the end of the recursive traversal, every SSA name will have a
list of locations where ASSERT_EXPRs should be added. When a new
location for name N is found, it is registered by calling
inserted by process_assert_insertions. */
static bool
-find_assert_locations (basic_block bb)
+find_assert_locations_1 (basic_block bb, sbitmap live)
{
- block_stmt_iterator si;
- tree last, phi;
+ gimple_stmt_iterator si;
+ gimple last;
+ gimple phi;
bool need_assert;
- basic_block son;
-
- if (TEST_BIT (blocks_visited, bb->index))
- return false;
-
- SET_BIT (blocks_visited, bb->index);
need_assert = false;
+ last = last_stmt (bb);
- /* Traverse all PHI nodes in BB marking used operands. */
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- {
- use_operand_p arg_p;
- ssa_op_iter i;
+ /* If BB's last statement is a conditional statement involving integer
+ operands, determine if we need to add ASSERT_EXPRs. */
+ if (last
+ && gimple_code (last) == GIMPLE_COND
+ && !fp_predicate (last)
+ && !ZERO_SSA_OPERANDS (last, SSA_OP_USE))
+ need_assert |= find_conditional_asserts (bb, last);
- FOR_EACH_PHI_ARG (arg_p, phi, i, SSA_OP_USE)
- {
- tree arg = USE_FROM_PTR (arg_p);
- if (TREE_CODE (arg) == SSA_NAME)
- {
- gcc_assert (is_gimple_reg (PHI_RESULT (phi)));
- SET_BIT (found_in_subgraph, SSA_NAME_VERSION (arg));
- }
- }
- }
+ /* If BB's last statement is a switch statement involving integer
+ operands, determine if we need to add ASSERT_EXPRs. */
+ if (last
+ && gimple_code (last) == GIMPLE_SWITCH
+ && !ZERO_SSA_OPERANDS (last, SSA_OP_USE))
+ need_assert |= find_switch_asserts (bb, last);
/* Traverse all the statements in BB marking used names and looking
for statements that may infer assertions for their used operands. */
- last = NULL_TREE;
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
+ for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
{
- tree stmt, op;
+ gimple stmt;
+ tree op;
ssa_op_iter i;
- stmt = bsi_stmt (si);
+ stmt = gsi_stmt (si);
+
+ if (is_gimple_debug (stmt))
+ continue;
/* See if we can derive an assertion for any of STMT's operands. */
FOR_EACH_SSA_TREE_OPERAND (op, stmt, i, SSA_OP_USE)
tree value;
enum tree_code comp_code;
- /* Mark OP in bitmap FOUND_IN_SUBGRAPH. If STMT is inside
- the sub-graph of a conditional block, when we return from
- this recursive walk, our parent will use the
- FOUND_IN_SUBGRAPH bitset to determine if one of the
- operands it was looking for was present in the sub-graph. */
- SET_BIT (found_in_subgraph, SSA_NAME_VERSION (op));
+ /* Mark OP in our live bitmap. */
+ SET_BIT (live, SSA_NAME_VERSION (op));
/* If OP is used in such a way that we can infer a value
range for it, and we don't find a previous assertion for
if (comp_code == NE_EXPR && integer_zerop (value))
{
tree t = op;
- tree def_stmt = SSA_NAME_DEF_STMT (t);
-
- while (TREE_CODE (def_stmt) == GIMPLE_MODIFY_STMT
- && TREE_CODE
- (GIMPLE_STMT_OPERAND (def_stmt, 1)) == NOP_EXPR
+ gimple def_stmt = SSA_NAME_DEF_STMT (t);
+
+ while (is_gimple_assign (def_stmt)
+ && gimple_assign_rhs_code (def_stmt) == NOP_EXPR
&& TREE_CODE
- (TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1),
- 0)) == SSA_NAME
+ (gimple_assign_rhs1 (def_stmt)) == SSA_NAME
&& POINTER_TYPE_P
- (TREE_TYPE (TREE_OPERAND
- (GIMPLE_STMT_OPERAND (def_stmt,
- 1), 0))))
+ (TREE_TYPE (gimple_assign_rhs1 (def_stmt))))
{
- t = TREE_OPERAND (GIMPLE_STMT_OPERAND (def_stmt, 1), 0);
+ t = gimple_assign_rhs1 (def_stmt);
def_stmt = SSA_NAME_DEF_STMT (t);
/* Note we want to register the assert for the
}
}
}
-
- /* Remember the last statement of the block. */
- last = stmt;
}
- /* If BB's last statement is a conditional expression
- involving integer operands, recurse into each of the sub-graphs
- rooted at BB to determine if we need to add ASSERT_EXPRs. */
- if (last
- && TREE_CODE (last) == COND_EXPR
- && !fp_predicate (COND_EXPR_COND (last))
- && !ZERO_SSA_OPERANDS (last, SSA_OP_USE))
- need_assert |= find_conditional_asserts (bb, last);
-
- if (last
- && TREE_CODE (last) == SWITCH_EXPR
- && !ZERO_SSA_OPERANDS (last, SSA_OP_USE))
- need_assert |= find_switch_asserts (bb, last);
+ /* Traverse all PHI nodes in BB marking used operands. */
+ for (si = gsi_start_phis (bb); !gsi_end_p(si); gsi_next (&si))
+ {
+ use_operand_p arg_p;
+ ssa_op_iter i;
+ phi = gsi_stmt (si);
- /* Recurse into the dominator children of BB. */
- for (son = first_dom_son (CDI_DOMINATORS, bb);
- son;
- son = next_dom_son (CDI_DOMINATORS, son))
- need_assert |= find_assert_locations (son);
+ FOR_EACH_PHI_ARG (arg_p, phi, i, SSA_OP_USE)
+ {
+ tree arg = USE_FROM_PTR (arg_p);
+ if (TREE_CODE (arg) == SSA_NAME)
+ SET_BIT (live, SSA_NAME_VERSION (arg));
+ }
+ }
return need_assert;
}
+/* Do an RPO walk over the function computing SSA name liveness
+ on-the-fly and deciding on assert expressions to insert.
+ Returns true if there are assert expressions to be inserted. */
+
+static bool
+find_assert_locations (void)
+{
+ int *rpo = XCNEWVEC (int, last_basic_block + NUM_FIXED_BLOCKS);
+ int *bb_rpo = XCNEWVEC (int, last_basic_block + NUM_FIXED_BLOCKS);
+ int *last_rpo = XCNEWVEC (int, last_basic_block + NUM_FIXED_BLOCKS);
+ int rpo_cnt, i;
+ bool need_asserts;
+
+ live = XCNEWVEC (sbitmap, last_basic_block + NUM_FIXED_BLOCKS);
+ rpo_cnt = pre_and_rev_post_order_compute (NULL, rpo, false);
+ for (i = 0; i < rpo_cnt; ++i)
+ bb_rpo[rpo[i]] = i;
+
+ need_asserts = false;
+ for (i = rpo_cnt-1; i >= 0; --i)
+ {
+ basic_block bb = BASIC_BLOCK (rpo[i]);
+ edge e;
+ edge_iterator ei;
+
+ if (!live[rpo[i]])
+ {
+ live[rpo[i]] = sbitmap_alloc (num_ssa_names);
+ sbitmap_zero (live[rpo[i]]);
+ }
+
+ /* Process BB and update the live information with uses in
+ this block. */
+ need_asserts |= find_assert_locations_1 (bb, live[rpo[i]]);
+
+ /* Merge liveness into the predecessor blocks and free it. */
+ if (!sbitmap_empty_p (live[rpo[i]]))
+ {
+ int pred_rpo = i;
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ {
+ int pred = e->src->index;
+ if (e->flags & EDGE_DFS_BACK)
+ continue;
+
+ if (!live[pred])
+ {
+ live[pred] = sbitmap_alloc (num_ssa_names);
+ sbitmap_zero (live[pred]);
+ }
+ sbitmap_a_or_b (live[pred], live[pred], live[rpo[i]]);
+
+ if (bb_rpo[pred] < pred_rpo)
+ pred_rpo = bb_rpo[pred];
+ }
+
+ /* Record the RPO number of the last visited block that needs
+ live information from this block. */
+ last_rpo[rpo[i]] = pred_rpo;
+ }
+ else
+ {
+ sbitmap_free (live[rpo[i]]);
+ live[rpo[i]] = NULL;
+ }
+
+ /* We can free all successors live bitmaps if all their
+ predecessors have been visited already. */
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (last_rpo[e->dest->index] == i
+ && live[e->dest->index])
+ {
+ sbitmap_free (live[e->dest->index]);
+ live[e->dest->index] = NULL;
+ }
+ }
+
+ XDELETEVEC (rpo);
+ XDELETEVEC (bb_rpo);
+ XDELETEVEC (last_rpo);
+ for (i = 0; i < last_basic_block + NUM_FIXED_BLOCKS; ++i)
+ if (live[i])
+ sbitmap_free (live[i]);
+ XDELETEVEC (live);
+
+ return need_asserts;
+}
/* Create an ASSERT_EXPR for NAME and insert it in the location
indicated by LOC. Return true if we made any edge insertions. */
process_assert_insertions_for (tree name, assert_locus_t loc)
{
/* Build the comparison expression NAME_i COMP_CODE VAL. */
- tree stmt, cond, assert_expr;
+ gimple stmt;
+ tree cond;
+ gimple assert_stmt;
edge_iterator ei;
edge e;
