Module Name: src
Committed By: riastradh
Date: Sun Nov 5 16:06:27 UTC 2023
Modified Files:
src/tests/lib/libm: t_fenv.c
Log Message:
t_fenv: Verify rounding mode takes effect.
At least for addition operations, anyway.
Somewhat redundant with the test t_fe_round added by maya@ but this
gives two minimal pairs to easily diagnose exactly what the rounding
mode is when the wrong one was selected.
PR port-mips/57680
XXX pullup-10
To generate a diff of this commit:
cvs rdiff -u -r1.8 -r1.9 src/tests/lib/libm/t_fenv.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/tests/lib/libm/t_fenv.c
diff -u src/tests/lib/libm/t_fenv.c:1.8 src/tests/lib/libm/t_fenv.c:1.9
--- src/tests/lib/libm/t_fenv.c:1.8 Sun Nov 5 15:28:17 2023
+++ src/tests/lib/libm/t_fenv.c Sun Nov 5 16:06:27 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: t_fenv.c,v 1.8 2023/11/05 15:28:17 riastradh Exp $ */
+/* $NetBSD: t_fenv.c,v 1.9 2023/11/05 16:06:27 riastradh Exp $ */
/*-
* Copyright (c) 2014 The NetBSD Foundation, Inc.
@@ -29,7 +29,7 @@
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
-__RCSID("$NetBSD: t_fenv.c,v 1.8 2023/11/05 15:28:17 riastradh Exp $");
+__RCSID("$NetBSD: t_fenv.c,v 1.9 2023/11/05 16:06:27 riastradh Exp $");
#include <atf-c.h>
@@ -101,6 +101,45 @@ checkfltrounds(void)
FLT_ROUNDS, expected, feround);
}
+static void
+checkrounding(int feround)
+{
+ volatile double ulp1 = DBL_EPSILON;
+ double y1 = -1 + ulp1/4;
+ double y2 = 1 + 3*(ulp1/2);
+
+ switch (feround) {
+ case FE_TONEAREST: {
+ double z1 = -1;
+ double z2 = 1 + 2*ulp1;
+ ATF_CHECK_EQ_MSG(y1, z1, "expected=%a actual=%a", y1, z1);
+ ATF_CHECK_EQ_MSG(y2, z2, "expected=%a actual=%a", y1, z2);
+ break;
+ }
+ case FE_TOWARDZERO: {
+ double z1 = -1 + ulp1/2;
+ double z2 = 1 + ulp1;
+ ATF_CHECK_EQ_MSG(y1, z1, "expected=%a actual=%a", y1, z1);
+ ATF_CHECK_EQ_MSG(y2, z2, "expected=%a actual=%a", y1, z2);
+ break;
+ }
+ case FE_UPWARD: {
+ double z1 = -1 + ulp1/2;
+ double z2 = 1 + 2*ulp1;
+ ATF_CHECK_EQ_MSG(y1, z1, "expected=%a actual=%a", y1, z1);
+ ATF_CHECK_EQ_MSG(y2, z2, "expected=%a actual=%a", y1, z2);
+ break;
+ }
+ case FE_DOWNWARD: {
+ double z1 = -1;
+ double z2 = 1 + ulp1;
+ ATF_CHECK_EQ_MSG(y1, z1, "expected=%a actual=%a", y1, z1);
+ ATF_CHECK_EQ_MSG(y2, z2, "expected=%a actual=%a", y1, z2);
+ break;
+ }
+ }
+}
+
ATF_TC(fegetround);
ATF_TC_HEAD(fegetround, tc)
@@ -114,29 +153,35 @@ ATF_TC_BODY(fegetround, tc)
{
FPU_RND_PREREQ();
+ checkrounding(FE_TONEAREST);
+
fpsetround(FP_RZ);
ATF_CHECK_EQ_MSG(fegetround(), FE_TOWARDZERO,
"fegetround()=%d FE_TOWARDZERO=%d",
fegetround(), FE_TOWARDZERO);
checkfltrounds();
+ checkrounding(FE_TOWARDZERO);
fpsetround(FP_RM);
ATF_CHECK_EQ_MSG(fegetround(), FE_DOWNWARD,
"fegetround()=%d FE_DOWNWARD=%d",
fegetround(), FE_DOWNWARD);
checkfltrounds();
+ checkrounding(FE_DOWNWARD);
fpsetround(FP_RN);
ATF_CHECK_EQ_MSG(fegetround(), FE_TONEAREST,
"fegetround()=%d FE_TONEAREST=%d",
fegetround(), FE_TONEAREST);
checkfltrounds();
+ checkrounding(FE_TONEAREST);
fpsetround(FP_RP);
ATF_CHECK_EQ_MSG(fegetround(), FE_UPWARD,
"fegetround()=%d FE_UPWARD=%d",
fegetround(), FE_UPWARD);
checkfltrounds();
+ checkrounding(FE_UPWARD);
}
ATF_TC(fesetround);
@@ -152,29 +197,35 @@ ATF_TC_BODY(fesetround, tc)
{
FPU_RND_PREREQ();
+ checkrounding(FE_TONEAREST);
+
fesetround(FE_TOWARDZERO);
ATF_CHECK_EQ_MSG(fpgetround(), FP_RZ,
"fpgetround()=%d FP_RZ=%d",
(int)fpgetround(), (int)FP_RZ);
checkfltrounds();
+ checkrounding(FE_TOWARDZERO);
fesetround(FE_DOWNWARD);
ATF_CHECK_EQ_MSG(fpgetround(), FP_RM,
"fpgetround()=%d FP_RM=%d",
(int)fpgetround(), (int)FP_RM);
checkfltrounds();
+ checkrounding(FE_DOWNWARD);
fesetround(FE_TONEAREST);
ATF_CHECK_EQ_MSG(fpgetround(), FP_RN,
"fpgetround()=%d FP_RN=%d",
(int)fpgetround(), (int)FP_RN);
checkfltrounds();
+ checkrounding(FE_TONEAREST);
fesetround(FE_UPWARD);
ATF_CHECK_EQ_MSG(fpgetround(), FP_RP,
"fpgetround()=%d FP_RP=%d",
(int)fpgetround(), (int)FP_RP);
checkfltrounds();
+ checkrounding(FE_UPWARD);
}
ATF_TC(fegetexcept);
