Make FLT_ROUNDS correctly reflect the dynamic rounding mode.

6 files changed, 80 insertions, 3 deletions

diff --git a/lib/libc/amd64/gen/Makefile.inc b/lib/libc/amd64/gen/Makefile.inc
index 9f559e6..9cae7fa 100644
--- a/lib/libc/amd64/gen/Makefile.inc
+++ b/lib/libc/amd64/gen/Makefile.inc
@@ -4,5 +4,5 @@
 SRCS+=	_setjmp.S rfork_thread.S setjmp.S sigsetjmp.S \
 	fabs.S modf.S \
 	infinity.c ldexp.c makecontext.c signalcontext.c \
-	fpgetmask.c fpsetmask.c fpgetprec.c fpsetprec.c \
+	flt_rounds.c fpgetmask.c fpsetmask.c fpgetprec.c fpsetprec.c \
 	fpgetround.c fpsetround.c fpgetsticky.c fpsetsticky.c
diff --git a/lib/libc/amd64/gen/flt_rounds.c b/lib/libc/amd64/gen/flt_rounds.c
new file mode 100644
index 0000000..c0ce81f
--- /dev/null
+++ b/lib/libc/amd64/gen/flt_rounds.c
@@ -0,0 +1,26 @@
+/*
+ * Written by J.T. Conklin, Apr 10, 1995
+ * Public domain.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <float.h>
+
+static const int map[] = {
+	1,	/* round to nearest */
+	3,	/* round to zero */
+	2,	/* round to negative infinity */
+	0	/* round to positive infinity */
+};
+
+int
+__flt_rounds(void)
+{
+	int x;
+
+        /* Assume that the x87 and the SSE unit agree on the rounding mode. */
+	__asm("fnstcw %0" : "=m" (x));
+        return (map[(x >> 10) & 0x03]);
+}
diff --git a/lib/libc/i386/gen/Makefile.inc b/lib/libc/i386/gen/Makefile.inc
index fcfc9ec..7776387 100644
--- a/lib/libc/i386/gen/Makefile.inc
+++ b/lib/libc/i386/gen/Makefile.inc
@@ -2,5 +2,5 @@
 # $FreeBSD$
 
 SRCS+=	_ctx_start.S _setjmp.S alloca.S fabs.S \
-	infinity.c ldexp.c makecontext.c modf.S \
+	flt_rounds.c infinity.c ldexp.c makecontext.c modf.S \
 	rfork_thread.S setjmp.S signalcontext.c sigsetjmp.S
diff --git a/lib/libc/i386/gen/flt_rounds.c b/lib/libc/i386/gen/flt_rounds.c
new file mode 100644
index 0000000..16417ff
--- /dev/null
+++ b/lib/libc/i386/gen/flt_rounds.c
@@ -0,0 +1,25 @@
+/*
+ * Written by J.T. Conklin, Apr 10, 1995
+ * Public domain.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <float.h>
+
+static const int map[] = {
+	1,	/* round to nearest */
+	3,	/* round to zero */
+	2,	/* round to negative infinity */
+	0	/* round to positive infinity */
+};
+
+int
+__flt_rounds(void)
+{
+	int x;
+
+	__asm("fnstcw %0" : "=m" (x));
+        return (map[(x >> 10) & 0x03]);
+}
diff --git a/lib/libc/ia64/gen/Makefile.inc b/lib/libc/ia64/gen/Makefile.inc
index 30bb45e..f7dcd6a 100644
--- a/lib/libc/ia64/gen/Makefile.inc
+++ b/lib/libc/ia64/gen/Makefile.inc
@@ -2,7 +2,8 @@
 
 SRCS+=	__divdf3.S __divdi3.S __divsf3.S __divsi3.S __moddi3.S __modsi3.S \
 	__udivdi3.S __udivsi3.S __umoddi3.S __umodsi3.S _setjmp.S fabs.S \
-	fpgetmask.c fpgetround.c fpsetmask.c fpsetround.c infinity.c \
+	flt_rounds.c fpgetmask.c fpgetround.c fpsetmask.c \
+	fpsetround.c infinity.c \
 	ldexp.c makecontext.c modf.c setjmp.S signalcontext.c sigsetjmp.S
 
 # The following may go away if function _Unwind_FindTableEntry()
diff --git a/lib/libc/ia64/gen/flt_rounds.c b/lib/libc/ia64/gen/flt_rounds.c
new file mode 100644
index 0000000..d650965
--- /dev/null
+++ b/lib/libc/ia64/gen/flt_rounds.c
@@ -0,0 +1,25 @@
+/*
+ * Written by J.T. Conklin, Apr 10, 1995
+ * Public domain.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <float.h>
+
+static const int map[] = {
+	1,	/* round to nearest */
+	3,	/* round to zero */
+	2,	/* round to negative infinity */
+	0	/* round to positive infinity */
+};
+
+int
+__flt_rounds(void)
+{
+	int x;
+
+	__asm("mov %0=ar.fpsr" : "=r" (x));
+        return (map[(x >> 10) & 0x03]);
+}