- cond = build2 (loc->comp_code, boolean_type_node, loc->expr, loc->val);
- assert_expr = build_assert_expr_for (cond, name);
+ /* If we have X <=> X do not insert an assert expr for that. */
+ if (loc->expr == loc->val)
+ return false;
+ cond = build2 (loc->comp_code, boolean_type_node, loc->expr, loc->val);
+ assert_stmt = build_assert_expr_for (cond, name);
if (loc->e)
{
/* We have been asked to insert the assertion on an edge. This
is used only by COND_EXPR and SWITCH_EXPR assertions. */
#if defined ENABLE_CHECKING
- gcc_assert (TREE_CODE (bsi_stmt (loc->si)) == COND_EXPR
- || TREE_CODE (bsi_stmt (loc->si)) == SWITCH_EXPR);
+ gcc_assert (gimple_code (gsi_stmt (loc->si)) == GIMPLE_COND
+ || gimple_code (gsi_stmt (loc->si)) == GIMPLE_SWITCH);
#endif
- bsi_insert_on_edge (loc->e, assert_expr);
+ gsi_insert_on_edge (loc->e, assert_stmt);
return true;
}
/* Otherwise, we can insert right after LOC->SI iff the
statement must not be the last statement in the block. */
- stmt = bsi_stmt (loc->si);
+ stmt = gsi_stmt (loc->si);
if (!stmt_ends_bb_p (stmt))
{
- bsi_insert_after (&loc->si, assert_expr, BSI_SAME_STMT);
+ gsi_insert_after (&loc->si, assert_stmt, GSI_SAME_STMT);
return false;
}
FOR_EACH_EDGE (e, ei, loc->bb->succs)
if (!(e->flags & EDGE_ABNORMAL))
{
- bsi_insert_on_edge (e, assert_expr);
+ gsi_insert_on_edge (e, assert_stmt);
return true;
}
}
if (update_edges_p)
- bsi_commit_edge_inserts ();
+ gsi_commit_edge_inserts ();
- if (dump_file && (dump_flags & TDF_STATS))
- fprintf (dump_file, "\nNumber of ASSERT_EXPR expressions inserted: %d\n\n",
- num_asserts);
+ statistics_counter_event (cfun, "Number of ASSERT_EXPR expressions inserted",
+ num_asserts);
}
static void
insert_range_assertions (void)
{
- edge e;
- edge_iterator ei;
- bool update_ssa_p;
-
- found_in_subgraph = sbitmap_alloc (num_ssa_names);
- sbitmap_zero (found_in_subgraph);
-
- blocks_visited = sbitmap_alloc (last_basic_block);
- sbitmap_zero (blocks_visited);
-
need_assert_for = BITMAP_ALLOC (NULL);
asserts_for = XCNEWVEC (assert_locus_t, num_ssa_names);
calculate_dominance_info (CDI_DOMINATORS);
- update_ssa_p = false;
- FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
- if (find_assert_locations (e->dest))
- update_ssa_p = true;
-
- if (update_ssa_p)
+ if (find_assert_locations ())
{
process_assert_insertions ();
update_ssa (TODO_update_ssa_no_phi);
dump_function_to_file (current_function_decl, dump_file, dump_flags);
}
- sbitmap_free (found_in_subgraph);
free (asserts_for);
BITMAP_FREE (need_assert_for);
}
IGNORE_OFF_BY_ONE is true if the ARRAY_REF is inside a ADDR_EXPR. */
static void
-check_array_ref (tree ref, location_t* locus, bool ignore_off_by_one)
+check_array_ref (location_t location, tree ref, bool ignore_off_by_one)
{
value_range_t* vr = NULL;
tree low_sub, up_sub;
- tree low_bound, up_bound = array_ref_up_bound (ref);
+ tree low_bound, up_bound, up_bound_p1;
+ tree base;
+
+ if (TREE_NO_WARNING (ref))
+ return;
low_sub = up_sub = TREE_OPERAND (ref, 1);
+ up_bound = array_ref_up_bound (ref);
- if (!up_bound || TREE_NO_WARNING (ref)
- || TREE_CODE (up_bound) != INTEGER_CST
- /* Can not check flexible arrays. */
- || (TYPE_SIZE (TREE_TYPE (ref)) == NULL_TREE
- && TYPE_DOMAIN (TREE_TYPE (ref)) != NULL_TREE
- && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (ref))) == NULL_TREE)
- /* Accesses after the end of arrays of size 0 (gcc
- extension) and 1 are likely intentional ("struct
- hack"). */
- || compare_tree_int (up_bound, 1) <= 0)
+ /* Can not check flexible arrays. */
+ if (!up_bound
+ || TREE_CODE (up_bound) != INTEGER_CST)
return;
+ /* Accesses to trailing arrays via pointers may access storage
+ beyond the types array bounds. */
+ base = get_base_address (ref);
+ if (base
+ && INDIRECT_REF_P (base))
+ {
+ tree cref, next = NULL_TREE;
+
+ if (TREE_CODE (TREE_OPERAND (ref, 0)) != COMPONENT_REF)
+ return;
+
+ cref = TREE_OPERAND (ref, 0);
+ if (TREE_CODE (TREE_TYPE (TREE_OPERAND (cref, 0))) == RECORD_TYPE)
+ for (next = TREE_CHAIN (TREE_OPERAND (cref, 1));
+ next && TREE_CODE (next) != FIELD_DECL;
+ next = TREE_CHAIN (next))
+ ;
+
+ /* If this is the last field in a struct type or a field in a
+ union type do not warn. */
+ if (!next)
+ return;
+ }
+
low_bound = array_ref_low_bound (ref);
+ up_bound_p1 = int_const_binop (PLUS_EXPR, up_bound, integer_one_node, 0);
if (TREE_CODE (low_sub) == SSA_NAME)
{
&& TREE_CODE (low_sub) == INTEGER_CST
&& tree_int_cst_lt (low_sub, low_bound))
{
- warning (OPT_Warray_bounds,
- "%Harray subscript is outside array bounds", locus);
+ warning_at (location, OPT_Warray_bounds,
+ "array subscript is outside array bounds");
TREE_NO_WARNING (ref) = 1;
}
}
else if (TREE_CODE (up_sub) == INTEGER_CST
- && tree_int_cst_lt (up_bound, up_sub)
- && !tree_int_cst_equal (up_bound, up_sub)
- && (!ignore_off_by_one
- || !tree_int_cst_equal (int_const_binop (PLUS_EXPR,
- up_bound,
- integer_one_node,
- 0),
- up_sub)))
- {
- warning (OPT_Warray_bounds, "%Harray subscript is above array bounds",
- locus);
+ && (ignore_off_by_one
+ ? (tree_int_cst_lt (up_bound, up_sub)
+ && !tree_int_cst_equal (up_bound_p1, up_sub))
+ : (tree_int_cst_lt (up_bound, up_sub)
+ || tree_int_cst_equal (up_bound_p1, up_sub))))
+ {
+ warning_at (location, OPT_Warray_bounds,
+ "array subscript is above array bounds");
TREE_NO_WARNING (ref) = 1;
}
else if (TREE_CODE (low_sub) == INTEGER_CST
&& tree_int_cst_lt (low_sub, low_bound))
{
- warning (OPT_Warray_bounds, "%Harray subscript is below array bounds",
- locus);
+ warning_at (location, OPT_Warray_bounds,
+ "array subscript is below array bounds");
TREE_NO_WARNING (ref) = 1;
}
}
address of an ARRAY_REF, and call check_array_ref on it. */
static void
-search_for_addr_array(tree t, location_t* location)
+search_for_addr_array (tree t, location_t location)
{
while (TREE_CODE (t) == SSA_NAME)
{
- t = SSA_NAME_DEF_STMT (t);
- if (TREE_CODE (t) != GIMPLE_MODIFY_STMT)
+ gimple g = SSA_NAME_DEF_STMT (t);
+
+ if (gimple_code (g) != GIMPLE_ASSIGN)
+ return;
+
+ if (get_gimple_rhs_class (gimple_assign_rhs_code (g))
+ != GIMPLE_SINGLE_RHS)
return;
- t = GIMPLE_STMT_OPERAND (t, 1);
+
+ t = gimple_assign_rhs1 (g);
}
/* We are only interested in addresses of ARRAY_REF's. */
- if (TREE_CODE (t) != ADDR_EXPR)
+ if (TREE_CODE (t) != ADDR_EXPR)
return;
/* Check each ARRAY_REFs in the reference chain. */
- do
+ do
{
if (TREE_CODE (t) == ARRAY_REF)
- check_array_ref (t, location, true /*ignore_off_by_one*/);
+ check_array_ref (location, t, true /*ignore_off_by_one*/);
- t = TREE_OPERAND(t,0);
+ t = TREE_OPERAND (t, 0);
}
while (handled_component_p (t));
}
/* walk_tree() callback that checks if *TP is
an ARRAY_REF inside an ADDR_EXPR (in which an array
subscript one outside the valid range is allowed). Call
- check_array_ref for each ARRAY_REF found. The location is
+ check_array_ref for each ARRAY_REF found. The location is
passed in DATA. */
static tree
check_array_bounds (tree *tp, int *walk_subtree, void *data)
{
tree t = *tp;
- tree stmt = (tree)data;
- location_t *location = EXPR_LOCUS (stmt);
+ struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
+ location_t location;
- if (!EXPR_HAS_LOCATION (stmt))
+ if (EXPR_HAS_LOCATION (t))
+ location = EXPR_LOCATION (t);
+ else
{
- *walk_subtree = FALSE;
- return NULL_TREE;
+ location_t *locp = (location_t *) wi->info;
+ location = *locp;
}
*walk_subtree = TRUE;
if (TREE_CODE (t) == ARRAY_REF)
