955e0f42fc
Add inline attr to CString::into_inner so it can optimize out NonNull checks It seems that currently if you convert any of the standard library's container to a pointer and then to a NonNull pointer, all will optimize out the NULL check except `CString`(https://godbolt.org/z/YPKW9G5xn), because for some reason `CString::into_inner` isn't inlined even though it's a private function that should compile into a simple `mov` instruction. Adding a simple `#[inline]` attribute solves this, code example: ```rust use std::ffi::CString; use std::ptr::NonNull; pub fn cstring_nonull(mut n: CString) -> NonNull<i8> { NonNull::new(CString::into_raw(n)).unwrap() } ``` assembly before: ```asm __ZN3wat14cstring_nonull17h371c755bcad76294E: .cfi_startproc pushq %rbp .cfi_def_cfa_offset 16 .cfi_offset %rbp, -16 movq %rsp, %rbp .cfi_def_cfa_register %rbp callq __ZN3std3ffi5c_str7CString10into_inner17h28ece07b276e2878E testq %rax, %rax je LBB0_2 popq %rbp retq LBB0_2: leaq l___unnamed_1(%rip), %rdi leaq l___unnamed_2(%rip), %rdx movl $43, %esi callq __ZN4core9panicking5panic17h92a83fa9085a8f73E .cfi_endproc .section __TEXT,__const l___unnamed_1: .ascii "called `Option::unwrap()` on a `None` value" l___unnamed_3: .ascii "wat.rs" .section __DATA,__const .p2align 3 l___unnamed_2: .quad l___unnamed_3 .asciz "\006\000\000\000\000\000\000\000\006\000\000\000(\000\000" ``` Assembly after: ```asm __ZN3wat14cstring_nonull17h9645eb9341fb25d7E: .cfi_startproc pushq %rbp .cfi_def_cfa_offset 16 .cfi_offset %rbp, -16 movq %rsp, %rbp .cfi_def_cfa_register %rbp movq %rdi, %rax popq %rbp retq .cfi_endproc ``` (Related discussion on zulip: https://rust-lang.zulipchat.com/#narrow/stream/219381-t-libs/topic/NonNull.20From.3CBox.3CT.3E.3E) |
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| .. | ||
| alloc | ||
| backtrace@221483ebaf | ||
| core | ||
| panic_abort | ||
| panic_unwind | ||
| proc_macro | ||
| profiler_builtins | ||
| rtstartup | ||
| rustc-std-workspace-alloc | ||
| rustc-std-workspace-core | ||
| rustc-std-workspace-std | ||
| std | ||
| stdarch@37d6e18863 | ||
| term | ||
| test | ||
| unwind | ||