Search results

Redundant memset in convolution kernel

A-LLVMArea: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.Area: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

I-slowIssue: Problems and improvements with respect to performance of generated code.Issue: Problems and improvements with respect to performance of generated code.

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#142469 In rust-lang/rust;

· yugr opened on Jun 13, 2025

i32.clamp() suggested by Clippy produces worse code than i32.min().max()

A-LLVMArea: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.Area: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

I-slowIssue: Problems and improvements with respect to performance of generated code.Issue: Problems and improvements with respect to performance of generated code.

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#141915 In rust-lang/rust;

· Shnatsel opened on Jun 2, 2025

<code>char_indices</code> is slower than while loop over ascii <code>Chars</code>, but faster for unicode

A-UnicodeArea: UnicodeArea: Unicode

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#141855 In rust-lang/rust;

· hkBst opened on Jun 1, 2025

A moderate rustc/gcc performance difference

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

I-slowIssue: Problems and improvements with respect to performance of generated code.Issue: Problems and improvements with respect to performance of generated code.

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#141853 In rust-lang/rust;

· leonardo-m opened on Jun 1, 2025

rustc_session: be more precise about -Z plt=yes on x86-64?

A-codegenArea: Code generationArea: Code generation

A-linkageArea: linking into static, shared libraries and binariesArea: linking into static, shared libraries and binaries

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

I-slowIssue: Problems and improvements with respect to performance of generated code.Issue: Problems and improvements with respect to performance of generated code.

O-x86_64Target: x86-64 processors (like x86_64-*) (also known as amd64 and x64)Target: x86-64 processors (like x86_64-*) (also known as amd64 and x64)

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#141720 In rust-lang/rust;

· iximeow opened on May 29, 2025

Bounds check eliminated only when array length is a constant

A-LLVMArea: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.Area: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#141671 In rust-lang/rust;

· DaniPopes opened on May 28, 2025

Missed optimization: multiple instances of a small struct don't reuse the stack allocation

A-codegenArea: Code generationArea: Code generation

A-MIRArea: Mid-level IR (MIR) - https://blog.rust-lang.org/2016/04/19/MIR.htmlArea: Mid-level IR (MIR) - https://blog.rust-lang.org/2016/04/19/MIR.html

A-mir-optArea: MIR optimizationsArea: MIR optimizations

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

T-opsemRelevant to the opsem teamRelevant to the opsem team

Status: Open.

#141649 In rust-lang/rust;

· ohadravid opened on May 27, 2025

Missed optimization: <code>matches!</code> results in worse codgen than a logical or

A-LLVMArea: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.Area: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

I-slowIssue: Problems and improvements with respect to performance of generated code.Issue: Problems and improvements with respect to performance of generated code.

Status: Open.

#141497 In rust-lang/rust;

· ohadravid opened on May 24, 2025

Performance problem in for loops with step_by(run-time-variable)

A-iteratorsArea: IteratorsArea: Iterators

C-bugCategory: This is a bug.Category: This is a bug.

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

I-slowIssue: Problems and improvements with respect to performance of generated code.Issue: Problems and improvements with respect to performance of generated code.

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#141360 In rust-lang/rust;

· leonardo-m opened on May 21, 2025

Inlining leaves extra assembly

A-codegenArea: Code generationArea: Code generation

A-LLVMArea: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.Area: Code generation parts specific to LLVM. Both correctness bugs and optimization-related issues.

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

I-slowIssue: Problems and improvements with respect to performance of generated code.Issue: Problems and improvements with respect to performance of generated code.

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#141144 In rust-lang/rust;

· RoDmitry opened on May 17, 2025

removing needless <code>.collect()</code> in the middle of iterator chain reduces performance significantly

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

I-slowIssue: Problems and improvements with respect to performance of generated code.Issue: Problems and improvements with respect to performance of generated code.

S-needs-reproStatus: This issue has no reproduction and needs a reproduction to make progress.Status: This issue has no reproduction and needs a reproduction to make progress.

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#140873 In rust-lang/rust;

· cyrgani opened on May 9, 2025

Codegen Optimization for Non-Consecutive Enum Match Arms

C-optimizationCategory: An issue highlighting optimization opportunities or PRs implementing suchCategory: An issue highlighting optimization opportunities or PRs implementing such

T-compilerRelevant to the compiler team, which will review and decide on the PR/issue.Relevant to the compiler team, which will review and decide on the PR/issue.

Status: Open.

#140849 In rust-lang/rust;

· ray90514 opened on May 9, 2025