- check_array_ref (t, location, false /*ignore_off_by_one*/);
+ check_array_ref (location, t, false /*ignore_off_by_one*/);
if (TREE_CODE (t) == INDIRECT_REF
|| (TREE_CODE (t) == RETURN_EXPR && TREE_OPERAND (t, 0)))
search_for_addr_array (TREE_OPERAND (t, 0), location);
- else if (TREE_CODE (t) == CALL_EXPR)
- {
- tree arg;
- call_expr_arg_iterator iter;
-
- FOR_EACH_CALL_EXPR_ARG (arg, iter, t)
- search_for_addr_array (arg, location);
- }
if (TREE_CODE (t) == ADDR_EXPR)
*walk_subtree = FALSE;
check_all_array_refs (void)
{
basic_block bb;
- block_stmt_iterator si;
+ gimple_stmt_iterator si;
FOR_EACH_BB (bb)
{
- /* Skip bb's that are clearly unreachable. */
- if (single_pred_p (bb))
- {
- basic_block pred_bb = EDGE_PRED (bb, 0)->src;
- tree ls = NULL_TREE;
+ edge_iterator ei;
+ edge e;
+ bool executable = false;
- if (!bsi_end_p (bsi_last (pred_bb)))
- ls = bsi_stmt (bsi_last (pred_bb));
+ /* Skip blocks that were found to be unreachable. */
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ executable |= !!(e->flags & EDGE_EXECUTABLE);
+ if (!executable)
+ continue;
- if (ls && TREE_CODE (ls) == COND_EXPR
- && ((COND_EXPR_COND (ls) == boolean_false_node
- && (EDGE_PRED (bb, 0)->flags & EDGE_TRUE_VALUE))
- || (COND_EXPR_COND (ls) == boolean_true_node
- && (EDGE_PRED (bb, 0)->flags & EDGE_FALSE_VALUE))))
- continue;
- }
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- walk_tree (bsi_stmt_ptr (si), check_array_bounds,
- bsi_stmt (si), NULL);
+ for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
+ {
+ gimple stmt = gsi_stmt (si);
+ struct walk_stmt_info wi;
+ if (!gimple_has_location (stmt))
+ continue;
+
+ if (is_gimple_call (stmt))
+ {
+ size_t i;
+ size_t n = gimple_call_num_args (stmt);
+ for (i = 0; i < n; i++)
+ {
+ tree arg = gimple_call_arg (stmt, i);
+ search_for_addr_array (arg, gimple_location (stmt));
+ }
+ }
+ else
+ {
+ memset (&wi, 0, sizeof (wi));
+ wi.info = CONST_CAST (void *, (const void *)
+ gimple_location_ptr (stmt));
+
+ walk_gimple_op (gsi_stmt (si),
+ check_array_bounds,
+ &wi);
+ }
+ }
}
}
/* Convert range assertion expressions into the implied copies and
copy propagate away the copies. Doing the trivial copy propagation
here avoids the need to run the full copy propagation pass after
- VRP.
-
+ VRP.
+
FIXME, this will eventually lead to copy propagation removing the
names that had useful range information attached to them. For
instance, if we had the assertion N_i = ASSERT_EXPR <N_j, N_j > 3>,
then N_i will have the range [3, +INF].
-
+
However, by converting the assertion into the implied copy
operation N_i = N_j, we will then copy-propagate N_j into the uses
of N_i and lose the range information. We may want to hold on to
ASSERT_EXPRs a little while longer as the ranges could be used in
things like jump threading.
-
+
The problem with keeping ASSERT_EXPRs around is that passes after
- VRP need to handle them appropriately.
+ VRP need to handle them appropriately.
Another approach would be to make the range information a first
class property of the SSA_NAME so that it can be queried from
remove_range_assertions (void)
{
basic_block bb;
- block_stmt_iterator si;
+ gimple_stmt_iterator si;
/* Note that the BSI iterator bump happens at the bottom of the
loop and no bump is necessary if we're removing the statement
referenced by the current BSI. */
FOR_EACH_BB (bb)
- for (si = bsi_start (bb); !bsi_end_p (si);)
+ for (si = gsi_start_bb (bb); !gsi_end_p (si);)
{
- tree stmt = bsi_stmt (si);
- tree use_stmt;
+ gimple stmt = gsi_stmt (si);
+ gimple use_stmt;
- if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT
- && TREE_CODE (GIMPLE_STMT_OPERAND (stmt, 1)) == ASSERT_EXPR)
+ if (is_gimple_assign (stmt)
+ && gimple_assign_rhs_code (stmt) == ASSERT_EXPR)
{
- tree rhs = GIMPLE_STMT_OPERAND (stmt, 1), var;
+ tree rhs = gimple_assign_rhs1 (stmt);
+ tree var;
tree cond = fold (ASSERT_EXPR_COND (rhs));
use_operand_p use_p;
imm_use_iterator iter;
/* Propagate the RHS into every use of the LHS. */
var = ASSERT_EXPR_VAR (rhs);
FOR_EACH_IMM_USE_STMT (use_stmt, iter,
- GIMPLE_STMT_OPERAND (stmt, 0))
+ gimple_assign_lhs (stmt))
FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
{
SET_USE (use_p, var);
}
/* And finally, remove the copy, it is not needed. */
- bsi_remove (&si, true);
- release_defs (stmt);
+ gsi_remove (&si, true);
+ release_defs (stmt);
}
else
- bsi_next (&si);
+ gsi_next (&si);
}
-
- sbitmap_free (blocks_visited);
}
/* Return true if STMT is interesting for VRP. */
static bool
-stmt_interesting_for_vrp (tree stmt)
+stmt_interesting_for_vrp (gimple stmt)
{
- if (TREE_CODE (stmt) == PHI_NODE
- && is_gimple_reg (PHI_RESULT (stmt))
- && (INTEGRAL_TYPE_P (TREE_TYPE (PHI_RESULT (stmt)))
- || POINTER_TYPE_P (TREE_TYPE (PHI_RESULT (stmt)))))
+ if (gimple_code (stmt) == GIMPLE_PHI
+ && is_gimple_reg (gimple_phi_result (stmt))
+ && (INTEGRAL_TYPE_P (TREE_TYPE (gimple_phi_result (stmt)))
+ || POINTER_TYPE_P (TREE_TYPE (gimple_phi_result (stmt)))))
return true;
- else if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT)
+ else if (is_gimple_assign (stmt) || is_gimple_call (stmt))
{
- tree lhs = GIMPLE_STMT_OPERAND (stmt, 0);
- tree rhs = GIMPLE_STMT_OPERAND (stmt, 1);
+ tree lhs = gimple_get_lhs (stmt);
/* In general, assignments with virtual operands are not useful
for deriving ranges, with the obvious exception of calls to
builtin functions. */
- if (TREE_CODE (lhs) == SSA_NAME
+ if (lhs && TREE_CODE (lhs) == SSA_NAME
&& (INTEGRAL_TYPE_P (TREE_TYPE (lhs))
|| POINTER_TYPE_P (TREE_TYPE (lhs)))
- && ((TREE_CODE (rhs) == CALL_EXPR
- && TREE_CODE (CALL_EXPR_FN (rhs)) == ADDR_EXPR
- && DECL_P (TREE_OPERAND (CALL_EXPR_FN (rhs), 0))
- && DECL_IS_BUILTIN (TREE_OPERAND (CALL_EXPR_FN (rhs), 0)))
- || ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS)))
+ && ((is_gimple_call (stmt)
+ && gimple_call_fndecl (stmt) != NULL_TREE
+ && DECL_IS_BUILTIN (gimple_call_fndecl (stmt)))
+ || !gimple_vuse (stmt)))
return true;
}
- else if (TREE_CODE (stmt) == COND_EXPR || TREE_CODE (stmt) == SWITCH_EXPR)
+ else if (gimple_code (stmt) == GIMPLE_COND
+ || gimple_code (stmt) == GIMPLE_SWITCH)
return true;
return false;
FOR_EACH_BB (bb)
{
- block_stmt_iterator si;
- tree phi;
+ gimple_stmt_iterator si;
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+ for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si))
{
+ gimple phi = gsi_stmt (si);
if (!stmt_interesting_for_vrp (phi))
{
tree lhs = PHI_RESULT (phi);
set_value_range_to_varying (get_value_range (lhs));
- DONT_SIMULATE_AGAIN (phi) = true;
+ prop_set_simulate_again (phi, false);
}
else
- DONT_SIMULATE_AGAIN (phi) = false;
+ prop_set_simulate_again (phi, true);
}
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
+ for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
{
- tree stmt = bsi_stmt (si);
-
- if (!stmt_interesting_for_vrp (stmt))
+ gimple stmt = gsi_stmt (si);
+
+ /* If the statement is a control insn, then we do not
+ want to avoid simulating the statement once. Failure
+ to do so means that those edges will never get added. */
+ if (stmt_ends_bb_p (stmt))
+ prop_set_simulate_again (stmt, true);
+ else if (!stmt_interesting_for_vrp (stmt))
{
ssa_op_iter i;
tree def;
FOR_EACH_SSA_TREE_OPERAND (def, stmt, i, SSA_OP_DEF)
set_value_range_to_varying (get_value_range (def));
- DONT_SIMULATE_AGAIN (stmt) = true;
