diff options
Diffstat (limited to 'gcc/range-op-float.cc')
| -rw-r--r-- | gcc/range-op-float.cc | 79 |
1 files changed, 58 insertions, 21 deletions
diff --git a/gcc/range-op-float.cc b/gcc/range-op-float.cc index ff9fe31..ca41136 100644 --- a/gcc/range-op-float.cc +++ b/gcc/range-op-float.cc @@ -150,6 +150,18 @@ range_operator_float::op1_op2_relation (const irange &lhs ATTRIBUTE_UNUSED) cons return VREL_VARYING; } +// Set R to [NAN, NAN]. + +static inline void +frange_set_nan (frange &r, tree type) +{ + REAL_VALUE_TYPE rv; + bool res = real_nan (&rv, "", 1, TYPE_MODE (type)); + if (flag_checking) + gcc_assert (res); + r.set (type, rv, rv); +} + // Return TRUE if OP1 and OP2 are known to be free of NANs. static inline bool @@ -178,6 +190,40 @@ frelop_early_resolve (irange &r, tree type, && relop_early_resolve (r, type, op1, op2, rel, my_rel)); } +// Crop R to [-INF, MAX] where MAX is the maximum representable number +// for TYPE. + +static inline void +frange_drop_inf (frange &r, tree type) +{ + // FIXME: build_real() bails on decimal float modes when called with + // a max representable endpoint. + if (DECIMAL_FLOAT_MODE_P (TYPE_MODE (type))) + return; + + REAL_VALUE_TYPE max; + real_max_representable (&max, type); + frange tmp (type, r.lower_bound (), max); + r.intersect (tmp); +} + +// Crop R to [MIN, +INF] where MIN is the minimum representable number +// for TYPE. + +static inline void +frange_drop_ninf (frange &r, tree type) +{ + // FIXME: build_real() bails on decimal float modes when called with + // a max representable endpoint. + if (DECIMAL_FLOAT_MODE_P (TYPE_MODE (type))) + return; + + REAL_VALUE_TYPE min; + real_min_representable (&min, type); + frange tmp (type, min, r.upper_bound ()); + r.intersect (tmp); +} + // Default implementation of fold_range for relational operators. // This amounts to passing on any known relations from the oracle, iff // we know the operands are not NAN or -ffinite-math-only holds. @@ -252,21 +298,8 @@ foperator_equal::op1_range (frange &r, tree type, switch (get_bool_state (r, lhs, type)) { case BRS_TRUE: - if (HONOR_SIGNED_ZEROS (type) - && op2.contains_p (build_zero_cst (type))) - { - // With signed zeros, x == -0.0 does not mean we can replace - // x with -0.0, because x may be either +0.0 or -0.0. - r.set_varying (type); - } - else - { - // If it's true, the result is the same as OP2. - // - // If the range does not actually contain zeros, this should - // always be OK. - r = op2; - } + // If it's true, the result is the same as OP2. + r = op2; // The TRUE side of op1 == op2 implies op1 is !NAN. r.set_nan (fp_prop::NO); break; @@ -275,7 +308,7 @@ foperator_equal::op1_range (frange &r, tree type, r.set_varying (type); // The FALSE side of op1 == op1 implies op1 is a NAN. if (rel == VREL_EQ) - r.set_nan (fp_prop::YES); + frange_set_nan (r, type); break; default: @@ -365,7 +398,8 @@ foperator_lt::op1_range (frange &r, r.set_varying (type); // The TRUE side of op1 < op2 implies op1 is !NAN and !INF. r.set_nan (fp_prop::NO); - r.set_inf (fp_prop::NO); + // x < y implies x is not +INF. + frange_drop_inf (r, type); break; case BRS_FALSE: @@ -391,7 +425,8 @@ foperator_lt::op2_range (frange &r, r.set_varying (type); // The TRUE side of op1 < op2 implies op2 is !NAN and !NINF. r.set_nan (fp_prop::NO); - r.set_ninf (fp_prop::NO); + // x < y implies y is not -INF. + frange_drop_ninf (r, type); break; case BRS_FALSE: @@ -493,7 +528,8 @@ foperator_gt::op1_range (frange &r, r.set_varying (type); // The TRUE side of op1 > op2 implies op1 is !NAN and !NINF. r.set_nan (fp_prop::NO); - r.set_ninf (fp_prop::NO); + // x > y implies x is not -INF. + frange_drop_ninf (r, type); break; case BRS_FALSE: @@ -519,7 +555,8 @@ foperator_gt::op2_range (frange &r, r.set_varying (type); // The TRUE side of op1 > op2 implies op2 is !NAN and !INF. r.set_nan (fp_prop::NO); - r.set_inf (fp_prop::NO); + // x > y implies y is not +INF. + frange_drop_inf (r, type); break; case BRS_FALSE: @@ -636,7 +673,7 @@ foperator_unordered::op1_range (frange &r, tree type, // Since at least one operand must be NAN, if one of them is // not, the other must be. if (op2.get_nan ().no_p ()) - r.set_nan (fp_prop::YES); + frange_set_nan (r, type); break; case BRS_FALSE: |