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| author | Guillaume Gomez <guillaume1.gomez@gmail.com> | 2025-07-21 14:34:12 +0200 | 
|---|---|---|
| committer | Guillaume Gomez <guillaume1.gomez@gmail.com> | 2025-07-22 14:28:48 +0200 | 
| commit | a27f3e3fd1e4d16160f8885b6b06665b5319f56c (patch) | |
| tree | b033935392cbadf6f85d2dbddf433a88e323aeeb /tests/codegen-llvm/box-uninit-bytes.rs | |
| parent | ed93c1783b404d728d4809973a0550eb33cd293f (diff) | |
| download | rust-a27f3e3fd1e4d16160f8885b6b06665b5319f56c.tar.gz rust-a27f3e3fd1e4d16160f8885b6b06665b5319f56c.zip  | |
Rename `tests/codegen` into `tests/codegen-llvm`
Diffstat (limited to 'tests/codegen-llvm/box-uninit-bytes.rs')
| -rw-r--r-- | tests/codegen-llvm/box-uninit-bytes.rs | 46 | 
1 files changed, 46 insertions, 0 deletions
diff --git a/tests/codegen-llvm/box-uninit-bytes.rs b/tests/codegen-llvm/box-uninit-bytes.rs new file mode 100644 index 00000000000..0cc01148595 --- /dev/null +++ b/tests/codegen-llvm/box-uninit-bytes.rs @@ -0,0 +1,46 @@ +//@ compile-flags: -Copt-level=3 +#![crate_type = "lib"] + +use std::mem::MaybeUninit; + +// Boxing a `MaybeUninit` value should not copy junk from the stack +#[no_mangle] +pub fn box_uninitialized() -> Box<MaybeUninit<usize>> { + // CHECK-LABEL: @box_uninitialized + // CHECK-NOT: store + // CHECK-NOT: alloca + // CHECK-NOT: memcpy + // CHECK-NOT: memset + Box::new(MaybeUninit::uninit()) +} + +// https://github.com/rust-lang/rust/issues/58201 +#[no_mangle] +pub fn box_uninitialized2() -> Box<MaybeUninit<[usize; 1024 * 1024]>> { + // CHECK-LABEL: @box_uninitialized2 + // CHECK-NOT: store + // CHECK-NOT: alloca + // CHECK-NOT: memcpy + // CHECK-NOT: memset + Box::new(MaybeUninit::uninit()) +} + +#[repr(align(1024))] +pub struct LotsaPadding(usize); + +// Boxing a value with padding should not copy junk from the stack +#[no_mangle] +pub fn box_lotsa_padding() -> Box<LotsaPadding> { + // CHECK-LABEL: @box_lotsa_padding + // CHECK-NOT: alloca + // CHECK-NOT: getelementptr + // CHECK-NOT: memcpy + // CHECK-NOT: memset + Box::new(LotsaPadding(42)) +} + +// Hide the `allocalign` attribute in the declaration of __rust_alloc +// from the CHECK-NOT above, and also verify the attributes got set reasonably. +// CHECK: declare {{(dso_local )?}}noalias noundef ptr @{{.*}}__rust_alloc(i{{[0-9]+}} noundef, i{{[0-9]+}} allocalign noundef) unnamed_addr [[RUST_ALLOC_ATTRS:#[0-9]+]] + +// CHECK-DAG: attributes [[RUST_ALLOC_ATTRS]] = { {{.*}} allockind("alloc,uninitialized,aligned") allocsize(0) {{(uwtable )?}}"alloc-family"="__rust_alloc" {{.*}} }  | 
