2f00e86cb5
This optimization depends on inlining for the identity conversions introduced by the lowering of the `?`. To take advantage of `SimplifyArmIdentity`, `-Z mir-opt-level=2` is required because that triggers the inlining MIR optimization.
17 lines
423 B
Rust
17 lines
423 B
Rust
// compile-flags: -C no-prepopulate-passes -Z mir-opt-level=2
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// Ensure that `x?` has no overhead on `Result<T, E>` due to identity `match`es in lowering.
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// This requires inlining to trigger the MIR optimizations in `SimplifyArmIdentity`.
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#![crate_type = "lib"]
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type R = Result<u64, i32>;
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#[no_mangle]
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fn try_identity(x: R) -> R {
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// CHECK: start:
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// CHECK-NOT: br {{.*}}
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// CHECK ret void
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let y = x?;
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Ok(y)
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}
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