Richard Biener <rguent...@suse.de> writes:
>> @@ -812,33 +997,80 @@ split_constant_offset_1 (tree type, tree op0, enum
>> tree_code code, tree op1,
>> }
>> }
>>
>> -/* Expresses EXP as VAR + OFF, where off is a constant. The type of OFF
>> - will be ssizetype. */
>> +/* If EXP has pointer type, try to express it as:
>> +
>> + POINTER_PLUS <*VAR, (sizetype) *OFF>
>> +
>> + where:
>> +
>> + - *VAR has the same type as EXP
>> + - *OFF is a constant of type ssizetype.
>> +
>> + If EXP has an integral type, try to express (sizetype) EXP as:
>> +
>> + *VAR + (sizetype) *OFF
>> +
>> + where:
>> +
>> + - *VAR has type sizetype
>> + - *OFF is a constant of type ssizetype.
>> +
>> + If EXP_RANGE is nonnull, set it to the range of EXP.
>> +
>> + CACHE caches {*VAR, *OFF} pairs for SSA names that we've previously
>> + visited. LIMIT counts down the number of SSA names that we are
>> + allowed to process before giving up. */
>>
>> static void
>> -split_constant_offset (tree exp, tree *var, tree *off,
>> +split_constant_offset (tree exp, tree *var, tree *off, value_range
>> *exp_range,
>> hash_map<tree, std::pair<tree, tree> > &cache,
>> unsigned *limit)
>> {
>> - tree type = TREE_TYPE (exp), op0, op1, e, o;
>> + tree type = TREE_TYPE (exp), op0, op1;
>> enum tree_code code;
>>
>> - *var = exp;
>> - *off = ssize_int (0);
>> + code = TREE_CODE (exp);
>> + if (exp_range)
>> + {
>> + *exp_range = type;
>> + if (code == SSA_NAME)
>> + {
>> + wide_int var_min, var_max;
>> + value_range_kind vr_kind = get_range_info (exp, &var_min, &var_max);
>> + wide_int var_nonzero = get_nonzero_bits (exp);
>> + vr_kind = intersect_range_with_nonzero_bits (vr_kind,
>> + &var_min, &var_max,
>> + var_nonzero,
>> + TYPE_SIGN (type));
>> + if (vr_kind == VR_RANGE)
>> + *exp_range = value_range (type, var_min, var_max);
>> + }
>> + }
>>
>> - if (tree_is_chrec (exp)
>> - || get_gimple_rhs_class (TREE_CODE (exp)) == GIMPLE_TERNARY_RHS)
>> - return;
>> + if (!tree_is_chrec (exp)
>> + && get_gimple_rhs_class (TREE_CODE (exp)) != GIMPLE_TERNARY_RHS)
>> + {
>> + extract_ops_from_tree (exp, &code, &op0, &op1);
>> + if (split_constant_offset_1 (type, op0, code, op1, var, off,
>> + exp_range, cache, limit))
>> + return;
>> + }
>>
>> - code = TREE_CODE (exp);
>> - extract_ops_from_tree (exp, &code, &op0, &op1);
>> - if (split_constant_offset_1 (type, op0, code, op1, &e, &o, cache, limit))
>> + *var = exp;
>> + if (INTEGRAL_TYPE_P (type))
>> + *var = fold_convert (sizetype, *var);
>> + *off = ssize_int (0);
>> + if (exp_range && code != SSA_NAME)
>> {
>> - *var = e;
>> - *off = o;
>> + wide_int var_min, var_max;
>> + if (determine_value_range (exp, &var_min, &var_max) == VR_RANGE)
>> + *exp_range = value_range (type, var_min, var_max);
>
> So this call is only for the case the recursion failed, otherwise
> we build exp_range during the recursive call, correct?
Yeah, that's right.
> The patch is OK.
Thanks. For the record, now also tested on x86_64-linux-gnu.
I'm not sure what to do about backports though. It seems a bit
invasive for GCC 8 and 9 at least (PR95396).
Richard
