From 4f32e08f7317c52ed72ee48447cb4dd5d68a5c28 Mon Sep 17 00:00:00 2001 From: Aldy Hernandez Date: Mon, 5 Sep 2022 15:41:39 +0200 Subject: [PATCH] Disable decimal floating point in frange. As Jakub mentioned in the PR, because many numbers have multiple possible representations, we can't reliably return true for singleton_p. For that matter, we may not be capable of modeling them just yet. Disabling them until someone with DFP knowledge can opine or extend frange. PR middle-end/106831 gcc/ChangeLog: * value-range.h (frange::supports_p): Disable decimal floats. * range-op-float.cc (frange_drop_inf): Remove DECIMAL_FLOAT_MODE_P check. (frange_drop_ninf): Same. --- gcc/range-op-float.cc | 10 ---------- gcc/value-range.h | 5 ++++- 2 files changed, 4 insertions(+), 11 deletions(-) diff --git a/gcc/range-op-float.cc b/gcc/range-op-float.cc index 7301e5a060b..050f07a9867 100644 --- a/gcc/range-op-float.cc +++ b/gcc/range-op-float.cc @@ -204,11 +204,6 @@ frelop_early_resolve (irange &r, tree 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); @@ -221,11 +216,6 @@ frange_drop_inf (frange &r, tree 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 ()); diff --git a/gcc/value-range.h b/gcc/value-range.h index bc00f3d5b08..645dc76c33a 100644 --- a/gcc/value-range.h +++ b/gcc/value-range.h @@ -338,7 +338,10 @@ public: value_range_kind = VR_RANGE); static bool supports_p (const_tree type) { - return SCALAR_FLOAT_TYPE_P (type); + // ?? Decimal floats can have multiple representations for the + // same number. Supporting them may be as simple as just + // disabling them in singleton_p. No clue. + return SCALAR_FLOAT_TYPE_P (type) && !DECIMAL_FLOAT_TYPE_P (type); } virtual tree type () const override; virtual void set (tree, tree, value_range_kind = VR_RANGE) override; -- 2.37.1