Skip to content

Support ctr and lr as clobber-only registers in PowerPC inline assembly #146831

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
Merged
merged 1 commit into from
Sep 22, 2025
Merged

Support ctr and lr as clobber-only registers in PowerPC inline assembly #146831

merged 1 commit into from
Sep 22, 2025

Conversation

taiki-e
Copy link
Member

@taiki-e taiki-e commented Sep 21, 2025 •
edited by rustbot
Loading

Follow-up to #131341.

CTR and LR are marked as volatile in all ABIs, but I skipped them in #131341 due to they are currently marked as reserved.

rust/compiler/rustc_target/src/asm/powerpc.rs

Lines 209 to 212 in dd7fda5

#error = ["lr"] =>
"the link register cannot be used as an operand for inline asm",
#error = ["ctr"] =>
"the counter register cannot be used as an operand for inline asm",

However, they are actually only unusable as input/output of inline assembly, and should be fine to support as clobber-only registers as discussed in #t-compiler > ppc/ppc64 inline asm support.

r? @Amanieu or @workingjubilee

cc @programmerjake

@rustbot label +O-PowerPC +A-inline-assembly

@rustbot
Copy link
Collaborator

rustbot commented Sep 21, 2025

Some changes occurred in compiler/rustc_codegen_gcc

cc @antoyo, @GuillaumeGomez

@rustbot rustbot added A-LLVM Area: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues. S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Sep 21, 2025
@rustbot rustbot added A-inline-assembly Area: Inline assembly (`asm!(…)`) O-PowerPC Target: PowerPC processors labels Sep 21, 2025
@taiki-e taiki-e mentioned this pull request Sep 21, 2025
Open
11 tasks
@taiki-e
Copy link
Member Author

taiki-e commented Sep 21, 2025

cc @pmur

@taiki-e taiki-e mentioned this pull request Sep 21, 2025
Open
@Amanieu
Copy link
Member

Amanieu commented Sep 22, 2025

@bors r+

@bors
Copy link
Collaborator

bors commented Sep 22, 2025

📌 Commit f4b8768 has been approved by Amanieu

It is now in the queue for this repository.

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Sep 22, 2025
Zalathar added a commit to Zalathar/rust that referenced this pull request Sep 22, 2025
@Zalathar
Rollup merge of rust-lang#146831 - taiki-e:powerpc-clobber, r=Amanieu
ee3a7ee 
Support ctr and lr as clobber-only registers in PowerPC inline assembly

Follow-up to rust-lang#131341.

CTR and LR are marked as volatile in all ABIs, but I skipped them in rust-lang#131341 due to they are currently marked as reserved.
https://github.com/rust-lang/rust/blob/dd7fda570040e8a736f7d8bc28ddd1b444aabc82/compiler/rustc_target/src/asm/powerpc.rs#L209-L212

However, they are actually only unusable as input/output of inline assembly, and should be fine to support as clobber-only registers as discussed in [#t-compiler > ppc/ppc64 inline asm support](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/ppc.2Fppc64.20inline.20asm.20support/with/540413845).

r? `@Amanieu` or `@workingjubilee`

cc `@programmerjake`

`@rustbot` label +O-PowerPC +A-inline-assembly
@Zalathar Zalathar mentioned this pull request Sep 22, 2025
Closed
bors added a commit that referenced this pull request Sep 22, 2025
@bors
Auto merge of #146871 - Zalathar:rollup-e2pedcw, r=Zalathar
ce32c9b 
Rollup of 8 pull requests

Successful merges:

 - #146317 (Add panic=immediate-abort)
 - #146397 (std_detect on Darwin AArch64: update features)
 - #146594 (bootstrap: Don't force -static for musl targets in cc-rs)
 - #146791 (emit attribute for readonly non-pure inline assembly)
 - #146831 (Support ctr and lr as clobber-only registers in PowerPC inline assembly)
 - #146838 (Introduce "wrapper" helpers to rustdoc)
 - #146846 (btree InternalNode::new safety comments)
 - #146858 (Make mips64el-unknown-linux-muslabi64 link dynamically)

r? `@ghost`
`@rustbot` modify labels: rollup
Zalathar added a commit to Zalathar/rust that referenced this pull request Sep 22, 2025
@Zalathar
Rollup merge of rust-lang#146831 - taiki-e:powerpc-clobber, r=Amanieu
feede06 
Support ctr and lr as clobber-only registers in PowerPC inline assembly

Follow-up to rust-lang#131341.

