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| author | bors <bors@rust-lang.org> | 2014-07-25 12:11:08 +0000 |
|---|---|---|
| committer | bors <bors@rust-lang.org> | 2014-07-25 12:11:08 +0000 |
| commit | 44019c79e0c7bd08d6136cd609eef619c97f45eb (patch) | |
| tree | 43738aed804df0d602ae3cadaeca30e36619ad1f | |
| parent | 470dbef29a3df65b6b7a7c7c46a28696eda1d031 (diff) | |
| parent | 4c2d4cd3dea344e81e4df24382ac3f23e2f86f40 (diff) | |
| download | rust-44019c79e0c7bd08d6136cd609eef619c97f45eb.tar.gz rust-44019c79e0c7bd08d6136cd609eef619c97f45eb.zip | |
auto merge of #15970 : Zoxc/rust/noalias-ref, r=cmr
This add the LLVM noalias attribute to parameters of a shared reference type (&) which have a safe interior.
| -rw-r--r-- | src/librustc/middle/trans/base.rs | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/src/librustc/middle/trans/base.rs b/src/librustc/middle/trans/base.rs index 68d8ab3f04c..fcdcb7847cb 100644 --- a/src/librustc/middle/trans/base.rs +++ b/src/librustc/middle/trans/base.rs @@ -2140,7 +2140,10 @@ pub fn get_fn_llvm_attributes(ccx: &CrateContext, fn_ty: ty::t) attrs.push((idx, llvm::NonNullAttribute as u64)); } // `&mut` pointer parameters never alias other parameters, or mutable global data - ty::ty_rptr(b, mt) if mt.mutbl == ast::MutMutable => { + // `&` pointer parameters never alias either (for LLVM's purposes) as long as the + // interior is safe + ty::ty_rptr(b, mt) if mt.mutbl == ast::MutMutable || + !ty::type_contents(ccx.tcx(), mt.ty).interior_unsafe() => { attrs.push((idx, llvm::NoAliasAttribute as u64)); attrs.push((idx, llvm::NonNullAttribute as u64)); match b { |