On Wed, Jan 23, 2019 at 12:50 PM Joseph Myers <jos...@codesourcery.com> wrote:
>
> On Wed, 23 Jan 2019, H.J. Lu wrote:
>
> > + fesetround (FE_DOWNWARD);
> > + float fs = s128;
> > + if (fs != -0x1p+127)
> > + abort ();
> > + double ds = s128;
> > + if (ds != -0x1p+127)
> > + abort ();
>
> This definitely needs #ifdef FE_DOWNWARD; even just limited to glibc
> configurations, there are soft-float 64-bit configurations with no support
> for rounding modes other than to-nearest. Likewise for the other tests
> using rounding modes other than FE_TONEAREST. OK with that change.
>
> It's possible it will turn out a new effective-target is needed for fenv.h
> support, if there are still configurations people are testing with that
> lack fenv.h at all.
>
This is the patch I am checking in.
Thanks.
--
H.J.
From ecb5e6357cff988a6e34aed324f13b777af82deb Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.to...@gmail.com>
Date: Tue, 22 Jan 2019 18:55:35 -0800
Subject: [PATCH] libgcc2.c: Correct DI/TI -> SF/DF conversions
FSTYPE FUNC (DWtype u) in libgcc2.c, which converts DI/TI to SF/DF, has
/* No leading bits means u == minimum. */
if (count == 0)
return -(Wtype_MAXp1_F * (Wtype_MAXp1_F / 2));
in the third case (where actually count == 0 only means the high part is
minimum). It should be:
/* No leading bits means u == minimum. */
if (count == 0)
return Wtype_MAXp1_F * (FSTYPE) (hi | ((UWtype) u != 0));
instead.
gcc/testsuite/
2019-01-23 H.J. Lu <hongjiu...@intel.com>
PR libgcc/88931
* gcc.dg/torture/fp-int-convert-timode-1.c: New test.
* gcc.dg/torture/fp-int-convert-timode-2.c: Likewise.
* gcc.dg/torture/fp-int-convert-timode-3.c: Likewise.
* gcc.dg/torture/fp-int-convert-timode-4.c: Likewise.
libgcc/
2019-01-23 Joseph Myers <jos...@codesourcery.com>
PR libgcc/88931
* libgcc2.c (FSTYPE FUNC (DWtype u)): Correct no leading bits
case.
---
.../gcc.dg/torture/fp-int-convert-timode-1.c | 25 +++++++++++++++++
.../gcc.dg/torture/fp-int-convert-timode-2.c | 27 +++++++++++++++++++
.../gcc.dg/torture/fp-int-convert-timode-3.c | 27 +++++++++++++++++++
.../gcc.dg/torture/fp-int-convert-timode-4.c | 27 +++++++++++++++++++
libgcc/libgcc2.c | 2 +-
5 files changed, 107 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-1.c
create mode 100644 gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-2.c
create mode 100644 gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-3.c
create mode 100644 gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-4.c
diff --git a/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-1.c b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-1.c
new file mode 100644
index 00000000000..d6454fada72
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-1.c
@@ -0,0 +1,25 @@
+/* Test for correct rounding of conversions from __int128 to
+ float. */
+/* { dg-do run } */
+/* { dg-require-effective-target int128 } */
+/* { dg-options "-frounding-math" } */
+
+#include <fenv.h>
+#include <stdlib.h>
+
+int
+main (void)
+{
+ volatile unsigned long long h = 0x8000000000000000LL;
+ volatile unsigned long long l = 0xdLL;
+ volatile unsigned __int128 u128 = (((unsigned __int128) h) << 64) | l;
+ volatile __int128 s128 = u128;
+ fesetround (FE_TONEAREST);
+ float fs = s128;
+ if (fs != -0x1p+127)
+ abort ();
+ double ds = s128;
+ if (ds != -0x1p+127)
+ abort ();
+ exit (0);
+}
diff --git a/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-2.c b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-2.c
new file mode 100644
index 00000000000..dbfa481b4fb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-2.c
@@ -0,0 +1,27 @@
+/* Test for correct rounding of conversions from __int128 to
+ float. */
+/* { dg-do run } */
+/* { dg-require-effective-target int128 } */
+/* { dg-options "-frounding-math" } */
+
+#include <fenv.h>
+#include <stdlib.h>
+
+int
+main (void)
+{
+#ifdef FE_DOWNWARD
+ volatile unsigned long long h = 0x8000000000000000LL;
+ volatile unsigned long long l = 0xdLL;
+ volatile unsigned __int128 u128 = (((unsigned __int128) h) << 64) | l;
+ volatile __int128 s128 = u128;
+ fesetround (FE_DOWNWARD);
+ float fs = s128;
+ if (fs != -0x1p+127)
+ abort ();
+ double ds = s128;
+ if (ds != -0x1p+127)
+ abort ();
+#endif
+ exit (0);
+}
diff --git a/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-3.c b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-3.c
new file mode 100644
index 00000000000..63a305ec3c2
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-3.c
@@ -0,0 +1,27 @@
+/* Test for correct rounding of conversions from __int128 to
+ float. */
+/* { dg-do run } */
+/* { dg-require-effective-target int128 } */
+/* { dg-options "-frounding-math" } */
+
+#include <fenv.h>
+#include <stdlib.h>
+
+int
+main (void)
+{
+#ifdef FE_UPWARD
+ volatile unsigned long long h = 0x8000000000000000LL;
+ volatile unsigned long long l = 0xdLL;
+ volatile unsigned __int128 u128 = (((unsigned __int128) h) << 64) | l;
+ volatile __int128 s128 = u128;
+ fesetround (FE_UPWARD);
+ float fs = s128;
+ if (fs != -0x1.fffffep+126)
+ abort ();
+ double ds = s128;
+ if (ds != -0x1.fffffffffffffp+126)
+ abort ();
+#endif
+ exit (0);
+}
diff --git a/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-4.c b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-4.c
new file mode 100644
index 00000000000..e71610995cd
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-4.c
@@ -0,0 +1,27 @@
+/* Test for correct rounding of conversions from __int128 to
+ float. */
+/* { dg-do run } */
+/* { dg-require-effective-target int128 } */
+/* { dg-options "-frounding-math" } */
+
+#include <fenv.h>
+#include <stdlib.h>
+
+int
+main (void)
+{
+#ifdef FE_TOWARDZERO
+ volatile unsigned long long h = 0x8000000000000000LL;
+ volatile unsigned long long l = 0xdLL;
+ volatile unsigned __int128 u128 = (((unsigned __int128) h) << 64) | l;
+ volatile __int128 s128 = u128;
+ fesetround (FE_TOWARDZERO);
+ float fs = s128;
+ if (fs != -0x1.fffffep+126)
+ abort ();
+ double ds = s128;
+ if (ds != -0x1.fffffffffffffp+126)
+ abort ();
+#endif
+ exit (0);
+}
diff --git a/libgcc/libgcc2.c b/libgcc/libgcc2.c
index d84f25b0779..04d3185e805 100644
--- a/libgcc/libgcc2.c
+++ b/libgcc/libgcc2.c
@@ -1684,7 +1684,7 @@ FUNC (DWtype u)
/* No leading bits means u == minimum. */
if (count == 0)
- return -(Wtype_MAXp1_F * (Wtype_MAXp1_F / 2));
+ return Wtype_MAXp1_F * (FSTYPE) (hi | ((UWtype) u != 0));
shift = 1 + W_TYPE_SIZE - count;
--
2.20.1