CTR and LR are marked as volatile in all ABIs, but I skipped them in rust-lang#131341 due to they are currently marked as reserved.
https://github.com/rust-lang/rust/blob/dd7fda570040e8a736f7d8bc28ddd1b444aabc82/compiler/rustc_target/src/asm/powerpc.rs#L209-L212

However, they are actually only unusable as input/output of inline assembly, and should be fine to support as clobber-only registers as discussed in [#t-compiler > ppc/ppc64 inline asm support](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/ppc.2Fppc64.20inline.20asm.20support/with/540413845).

r? ``@Amanieu`` or ``@workingjubilee``

cc ``@programmerjake``

``@rustbot`` label +O-PowerPC +A-inline-assembly
@Zalathar Zalathar mentioned this pull request Sep 22, 2025
Closed
bors added a commit that referenced this pull request Sep 22, 2025
@bors
Auto merge of #146873 - Zalathar:rollup-u87iupw, r=Zalathar
702aba1 
Rollup of 10 pull requests

Successful merges:

 - #145411 (regression test for Cow<[u8]> layout)
 - #146317 (Add panic=immediate-abort)
 - #146397 (std_detect on Darwin AArch64: update features)
 - #146594 (bootstrap: Don't force -static for musl targets in cc-rs)
 - #146652 (Port `feature` to the new attribute system)
 - #146791 (emit attribute for readonly non-pure inline assembly)
 - #146831 (Support ctr and lr as clobber-only registers in PowerPC inline assembly)
 - #146838 (Introduce "wrapper" helpers to rustdoc)
 - #146846 (btree InternalNode::new safety comments)
 - #146858 (Make mips64el-unknown-linux-muslabi64 link dynamically)

r? `@ghost`
`@rustbot` modify labels: rollup
Zalathar added a commit to Zalathar/rust that referenced this pull request Sep 22, 2025
@Zalathar
Rollup merge of rust-lang#146831 - taiki-e:powerpc-clobber, r=Amanieu
67929be 
Support ctr and lr as clobber-only registers in PowerPC inline assembly

Follow-up to rust-lang#131341.

CTR and LR are marked as volatile in all ABIs, but I skipped them in rust-lang#131341 due to they are currently marked as reserved.
https://github.com/rust-lang/rust/blob/dd7fda570040e8a736f7d8bc28ddd1b444aabc82/compiler/rustc_target/src/asm/powerpc.rs#L209-L212

However, they are actually only unusable as input/output of inline assembly, and should be fine to support as clobber-only registers as discussed in [#t-compiler > ppc/ppc64 inline asm support](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/ppc.2Fppc64.20inline.20asm.20support/with/540413845).

r? ```@Amanieu``` or ```@workingjubilee```

cc ```@programmerjake```

```@rustbot``` label +O-PowerPC +A-inline-assembly
@Zalathar Zalathar mentioned this pull request Sep 22, 2025
Closed
bors added a commit that referenced this pull request Sep 22, 2025
@bors
Auto merge of #146876 - Zalathar:rollup-hfvkrpi, r=Zalathar
d3da100 
Rollup of 9 pull requests

Successful merges:

 - #145411 (regression test for Cow<[u8]> layout)
 - #146317 (Add panic=immediate-abort)
 - #146397 (std_detect on Darwin AArch64: update features)
 - #146594 (bootstrap: Don't force -static for musl targets in cc-rs)
 - #146791 (emit attribute for readonly non-pure inline assembly)
 - #146831 (Support ctr and lr as clobber-only registers in PowerPC inline assembly)
 - #146838 (Introduce "wrapper" helpers to rustdoc)
 - #146846 (btree InternalNode::new safety comments)
 - #146858 (Make mips64el-unknown-linux-muslabi64 link dynamically)

r? `@ghost`
`@rustbot` modify labels: rollup
bors added a commit that referenced this pull request Sep 22, 2025
@bors
Auto merge of #146876 - Zalathar:rollup-hfvkrpi, r=Zalathar
ac11cdb 
Rollup of 9 pull requests

Successful merges:

 - #145411 (regression test for Cow<[u8]> layout)
 - #146317 (Add panic=immediate-abort)
 - #146397 (std_detect on Darwin AArch64: update features)
 - #146594 (bootstrap: Don't force -static for musl targets in cc-rs)
 - #146791 (emit attribute for readonly non-pure inline assembly)
 - #146831 (Support ctr and lr as clobber-only registers in PowerPC inline assembly)
 - #146838 (Introduce "wrapper" helpers to rustdoc)
 - #146846 (btree InternalNode::new safety comments)
 - #146858 (Make mips64el-unknown-linux-muslabi64 link dynamically)

r? `@ghost`
`@rustbot` modify labels: rollup
@Zalathar Zalathar mentioned this pull request Sep 22, 2025
Merged
bors added a commit that referenced this pull request Sep 22, 2025
@bors
Auto merge of #146879 - Zalathar:rollup-vm97j8b, r=Zalathar
29005cb 
Rollup of 9 pull requests

Successful merges:

 - #145411 (regression test for Cow<[u8]> layout)
 - #146397 (std_detect on Darwin AArch64: update features)
 - #146791 (emit attribute for readonly non-pure inline assembly)
 - #146831 (Support ctr and lr as clobber-only registers in PowerPC inline assembly)
 - #146838 (Introduce "wrapper" helpers to rustdoc)
 - #146845 (Add self-profile events for target-machine creation)
 - #146846 (btree InternalNode::new safety comments)
 - #146858 (Make mips64el-unknown-linux-muslabi64 link dynamically)
 - #146878 (assert_unsafe_precondition: fix some incorrect check_language_ub)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 46be365 into rust-lang:master Sep 22, 2025
10 checks passed
@rustbot rustbot added this to the 1.92.0 milestone Sep 22, 2025
rust-timer added a commit that referenced this pull request Sep 22, 2025
@rust-timer
Unrolled build for #146831
82b1240 
Rollup merge of #146831 - taiki-e:powerpc-clobber, r=Amanieu

Support ctr and lr as clobber-only registers in PowerPC inline assembly

Follow-up to #131341.

CTR and LR are marked as volatile in all ABIs, but I skipped them in #131341 due to they are currently marked as reserved.
https://github.com/rust-lang/rust/blob/dd7fda570040e8a736f7d8bc28ddd1b444aabc82/compiler/rustc_target/src/asm/powerpc.rs#L209-L212

However, they are actually only unusable as input/output of inline assembly, and should be fine to support as clobber-only registers as discussed in [#t-compiler > ppc/ppc64 inline asm support](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/ppc.2Fppc64.20inline.20asm.20support/with/540413845).

r? ````@Amanieu```` or ````@workingjubilee````

cc ````@programmerjake````

