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			94 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			94 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| // ignore-debug: the debug assertions get in the way
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| // compile-flags: -O -Z merge-functions=disabled
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| // min-llvm-version: 16
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| #![crate_type = "lib"]
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| 
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| // Ensure that trivial casts of vec elements are O(1)
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| 
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| pub struct Wrapper<T>(T);
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| 
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| // previously repr(C) caused the optimization to fail
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| #[repr(C)]
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| pub struct Foo {
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|     a: u64,
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|     b: u64,
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|     c: u64,
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|     d: u64,
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| }
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| 
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| // implementing Copy exercises the TrustedRandomAccess specialization inside the in-place
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| // specialization
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| #[derive(Copy, Clone)]
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| pub struct Bar {
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|     a: u64,
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|     b: u64,
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|     c: u64,
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|     d: u64,
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| }
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| 
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| // this exercises the try-fold codepath
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| pub struct Baz {
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|     a: u64,
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|     b: u64,
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|     c: u64,
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|     d: u64,
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| }
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| 
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| // CHECK-LABEL: @vec_iterator_cast_primitive
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| #[no_mangle]
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| pub fn vec_iterator_cast_primitive(vec: Vec<i8>) -> Vec<u8> {
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|     // CHECK-NOT: loop
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|     // CHECK-NOT: call
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|     vec.into_iter().map(|e| e as u8).collect()
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| }
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| 
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| // CHECK-LABEL: @vec_iterator_cast_wrapper
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| #[no_mangle]
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| pub fn vec_iterator_cast_wrapper(vec: Vec<u8>) -> Vec<Wrapper<u8>> {
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|     // CHECK-NOT: loop
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|     // CHECK-NOT: call
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|     vec.into_iter().map(|e| Wrapper(e)).collect()
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| }
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| 
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| // CHECK-LABEL: @vec_iterator_cast_unwrap
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| #[no_mangle]
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| pub fn vec_iterator_cast_unwrap(vec: Vec<Wrapper<u8>>) -> Vec<u8> {
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|     // CHECK-NOT: loop
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|     // CHECK-NOT: call
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|     vec.into_iter().map(|e| e.0).collect()
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| }
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| 
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| // CHECK-LABEL: @vec_iterator_cast_aggregate
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| #[no_mangle]
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| pub fn vec_iterator_cast_aggregate(vec: Vec<[u64; 4]>) -> Vec<Foo> {
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|     // CHECK-NOT: loop
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|     // CHECK-NOT: call
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|     vec.into_iter().map(|e| unsafe { std::mem::transmute(e) }).collect()
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| }
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| 
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| // CHECK-LABEL: @vec_iterator_cast_deaggregate_tra
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| #[no_mangle]
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| pub fn vec_iterator_cast_deaggregate_tra(vec: Vec<Bar>) -> Vec<[u64; 4]> {
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|     // CHECK-NOT: loop
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|     // CHECK-NOT: call
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| 
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|     // Safety: For the purpose of this test we assume that Bar layout matches [u64; 4].
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|     // This currently is not guaranteed for repr(Rust) types, but it happens to work here and
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|     // the UCG may add additional guarantees for homogenous types in the future that would make this
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|     // correct.
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|     vec.into_iter().map(|e| unsafe { std::mem::transmute(e) }).collect()
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| }
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| 
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| // CHECK-LABEL: @vec_iterator_cast_deaggregate_fold
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| #[no_mangle]
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| pub fn vec_iterator_cast_deaggregate_fold(vec: Vec<Baz>) -> Vec<[u64; 4]> {
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|     // CHECK-NOT: loop
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|     // CHECK-NOT: call
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| 
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|     // Safety: For the purpose of this test we assume that Bar layout matches [u64; 4].
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|     // This currently is not guaranteed for repr(Rust) types, but it happens to work here and
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|     // the UCG may add additional guarantees for homogenous types in the future that would make this
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|     // correct.
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|     vec.into_iter().map(|e| unsafe { std::mem::transmute(e) }).collect()
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| }
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