+ prop_set_simulate_again (stmt, false);
}
else
- {
- DONT_SIMULATE_AGAIN (stmt) = false;
- }
+ prop_set_simulate_again (stmt, true);
}
}
}
the SSA name in *OUTPUT_P. */
static enum ssa_prop_result
-vrp_visit_assignment (tree stmt, tree *output_p)
+vrp_visit_assignment_or_call (gimple stmt, tree *output_p)
{
- tree lhs, rhs, def;
+ tree def, lhs;
ssa_op_iter iter;
-
- lhs = GIMPLE_STMT_OPERAND (stmt, 0);
- rhs = GIMPLE_STMT_OPERAND (stmt, 1);
+ enum gimple_code code = gimple_code (stmt);
+ lhs = gimple_get_lhs (stmt);
/* We only keep track of ranges in integral and pointer types. */
if (TREE_CODE (lhs) == SSA_NAME
&& TYPE_MAX_VALUE (TREE_TYPE (lhs)))
|| POINTER_TYPE_P (TREE_TYPE (lhs))))
{
- struct loop *l;
value_range_t new_vr = { VR_UNDEFINED, NULL_TREE, NULL_TREE, NULL };
- extract_range_from_expr (&new_vr, rhs);
-
- /* If STMT is inside a loop, we may be able to know something
- else about the range of LHS by examining scalar evolution
- information. */
- if (current_loops && (l = loop_containing_stmt (stmt)))
- adjust_range_with_scev (&new_vr, l, stmt, lhs);
+ if (code == GIMPLE_CALL)
+ extract_range_basic (&new_vr, stmt);
+ else
+ extract_range_from_assignment (&new_vr, stmt);
if (update_value_range (lhs, &new_vr))
{
return SSA_PROP_NOT_INTERESTING;
}
-
+
/* Every other statement produces no useful ranges. */
FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_DEF)
set_value_range_to_varying (get_value_range (def));
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);
+ return compare_names (code, op0, op1, strict_overflow_p);
else if (TREE_CODE (op0) == SSA_NAME)
- return compare_name_with_value (code, op0, op1,
- strict_overflow_p);
+ return compare_name_with_value (code, op0, op1, strict_overflow_p);
else if (TREE_CODE (op1) == SSA_NAME)
return (compare_name_with_value
- (swap_tree_comparison (code), op1, op0,
- strict_overflow_p));
+ (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;
}
-/* Given a conditional predicate COND, try to determine if COND yields
- true or false based on the value ranges of its operands. Return
- BOOLEAN_TRUE_NODE if the conditional always evaluates to true,
- BOOLEAN_FALSE_NODE if the conditional always evaluates to false, and,
- NULL if the conditional cannot be evaluated at compile time.
-
- If USE_EQUIV_P is true, the ranges of all the names equivalent with
- the operands in COND are used when trying to compute its value.
- This is only used during final substitution. During propagation,
- we only check the range of each variable and not its equivalents.
-
- Set *STRICT_OVERFLOW_P to indicate whether we relied on an overflow
- infinity to produce the result. */
-
-static tree
-vrp_evaluate_conditional_warnv (tree cond, bool use_equiv_p,
- bool *strict_overflow_p)
-{
- gcc_assert (TREE_CODE (cond) == SSA_NAME
- || TREE_CODE_CLASS (TREE_CODE (cond)) == tcc_comparison);
-
- if (TREE_CODE (cond) == SSA_NAME)
- {
- value_range_t *vr;
- tree retval;
-
- if (use_equiv_p)
- retval = compare_name_with_value (NE_EXPR, cond, boolean_false_node,
- strict_overflow_p);
- else
- {
- value_range_t *vr = get_value_range (cond);
- retval = compare_range_with_value (NE_EXPR, vr, boolean_false_node,
- strict_overflow_p);
- }
-
- /* If COND has a known boolean range, return it. */
- if (retval)
- return retval;
-
- /* Otherwise, if COND has a symbolic range of exactly one value,
- return it. */
- vr = get_value_range (cond);
- if (vr->type == VR_RANGE && vr->min == vr->max)
- return vr->min;
- }
- else
- return vrp_evaluate_conditional_warnv_with_ops (TREE_CODE (cond),
- TREE_OPERAND (cond, 0),
- TREE_OPERAND (cond, 1),
- use_equiv_p,
- strict_overflow_p);
-
- /* Anything else cannot be computed statically. */
- return NULL_TREE;
-}
-
-/* Given COND within STMT, try to simplify it based on value range
+/* Given (CODE OP0 OP1) within STMT, try to simplify it based on value range
information. Return NULL if the conditional can not be evaluated.
The ranges of all the names equivalent with the operands in COND
will be used when trying to compute the value. If the result is
based on undefined signed overflow, issue a warning if
appropriate. */
-tree
-vrp_evaluate_conditional (tree cond, tree stmt)
+static tree
+vrp_evaluate_conditional (enum tree_code code, tree op0, tree op1, gimple stmt)
{
bool sop;
tree ret;
+ bool only_ranges;
+
+ /* Some passes and foldings leak constants with overflow flag set
+ into the IL. Avoid doing wrong things with these and bail out. */
+ if ((TREE_CODE (op0) == INTEGER_CST
+ && TREE_OVERFLOW (op0))
+ || (TREE_CODE (op1) == INTEGER_CST
+ && TREE_OVERFLOW (op1)))
+ return NULL_TREE;
sop = false;
- ret = vrp_evaluate_conditional_warnv (cond, true, &sop);
+ ret = vrp_evaluate_conditional_warnv_with_ops (code, op0, op1, true, &sop,
+ &only_ranges);
if (ret && sop)
{
if (issue_strict_overflow_warning (wc))
{
- location_t locus;
+ location_t location;
- if (!EXPR_HAS_LOCATION (stmt))
- locus = input_location;
+ if (!gimple_has_location (stmt))
+ location = input_location;
else
- locus = EXPR_LOCATION (stmt);
- warning (OPT_Wstrict_overflow, "%H%s", &locus, warnmsg);
+ location = gimple_location (stmt);
+ warning_at (location, OPT_Wstrict_overflow, "%s", warnmsg);
}
}
if (warn_type_limits
- && ret
- && TREE_CODE_CLASS (TREE_CODE (cond)) == tcc_comparison)
+ && ret && only_ranges
+ && TREE_CODE_CLASS (code) == tcc_comparison
+ && TREE_CODE (op0) == SSA_NAME)
{
/* If the comparison is being folded and the operand on the LHS
is being compared against a constant value that is outside of
the natural range of OP0's type, then the predicate will
always fold regardless of the value of OP0. If -Wtype-limits
was specified, emit a warning. */
- const char *warnmsg = NULL;
- tree op0 = TREE_OPERAND (cond, 0);
- tree op1 = TREE_OPERAND (cond, 1);
tree type = TREE_TYPE (op0);
value_range_t *vr0 = get_value_range (op0);
&& vrp_val_is_max (vr0->max)
&& is_gimple_min_invariant (op1))
{
- if (integer_zerop (ret))
- warnmsg = G_("comparison always false due to limited range of "
- "data type");
- else
- warnmsg = G_("comparison always true due to limited range of "
- "data type");
- }
+ location_t location;
- if (warnmsg)
- {
- location_t locus;
-
- if (!EXPR_HAS_LOCATION (stmt))
- locus = input_location;
+ if (!gimple_has_location (stmt))
+ location = input_location;
else
- locus = EXPR_LOCATION (stmt);
-
- warning (OPT_Wtype_limits, "%H%s", &locus, warnmsg);
+ location = gimple_location (stmt);
+
+ warning_at (location, OPT_Wtype_limits,
+ integer_zerop (ret)
+ ? G_("comparison always false "
+ "due to limited range of data type")
+ : G_("comparison always true "
+ "due to limited range of data type"));
}
}
SSA_PROP_VARYING. */
static enum ssa_prop_result
-vrp_visit_cond_stmt (tree stmt, edge *taken_edge_p)
+vrp_visit_cond_stmt (gimple stmt, edge *taken_edge_p)
{
- tree cond, val;
+ tree val;
bool sop;
*taken_edge_p = NULL;
- cond = COND_EXPR_COND (stmt);
if (dump_file && (dump_flags & TDF_DETAILS))
{
ssa_op_iter i;
fprintf (dump_file, "\nVisiting conditional with predicate: ");
- print_generic_expr (dump_file, cond, 0);
+ print_gimple_stmt (dump_file, stmt, 0, 0);
fprintf (dump_file, "\nWith known ranges\n");
-
+
FOR_EACH_SSA_TREE_OPERAND (use, stmt, i, SSA_OP_USE)
{
fprintf (dump_file, "\t");
/* Compute the value of the predicate COND by checking the known
ranges of each of its operands.
