rust/tests/codegen/match-optimized.rs

61 lines
1.5 KiB
Rust

//@ compile-flags: -C no-prepopulate-passes -O
#![crate_type = "lib"]
pub enum E {
A,
B,
C,
}
// CHECK-LABEL: @exhaustive_match
#[no_mangle]
pub fn exhaustive_match(e: E) -> u8 {
// CHECK: switch{{.*}}, label %[[OTHERWISE:[a-zA-Z0-9_]+]] [
// CHECK-NEXT: i[[TY:[0-9]+]] [[DISCR:[0-9]+]], label %[[A:[a-zA-Z0-9_]+]]
// CHECK-NEXT: i[[TY:[0-9]+]] [[DISCR:[0-9]+]], label %[[B:[a-zA-Z0-9_]+]]
// CHECK-NEXT: i[[TY:[0-9]+]] [[DISCR:[0-9]+]], label %[[C:[a-zA-Z0-9_]+]]
// CHECK-NEXT: ]
// CHECK: [[OTHERWISE]]:
// CHECK-NEXT: unreachable
//
// CHECK: [[A]]:
// CHECK-NEXT: store i8 0, ptr %_0, align 1
// CHECK-NEXT: br label %[[EXIT:[a-zA-Z0-9_]+]]
// CHECK: [[B]]:
// CHECK-NEXT: store i8 1, ptr %_0, align 1
// CHECK-NEXT: br label %[[EXIT]]
// CHECK: [[C]]:
// CHECK-NEXT: store i8 3, ptr %_0, align 1
// CHECK-NEXT: br label %[[EXIT]]
match e {
E::A => 0,
E::B => 1,
E::C => 3,
}
}
#[repr(u16)]
pub enum E2 {
A = 13,
B = 42,
}
// For optimized code we produce a switch with an unreachable target as the `otherwise` so LLVM
// knows the possible values. Compare with `tests/codegen/match-unoptimized.rs`.
// CHECK-LABEL: @exhaustive_match_2
#[no_mangle]
pub fn exhaustive_match_2(e: E2) -> u8 {
// CHECK: switch i16 %{{.+}}, label %[[UNREACH:.+]] [
// CHECK-NEXT: i16 13,
// CHECK-NEXT: i16 42,
// CHECK-NEXT: ]
// CHECK: [[UNREACH]]:
// CHECK-NEXT: unreachable
match e {
E2::A => 0,
E2::B => 1,
}
}