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authorChris Metcalf <cmetcalf@ezchip.com>2015-01-05 11:59:32 -0500
committerChris Metcalf <cmetcalf@ezchip.com>2015-01-05 11:59:32 -0500
commit1dca195e1c50d69fa4f0d18e821ec68f5d286df4 (patch)
treecccf48935689a483d2a815cd8d5d82f5718ce55c
parentab70da77ea8076b49ad81a8c06103c51d4e81dc4 (diff)
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lround: provide cast for wordsize-64 version if needed
Platforms with 64-bit registers where 32-bit values need to have the high 32 bits set in a particular way need to have an explicit cast when using the 64-bit sysdeps/ieee754/dbl-64/wordsize-64 version of llround() as lround(). This includes tilegx32, and likely MIPS. x32 does not need this, and AArch64 ILP32 will not either. Require it to be specified in sysdep.h to be explicit.
-rw-r--r--ChangeLog9
-rw-r--r--sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c28
-rw-r--r--sysdeps/tile/sysdep.h4
-rw-r--r--sysdeps/x86_64/x32/sysdep.h4
4 files changed, 39 insertions, 6 deletions
diff --git a/ChangeLog b/ChangeLog
index 0e6e224927..123b0b28fc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2015-01-05 Chris Metcalf <cmetcalf@ezchip.com>
+
+ * sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c [!defined _LP64
+ && REGISTER_CAST_INT32_TO_INT64]: Provide explicit lround()
+ function with cast from llround().
+ * sysdeps/tile/sysdep.h (REGISTER_CAST_INT32_TO_INT64): Define.
+ * sysdeps/x86_64/x32/sysdep.h (REGISTER_CAST_INT32_TO_INT64):
+ Define.
+
2015-01-05 Joseph Myers <joseph@codesourcery.com>
[BZ #17793]
diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c b/sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c
index 885260163e..8bb52524b7 100644
--- a/sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c
+++ b/sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c
@@ -21,6 +21,7 @@
#define __lround __hidden___lround
#include <math.h>
+#include <sysdep.h>
#include <math_private.h>
@@ -64,16 +65,31 @@ __llround (double x)
weak_alias (__llround, llround)
#ifdef NO_LONG_DOUBLE
-strong_alias (__llround, __lroundl)
-weak_alias (__llround, lroundl)
+strong_alias (__llround, __llroundl)
+weak_alias (__llround, llroundl)
#endif
-/* long has the same width as long long on 64-bit machines. */
+/* long has the same width as long long on LP64 machines, so use an alias.
+ If building for ILP32 on a machine with 64-bit registers, however,
+ use a cast if necessary. */
#undef lround
#undef __lround
+#if !defined (_LP64) && REGISTER_CAST_INT32_TO_INT64
+long int
+__lround (double x)
+{
+ return __llround (x);
+}
+weak_alias (__lround, lround)
+# ifdef NO_LONG_DOUBLE
+strong_alias (__lround, __lroundl)
+weak_alias (__lround, lroundl)
+# endif
+#else
strong_alias (__llround, __lround)
weak_alias (__llround, lround)
-#ifdef NO_LONG_DOUBLE
-strong_alias (__llround, __llroundl)
-weak_alias (__llround, llroundl)
+# ifdef NO_LONG_DOUBLE
+strong_alias (__llround, __lroundl)
+weak_alias (__llround, lroundl)
+# endif
#endif
diff --git a/sysdeps/tile/sysdep.h b/sysdeps/tile/sysdep.h
index ead9dba0b4..7b3d8739d2 100644
--- a/sysdeps/tile/sysdep.h
+++ b/sysdeps/tile/sysdep.h
@@ -108,3 +108,7 @@
#endif
#endif /* __ASSEMBLER__ */
+
+/* On tilegx, 32-bit values must have their high 32 bits sign extended;
+ random values are not allowed. */
+#define REGISTER_CAST_INT32_TO_INT64 1
diff --git a/sysdeps/x86_64/x32/sysdep.h b/sysdeps/x86_64/x32/sysdep.h
index 9b8700522f..0cbc1a083f 100644
--- a/sysdeps/x86_64/x32/sysdep.h
+++ b/sysdeps/x86_64/x32/sysdep.h
@@ -90,3 +90,7 @@
# define R15_LP "r15d"
#endif /* __ASSEMBLER__ */
+
+/* On x32, it is not required to normalize a 64-bit value before using
+ it as a 32-bit value. */
+#define REGISTER_CAST_INT32_TO_INT64 0