-
+
Note that we cannot evaluate all the equivalent ranges here
because those ranges may not yet be final and with the current
propagation strategy, we cannot determine when the value ranges
MICO, TRAMP3D and SPEC2000) showed that doing this results in
4 more predicates folded in SPEC. */
sop = false;
- val = vrp_evaluate_conditional_warnv (cond, false, &sop);
+
+ val = vrp_evaluate_conditional_warnv_with_ops (gimple_cond_code (stmt),
+ gimple_cond_lhs (stmt),
+ gimple_cond_rhs (stmt),
+ false, &sop, NULL);
if (val)
{
if (!sop)
- *taken_edge_p = find_taken_edge (bb_for_stmt (stmt), val);
+ *taken_edge_p = find_taken_edge (gimple_bb (stmt), val);
else
{
if (dump_file && (dump_flags & TDF_DETAILS))
return (*taken_edge_p) ? SSA_PROP_INTERESTING : SSA_PROP_VARYING;
}
+/* Searches the case label vector VEC for the index *IDX of the CASE_LABEL
+ that includes the value VAL. The search is restricted to the range
+ [START_IDX, n - 1] where n is the size of VEC.
-/* Searches the case label vector VEC for the index *IDX the CASE_LABEL
- includes the value VAL. The search starts at index START_IDX and
- true is returned if *IDX corresponds to such an index. False is
- returned in case VAL hits the default case label and *IDX in this
- case is the next higher or the next lower case label index. */
+ If there is a CASE_LABEL for VAL, its index is placed in IDX and true is
+ returned.
+
+ If there is no CASE_LABEL for VAL and there is one that is larger than VAL,
+ it is placed in IDX and false is returned.
+
+ If VAL is larger than any CASE_LABEL, n is placed on IDX and false is
+ returned. */
static bool
-find_case_label_index (tree vec, size_t start_idx, tree val, size_t *idx)
+find_case_label_index (gimple stmt, size_t start_idx, tree val, size_t *idx)
{
- size_t n = TREE_VEC_LENGTH (vec);
- size_t low, high, i = start_idx;
+ size_t n = gimple_switch_num_labels (stmt);
+ size_t low, high;
+
+ /* Find case label for minimum of the value range or the next one.
+ At each iteration we are searching in [low, high - 1]. */
- /* Find case label for minimum of the value range or the next one. */
- for (low = start_idx - 1, high = n - 1; high - low > 1; )
+ for (low = start_idx, high = n; high != low; )
{
tree t;
int cmp;
- i = (high + low) / 2;
- t = TREE_VEC_ELT (vec, i);
+ /* Note that i != high, so we never ask for n. */
+ size_t i = (high + low) / 2;
+ t = gimple_switch_label (stmt, i);
/* Cache the result of comparing CASE_LOW and val. */
cmp = tree_int_cst_compare (CASE_LOW (t), val);
- if (cmp > 0)
+ if (cmp == 0)
+ {
+ /* Ranges cannot be empty. */
+ *idx = i;
+ return true;
+ }
+ else if (cmp > 0)
high = i;
else
- low = i;
-
- if (CASE_HIGH (t) == NULL)
- {
- /* A singe-valued case label. */
- if (cmp == 0)
- {
- *idx = i;
- return true;
- }
- }
- else
- {
- /* A case range. We can only handle integer ranges. */
- if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
+ {
+ low = i + 1;
+ if (CASE_HIGH (t) != NULL
+ && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
{
*idx = i;
return true;
}
}
- *idx = i;
+ *idx = high;
return false;
}
+/* Searches the case label vector VEC for the range of CASE_LABELs that is used
+ for values between MIN and MAX. The first index is placed in MIN_IDX. The
+ last index is placed in MAX_IDX. If the range of CASE_LABELs is empty
+ then MAX_IDX < MIN_IDX.
+ Returns true if the default label is not needed. */
+
+static bool
+find_case_label_range (gimple stmt, tree min, tree max, size_t *min_idx,
+ size_t *max_idx)
+{
+ size_t i, j;
+ bool min_take_default = !find_case_label_index (stmt, 1, min, &i);
+ bool max_take_default = !find_case_label_index (stmt, i, max, &j);
+
+ if (i == j
+ && min_take_default
+ && max_take_default)
+ {
+ /* Only the default case label reached.
+ Return an empty range. */
+ *min_idx = 1;
+ *max_idx = 0;
+ return false;
+ }
+ else
+ {
+ bool take_default = min_take_default || max_take_default;
+ tree low, high;
+ size_t k;
+
+ if (max_take_default)
+ j--;
+
+ /* If the case label range is continuous, we do not need
+ the default case label. Verify that. */
+ high = CASE_LOW (gimple_switch_label (stmt, i));
+ if (CASE_HIGH (gimple_switch_label (stmt, i)))
+ high = CASE_HIGH (gimple_switch_label (stmt, i));
+ for (k = i + 1; k <= j; ++k)
+ {
+ low = CASE_LOW (gimple_switch_label (stmt, k));
+ if (!integer_onep (int_const_binop (MINUS_EXPR, low, high, 0)))
+ {
+ take_default = true;
+ break;
+ }
+ high = low;
+ if (CASE_HIGH (gimple_switch_label (stmt, k)))
+ high = CASE_HIGH (gimple_switch_label (stmt, k));
+ }
+
+ *min_idx = i;
+ *max_idx = j;
+ return !take_default;
+ }
+}
+
/* Visit switch statement STMT. If we can determine which edge
will be taken out of STMT's basic block, record it in
*TAKEN_EDGE_P and return SSA_PROP_INTERESTING. Otherwise, return
SSA_PROP_VARYING. */
static enum ssa_prop_result
-vrp_visit_switch_stmt (tree stmt, edge *taken_edge_p)
+vrp_visit_switch_stmt (gimple stmt, edge *taken_edge_p)
{
tree op, val;
value_range_t *vr;
- size_t i = 0, j = 0, n;
- tree vec;
- bool min_take_default, max_take_default;
+ size_t i = 0, j = 0;
+ bool take_default;
*taken_edge_p = NULL;
- op = TREE_OPERAND (stmt, 0);
+ op = gimple_switch_index (stmt);
if (TREE_CODE (op) != SSA_NAME)
return SSA_PROP_VARYING;
return SSA_PROP_VARYING;
/* Find the single edge that is taken from the switch expression. */
- vec = SWITCH_LABELS (stmt);
- n = TREE_VEC_LENGTH (vec);
-
- /* Find case label for minimum of the value range or the next one. */
- min_take_default = !find_case_label_index (vec, 0, vr->min, &i);
-
- /* Find case label for maximum of the value range or the previous one. */
- max_take_default = !find_case_label_index (vec, i, vr->max, &j);
+ take_default = !find_case_label_range (stmt, vr->min, vr->max, &i, &j);
- /* Check if we reach the default label only. */
+ /* Check if the range spans no CASE_LABEL. If so, we only reach the default
+ label */
if (j < i)
- val = TREE_VEC_ELT (vec, n - 1);
- /* Check if we reach exactly one label and not the default label. */
- else if (i == j
- && !min_take_default
- && !max_take_default)
- val = TREE_VEC_ELT (vec, i);
+ {
+ gcc_assert (take_default);
+ val = gimple_switch_default_label (stmt);
+ }
else
{
- /* Check if labels with index i to j are all reaching the same label.
