StateTransform: Do not renumber resume local. #146552
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| Some changes occurred to MIR optimizations cc @rust-lang/wg-mir-opt |
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cjgillot force-pushed the resume-noremap branch from fb00c01 to 2dc12f6 Compare This comment has been minimized.
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cjgillot force-pushed the resume-noremap branch from 2dc12f6 to c1bda59 Compare | r? compiler |
| Seems reasonable to me. Curious if there was some particular reason this was written this way. @bors r+ |
bors added S-waiting-on-bors Zalathar added a commit to Zalathar/rust that referenced this pull request Sep 16, 2025
StateTransform: Do not renumber resume local. MIR parameters are not explicitly assigned-to when entering the MIR body. If we want to save their values inside the coroutine state, we need to do so explicitly. This was done by renaming the `_2` local, and introducing an explicit assignment pre-transform. This particular trick confuses me. This version makes explicit that we are assigning parameters to saved locals. r? `@dingxiangfei2009`
bors added a commit that referenced this pull request Sep 16, 2025
Rollup of 4 pull requests Successful merges: - #143613 (Fix backtraces with `-C panic=abort` on linux; emit unwind tables by default) - #145181 (remove FIXME block from `has_significant_drop`, it never encounters inference variables) - #146552 (StateTransform: Do not renumber resume local.) - #146588 (tests/run-make: Update list of statically linked musl targets) r? `@ghost` `@rustbot` modify labels: rollup
| Probably failed in rollup: #146625 (comment) @bors r- |
bors added S-waiting-on-author cjgillot force-pushed the resume-noremap branch from c1bda59 to eddd755 Compare | This PR was rebased onto a different master commit. Here's a range-diff highlighting what actually changed. Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers. |
| @bors r=jackh726 |
bors added S-waiting-on-bors Zalathar added a commit to Zalathar/rust that referenced this pull request Sep 17, 2025
StateTransform: Do not renumber resume local. MIR parameters are not explicitly assigned-to when entering the MIR body. If we want to save their values inside the coroutine state, we need to do so explicitly. This was done by renaming the `_2` local, and introducing an explicit assignment pre-transform. This particular trick confuses me. This version makes explicit that we are assigning parameters to saved locals. r? `@dingxiangfei2009`
This was referenced Sep 17, 2025
bors added a commit that referenced this pull request Sep 17, 2025
Rollup of 14 pull requests Successful merges: - #142807 (libtest: expose --fail-fast as an unstable command-line option) - #144871 (Stabilize `btree_entry_insert` feature) - #145071 (Update the minimum external LLVM to 20) - #145181 (remove FIXME block from `has_significant_drop`, it never encounters inference variables) - #145660 (initial implementation of the darwin_objc unstable feature) - #145838 (don't apply temporary lifetime extension rules to non-extended `super let`) - #146259 (Suggest removing Box::new instead of unboxing it) - #146410 (Iterator repeat: no infinite loop for `last` and `count`) - #146460 (Add tidy readme) - #146552 (StateTransform: Do not renumber resume local.) - #146564 (Remove Rvalue::Len again.) - #146581 (Detect attempt to use var-args in closure) - #146588 (tests/run-make: Update list of statically linked musl targets) - #146631 (cg_llvm: Replace some DIBuilder wrappers with LLVM-C API bindings (part 3)) r? `@ghost` `@rustbot` modify labels: rollup
rust-timer added a commit that referenced this pull request Sep 17, 2025
Rollup merge of #146552 - cjgillot:resume-noremap, r=jackh726 StateTransform: Do not renumber resume local. MIR parameters are not explicitly assigned-to when entering the MIR body. If we want to save their values inside the coroutine state, we need to do so explicitly. This was done by renaming the `_2` local, and introducing an explicit assignment pre-transform. This particular trick confuses me. This version makes explicit that we are assigning parameters to saved locals. r? ``@dingxiangfei2009``
github-actions bot pushed a commit to rust-lang/rustc-dev-guide that referenced this pull request Sep 22, 2025
Rollup of 14 pull requests Successful merges: - rust-lang/rust#142807 (libtest: expose --fail-fast as an unstable command-line option) - rust-lang/rust#144871 (Stabilize `btree_entry_insert` feature) - rust-lang/rust#145071 (Update the minimum external LLVM to 20) - rust-lang/rust#145181 (remove FIXME block from `has_significant_drop`, it never encounters inference variables) - rust-lang/rust#145660 (initial implementation of the darwin_objc unstable feature) - rust-lang/rust#145838 (don't apply temporary lifetime extension rules to non-extended `super let`) - rust-lang/rust#146259 (Suggest removing Box::new instead of unboxing it) - rust-lang/rust#146410 (Iterator repeat: no infinite loop for `last` and `count`) - rust-lang/rust#146460 (Add tidy readme) - rust-lang/rust#146552 (StateTransform: Do not renumber resume local.) - rust-lang/rust#146564 (Remove Rvalue::Len again.) - rust-lang/rust#146581 (Detect attempt to use var-args in closure) - rust-lang/rust#146588 (tests/run-make: Update list of statically linked musl targets) - rust-lang/rust#146631 (cg_llvm: Replace some DIBuilder wrappers with LLVM-C API bindings (part 3)) r? `@ghost` `@rustbot` modify labels: rollup
rust-cloud-vms bot pushed a commit to makai410/rustc_public that referenced this pull request Oct 12, 2025
Rollup of 14 pull requests Successful merges: - rust-lang/rust#142807 (libtest: expose --fail-fast as an unstable command-line option) - rust-lang/rust#144871 (Stabilize `btree_entry_insert` feature) - rust-lang/rust#145071 (Update the minimum external LLVM to 20) - rust-lang/rust#145181 (remove FIXME block from `has_significant_drop`, it never encounters inference variables) - rust-lang/rust#145660 (initial implementation of the darwin_objc unstable feature) - rust-lang/rust#145838 (don't apply temporary lifetime extension rules to non-extended `super let`) - rust-lang/rust#146259 (Suggest removing Box::new instead of unboxing it) - rust-lang/rust#146410 (Iterator repeat: no infinite loop for `last` and `count`) - rust-lang/rust#146460 (Add tidy readme) - rust-lang/rust#146552 (StateTransform: Do not renumber resume local.) - rust-lang/rust#146564 (Remove Rvalue::Len again.) - rust-lang/rust#146581 (Detect attempt to use var-args in closure) - rust-lang/rust#146588 (tests/run-make: Update list of statically linked musl targets) - rust-lang/rust#146631 (cg_llvm: Replace some DIBuilder wrappers with LLVM-C API bindings (part 3)) r? `@ghost` `@rustbot` modify labels: rollup
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MIR parameters are not explicitly assigned-to when entering the MIR body. If we want to save their values inside the coroutine state, we need to do so explicitly.
This was done by renaming the
_2local, and introducing an explicit assignment pre-transform. This particular trick confuses me.This version makes explicit that we are assigning parameters to saved locals.
r? @dingxiangfei2009