Skip to content

[SYCL][ESIMD] Fix an issue with tanh function implementation #7265

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

Merged
merged 3 commits into from
Nov 8, 2022
Merged

[SYCL][ESIMD] Fix an issue with tanh function implementation #7265

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
c2d7b25
Fix an issue with tanh function implementation
fineg74 Nov 2, 2022
4f60319
Update the range to avoid returning nan
fineg74 Nov 3, 2022
cff225e
Update calculation limit
fineg74 Nov 6, 2022
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 3 additions & 5 deletions sycl/include/sycl/ext/intel/experimental/esimd/math.hpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1574,7 +1574,6 @@ tanh_cody_waite_impl(__ESIMD_NS::simd<float, N> x) {
constexpr float xsmall = 4.22863966691620432990E-04f;
constexpr float xmedium = 0.54930614433405484570f;
constexpr float xlarge = 8.66433975699931636772f;
constexpr float log2E = 1.442695f; // same as esimd::log(e)

using RT = __ESIMD_NS::simd<float, N>;

Expand All @@ -1591,7 +1590,7 @@ tanh_cody_waite_impl(__ESIMD_NS::simd<float, N> x) {

RT res;
res.merge(sign, x, isLarge);
auto temp = __ESIMD_NS::exp(absX * 2.0f * log2E) + 1.f;
auto temp = __ESIMD_NS::exp(absX * 2.0f) + 1.f;
temp = ((temp - 2.f) / temp) * sign;
res.merge(temp, isGtMed);
res.merge((absX + absX * g * (g * p1 + p0) / (g + q0)) * sign, isGtSmall);
Expand All @@ -1609,8 +1608,7 @@ tanh_impl(__ESIMD_NS::simd<float, N> x) {
*/

constexpr float xsmall = 0.000045f; // same as exp(-10.0f)
constexpr float xlarge = 88.f;
constexpr float log2E = 1.442695f; // same as esimd::log(e)
constexpr float xlarge = 40.f;

using RT = __ESIMD_NS::simd<float, N>;

Expand All @@ -1626,7 +1624,7 @@ tanh_impl(__ESIMD_NS::simd<float, N> x) {
res.merge(sign, x, isLarge);

RT exp;
exp = __ESIMD_NS::exp(absX * 2.f * log2E);
exp = __ESIMD_NS::exp(absX * 2.f);

res.merge(((exp - 1.f) / (exp + 1.f)) * sign, (absX > xsmall) & isLessE);

Expand Down