+/* Helper to extract a value-range *VR for a multiplicative operation
+ *VR0 CODE *VR1. */
+
+static void
+extract_range_from_multiplicative_op_1 (value_range_t *vr,
+ enum tree_code code,
+ value_range_t *vr0, value_range_t *vr1)
+{
+ enum value_range_type type;
+ tree val[4];
+ size_t i;
+ tree min, max;
+ bool sop;
+ int cmp;
+
+ /* Multiplications, divisions and shifts 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
+ maximum values for the new range. One approach is to figure
+ out all the variations of range combinations and do the
+ operations.
+
+ However, this involves several calls to compare_values and it
+ is pretty convoluted. It's simpler to do the 4 operations
+ (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. */
+ gcc_assert (code == MULT_EXPR
+ || code == TRUNC_DIV_EXPR
+ || code == FLOOR_DIV_EXPR
+ || code == CEIL_DIV_EXPR
+ || code == EXACT_DIV_EXPR
+ || code == ROUND_DIV_EXPR
+ || code == RSHIFT_EXPR);
+ gcc_assert ((vr0->type == VR_RANGE
+ || (code == MULT_EXPR && vr0->type == VR_ANTI_RANGE))
+ && vr0->type == vr1->type);
+
+ type = vr0->type;
+
+ /* 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;
+ }
+
+ 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;
+ }
+
+ 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;
+ }
+
+ /* 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 (val[i])
+ {
+ 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], max) == 1)
+ max = val[i];
+ }
+ }
+
+ /* If either MIN or MAX overflowed, then set the resulting range to
+ VARYING. But we do accept an overflow infinity
+ representation. */
+ if (min == NULL_TREE
+ || !is_gimple_min_invariant (min)
+ || (TREE_OVERFLOW (min) && !is_overflow_infinity (min))
+ || max == NULL_TREE
+ || !is_gimple_min_invariant (max)
+ || (TREE_OVERFLOW (max) && !is_overflow_infinity (max)))
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
+
+ /* We punt if:
+ 1) [-INF, +INF]
+ 2) [-INF, +-INF(OVF)]
+ 3) [+-INF(OVF), +INF]
+ 4) [+-INF(OVF), +-INF(OVF)]
+ We learn nothing when we have INF and INF(OVF) on both sides.
+ Note that we do accept [-INF, -INF] and [+INF, +INF] without
+ overflow. */
+ if ((vrp_val_is_min (min) || is_overflow_infinity (min))
+ && (vrp_val_is_max (max) || is_overflow_infinity (max)))
+ {
+ set_value_range_to_varying (vr);
+ return;
+ }
+
+ cmp = compare_values (min, max);
+ if (cmp == -2 || cmp == 1)
+ {
+ /* If the new range has its limits swapped around (MIN > MAX),
+ then the operation caused one of them to wrap around, mark
+ the new range VARYING. */
+ set_value_range_to_varying (vr);
+ }
+ else
+ set_value_range (vr, type, min, max, NULL);
+}