- If we don't hit a single case label only, the default case also has
- to branch to the same label. */
- val = TREE_VEC_ELT (vec, i);
- if (CASE_LABEL (TREE_VEC_ELT (vec, n - 1)) != CASE_LABEL (val))
+ /* Check if labels with index i to j and maybe the default label
+ are all reaching the same label. */
+
+ val = gimple_switch_label (stmt, i);
+ if (take_default
+ && CASE_LABEL (gimple_switch_default_label (stmt))
+ != CASE_LABEL (val))
{
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, " not a single destination for this "
}
for (++i; i <= j; ++i)
{
- if (CASE_LABEL (TREE_VEC_ELT (vec, i)) != CASE_LABEL (val))
+ if (CASE_LABEL (gimple_switch_label (stmt, i)) != CASE_LABEL (val))
{
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, " not a single destination for this "
}
}
- *taken_edge_p = find_edge (bb_for_stmt (stmt),
+ *taken_edge_p = find_edge (gimple_bb (stmt),
label_to_block (CASE_LABEL (val)));
if (dump_file && (dump_flags & TDF_DETAILS))
If STMT produces a varying value, return SSA_PROP_VARYING. */
static enum ssa_prop_result
-vrp_visit_stmt (tree stmt, edge *taken_edge_p, tree *output_p)
+vrp_visit_stmt (gimple stmt, edge *taken_edge_p, tree *output_p)
{
tree def;
ssa_op_iter iter;
- stmt_ann_t ann;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "\nVisiting statement:\n");
- print_generic_stmt (dump_file, stmt, dump_flags);
+ print_gimple_stmt (dump_file, stmt, 0, dump_flags);
fprintf (dump_file, "\n");
}
- ann = stmt_ann (stmt);
- if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT)
+ if (!stmt_interesting_for_vrp (stmt))
+ gcc_assert (stmt_ends_bb_p (stmt));
+ else if (is_gimple_assign (stmt) || is_gimple_call (stmt))
{
- tree rhs = GIMPLE_STMT_OPERAND (stmt, 1);
-
/* In general, assignments with virtual operands are not useful
for deriving ranges, with the obvious exception of calls to
builtin functions. */
- if ((TREE_CODE (rhs) == CALL_EXPR
- && TREE_CODE (CALL_EXPR_FN (rhs)) == ADDR_EXPR
- && DECL_P (TREE_OPERAND (CALL_EXPR_FN (rhs), 0))
- && DECL_IS_BUILTIN (TREE_OPERAND (CALL_EXPR_FN (rhs), 0)))
- || ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
- return vrp_visit_assignment (stmt, output_p);
- }
- else if (TREE_CODE (stmt) == COND_EXPR)
+
+ if ((is_gimple_call (stmt)
+ && gimple_call_fndecl (stmt) != NULL_TREE
+ && DECL_IS_BUILTIN (gimple_call_fndecl (stmt)))
+ || !gimple_vuse (stmt))
+ return vrp_visit_assignment_or_call (stmt, output_p);
+ }
+ else if (gimple_code (stmt) == GIMPLE_COND)
return vrp_visit_cond_stmt (stmt, taken_edge_p);
- else if (TREE_CODE (stmt) == SWITCH_EXPR)
+ else if (gimple_code (stmt) == GIMPLE_SWITCH)
return vrp_visit_switch_stmt (stmt, taken_edge_p);
/* All other statements produce nothing of interest for VRP, so mark
value ranges, set a new range for the LHS of PHI. */
static enum ssa_prop_result
-vrp_visit_phi_node (tree phi)
+vrp_visit_phi_node (gimple phi)
{
- int i;
+ size_t i;
tree lhs = PHI_RESULT (phi);
value_range_t *lhs_vr = get_value_range (lhs);
value_range_t vr_result = { VR_UNDEFINED, NULL_TREE, NULL_TREE, NULL };
int edges, old_edges;
+ struct loop *l;
copy_value_range (&vr_result, lhs_vr);
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "\nVisiting PHI node: ");
- print_generic_expr (dump_file, phi, dump_flags);
+ print_gimple_stmt (dump_file, phi, 0, dump_flags);
}
edges = 0;
- for (i = 0; i < PHI_NUM_ARGS (phi); i++)
+ for (i = 0; i < gimple_phi_num_args (phi); i++)
{
- edge e = PHI_ARG_EDGE (phi, i);
+ edge e = gimple_phi_arg_edge (phi, i);
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file,
"\n Argument #%d (%d -> %d %sexecutable)\n",
- i, e->src->index, e->dest->index,
+ (int) i, e->src->index, e->dest->index,
(e->flags & EDGE_EXECUTABLE) ? "" : "not ");
}
}
}
+ /* If this is a loop PHI node SCEV may known more about its
+ value-range. */
+ if (current_loops
+ && (l = loop_containing_stmt (phi))
+ && l->header == gimple_bb (phi))
+ adjust_range_with_scev (&vr_result, l, phi, lhs);
+
if (vr_result.type == VR_VARYING)
goto varying;
minimums. */
if (cmp_min > 0 || cmp_min < 0)
{
- /* If we will end up with a (-INF, +INF) range, set it
- to VARYING. */
- if (vrp_val_is_max (vr_result.max))
+ /* If we will end up with a (-INF, +INF) range, set it to
+ VARYING. Same if the previous max value was invalid for
+ the type and we'd end up with vr_result.min > vr_result.max. */
+ if (vrp_val_is_max (vr_result.max)
+ || compare_values (TYPE_MIN_VALUE (TREE_TYPE (vr_result.min)),
+ vr_result.max) > 0)
goto varying;
if (!needs_overflow_infinity (TREE_TYPE (vr_result.min))
the previous one, go all the way to +INF. */
if (cmp_max < 0 || cmp_max > 0)
{
- /* If we will end up with a (-INF, +INF) range, set it
- to VARYING. */
- if (vrp_val_is_min (vr_result.min))
+ /* If we will end up with a (-INF, +INF) range, set it to
+ VARYING. Same if the previous min value was invalid for
+ the type and we'd end up with vr_result.max < vr_result.min. */
+ if (vrp_val_is_min (vr_result.min)
+ || compare_values (TYPE_MAX_VALUE (TREE_TYPE (vr_result.max)),
+ vr_result.min) < 0)
goto varying;
if (!needs_overflow_infinity (TREE_TYPE (vr_result.max))
/* If the new range is different than the previous value, keep
iterating. */
if (update_value_range (lhs, &vr_result))
- return SSA_PROP_INTERESTING;
+ {
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "Found new range for ");
+ print_generic_expr (dump_file, lhs, 0);
+ fprintf (dump_file, ": ");
+ dump_value_range (dump_file, &vr_result);
+ fprintf (dump_file, "\n\n");
+ }
+
+ return SSA_PROP_INTERESTING;
+ }
/* Nothing changed, don't add outgoing edges. */
return SSA_PROP_NOT_INTERESTING;
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);
+ if (TYPE_PRECISION (TREE_TYPE (op0)) != 1)
+ {
+ if (TREE_CODE (op0) != SSA_NAME)
+ return false;
+ vr = get_value_range (op0);
+
+ 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. */
+ if (rhs_code != EQ_EXPR
+ && rhs_code != NE_EXPR
+ && rhs_code != TRUTH_XOR_EXPR)
+ return false;
+
+ if (!integer_zerop (op1)
+ && !integer_onep (op1)
+ && !integer_all_onesp (op1))
+ return false;
+
+ /* 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));
+
+ /* Make sure to not sign-extend -1 as a boolean value. */
+ if (need_conversion
+ && !TYPE_UNSIGNED (TREE_TYPE (op0))
+ && TYPE_PRECISION (TREE_TYPE (op0)) == 1)
+ return false;
+
+ 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
-simplify_div_or_mod_using_ranges (tree stmt, tree rhs, enum tree_code rhs_code)
+static bool
+simplify_div_or_mod_using_ranges (gimple stmt)
{
+ enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
tree val = NULL;
- tree op = TREE_OPERAND (rhs, 0);
- value_range_t *vr = get_value_range (TREE_OPERAND (rhs, 0));
+ tree op0 = gimple_assign_rhs1 (stmt);
+ tree op1 = gimple_assign_rhs2 (stmt);
+ value_range_t *vr = get_value_range (gimple_assign_rhs1 (stmt));
- if (TYPE_UNSIGNED (TREE_TYPE (op)))
+ if (TYPE_UNSIGNED (TREE_TYPE (op0)))
{
val = integer_one_node;
}
&& integer_onep (val)
&& issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC))
{
- location_t locus;
+ location_t location;
- if (!EXPR_HAS_LOCATION (stmt))
- locus = input_location;
+ if (!gimple_has_location (stmt))
+ location = input_location;
else
- locus = EXPR_LOCATION (stmt);
- warning (OPT_Wstrict_overflow,
- ("%Hassuming signed overflow does not occur when "
- "simplifying / or %% to >> or &"),
- &locus);
+ location = gimple_location (stmt);
+ warning_at (location, OPT_Wstrict_overflow,
+ "assuming signed overflow does not occur when "
+ "simplifying %</%> or %<%%%> to %<>>%> or %<&%>");
}
}
if (val && integer_onep (val))
{
tree t;
- tree op0 = TREE_OPERAND (rhs, 0);
- tree op1 = TREE_OPERAND (rhs, 1);
if (rhs_code == TRUNC_DIV_EXPR)
{
t = build_int_cst (NULL_TREE, tree_log2 (op1));
- t = build2 (RSHIFT_EXPR, TREE_TYPE (op0), op0, t);
+ gimple_assign_set_rhs_code (stmt, RSHIFT_EXPR);
+ gimple_assign_set_rhs1 (stmt, op0);
+ gimple_assign_set_rhs2 (stmt, t);
}
else
{
t = build_int_cst (TREE_TYPE (op1), 1);
t = int_const_binop (MINUS_EXPR, op1, t, 0);
t = fold_convert (TREE_TYPE (op0), t);
- t = build2 (BIT_AND_EXPR, TREE_TYPE (op0), op0, t);
+
+ gimple_assign_set_rhs_code (stmt, BIT_AND_EXPR);
+ gimple_assign_set_rhs1 (stmt, op0);
+ gimple_assign_set_rhs2 (stmt, t);
}
- GIMPLE_STMT_OPERAND (stmt, 1) = t;
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
-simplify_abs_using_ranges (tree stmt, tree rhs)
+static bool
+simplify_abs_using_ranges (gimple stmt)
{
tree val = NULL;
- tree op = TREE_OPERAND (rhs, 0);
+ tree op = gimple_assign_rhs1 (stmt);
tree type = TREE_TYPE (op);
