Use a C-safe return type for __rust_[ui]128_* overflowing intrinsics#735
Merged
tgross35 merged 1 commit intorust-lang:masterfrom Jan 15, 2025
Merged
Conversation
tgross35
added a commit
to tgross35/rust
that referenced
this pull request
Dec 15, 2024
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
bjorn3
reviewed
Dec 15, 2024
|
|
||
| pub extern "C" fn __rust_i128_addo(a: i128, b: i128) -> (i128, bool) { | ||
| a.addo(b) | ||
| pub extern "C" fn __rust_i128_addo(a: i128, b: i128, oflow: &mut i32) -> i128 { |
Member
There was a problem hiding this comment.
Would you mind keeping the existing functions for a bit and adding new functions with the new ABI? That way the cg_clif update and the compiler-builtins update don't have to be done at the exact same time.
Contributor
Author
There was a problem hiding this comment.
I can do so if it helps, but why would this be needed? We pin the version of compiler_builtins with = now so it shouldn't get out of sync, and I won't merge this until the r-l/rust PR gets approved.
Member
There was a problem hiding this comment.
We pin the version of compiler_builtins with = now so it shouldn't get out of sync, and I won't merge this until the r-l/rust PR gets approved.
In that case I guess it is fine to keep as-is.
tgross35
added a commit
to tgross35/rust
that referenced
this pull request
Dec 17, 2024
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
tgross35
added a commit
to tgross35/rust
that referenced
this pull request
Dec 17, 2024
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
bjorn3
reviewed
Jan 9, 2025
| pub extern "C" fn __rust_u128_subo(a: u128, b: u128, oflow: &mut i32) -> u128 { | ||
| let (sub, o) = a.subo(b); | ||
| *oflow = o.into(); | ||
| sub |
Member
There was a problem hiding this comment.
cg_clif doesn't actually use the add/sub intrinsics, so I opened #745 to remove them.
bjorn3
reviewed
Jan 9, 2025
Member
bjorn3
left a comment
bjorn3
left a comment
There was a problem hiding this comment.
Rustfmt doesn't work inside macros.
11 tasks
tgross35
added a commit
to tgross35/rust
that referenced
this pull request
Jan 9, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
tgross35
added a commit
to tgross35/rust
that referenced
this pull request
Jan 10, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
bjorn3
approved these changes
Jan 10, 2025
Contributor
Author
|
Thanks for the review. I won't merge this until bumping builtins is unblocked, and the rust-lang/rust PR is ready to go. |
rust-cloud-vms bot
pushed a commit
to tgross35/rust
that referenced
this pull request
Jan 11, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
rust-cloud-vms bot
pushed a commit
to tgross35/rust
that referenced
this pull request
Jan 11, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
rust-cloud-vms bot
pushed a commit
to tgross35/rust
that referenced
this pull request
Jan 11, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
rust-cloud-vms bot
pushed a commit
to tgross35/rust
that referenced
this pull request
Jan 12, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
Most of our Rust-specific overflowing intrinsics currently return `(i128, bool)`, which is not guaranteed to have a stable ABI. Switch to returning the overflow via a mutable parameter and only directly returning the integer result. `__rust_i128_mulo` now matches the function signature of `__muloti4`, but they do not share the same ABI on Windows so we cannot easily deduplicate them.
tgross35
force-pushed
the
overflowing-c-safe-ret
branch
from
ce68bb9 to
a52b550
Compare
tgross35
added a commit
to tgross35/rust
that referenced
this pull request
Jan 15, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
jhpratt
added a commit
to jhpratt/rust
that referenced
this pull request
Jan 15, 2025
…=bjorn3,antoyo Use a C-safe return type for `__rust_[ui]128_*` overflowing intrinsics Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
rust-timer
added a commit
to rust-lang-ci/rust
that referenced
this pull request
Jan 15, 2025
Rollup merge of rust-lang#134338 - tgross35:overflowing-c-safe-ret, r=bjorn3,antoyo Use a C-safe return type for `__rust_[ui]128_*` overflowing intrinsics Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
bjorn3
pushed a commit
to rust-lang/rustc_codegen_cranelift
that referenced
this pull request
Jan 16, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
antoyo
pushed a commit
to rust-lang/rustc_codegen_gcc
that referenced
this pull request
Jan 30, 2025
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
antoyo
pushed a commit
to rust-lang/rustc_codegen_gcc
that referenced
this pull request
Jan 30, 2025
…ntoyo Use a C-safe return type for `__rust_[ui]128_*` overflowing intrinsics Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
github-actions bot
pushed a commit
to tautschnig/verify-rust-std
that referenced
this pull request
Mar 11, 2025
…=bjorn3,antoyo Use a C-safe return type for `__rust_[ui]128_*` overflowing intrinsics Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
christian-schilling
pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
christian-schilling
pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
…ntoyo Use a C-safe return type for `__rust_[ui]128_*` overflowing intrinsics Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
christian-schilling
pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
christian-schilling
pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
…ntoyo Use a C-safe return type for `__rust_[ui]128_*` overflowing intrinsics Combined with [1], this will change the overflowing multiplication operations to return an `extern "C"`-safe type. Link: rust-lang/compiler-builtins#735 [1]
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Most of our Rust-specific overflowing intrinsics currently return
(i128, bool), which is not guaranteed to have a stable ABI. Switch to returning the overflow via a mutable parameter and only directly returning the integer result.__rust_i128_mulonow matches the function signature of__muloti4, but they do not share the same ABI on Windows so we cannot easily deduplicate them.