From e98e63404c6b3057ac0f0ff4fe871cd19a1aacb4 Mon Sep 17 00:00:00 2001
From: Segher Boessenkool <segher@kernel.crashing.org>
Date: Wed, 17 May 2017 23:57:23 +0200
Subject: [PATCH] Fix comparison of decimal float zeroes (PR80692)
Decimal float negative zero should compare equal to positive zero.
Decimal float zeroes are encoded as value class "normal" (in real.c);
they need to be handled specially, but in this one case that does not
yet happen. This fixes it.
PR middle-end/80692
* real.c (do_compare): Give decimal_do_compare preference over
comparing just the signs.
gcc/testsuite/
PR middle-end/80692
* gcc.c-torture/execute/pr80692.c: New testcase.
From-SVN: r248174
---
gcc/ChangeLog | 6 ++++++
gcc/real.c | 6 +++---
gcc/testsuite/ChangeLog | 5 +++++
gcc/testsuite/gcc.c-torture/execute/pr80692.c | 13 +++++++++++++
4 files changed, 27 insertions(+), 3 deletions(-)
create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr80692.c
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 068ddd90d1e7..f9a143068a0f 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2017-05-17 Segher Boessenkool <segher@kernel.crashing.org>
+
+ PR middle-end/80692
+ * real.c (do_compare): Give decimal_do_compare preference over
+ comparing just the signs.
+
2017-05-17 Uros Bizjak <ubizjak@gmail.com>
* doc/md.texi (Canonicalization of Instructions): Describe the
diff --git a/gcc/real.c b/gcc/real.c
index 97452a9701ed..a5671b2865bd 100644
--- a/gcc/real.c
+++ b/gcc/real.c
@@ -960,12 +960,12 @@ do_compare (const REAL_VALUE_TYPE *a, const REAL_VALUE_TYPE *b,
gcc_unreachable ();
}
- if (a->sign != b->sign)
- return -a->sign - -b->sign;
-
if (a->decimal || b->decimal)
return decimal_do_compare (a, b, nan_result);
+ if (a->sign != b->sign)
+ return -a->sign - -b->sign;
+
if (REAL_EXP (a) > REAL_EXP (b))
ret = 1;
else if (REAL_EXP (a) < REAL_EXP (b))
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9549f609cf04..7b38a5233f99 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2017-05-17 Segher Boessenkool <segher@kernel.crashing.org>
+
+ PR middle-end/80692
+ * gcc.c-torture/execute/pr80692.c: New testcase.
+
2017-05-17 Jerry DeLisle <jvdelisle@gcc.gnu.org>
PR libgfortran/80741
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr80692.c b/gcc/testsuite/gcc.c-torture/execute/pr80692.c
new file mode 100644
index 000000000000..e653c71c9130
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr80692.c
@@ -0,0 +1,13 @@
+/* { dg-require-effective-target dfp } */
+
+int main () {
+ _Decimal64 d64 = -0.DD;
+
+ if (d64 != 0.DD)
+ __builtin_abort ();
+
+ if (d64 != -0.DD)
+ __builtin_abort ();
+
+ return 0;
+}
--
GitLab