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[PATCH 2/3] Add more tests for trunc.
- From: Matt Turner <mattst88 at gmail dot com>
- To: libc-alpha at sourceware dot org
- Cc: Joseph Myers <joseph at codesourcery dot com>, Matt Turner <mattst88 at gmail dot com>
- Date: Tue, 24 May 2016 18:32:29 -0700
- Subject: [PATCH 2/3] Add more tests for trunc.
- Authentication-results: sourceware.org; auth=none
- References: <1464139950-31943-1-git-send-email-mattst88 at gmail dot com>
Some implementations of truncf(x) add 2**23 to x with the rounding mode
set to truncate before subtracting 2**23 to produce the truncated
result. Unfortunately this doesn't work for odd values of x greater than
2**23, since the result of the addition is inexact and the parity bit is
lost by the rounding step. The same problems apply to implementations of
trunc on other floating-point data types.
2016-05-24 Matt Turner <mattst88@gmail.com>
* math/libm-test.inc (trunc_test_data): Add tests for odd
values.
---
math/libm-test.inc | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/math/libm-test.inc b/math/libm-test.inc
index f1ba7dd..84c119a 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -11413,18 +11413,23 @@ static const struct test_f_f_data trunc_test_data[] =
TEST_f_f (trunc, 1, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 2, 2, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p23, 0x1p23, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, 0x1p23 + 1, 0x1p23 + 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p24, 0x1p24, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p25, 0x1p25, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p52, 0x1p52, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, 0x1p52 + 1, 0x1p52 + 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p53, 0x1p53, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p54, 0x1p54, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p63, 0x1p63, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, 0x1p63 + 1, 0x1p63 + 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p64, 0x1p64, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p65, 0x1p65, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p105, 0x1p105, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, 0x1p105 + 1, 0x1p105 + 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p106, 0x1p106, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p107, 0x1p107, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p112, 0x1p112, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, 0x1p112 + 1, 0x1p112 + 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p113, 0x1p113, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, 0x1p114, 0x1p114, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, max_value, max_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
@@ -11433,18 +11438,23 @@ static const struct test_f_f_data trunc_test_data[] =
TEST_f_f (trunc, -1, -1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -2, -2, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p23, -0x1p23, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, -0x1p23 - 1, -0x1p23 - 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p24, -0x1p24, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p25, -0x1p25, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p52, -0x1p52, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, -0x1p52 - 1, -0x1p52 - 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p53, -0x1p53, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p54, -0x1p54, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p63, -0x1p63, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, -0x1p63 - 1, -0x1p63 - 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p64, -0x1p64, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p65, -0x1p65, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p105, -0x1p105, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, -0x1p105 - 1, -0x1p105 - 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p106, -0x1p106, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p107, -0x1p107, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p112, -0x1p112, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+ TEST_f_f (trunc, -0x1p112 - 1, -0x1p112 - 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p113, -0x1p113, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -0x1p114, -0x1p114, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_f (trunc, -max_value, -max_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
--
2.7.3