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55 lines
2.1 KiB
Rust
55 lines
2.1 KiB
Rust
//@ compile-flags: -C no-prepopulate-passes
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// Check that we use undef (and not zero) for uninitialized bytes in constants.
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#![crate_type = "lib"]
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use std::mem::MaybeUninit;
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pub struct PartiallyUninit {
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x: u32,
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y: MaybeUninit<[u8; 10]>,
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}
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// CHECK: [[FULLY_UNINIT:@[0-9]+]] = private unnamed_addr constant <{ [10 x i8] }> undef
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// CHECK: [[PARTIALLY_UNINIT:@[0-9]+]] = private unnamed_addr constant <{ [4 x i8], [12 x i8] }> <{ [4 x i8] c"{{\\EF\\BE\\AD\\DE|\\DE\\AD\\BE\\EF}}", [12 x i8] undef }>, align 4
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// This shouldn't contain undef, since it contains more chunks
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// than the default value of uninit_const_chunk_threshold.
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// CHECK: [[UNINIT_PADDING_HUGE:@[0-9]+]] = private unnamed_addr constant <{ [32768 x i8] }> <{ [32768 x i8] c"{{.+}}" }>, align 4
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// CHECK: [[FULLY_UNINIT_HUGE:@[0-9]+]] = private unnamed_addr constant <{ [16384 x i8] }> undef
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// CHECK-LABEL: @fully_uninit
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#[no_mangle]
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pub const fn fully_uninit() -> MaybeUninit<[u8; 10]> {
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const M: MaybeUninit<[u8; 10]> = MaybeUninit::uninit();
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 1 %_0, ptr align 1 {{.*}}[[FULLY_UNINIT]]{{.*}}, i{{(32|64)}} 10, i1 false)
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M
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}
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// CHECK-LABEL: @partially_uninit
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#[no_mangle]
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pub const fn partially_uninit() -> PartiallyUninit {
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const X: PartiallyUninit = PartiallyUninit { x: 0xdeadbeef, y: MaybeUninit::uninit() };
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 4 %_0, ptr align 4 {{.*}}[[PARTIALLY_UNINIT]]{{.*}}, i{{(32|64)}} 16, i1 false)
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X
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}
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// CHECK-LABEL: @uninit_padding_huge
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#[no_mangle]
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pub const fn uninit_padding_huge() -> [(u32, u8); 4096] {
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const X: [(u32, u8); 4096] = [(123, 45); 4096];
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 4 %_0, ptr align 4 {{.*}}[[UNINIT_PADDING_HUGE]]{{.*}}, i{{(32|64)}} 32768, i1 false)
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X
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}
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// CHECK-LABEL: @fully_uninit_huge
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#[no_mangle]
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pub const fn fully_uninit_huge() -> MaybeUninit<[u32; 4096]> {
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const F: MaybeUninit<[u32; 4096]> = MaybeUninit::uninit();
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// CHECK: call void @llvm.memcpy.{{.+}}(ptr align 4 %_0, ptr align 4 {{.*}}[[FULLY_UNINIT_HUGE]]{{.*}}, i{{(32|64)}} 16384, i1 false)
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F
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}
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