- value_range_t *vr = get_value_range (TREE_OPERAND (rhs, 0));
+ value_range_t *vr = get_value_range (op);
if (TYPE_UNSIGNED (type))
{
if (val
&& (integer_onep (val) || integer_zerop (val)))
{
- tree t;
-
if (sop && issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC))
{
- location_t locus;
+ location_t location;
- if (!EXPR_HAS_LOCATION (stmt))
- locus = input_location;
+ if (!gimple_has_location (stmt))
+ location = input_location;
else
- locus = EXPR_LOCATION (stmt);
- warning (OPT_Wstrict_overflow,
- ("%Hassuming signed overflow does not occur when "
- "simplifying abs (X) to X or -X"),
- &locus);
+ location = gimple_location (stmt);
+ warning_at (location, OPT_Wstrict_overflow,
+ "assuming signed overflow does not occur when "
+ "simplifying %<abs (X)%> to %<X%> or %<-X%>");
}
+ gimple_assign_set_rhs1 (stmt, op);
if (integer_onep (val))
- t = build1 (NEGATE_EXPR, TREE_TYPE (op), op);
+ gimple_assign_set_rhs_code (stmt, NEGATE_EXPR);
else
- t = op;
-
- GIMPLE_STMT_OPERAND (stmt, 1) = t;
+ 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
value range information we have for op0. */
if (min && max)
{
- if (compare_values (vr->min, min) == -1)
- min = min;
- else
+ if (compare_values (vr->min, min) == 1)
min = vr->min;
- if (compare_values (vr->max, max) == 1)
- max = max;
- else
+ if (compare_values (vr->max, max) == -1)
max = vr->max;
/* If the new min/max values have converged to a single value,
test if the range information indicates only one value can satisfy
the original conditional. */
-static void
-simplify_cond_using_ranges (tree stmt)
+static bool
+simplify_cond_using_ranges (gimple stmt)
{
- tree cond = COND_EXPR_COND (stmt);
- tree op0 = TREE_OPERAND (cond, 0);
- tree op1 = TREE_OPERAND (cond, 1);
- enum tree_code cond_code = TREE_CODE (cond);
+ tree op0 = gimple_cond_lhs (stmt);
+ tree op1 = gimple_cond_rhs (stmt);
+ enum tree_code cond_code = gimple_cond_code (stmt);
if (cond_code != NE_EXPR
&& cond_code != EQ_EXPR
&& is_gimple_min_invariant (op1))
{
value_range_t *vr = get_value_range (op0);
-
+
/* If we have range information for OP0, then we might be
able to simplify this conditional. */
if (vr->type == VR_RANGE)
{
- tree new = test_for_singularity (cond_code, op0, op1, vr);
+ tree new_tree = test_for_singularity (cond_code, op0, op1, vr);
- if (new)
+ if (new_tree)
{
if (dump_file)
{
fprintf (dump_file, "Simplified relational ");
- print_generic_expr (dump_file, cond, 0);
+ print_gimple_stmt (dump_file, stmt, 0, 0);
fprintf (dump_file, " into ");
}
- COND_EXPR_COND (stmt)
- = build2 (EQ_EXPR, boolean_type_node, op0, new);
+ gimple_cond_set_code (stmt, EQ_EXPR);
+ gimple_cond_set_lhs (stmt, op0);
+ gimple_cond_set_rhs (stmt, new_tree);
+
update_stmt (stmt);
if (dump_file)
{
- print_generic_expr (dump_file, COND_EXPR_COND (stmt), 0);
+ print_gimple_stmt (dump_file, stmt, 0, 0);
fprintf (dump_file, "\n");
}
- return;
+ return true;
}
/* Try again after inverting the condition. We only deal
with integral types here, so no need to worry about
issues with inverting FP comparisons. */
cond_code = invert_tree_comparison (cond_code, false);
- new = test_for_singularity (cond_code, op0, op1, vr);
+ new_tree = test_for_singularity (cond_code, op0, op1, vr);
- if (new)
+ if (new_tree)
{
if (dump_file)
{
fprintf (dump_file, "Simplified relational ");
- print_generic_expr (dump_file, cond, 0);
+ print_gimple_stmt (dump_file, stmt, 0, 0);
fprintf (dump_file, " into ");
}
- COND_EXPR_COND (stmt)
- = build2 (NE_EXPR, boolean_type_node, op0, new);
+ gimple_cond_set_code (stmt, NE_EXPR);
+ gimple_cond_set_lhs (stmt, op0);
+ gimple_cond_set_rhs (stmt, new_tree);
+
update_stmt (stmt);
if (dump_file)
{
- print_generic_expr (dump_file, COND_EXPR_COND (stmt), 0);
+ 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 bool
+simplify_switch_using_ranges (gimple stmt)
+{
+ tree op = gimple_switch_index (stmt);
+ value_range_t *vr;
+ bool take_default;
+ edge e;
+ edge_iterator ei;
+ size_t i = 0, j = 0, n, n2;
+ tree vec2;
+ switch_update su;
+
+ if (TREE_CODE (op) == SSA_NAME)
+ {
+ vr = get_value_range (op);
+
+ /* We can only handle integer ranges. */
+ if (vr->type != VR_RANGE
+ || symbolic_range_p (vr))
+ return false;
+
+ /* Find case label for min/max of the value range. */
+ take_default = !find_case_label_range (stmt, vr->min, vr->max, &i, &j);
+ }
+ else if (TREE_CODE (op) == INTEGER_CST)
+ {
+ take_default = !find_case_label_index (stmt, 1, op, &i);
+ if (take_default)
+ {
+ i = 1;
+ j = 0;
+ }
+ else
+ {
+ j = i;
+ }
+ }
+ else
+ return false;
+
+ n = gimple_switch_num_labels (stmt);
+
+ /* Bail out if this is just all edges taken. */
+ if (i == 1
+ && j == n - 1
+ && take_default)
+ return false;
+
+ /* Build a new vector of taken case labels. */
+ vec2 = make_tree_vec (j - i + 1 + (int)take_default);
+ n2 = 0;
+
+ /* Add the default edge, if necessary. */
+ if (take_default)
+ TREE_VEC_ELT (vec2, n2++) = gimple_switch_default_label (stmt);
+
+ for (; i <= j; ++i, ++n2)
+ TREE_VEC_ELT (vec2, n2) = gimple_switch_label (stmt, i);
+
+ /* Mark needed edges. */
+ for (i = 0; i < n2; ++i)
+ {
+ e = find_edge (gimple_bb (stmt),
+ label_to_block (CASE_LABEL (TREE_VEC_ELT (vec2, i))));
+ e->aux = (void *)-1;
+ }
+
+ /* Queue not needed edges for later removal. */
+ FOR_EACH_EDGE (e, ei, gimple_bb (stmt)->succs)
+ {
+ if (e->aux == (void *)-1)
+ {
+ e->aux = NULL;
+ continue;
+ }
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "removing unreachable case label\n");
+ }
+ VEC_safe_push (edge, heap, to_remove_edges, e);
+ e->flags &= ~EDGE_EXECUTABLE;
+ }
+
+ /* And queue an update for the stmt. */
+ 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 (tree stmt)
+static bool
+simplify_stmt_using_ranges (gimple_stmt_iterator *gsi)
{
- if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT)
+ gimple stmt = gsi_stmt (*gsi);
+ if (is_gimple_assign (stmt))
{
- tree rhs = GIMPLE_STMT_OPERAND (stmt, 1);
- enum tree_code rhs_code = TREE_CODE (rhs);
+ 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 (TREE_OPERAND (rhs, 0)))
- && integer_pow2p (TREE_OPERAND (rhs, 1)))
- simplify_div_or_mod_using_ranges (stmt, rhs, rhs_code);
+ 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 (TREE_OPERAND (rhs, 0)) == SSA_NAME
- && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (rhs, 0))))
- simplify_abs_using_ranges (stmt, rhs);
+ 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 (TREE_CODE (stmt) == COND_EXPR
- && COMPARISON_CLASS_P (COND_EXPR_COND (stmt)))
+ else if (gimple_code (stmt) == GIMPLE_COND)
+ return simplify_cond_using_ranges (stmt);
+ else if (gimple_code (stmt) == GIMPLE_SWITCH)
+ return simplify_switch_using_ranges (stmt);
+
+ return false;
+}
+
+/* If the statement pointed by SI has a predicate whose value can be
+ computed using the value range information computed by VRP, compute
+ its value and return true. Otherwise, return false. */
+
+static bool
+fold_predicate_in (gimple_stmt_iterator *si)
+{
+ bool assignment_p = false;
+ tree val;
+ gimple stmt = gsi_stmt (*si);
+
+ if (is_gimple_assign (stmt)
+ && TREE_CODE_CLASS (gimple_assign_rhs_code (stmt)) == tcc_comparison)
+ {
+ assignment_p = true;
+ val = vrp_evaluate_conditional (gimple_assign_rhs_code (stmt),
+ gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt),
+ stmt);
+ }
+ else if (gimple_code (stmt) == GIMPLE_COND)
+ val = vrp_evaluate_conditional (gimple_cond_code (stmt),
+ gimple_cond_lhs (stmt),
+ gimple_cond_rhs (stmt),
+ stmt);
+ else
+ return false;
+
+ if (val)
{
- simplify_cond_using_ranges (stmt);
+ if (assignment_p)
+ val = fold_convert (gimple_expr_type (stmt), val);
+
+ if (dump_file)
+ {
+ fprintf (dump_file, "Folding predicate ");
+ print_gimple_expr (dump_file, stmt, 0, 0);
+ fprintf (dump_file, " to ");
+ print_generic_expr (dump_file, val, 0);
+ fprintf (dump_file, "\n");
+ }
+
+ if (is_gimple_assign (stmt))
+ gimple_assign_set_rhs_from_tree (si, val);
+ else
+ {
+ gcc_assert (gimple_code (stmt) == GIMPLE_COND);
+ if (integer_zerop (val))
+ gimple_cond_make_false (stmt);
+ else if (integer_onep (val))
+ gimple_cond_make_true (stmt);
+ else
+ gcc_unreachable ();
+ }
+
+ return true;
}
+
+ return false;
+}
+
+/* Callback for substitute_and_fold folding the stmt at *SI. */
+
+static bool
+vrp_fold_stmt (gimple_stmt_iterator *si)
+{
+ if (fold_predicate_in (si))
+ return true;
+
+ return simplify_stmt_using_ranges (si);
}
/* Stack of dest,src equivalency pairs that need to be restored after
- each attempt to thread a block's incoming edge to an outgoing edge.
+ each attempt to thread a block's incoming edge to an outgoing edge.
