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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/slice-init.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/slice-init.rs')
| -rw-r--r-- | tests/codegen-llvm/slice-init.rs | 108 | 
1 files changed, 108 insertions, 0 deletions
| diff --git a/tests/codegen-llvm/slice-init.rs b/tests/codegen-llvm/slice-init.rs new file mode 100644 index 00000000000..950e0b0c10d --- /dev/null +++ b/tests/codegen-llvm/slice-init.rs @@ -0,0 +1,108 @@ +//@ compile-flags: -C no-prepopulate-passes + +#![crate_type = "lib"] + +// CHECK-LABEL: @zero_sized_elem +#[no_mangle] +pub fn zero_sized_elem() { + // CHECK-NOT: br label %repeat_loop_header{{.*}} + // CHECK-NOT: call void @llvm.memset.p0 + let x = [(); 4]; + opaque(&x); +} + +// CHECK-LABEL: @zero_len_array +#[no_mangle] +pub fn zero_len_array() { + // CHECK-NOT: br label %repeat_loop_header{{.*}} + // CHECK-NOT: call void @llvm.memset.p0 + let x = [4; 0]; + opaque(&x); +} + +// CHECK-LABEL: @byte_array +#[no_mangle] +pub fn byte_array() { + // CHECK: call void @llvm.memset.{{.+}}(ptr {{.*}}, i8 7, i{{[0-9]+}} 4 + // CHECK-NOT: br label %repeat_loop_header{{.*}} + let x = [7u8; 4]; + opaque(&x); +} + +#[allow(dead_code)] +#[derive(Copy, Clone)] +enum Init { + Loop, + Memset, +} + +// CHECK-LABEL: @byte_enum_array +#[no_mangle] +pub fn byte_enum_array() { + // CHECK: call void @llvm.memset.{{.+}}(ptr {{.*}}, i8 {{.*}}, i{{[0-9]+}} 4 + // CHECK-NOT: br label %repeat_loop_header{{.*}} + let x = [Init::Memset; 4]; + opaque(&x); +} + +// CHECK-LABEL: @zeroed_integer_array +#[no_mangle] +pub fn zeroed_integer_array() { + // CHECK: call void @llvm.memset.{{.+}}(ptr {{.*}}, i8 0, i{{[0-9]+}} 16 + // CHECK-NOT: br label %repeat_loop_header{{.*}} + let x = [0u32; 4]; + opaque(&x); +} + +// CHECK-LABEL: @nonzero_integer_array +#[no_mangle] +pub fn nonzero_integer_array() { + // CHECK: br label %repeat_loop_header{{.*}} + // CHECK-NOT: call void @llvm.memset.p0 + let x = [0x1a_2b_3c_4d_u32; 4]; + opaque(&x); +} + +const N: usize = 100; + +// CHECK-LABEL: @u16_init_one_bytes +#[no_mangle] +pub fn u16_init_one_bytes() -> [u16; N] { + // CHECK-NOT: select + // CHECK-NOT: br + // CHECK-NOT: switch + // CHECK-NOT: icmp + // CHECK: call void @llvm.memset.p0 + [const { u16::from_be_bytes([1, 1]) }; N] +} + +// FIXME: undef bytes can just be initialized with the same value as the +// defined bytes, if the defines bytes are all the same. +// CHECK-LABEL: @option_none_init +#[no_mangle] +pub fn option_none_init() -> [Option<u8>; N] { + // CHECK-NOT: select + // CHECK: br label %repeat_loop_header{{.*}} + // CHECK-NOT: switch + // CHECK: icmp + // CHECK-NOT: call void @llvm.memset.p0 + [None; N] +} + +use std::mem::MaybeUninit; + +// FIXME: This could be optimized into a memset. +// Regression test for <https://github.com/rust-lang/rust/issues/137892>. +#[no_mangle] +pub fn half_uninit() -> [(u128, MaybeUninit<u128>); N] { + // CHECK-NOT: select + // CHECK: br label %repeat_loop_header{{.*}} + // CHECK-NOT: switch + // CHECK: icmp + // CHECK-NOT: call void @llvm.memset.p0 + [const { (0, MaybeUninit::uninit()) }; N] +} + +// Use an opaque function to prevent rustc from removing useless drops. +#[inline(never)] +pub fn opaque(_: impl Sized) {} | 
