From 130a1df71ea73ab9d66d3cb8fc9cdb43155d514b Mon Sep 17 00:00:00 2001 From: Augie Fackler Date: Mon, 21 Mar 2022 15:30:54 -0400 Subject: codegen: use new {re,de,}allocator annotations in llvm This obviates the patch that teaches LLVM internals about _rust_{re,de}alloc functions by putting annotations directly in the IR for the optimizer. The sole test change is required to anchor FileCheck to the body of the `box_uninitialized` method, so it doesn't see the `allocalign` on `__rust_alloc` and get mad about the string `alloca` showing up. Since I was there anyway, I added some checks on the attributes to prove the right attributes got set. While we're here, we also emit allocator attributes on __rust_alloc_zeroed. This should allow LLVM to perform more optimizations for zeroed blocks, and probably fixes #90032. [This comment](https://github.com/rust-lang/rust/issues/24194#issuecomment-308791157) mentions "weird UB-like behaviour with bitvec iterators in rustc_data_structures" so we may need to back this change out if things go wrong. The new test cases require LLVM 15, so we copy them into LLVM 14-supporting versions, which we can delete when we drop LLVM 14. --- compiler/rustc_feature/src/builtin_attrs.rs | 3 +++ 1 file changed, 3 insertions(+) (limited to 'compiler/rustc_feature/src') diff --git a/compiler/rustc_feature/src/builtin_attrs.rs b/compiler/rustc_feature/src/builtin_attrs.rs index c806df82145..7b540e67aab 100644 --- a/compiler/rustc_feature/src/builtin_attrs.rs +++ b/compiler/rustc_feature/src/builtin_attrs.rs @@ -532,6 +532,9 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[ rustc_attr!(rustc_allocator, Normal, template!(Word), WarnFollowing, IMPL_DETAIL), rustc_attr!(rustc_allocator_nounwind, Normal, template!(Word), WarnFollowing, IMPL_DETAIL), + rustc_attr!(rustc_reallocator, Normal, template!(Word), WarnFollowing, IMPL_DETAIL), + rustc_attr!(rustc_deallocator, Normal, template!(Word), WarnFollowing, IMPL_DETAIL), + rustc_attr!(rustc_allocator_zeroed, Normal, template!(Word), WarnFollowing, IMPL_DETAIL), gated!( alloc_error_handler, Normal, template!(Word), WarnFollowing, experimental!(alloc_error_handler) -- cgit 1.4.1-3-g733a5