A NULL entry is used to mark the end of pairs which need to be
restored. */
for any overflow warnings. */
static tree
-simplify_stmt_for_jump_threading (tree stmt, tree within_stmt)
+simplify_stmt_for_jump_threading (gimple stmt, gimple within_stmt)
{
/* We only use VRP information to simplify conditionals. This is
overly conservative, but it's unclear if doing more would be
worth the compile time cost. */
- if (TREE_CODE (stmt) != COND_EXPR)
+ if (gimple_code (stmt) != GIMPLE_COND)
return NULL;
- return vrp_evaluate_conditional (COND_EXPR_COND (stmt), within_stmt);
+ return vrp_evaluate_conditional (gimple_cond_code (stmt),
+ gimple_cond_lhs (stmt),
+ gimple_cond_rhs (stmt), within_stmt);
}
/* Blocks which have more than one predecessor and more than
- one successor present jump threading opportunities. ie,
+ one successor present jump threading opportunities, i.e.,
when the block is reached from a specific predecessor, we
may be able to determine which of the outgoing edges will
be traversed. When this optimization applies, we are able
Unlike DOM, we do not iterate VRP if jump threading was successful.
While iterating may expose new opportunities for VRP, it is expected
those opportunities would be very limited and the compile time cost
- to expose those opportunities would be significant.
+ to expose those opportunities would be significant.
As jump threading opportunities are discovered, they are registered
for later realization. */
identify_jump_threads (void)
{
basic_block bb;
- tree dummy;
+ gimple dummy;
+ int i;
+ edge e;
/* Ugh. When substituting values earlier in this pass we can
wipe the dominance information. So rebuild the dominator
recompute it. */
mark_dfs_back_edges ();
+ /* Do not thread across edges we are about to remove. Just marking
+ them as EDGE_DFS_BACK will do. */
+ for (i = 0; VEC_iterate (edge, to_remove_edges, i, e); ++i)
+ e->flags |= EDGE_DFS_BACK;
+
/* Allocate our unwinder stack to unwind any temporary equivalences
that might be recorded. */
stack = VEC_alloc (tree, heap, 20);
/* To avoid lots of silly node creation, we create a single
conditional and just modify it in-place when attempting to
thread jumps. */
- dummy = build2 (EQ_EXPR, boolean_type_node, NULL, NULL);
- dummy = build3 (COND_EXPR, void_type_node, dummy, NULL, NULL);
+ dummy = gimple_build_cond (EQ_EXPR,
+ integer_zero_node, integer_zero_node,
+ NULL, NULL);
/* Walk through all the blocks finding those which present a
potential jump threading opportunity. We could set this up
point in compilation. */
FOR_EACH_BB (bb)
{
- tree last, cond;
+ gimple last;
/* If the generic jump threading code does not find this block
interesting, then there is nothing to do. */
/* We only care about blocks ending in a COND_EXPR. While there
may be some value in handling SWITCH_EXPR here, I doubt it's
terribly important. */
- last = bsi_stmt (bsi_last (bb));
- if (TREE_CODE (last) != COND_EXPR)
+ last = gsi_stmt (gsi_last_bb (bb));
+ if (gimple_code (last) != GIMPLE_COND)
continue;
/* We're basically looking for any kind of conditional with
integral type arguments. */
- cond = COND_EXPR_COND (last);
- if ((TREE_CODE (cond) == SSA_NAME
- && INTEGRAL_TYPE_P (TREE_TYPE (cond)))
- || (COMPARISON_CLASS_P (cond)
- && TREE_CODE (TREE_OPERAND (cond, 0)) == SSA_NAME
- && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (cond, 0)))
- && (TREE_CODE (TREE_OPERAND (cond, 1)) == SSA_NAME
- || is_gimple_min_invariant (TREE_OPERAND (cond, 1)))
- && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (cond, 1)))))
+ if (TREE_CODE (gimple_cond_lhs (last)) == SSA_NAME
+ && INTEGRAL_TYPE_P (TREE_TYPE (gimple_cond_lhs (last)))
+ && (TREE_CODE (gimple_cond_rhs (last)) == SSA_NAME
+ || is_gimple_min_invariant (gimple_cond_rhs (last)))
+ && INTEGRAL_TYPE_P (TREE_TYPE (gimple_cond_rhs (last))))
{
edge_iterator ei;
- edge e;
/* We've got a block with multiple predecessors and multiple
successors which also ends in a suitable conditional. For
if (e->flags & (EDGE_DFS_BACK | EDGE_COMPLEX))
continue;
- thread_across_edge (dummy, e, true,
- &stack,
+ thread_across_edge (dummy, e, true, &stack,
simplify_stmt_for_jump_threading);
}
}
}
/* We may have ended with ranges that have exactly one value. Those
- values can be substituted as any other copy/const propagated
+ values can be substituted as any other const propagated
value using substitute_and_fold. */
single_val_range = XCNEWVEC (prop_value_t, num_ssa_names);
for (i = 0; i < num_ssa_names; i++)
if (vr_value[i]
&& vr_value[i]->type == VR_RANGE
- && vr_value[i]->min == vr_value[i]->max)
+ && vr_value[i]->min == vr_value[i]->max
+ && is_gimple_min_invariant (vr_value[i]->min))
{
single_val_range[i].value = vr_value[i]->min;
do_value_subst_p = true;
single_val_range = NULL;
}
- substitute_and_fold (single_val_range, true);
+ substitute_and_fold (single_val_range, vrp_fold_stmt);
if (warn_array_bounds)
- check_all_array_refs ();
+ check_all_array_refs ();
/* We must identify jump threading opportunities before we release
the datastructures built by VRP. */
vr_phi_edge_counts = NULL;
}
-/* Calculates number of iterations for all loops, to ensure that they are
- cached. */
-
-static void
-record_numbers_of_iterations (void)
-{
- loop_iterator li;
- struct loop *loop;
-
- FOR_EACH_LOOP (li, loop, 0)
- {
- number_of_latch_executions (loop);
- }
-}
/* Main entry point to VRP (Value Range Propagation). This pass is
loosely based on J. R. C. Patterson, ``Accurate Static Branch
4 p_5 = ASSERT_EXPR <p_4, p_4 == q_2>;
5 endif
6 if (q_2)
-
+
In the code above, pointer p_5 has range [q_2, q_2], but from the
code we can also determine that p_5 cannot be NULL and, if q_2 had
a non-varying range, p_5's range should also be compatible with it.
between names so that we can take advantage of information from
multiple ranges when doing final replacement. Note that this
equivalency relation is transitive but not symmetric.
-
+
In the example above, p_5 is equivalent to p_4, q_2 and p_3, but we
cannot assert that q_2 is equivalent to p_5 because q_2 may be used
in contexts where that assertion does not hold (e.g., in line 6).
static unsigned int
execute_vrp (void)
{
+ int i;
+ edge e;
+ switch_update *su;
+
loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS);
rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa);
scev_initialize ();
insert_range_assertions ();
- /* Compute the # of iterations for each loop before we start the VRP
- analysis. The value ranges determined by VRP are used in expression
- simplification, that is also used by the # of iterations analysis.
- However, in the middle of the VRP analysis, the value ranges do not take
- all the possible paths in CFG into account, so they do not have to be
- correct, and the # of iterations analysis can obtain wrong results.
- This is a problem, since the results of the # of iterations analysis
- are cached, so these mistakes would not be corrected when the value
- ranges are corrected. */
- record_numbers_of_iterations ();
+ to_remove_edges = VEC_alloc (edge, heap, 10);
+ to_update_switch_stmts = VEC_alloc (switch_update, heap, 5);
+ threadedge_initialize_values ();
vrp_initialize ();
ssa_propagate (vrp_visit_stmt, vrp_visit_phi_node);
update_ssa (TODO_update_ssa);
finalize_jump_threads ();
+
+ /* Remove dead edges from SWITCH_EXPR optimization. This leaves the
+ CFG in a broken state and requires a cfg_cleanup run. */
+ for (i = 0; VEC_iterate (edge, to_remove_edges, i, e); ++i)
+ remove_edge (e);
+ /* Update SWITCH_EXPR case label vector. */
+ for (i = 0; VEC_iterate (switch_update, to_update_switch_stmts, i, su); ++i)
+ {
+ size_t j;
+ size_t n = TREE_VEC_LENGTH (su->vec);
+ tree label;
+ gimple_switch_set_num_labels (su->stmt, n);
+ for (j = 0; j < n; j++)
+ gimple_switch_set_label (su->stmt, j, TREE_VEC_ELT (su->vec, j));
+ /* As we may have replaced the default label with a regular one
+ make sure to make it a real default label again. This ensures
+ optimal expansion. */
+ label = gimple_switch_default_label (su->stmt);
+ CASE_LOW (label) = NULL_TREE;
+ CASE_HIGH (label) = NULL_TREE;
+ }
+
+ if (VEC_length (edge, to_remove_edges) > 0)
+ free_dominance_info (CDI_DOMINATORS);
+
+ VEC_free (edge, heap, to_remove_edges);
+ VEC_free (switch_update, heap, to_update_switch_stmts);
+ threadedge_finalize_values ();
+
scev_finalize ();
loop_optimizer_finalize ();
-
return 0;
}
NULL, /* next */
0, /* static_pass_number */
TV_TREE_VRP, /* tv_id */
- PROP_ssa | PROP_alias, /* properties_required */
+ PROP_ssa, /* properties_required */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
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