From 3dfeda095bd43c011fdc3834b9cec39bb9a73a1f Mon Sep 17 00:00:00 2001 From: Aldy Hernandez Date: Fri, 14 Oct 2022 12:08:11 +0200 Subject: [PATCH] Check rvc_normal in real_isdenormal. [-Inf, -Inf] is being flushed to [-Inf, -0.0] because real_isdenormal is being overly pessimistic. It is missing a check for rvc_normal. This doesn't cause problems in real.cc because all uses of real_isdenormal are already on the rvc_normal path. The uses in value-range.cc however, are not. This patch adds a check for rvc_normal. gcc/ChangeLog: * real.h (real_isdenormal): Check rvc_normal. * value-range.cc (range_tests_floats): New test. --- gcc/real.h | 2 +- gcc/value-range.cc | 5 +++++ 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/gcc/real.h b/gcc/real.h index f9528d7..306e959 100644 --- a/gcc/real.h +++ b/gcc/real.h @@ -290,7 +290,7 @@ extern bool real_issignaling_nan (const REAL_VALUE_TYPE *); inline bool real_isdenormal (const REAL_VALUE_TYPE *r) { - return (r->sig[SIGSZ-1] & SIG_MSB) == 0; + return r->cl == rvc_normal && (r->sig[SIGSZ-1] & SIG_MSB) == 0; } /* Determine whether a floating-point value X is finite. */ diff --git a/gcc/value-range.cc b/gcc/value-range.cc index 6b4f3dd..ee15eb3 100644 --- a/gcc/value-range.cc +++ b/gcc/value-range.cc @@ -4014,6 +4014,11 @@ range_tests_floats () r1.clear_nan (); r0.intersect (r1); ASSERT_TRUE (r0.undefined_p ()); + + // Make sure [-Inf, -Inf] doesn't get normalized. + r0 = frange_float ("-Inf", "-Inf"); + ASSERT_TRUE (real_isinf (&r0.lower_bound (), true)); + ASSERT_TRUE (real_isinf (&r0.upper_bound (), true)); } void -- 2.7.4