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Correct alignment of atomic types and (re)add Atomic{I,U}128

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LLVM requires that atomic loads and stores be aligned to at least the size of the type.
This commit is contained in:
Oliver Middleton
2018-09-08 12:50:19 +01:00
committed by Simonas Kazlauskas
parent 10f42cbde0
commit 01674fbe06
8 changed files with 169 additions and 20 deletions
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15
src/librustc_codegen_llvm/builder.rs
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@@ -482,14 +482,12 @@ impl Builder<'a, 'll, 'tcx> {
}
}
pub fn atomic_load(&self, ptr: &'ll Value, order: AtomicOrdering, align: Align) -> &'ll Value {
pub fn atomic_load(&self, ptr: &'ll Value, order: AtomicOrdering, size: Size) -> &'ll Value {
self.count_insn("load.atomic");
unsafe {
let load = llvm::LLVMRustBuildAtomicLoad(self.llbuilder, ptr, noname(), order);
// FIXME(eddyb) Isn't it UB to use `pref` instead of `abi` here?
// However, 64-bit atomic loads on `i686-apple-darwin` appear to
// require `___atomic_load` with ABI-alignment, so it's staying.
llvm::LLVMSetAlignment(load, align.pref() as c_uint);
// LLVM requires the alignment of atomic loads to be at least the size of the type.
llvm::LLVMSetAlignment(load, size.bytes() as c_uint);
load
}
}
@@ -564,15 +562,14 @@ impl Builder<'a, 'll, 'tcx> {
}
pub fn atomic_store(&self, val: &'ll Value, ptr: &'ll Value,
order: AtomicOrdering, align: Align) {
order: AtomicOrdering, size: Size) {
debug!("Store {:?} -> {:?}", val, ptr);
self.count_insn("store.atomic");
let ptr = self.check_store(val, ptr);
unsafe {
let store = llvm::LLVMRustBuildAtomicStore(self.llbuilder, val, ptr, order);
// FIXME(eddyb) Isn't it UB to use `pref` instead of `abi` here?
// Also see `atomic_load` for more context.
llvm::LLVMSetAlignment(store, align.pref() as c_uint);
// LLVM requires the alignment of atomic stores to be at least the size of the type.
llvm::LLVMSetAlignment(store, size.bytes() as c_uint);
}
}