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 <[email protected]>
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 <[email protected]>
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 | 25 +++++++++++++++++++
.../gcc.dg/torture/fp-int-convert-timode-3.c | 25 +++++++++++++++++++
.../gcc.dg/torture/fp-int-convert-timode-4.c | 25 +++++++++++++++++++
libgcc/libgcc2.c | 2 +-
5 files changed, 101 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..8f831f7e98a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-2.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_DOWNWARD);
+ 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-3.c
b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-3.c
new file mode 100644
index 00000000000..12cac66f39d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-3.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_UPWARD);
+ float fs = s128;
+ if (fs != -0x1.fffffep+126)
+ abort ();
+ double ds = s128;
+ if (ds != -0x1.fffffffffffffp+126)
+ abort ();
+ 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..b1d8b83eb50
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/fp-int-convert-timode-4.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_TOWARDZERO);
+ float fs = s128;
+ if (fs != -0x1.fffffep+126)
+ abort ();
+ double ds = s128;
+ if (ds != -0x1.fffffffffffffp+126)
+ abort ();
+ 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