````@rustbot```` label +O-PowerPC +A-inline-assembly
@taiki-e taiki-e deleted the powerpc-clobber branch September 22, 2025 14:38
Muscraft pushed a commit to Muscraft/rust that referenced this pull request Sep 24, 2025
@Zalathar @Muscraft
Rollup merge of rust-lang#146831 - taiki-e:powerpc-clobber, r=Amanieu
52d4d73 
Support ctr and lr as clobber-only registers in PowerPC inline assembly

Follow-up to rust-lang#131341.

CTR and LR are marked as volatile in all ABIs, but I skipped them in rust-lang#131341 due to they are currently marked as reserved.
https://github.com/rust-lang/rust/blob/dd7fda570040e8a736f7d8bc28ddd1b444aabc82/compiler/rustc_target/src/asm/powerpc.rs#L209-L212

However, they are actually only unusable as input/output of inline assembly, and should be fine to support as clobber-only registers as discussed in [#t-compiler > ppc/ppc64 inline asm support](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/ppc.2Fppc64.20inline.20asm.20support/with/540413845).

r? ````@Amanieu```` or ````@workingjubilee````

cc ````@programmerjake````

````@rustbot```` label +O-PowerPC +A-inline-assembly
Muscraft pushed a commit to Muscraft/rust that referenced this pull request Sep 24, 2025
@bors @Muscraft
Auto merge of rust-lang#146879 - Zalathar:rollup-vm97j8b, r=Zalathar
d68687c 
Rollup of 9 pull requests

Successful merges:

 - rust-lang#145411 (regression test for Cow<[u8]> layout)
 - rust-lang#146397 (std_detect on Darwin AArch64: update features)
 - rust-lang#146791 (emit attribute for readonly non-pure inline assembly)
 - rust-lang#146831 (Support ctr and lr as clobber-only registers in PowerPC inline assembly)
 - rust-lang#146838 (Introduce "wrapper" helpers to rustdoc)
 - rust-lang#146845 (Add self-profile events for target-machine creation)
 - rust-lang#146846 (btree InternalNode::new safety comments)
 - rust-lang#146858 (Make mips64el-unknown-linux-muslabi64 link dynamically)
 - rust-lang#146878 (assert_unsafe_precondition: fix some incorrect check_language_ub)

r? `@ghost`
`@rustbot` modify labels: rollup
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers
No reviews
Assignees

@Amanieu Amanieu

Labels
A-inline-assembly Area: Inline assembly (`asm!(…)`) A-LLVM Area: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues. O-PowerPC Target: PowerPC processors S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue.
Projects
None yet
Milestone
1.92.0
Development

Successfully merging this pull request may close these issues.
4 participants
@taiki-e @rustbot @Amanieu @bors