Skip to content

[libc][math][c++23] Add {get,set}payloadbf16 and setpayloadsigbf16 math functions #153994

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 17 commits into from
Aug 22, 2025
Merged

[libc][math][c++23] Add {get,set}payloadbf16 and setpayloadsigbf16 math functions #153994

Show file tree
Hide file tree
Changes from 13 commits
Commits
Show all changes
17 commits
Select commit Hold shift + click to select a range
b58785d
feat: implement {,u}fromfp{,x}bf16 math functions
krishna2803 Aug 16, 2025
0a2b527
chore: add tests for {,u}fromfp{,x}bf16 math functions
krishna2803 Aug 16, 2025
baaf0e0
chore: update entrypoints
krishna2803 Aug 16, 2025
733f4f1
chore: update docs
krishna2803 Aug 16, 2025
4a80312
feat: implement next{after,down,toward,up}bf16 math functions
krishna2803 Aug 17, 2025
446e637
chore: add smoke tests for next{after,down,toward,up}bf16 math functions
krishna2803 Aug 17, 2025
a98b928
chore: update entrypoints
krishna2803 Aug 17, 2025
12f1923
docs: add next{after,down,toward,up}bf16 math functions
krishna2803 Aug 17, 2025
6f8d84d
feat: implement {get,set}payloadbf16 and setpayloadsigbf16 math funct…
krishna2803 Aug 17, 2025
c8f4380
chore: implement smoke tests for {get,set}payloadbf16 and setpayloads…
krishna2803 Aug 17, 2025
8ea9354
fix: add correct static_cast for fputil::getpload for bfloat16
krishna2803 Aug 17, 2025
fc2b6eb
chore: update entrypoints
krishna2803 Aug 17, 2025
70e4463
docs: add {get,set}payloadbf16 and setpayloadsigbf16 math functions
krishna2803 Aug 17, 2025
5ad41c5
revert: "fix: add correct static_cast for fputil::getpload for bfloat16"
krishna2803 Aug 20, 2025
3486509
fix: remove BFloat16(uint16) ctor
krishna2803 Aug 20, 2025
c1f0b9e
Merge branch 'main' into users/krishna2803/payloadbf16
krishna2803 Aug 22, 2025
b310e15
nit: add separate gaurd for 5 bits
krishna2803 Aug 22, 2025
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
11 changes: 11 additions & 0 deletions libc/config/baremetal/aarch64/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -785,9 +785,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

if(LIBC_TYPES_HAS_FLOAT128)
Expand Down
11 changes: 11 additions & 0 deletions libc/config/baremetal/arm/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -788,9 +788,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

if(LIBC_TYPES_HAS_FLOAT128)
Expand Down
11 changes: 11 additions & 0 deletions libc/config/baremetal/riscv/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -788,9 +788,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

if(LIBC_TYPES_HAS_FLOAT128)
Expand Down
11 changes: 11 additions & 0 deletions libc/config/darwin/aarch64/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -618,9 +618,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

if(LIBC_TYPES_HAS_FLOAT128)
Expand Down
12 changes: 11 additions & 1 deletion libc/config/darwin/x86_64/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -261,10 +261,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16

libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

set(TARGET_LLVMLIBC_ENTRYPOINTS
Expand Down
11 changes: 11 additions & 0 deletions libc/config/gpu/amdgpu/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -644,9 +644,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

set(TARGET_LLVMLIBC_ENTRYPOINTS
Expand Down
11 changes: 11 additions & 0 deletions libc/config/gpu/nvptx/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -645,9 +645,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

set(TARGET_LLVMLIBC_ENTRYPOINTS
Expand Down
11 changes: 11 additions & 0 deletions libc/config/linux/aarch64/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -872,9 +872,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

if(LIBC_TYPES_HAS_FLOAT128)
Expand Down
11 changes: 11 additions & 0 deletions libc/config/linux/arm/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -488,9 +488,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

set(TARGET_LLVMLIBC_ENTRYPOINTS
Expand Down
11 changes: 11 additions & 0 deletions libc/config/linux/riscv/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -891,9 +891,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

if(LIBC_TYPES_HAS_FLOAT128)
Expand Down
11 changes: 11 additions & 0 deletions libc/config/linux/x86_64/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -923,9 +923,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

if(LIBC_TYPES_HAS_FLOAT128)
Expand Down
11 changes: 11 additions & 0 deletions libc/config/windows/entrypoints.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -334,9 +334,20 @@ list(APPEND TARGET_LIBM_ENTRYPOINTS
libc.src.math.fminimum_magbf16
libc.src.math.fminimum_mag_numbf16
libc.src.math.fminimum_numbf16
libc.src.math.fromfpbf16
libc.src.math.fromfpxbf16
libc.src.math.getpayloadbf16
libc.src.math.nextafterbf16
libc.src.math.nextdownbf16
libc.src.math.nexttowardbf16
libc.src.math.nextupbf16
libc.src.math.roundbf16
libc.src.math.roundevenbf16
libc.src.math.setpayloadbf16
libc.src.math.setpayloadsigbf16
libc.src.math.truncbf16
libc.src.math.ufromfpbf16
libc.src.math.ufromfpxbf16
)

