Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

BUG: make a variable volatile to work around clang compiler bug #18030

Merged
merged 3 commits into from Dec 19, 2020
Merged

BUG: make a variable volatile to work around clang compiler bug #18030

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
fe20d87
BUG: make a variable volatile to work around clang compiler bug
r-devulap Dec 19, 2020
69343e8
Adding comments for relevance
r-devulap Dec 19, 2020
0ccc433
TST: Adding test to check for no overflow warnings in log
r-devulap Dec 19, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
12 changes: 10 additions & 2 deletions numpy/core/src/umath/simd.inc.src
View file
Open in desktop
Expand Up @@ -1549,7 +1549,11 @@ fma_get_exponent(__m256 x)
__m256 denormal_mask = _mm256_cmp_ps(x, _mm256_set1_ps(FLT_MIN), _CMP_LT_OQ);
__m256 normal_mask = _mm256_cmp_ps(x, _mm256_set1_ps(FLT_MIN), _CMP_GE_OQ);

__m256 temp1 = _mm256_blendv_ps(x, _mm256_set1_ps(0.0f), normal_mask);
/*
* It is necessary for temp1 to be volatile, a bug in clang optimizes it out which leads
* to an overflow warning in some cases. See https://github.com/numpy/numpy/issues/18005
*/
volatile __m256 temp1 = _mm256_blendv_ps(x, _mm256_set1_ps(0.0f), normal_mask);
__m256 temp = _mm256_mul_ps(temp1, two_power_100);
x = _mm256_blendv_ps(x, temp, denormal_mask);

Expand All @@ -1576,7 +1580,11 @@ fma_get_mantissa(__m256 x)
__m256 denormal_mask = _mm256_cmp_ps(x, _mm256_set1_ps(FLT_MIN), _CMP_LT_OQ);
__m256 normal_mask = _mm256_cmp_ps(x, _mm256_set1_ps(FLT_MIN), _CMP_GE_OQ);

__m256 temp1 = _mm256_blendv_ps(x, _mm256_set1_ps(0.0f), normal_mask);
/*
* It is necessary for temp1 to be volatile, a bug in clang optimizes it out which leads
* to an overflow warning in some cases. See https://github.com/numpy/numpy/issues/18005
*/
volatile __m256 temp1 = _mm256_blendv_ps(x, _mm256_set1_ps(0.0f), normal_mask);
__m256 temp = _mm256_mul_ps(temp1, two_power_100);
x = _mm256_blendv_ps(x, temp, denormal_mask);

Expand Down
5 changes: 5 additions & 0 deletions numpy/core/tests/test_umath.py
View file
Open in desktop
Expand Up @@ -727,6 +727,11 @@ def test_log_values(self):
assert_raises(FloatingPointError, np.log, np.float32(-np.inf))
assert_raises(FloatingPointError, np.log, np.float32(-1.0))

# See https://github.com/numpy/numpy/issues/18005
with assert_no_warnings():
a = np.array(1e9, dtype='float32')
np.log(a)

def test_sincos_values(self):
with np.errstate(all='ignore'):
x = [np.nan, np.nan, np.nan, np.nan]
Expand Down