143f39362a
Today we're making LLVM do a bunch of extra work for every enum you match on, even trivial stuff like `Option<bool>`. Let's not.
37 lines
738 B
Rust
37 lines
738 B
Rust
//@ compile-flags: -O
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#![crate_type = "lib"]
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#![feature(core_intrinsics)]
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use std::intrinsics::cold_path;
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#[inline(never)]
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#[no_mangle]
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pub fn path_a() {
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println!("path a");
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}
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#[inline(never)]
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#[no_mangle]
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pub fn path_b() {
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println!("path b");
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}
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#[no_mangle]
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pub fn test(x: Option<bool>) {
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if let Some(_) = x {
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path_a();
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} else {
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cold_path();
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path_b();
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}
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// CHECK-LABEL: void @test(i8{{.+}}%x)
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// CHECK: %[[IS_NONE:.+]] = icmp eq i8 %x, 2
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// CHECK: br i1 %[[IS_NONE]], label %bb2, label %bb1, !prof ![[NUM:[0-9]+]]
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// CHECK: bb1:
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// CHECK: path_a
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// CHECK: bb2:
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// CHECK: path_b
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}
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// CHECK: ![[NUM]] = !{!"branch_weights", {{(!"expected", )?}}i32 1, i32 2000}
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