set(TARGET_LLVMLIBC_ENTRYPOINTS
Expand Down
22 changes: 11 additions & 11 deletions libc/docs/headers/math/index.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -181,13 +181,13 @@ Basic Operations
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| frexp | |check| | |check| | |check| | |check| | |check| | | 7.12.6.7 | F.10.3.7 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| fromfp | |check| | |check| | |check| | |check| | |check| | | 7.12.9.10 | F.10.6.10 |
| fromfp | |check| | |check| | |check| | |check| | |check| | |check| | 7.12.9.10 | F.10.6.10 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| fromfpx | |check| | |check| | |check| | |check| | |check| | | 7.12.9.11 | F.10.6.11 |
| fromfpx | |check| | |check| | |check| | |check| | |check| | |check| | 7.12.9.11 | F.10.6.11 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| fsub | N/A | |check| | |check| | N/A | |check|\* | N/A | 7.12.14.2 | F.10.11 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| getpayload | |check| | |check| | |check| | |check| | |check| | | F.10.13.1 | N/A |
| getpayload | |check| | |check| | |check| | |check| | |check| | |check| | F.10.13.1 | N/A |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| ilogb | |check| | |check| | |check| | |check| | |check| | | 7.12.6.8 | F.10.3.8 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
Expand Down Expand Up @@ -215,13 +215,13 @@ Basic Operations
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| nearbyint | |check| | |check| | |check| | |check| | |check| | | 7.12.9.3 | F.10.6.3 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| nextafter | |check| | |check| | |check| | |check| | |check| | | 7.12.11.3 | F.10.8.3 |
| nextafter | |check| | |check| | |check| | |check| | |check| | |check| | 7.12.11.3 | F.10.8.3 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| nextdown | |check| | |check| | |check| | |check| | |check| | | 7.12.11.6 | F.10.8.6 |
| nextdown | |check| | |check| | |check| | |check| | |check| | |check| | 7.12.11.6 | F.10.8.6 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| nexttoward | |check| | |check| | |check| | |check| | N/A | | 7.12.11.4 | F.10.8.4 |
| nexttoward | |check| | |check| | |check| | |check| | N/A | |check| | 7.12.11.4 | F.10.8.4 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| nextup | |check| | |check| | |check| | |check| | |check| | | 7.12.11.5 | F.10.8.5 |
| nextup | |check| | |check| | |check| | |check| | |check| | |check| | 7.12.11.5 | F.10.8.5 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| remainder | |check| | |check| | |check| | |check| | |check| | | 7.12.10.2 | F.10.7.2 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
Expand All @@ -237,19 +237,19 @@ Basic Operations
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| scalbn | |check| | |check| | |check| | |check| | |check| | | 7.12.6.19 | F.10.3.19 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| setpayload | |check| | |check| | |check| | |check| | |check| | | F.10.13.2 | N/A |
| setpayload | |check| | |check| | |check| | |check| | |check| | |check| | F.10.13.2 | N/A |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| setpayloadsig | |check| | |check| | |check| | |check| | |check| | | F.10.13.3 | N/A |
| setpayloadsig | |check| | |check| | |check| | |check| | |check| | |check| | F.10.13.3 | N/A |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| totalorder | |check| | |check| | |check| | |check| | |check| | | F.10.12.1 | N/A |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| totalordermag | |check| | |check| | |check| | |check| | |check| | | F.10.12.2 | N/A |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| trunc | |check| | |check| | |check| | |check| | |check| | |check| | 7.12.9.9 | F.10.6.9 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| ufromfp | |check| | |check| | |check| | |check| | |check| | | 7.12.9.10 | F.10.6.10 |
| ufromfp | |check| | |check| | |check| | |check| | |check| | |check| | 7.12.9.10 | F.10.6.10 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+
| ufromfpx | |check| | |check| | |check| | |check| | |check| | | 7.12.9.11 | F.10.6.11 |
| ufromfpx | |check| | |check| | |check| | |check| | |check| | |check| | 7.12.9.11 | F.10.6.11 |
+------------------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+------------------------+----------------------------+

Higher Math Functions
Expand Down
5 changes: 4 additions & 1 deletion libc/src/__support/FPUtil/BasicOperations.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -354,7 +354,10 @@ LIBC_INLINE cpp::enable_if_t<cpp::is_floating_point_v<T>, T> getpayload(T x) {

return static_cast<T>(payload_dfloat);
} else {
return static_cast<T>(payload);
if constexpr (cpp::is_same_v<T, bfloat16>)
return T(static_cast<int>(payload));
else
return static_cast<T>(payload);
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Why do we have the BFloat16(uint16_t bits) constructor again? Removing it makes this change unnecessary and libc-math-smoke-tests and libc.test.src.__support.FPUtil.bfloat16_test.__unit__ still pass.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I added it in case we might need to construct bfloat16 directly using uint16 values to be able to set its bits directly, but I think it can be removed as we don't use it anywhere. I will run all tests locally to confirm this.

}
}

Expand Down
Loading
Loading