57 lines
967 B
Rust
57 lines
967 B
Rust
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#![crate_name="interesting"]
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#![crate_type="rlib"]
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extern crate opaque;
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#[no_mangle]
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pub fn function_called_always() {
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opaque::opaque_f1();
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}
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#[no_mangle]
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pub fn function_called_never() {
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opaque::opaque_f2();
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}
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#[no_mangle]
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pub fn call_a_bunch_of_functions(fns: &[fn()]) {
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// Indirect call promotion transforms the below into something like
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//
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// for f in fns {
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// if f == function_called_always {
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// function_called_always()
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// } else {
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// f();
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// }
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// }
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//
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// where `function_called_always` actually gets inlined too.
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for f in fns {
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f();
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}
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}
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pub trait Foo {
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fn foo(&self);
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}
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impl Foo for u32 {
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#[no_mangle]
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fn foo(&self) {
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opaque::opaque_f2();
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}
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}
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#[no_mangle]
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pub fn call_a_bunch_of_trait_methods(trait_objects: &[&dyn Foo]) {
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// Same as above, just with vtables in between
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for x in trait_objects {
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x.foo();
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}
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}
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