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30 lines
1.1 KiB
Rust
30 lines
1.1 KiB
Rust
// compile-flags: -C no-prepopulate-passes -Copt-level=0
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#![crate_type = "lib"]
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// Hack to get the correct size for the length part in slices
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// CHECK: @helper([[USIZE:i[0-9]+]] %_1)
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#[no_mangle]
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pub fn helper(_: usize) {
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}
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// CHECK-LABEL: @no_op_slice_adjustment
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#[no_mangle]
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pub fn no_op_slice_adjustment(x: &[u8]) -> &[u8] {
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// We used to generate an extra alloca and memcpy for the block's trailing expression value, so
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// check that we copy directly to the return value slot
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// CHECK: %0 = insertvalue { {{\[0 x i8\]\*|ptr}}, [[USIZE]] } undef, {{\[0 x i8\]\*|ptr}} %x.0, 0
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// CHECK: %1 = insertvalue { {{\[0 x i8\]\*|ptr}}, [[USIZE]] } %0, [[USIZE]] %x.1, 1
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// CHECK: ret { {{\[0 x i8\]\*|ptr}}, [[USIZE]] } %1
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{ x }
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}
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// CHECK-LABEL: @no_op_slice_adjustment2
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#[no_mangle]
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pub fn no_op_slice_adjustment2(x: &[u8]) -> &[u8] {
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// We used to generate an extra alloca and memcpy for the function's return value, so check
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// that there's no memcpy (the slice is written to sret_slot element-wise)
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// CHECK-NOT: call void @llvm.memcpy.
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no_op_slice_adjustment(x)
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}
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