From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ej1-x62a.google.com (mail-ej1-x62a.google.com [IPv6:2a00:1450:4864:20::62a]) by sourceware.org (Postfix) with ESMTPS id 99F733858C52 for ; Fri, 23 Sep 2022 07:04:11 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 99F733858C52 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-ej1-x62a.google.com with SMTP id l14so25940631eja.7 for ; Fri, 23 Sep 2022 00:04:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date; bh=7v3g107zSYHoXQJn+7vpNUXIGb66qwhxo4Q3Bb3x5Gs=; b=OJGribtmK7dy+xcZzYDndkX6/Hfs9NzCDps6/0TwLIQfRwqbos2ftSWMd7LDx8lkLD OCOG+uXh65bvbRz+iHVUwVeAoizpjOLMfMA4Il3sTYXgNjEooY2S8YK1gsiD3oK1aWPS 10upGsRg3wAjjONsHRMTNAbkJBVQNN6P9H1UV1g/B9ckAu14Vo9y+MqP8nIGaBS0ofjr VVBcHgHtLS0/oPx+RWCj6sp9mWGI4hbKjyKfw9V4DAUqgcmT0mYtKdIm/HbAWjZKllWb ZLJeOs6KZ8bKEi79ji7RmQhNW7OwtBPDvL+2OzLN0oA+gX9RwSO/kKbc+B2o9YSADrds 4Rjg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date; bh=7v3g107zSYHoXQJn+7vpNUXIGb66qwhxo4Q3Bb3x5Gs=; b=BIDquqR4w2xIb6P+bi00lDE/807YawMUA4qdtzol98Jv0guyxYIJ/P6NOzUxw1eTJZ xhFAi5VGPceSqHdl/Y5oAwKeNyPFvMPKJSwgsnGSxgGKtgJ/xYf+1mSwPIMRKmfacD+9 5qoj3L5ZslmVM2SgqlW1/3O7LbWLL1p7P2WyX1Cl8LOlh8f7aIcDpGv7kvgFp5HRkUuj AIRifsnPqG7G4zStHN0HEsD++GVHtl12cnuerAkpggGEu5PBH/kQ6obhq8+UQjfv4k2f 21C0MZcC9Jqz3+L4GaLxXgsXy8Th5zCTFvkuXldFKxksOgzx5vBeKoJVnPmCE3UTK3pq DyBQ== X-Gm-Message-State: ACrzQf1sGcaK7dcePilAlMFuJVM710ORNLfMozbdPJAmBa1mZBDmLE6V pySnfV9C8id6KTUw5JHVrOl/TQB6wRJ34sIdnMI= X-Google-Smtp-Source: AMsMyM4KanDX3tO1tqIpj0nDALXcDxas7OIrWr7+lLQy+dPTvtscsoybBtSPCPOKwXM4Ab0BKLPOLMy+xLkkRHs8jAU= X-Received: by 2002:a17:907:7245:b0:782:331b:60f4 with SMTP id ds5-20020a170907724500b00782331b60f4mr5959184ejc.594.1663916650046; Fri, 23 Sep 2022 00:04:10 -0700 (PDT) MIME-Version: 1.0 References: <20220922164911.2566143-1-aldyh@redhat.com> <20220922164911.2566143-2-aldyh@redhat.com> In-Reply-To: <20220922164911.2566143-2-aldyh@redhat.com> From: Richard Biener Date: Fri, 23 Sep 2022 09:03:58 +0200 Message-ID: Subject: Re: [PATCH] frange: drop endpoints to min/max representable numbers for -ffinite-math-only. To: Aldy Hernandez Cc: GCC patches , Jakub Jelinek , Andrew MacLeod Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-8.2 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,GIT_PATCH_0,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Thu, Sep 22, 2022 at 6:49 PM Aldy Hernandez wrote: > > Similarly to how we drop NANs to UNDEFINED when -ffinite-math-only, I > think we can drop the numbers outside of the min/max representable > numbers to the representable number. > > This means the endpoings to VR_VARYING for -ffinite-math-only can now > be the min/max representable, instead of -INF and +INF. > > Saturating in the setter means that the upcoming implementation for > binary operators no longer have to worry about doing the right > thing for -ffinite-math-only. If the range goes outside the limits, > it'll get chopped down. > > How does this look? > > Tested on x86-64 Linux. > > gcc/ChangeLog: > > * range-op-float.cc (build_le): Use vrp_val_*. > (build_lt): Same. > (build_ge): Same. > (build_gt): Same. > * value-range.cc (frange::set): Chop ranges outside of the > representable numbers for -ffinite-math-only. > (frange::normalize_kind): Use vrp_val*. > (frange::verify_range): Same. > (frange::set_nonnegative): Same. > (range_tests_floats): Remove tests that depend on -INF and +INF. > * value-range.h (real_max_representable): Add prototype. > (real_min_representable): Same. > (vrp_val_max): Set max representable number for > -ffinite-math-only. > (vrp_val_min): Same but for min. > (frange::set_varying): Use vrp_val*. > --- > gcc/range-op-float.cc | 12 +++++++---- > gcc/value-range.cc | 46 ++++++++++++++++++++----------------------- > gcc/value-range.h | 30 ++++++++++++++++++++++------ > 3 files changed, 53 insertions(+), 35 deletions(-) > > diff --git a/gcc/range-op-float.cc b/gcc/range-op-float.cc > index 2bd3dc9253f..15ba19c2deb 100644 > --- a/gcc/range-op-float.cc > +++ b/gcc/range-op-float.cc > @@ -232,7 +232,8 @@ build_le (frange &r, tree type, const frange &val) > { > gcc_checking_assert (!val.known_isnan ()); > > - r.set (type, dconstninf, val.upper_bound ()); > + REAL_VALUE_TYPE ninf = *TREE_REAL_CST_PTR (vrp_val_min (type)); > + r.set (type, ninf, val.upper_bound ()); > > // Add both zeros if there's the possibility of zero equality. > frange_add_zeros (r, type); > @@ -257,7 +258,8 @@ build_lt (frange &r, tree type, const frange &val) > return false; > } > // We only support closed intervals. > - r.set (type, dconstninf, val.upper_bound ()); > + REAL_VALUE_TYPE ninf = *TREE_REAL_CST_PTR (vrp_val_min (type)); > + r.set (type, ninf, val.upper_bound ()); > return true; > } > > @@ -268,7 +270,8 @@ build_ge (frange &r, tree type, const frange &val) > { > gcc_checking_assert (!val.known_isnan ()); > > - r.set (type, val.lower_bound (), dconstinf); > + REAL_VALUE_TYPE inf = *TREE_REAL_CST_PTR (vrp_val_max (type)); > + r.set (type, val.lower_bound (), inf); > > // Add both zeros if there's the possibility of zero equality. > frange_add_zeros (r, type); > @@ -294,7 +297,8 @@ build_gt (frange &r, tree type, const frange &val) > } > > // We only support closed intervals. > - r.set (type, val.lower_bound (), dconstinf); > + REAL_VALUE_TYPE inf = *TREE_REAL_CST_PTR (vrp_val_max (type)); > + r.set (type, val.lower_bound (), inf); > return true; > } > > diff --git a/gcc/value-range.cc b/gcc/value-range.cc > index 7e8028eced2..e57d60e1bac 100644 > --- a/gcc/value-range.cc > +++ b/gcc/value-range.cc > @@ -338,6 +338,18 @@ frange::set (tree min, tree max, value_range_kind kind) > m_neg_nan = false; > } > > + // For -ffinite-math-only we can drop ranges outside the > + // representable numbers to min/max for the type. > + if (flag_finite_math_only) > + { > + REAL_VALUE_TYPE min_repr = *TREE_REAL_CST_PTR (vrp_val_min (m_type)); > + REAL_VALUE_TYPE max_repr = *TREE_REAL_CST_PTR (vrp_val_max (m_type)); > + if (real_less (&m_min, &min_repr)) > + m_min = min_repr; > + if (real_less (&max_repr, &m_max)) > + m_max = max_repr; I think you want to re-formulate that in terms of real_isinf() and change those to the max representable values. > + } > + > // Check for swapped ranges. > gcc_checking_assert (tree_compare (LE_EXPR, min, max)); > > @@ -371,8 +383,8 @@ bool > frange::normalize_kind () > { > if (m_kind == VR_RANGE > - && real_isinf (&m_min, 1) > - && real_isinf (&m_max, 0)) > + && vrp_val_is_min (build_real (m_type, m_min)) > + && vrp_val_is_max (build_real (m_type, m_max))) I think this suggests that keeping +-Inf might be the better choice. At least you want to change vrp_val_is_min/max to take a REAL_VALUE_TYPE to avoid building four tree nodes for just this compare? > { > if (m_pos_nan && m_neg_nan) > { > @@ -385,8 +397,8 @@ frange::normalize_kind () > if (!m_pos_nan || !m_neg_nan) > { > m_kind = VR_RANGE; > - m_min = dconstninf; > - m_max = dconstinf; > + m_min = *TREE_REAL_CST_PTR (vrp_val_min (m_type)); > + m_max = *TREE_REAL_CST_PTR (vrp_val_max (m_type)); > return true; > } > } > @@ -706,8 +718,8 @@ frange::verify_range () > case VR_VARYING: > gcc_checking_assert (m_type); > gcc_checking_assert (m_pos_nan && m_neg_nan); > - gcc_checking_assert (real_isinf (&m_min, 1)); > - gcc_checking_assert (real_isinf (&m_max, 0)); > + gcc_checking_assert (vrp_val_is_min (build_real (m_type, m_min))); > + gcc_checking_assert (vrp_val_is_max (build_real (m_type, m_max))); > return; > case VR_RANGE: > gcc_checking_assert (m_type); > @@ -732,7 +744,8 @@ frange::verify_range () > // If all the properties are clear, we better not span the entire > // domain, because that would make us varying. > if (m_pos_nan && m_neg_nan) > - gcc_checking_assert (!real_isinf (&m_min, 1) || !real_isinf (&m_max, 0)); > + gcc_checking_assert (!vrp_val_is_min (build_real (m_type, m_min)) > + || !vrp_val_is_max (build_real (m_type, m_max))); > } > > // We can't do much with nonzeros yet. > @@ -779,7 +792,7 @@ frange::zero_p () const > void > frange::set_nonnegative (tree type) > { > - set (type, dconst0, dconstinf); > + set (type, dconst0, *TREE_REAL_CST_PTR (vrp_val_max (type))); > > // Set +NAN as the only possibility. > if (HONOR_NANS (type)) > @@ -3886,23 +3899,6 @@ range_tests_floats () > r0.clear_nan (); > ASSERT_FALSE (r0.varying_p ()); > > - // The endpoints of a VARYING are +-INF. > - r0.set_varying (float_type_node); > - ASSERT_TRUE (real_identical (&r0.lower_bound (), &dconstninf)); > - ASSERT_TRUE (real_identical (&r0.upper_bound (), &dconstinf)); > - > - // The maximum representable range for a type is still a subset of VARYING. > - REAL_VALUE_TYPE q, r; > - real_min_representable (&q, float_type_node); > - real_max_representable (&r, float_type_node); > - r0 = frange (float_type_node, q, r); > - // r0 is not a varying, because it does not include -INF/+INF. > - ASSERT_FALSE (r0.varying_p ()); > - // The upper bound of r0 must be less than +INF. > - ASSERT_TRUE (real_less (&r0.upper_bound (), &dconstinf)); > - // The lower bound of r0 must be greater than -INF. > - ASSERT_TRUE (real_less (&dconstninf, &r0.lower_bound ())); > - > // For most architectures, where float and double are different > // sizes, having the same endpoints does not necessarily mean the > // ranges are equal. > diff --git a/gcc/value-range.h b/gcc/value-range.h > index 3668b331187..74879b76b40 100644 > --- a/gcc/value-range.h > +++ b/gcc/value-range.h > @@ -593,6 +593,8 @@ extern void dump_value_range (FILE *, const vrange *); > extern bool vrp_val_is_min (const_tree); > extern bool vrp_val_is_max (const_tree); > extern bool vrp_operand_equal_p (const_tree, const_tree); > +inline void real_max_representable (REAL_VALUE_TYPE *r, const_tree type); > +inline void real_min_representable (REAL_VALUE_TYPE *r, const_tree type); > > inline value_range_kind > vrange::kind () const > @@ -1009,7 +1011,15 @@ vrp_val_max (const_tree type) > return wide_int_to_tree (const_cast (type), max); > } > if (frange::supports_p (type)) > - return build_real (const_cast (type), dconstinf); > + { > + if (flag_finite_math_only) > + { > + REAL_VALUE_TYPE r; > + real_max_representable (&r, type); > + return build_real (const_cast (type), r); > + } > + return build_real (const_cast (type), dconstinf); Overall there's too many places affected IMHO. The above also shows we're building trees a lot - note that REAL_CST are _not_ shared, so each time you call build_real a new REAL_CST tree node is allocated (and later GCed if no longer used). I thought vrp_val_min/max are legacy by now ... That said, using trees for the range representation might not be the very best thing to do, it's unnecessarily wrapping things. > + } > return NULL_TREE; > } > > @@ -1023,7 +1033,15 @@ vrp_val_min (const_tree type) > if (POINTER_TYPE_P (type)) > return build_zero_cst (const_cast (type)); > if (frange::supports_p (type)) > - return build_real (const_cast (type), dconstninf); > + { > + if (flag_finite_math_only) > + { > + REAL_VALUE_TYPE r; > + real_min_representable (&r, type); > + return build_real (const_cast (type), r); > + } > + return build_real (const_cast (type), dconstninf); > + } > return NULL_TREE; > } > > @@ -1073,8 +1091,8 @@ frange::set_varying (tree type) > { > m_kind = VR_VARYING; > m_type = type; > - m_min = dconstninf; > - m_max = dconstinf; > + m_min = *TREE_REAL_CST_PTR (vrp_val_min (type)); > + m_max = *TREE_REAL_CST_PTR (vrp_val_max (type)); > m_pos_nan = true; > m_neg_nan = true; > } > @@ -1133,7 +1151,7 @@ frange::clear_nan () > // Set R to maximum representable value for TYPE. > > inline void > -real_max_representable (REAL_VALUE_TYPE *r, tree type) > +real_max_representable (REAL_VALUE_TYPE *r, const_tree type) > { > char buf[128]; > get_max_float (REAL_MODE_FORMAT (TYPE_MODE (type)), > @@ -1145,7 +1163,7 @@ real_max_representable (REAL_VALUE_TYPE *r, tree type) > // Set R to minimum representable value for TYPE. > > inline void > -real_min_representable (REAL_VALUE_TYPE *r, tree type) > +real_min_representable (REAL_VALUE_TYPE *r, const_tree type) > { > real_max_representable (r, type); > *r = real_value_negate (r); > -- > 2.37.1 >