rust/tests/mir-opt/unreachable_enum_branching.rs

219 lines
6.2 KiB
Rust

//@ unit-test: UnreachableEnumBranching
// EMIT_MIR_FOR_EACH_PANIC_STRATEGY
enum Empty {}
// test matching an enum with uninhabited variants
enum Test1 {
A(Empty),
B(Empty),
C,
}
// test an enum where the discriminants don't match the variant indexes
// (the optimization should do nothing here)
enum Test2 {
D = 4,
E = 5,
}
// test matching an enum with uninhabited variants and multiple inhabited
enum Test3 {
A(Empty),
B(Empty),
C,
D,
}
enum Test4 {
A(i32),
B(i32),
C,
D,
}
#[repr(i8)]
enum Test5<T> {
A(T) = -1,
B(T) = 0,
C = 5,
D = 3,
}
struct Plop {
xx: u32,
test3: Test3,
}
// EMIT_MIR unreachable_enum_branching.simple.UnreachableEnumBranching.diff
fn simple() {
// CHECK-LABEL: fn simple(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [0: [[unreachable:bb.*]], 1: [[unreachable]], 2: bb2, otherwise: [[unreachable]]];
// CHECK: [[unreachable]]: {
// CHECK-NEXT: unreachable;
match Test1::C {
Test1::A(_) => "A(Empty)",
Test1::B(_) => "B(Empty)",
Test1::C => "C",
};
}
// EMIT_MIR unreachable_enum_branching.custom_discriminant.UnreachableEnumBranching.diff
fn custom_discriminant() {
// CHECK-LABEL: fn custom_discriminant(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [4: bb3, 5: bb2, otherwise: [[unreachable:bb.*]]];
// CHECK: [[unreachable]]: {
// CHECK-NEXT: unreachable;
match Test2::D {
Test2::D => "D",
Test2::E => "E",
};
}
// EMIT_MIR unreachable_enum_branching.otherwise_t1.UnreachableEnumBranching.diff
fn otherwise_t1() {
// CHECK-LABEL: fn otherwise_t1(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [0: bb5, 1: bb5, 2: bb1, otherwise: [[unreachable:bb.*]]];
// CHECK: [[unreachable]]: {
// CHECK-NEXT: unreachable;
match Test1::C {
Test1::A(_) => "A(Empty)",
Test1::B(_) => "B(Empty)",
_ => "C",
};
}
// EMIT_MIR unreachable_enum_branching.otherwise_t2.UnreachableEnumBranching.diff
fn otherwise_t2() {
// CHECK-LABEL: fn otherwise_t2(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [4: bb2, 5: bb1, otherwise: [[unreachable:bb.*]]];
// CHECK: [[unreachable]]: {
// CHECK-NEXT: unreachable;
match Test2::D {
Test2::D => "D",
_ => "E",
};
}
// EMIT_MIR unreachable_enum_branching.otherwise_t3.UnreachableEnumBranching.diff
fn otherwise_t3() {
// CHECK-LABEL: fn otherwise_t3(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [0: bb5, 1: bb5, otherwise: bb1];
// CHECK: bb1: {
// CHECK-NOT: unreachable;
// CHECK: }
// CHECK: bb5: {
// CHECK-NEXT: unreachable;
match Test3::C {
Test3::A(_) => "A(Empty)",
Test3::B(_) => "B(Empty)",
_ => "C",
};
}
// EMIT_MIR unreachable_enum_branching.otherwise_t4_unreachable_default.UnreachableEnumBranching.diff
fn otherwise_t4_unreachable_default() {
// CHECK-LABEL: fn otherwise_t4_unreachable_default(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [0: bb2, 1: bb3, 2: bb4, 3: bb1, otherwise: [[unreachable:bb.*]]];
// CHECK: [[unreachable]]: {
// CHECK-NEXT: unreachable;
match Test4::C {
Test4::A(_) => "A(i32)",
Test4::B(_) => "B(i32)",
Test4::C => "C",
_ => "D",
};
}
// EMIT_MIR unreachable_enum_branching.otherwise_t4_unreachable_default_2.UnreachableEnumBranching.diff
fn otherwise_t4_unreachable_default_2() {
// CHECK-LABEL: fn otherwise_t4_unreachable_default_2(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [0: bb2, 1: bb5, 2: bb6, 3: bb1, otherwise: [[unreachable:bb.*]]];
// CHECK: [[unreachable]]: {
// CHECK-NEXT: unreachable;
match Test4::C {
Test4::A(1) => "A(1)",
Test4::A(2) => "A(2)",
Test4::B(_) => "B(i32)",
Test4::C => "C",
_ => "A(other)D",
};
}
// EMIT_MIR unreachable_enum_branching.otherwise_t4.UnreachableEnumBranching.diff
fn otherwise_t4() {
// CHECK-LABEL: fn otherwise_t4(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [0: bb2, 1: bb3, otherwise: [[unreachable:bb.*]]];
// CHECK: [[unreachable]]: {
// CHECK-NOT: unreachable;
// CHECK: }
match Test4::C {
Test4::A(_) => "A(i32)",
Test4::B(_) => "B(i32)",
_ => "CD",
};
}
// EMIT_MIR unreachable_enum_branching.otherwise_t5_unreachable_default.UnreachableEnumBranching.diff
fn otherwise_t5_unreachable_default<T>() {
// CHECK-LABEL: fn otherwise_t5_unreachable_default(
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [255: bb2, 0: bb3, 5: bb4, 3: bb1, otherwise: [[unreachable:bb.*]]];
// CHECK: [[unreachable]]: {
// CHECK-NEXT: unreachable;
match Test5::<T>::C {
Test5::A(_) => "A(T)",
Test5::B(_) => "B(T)",
Test5::C => "C",
_ => "D",
};
}
// EMIT_MIR unreachable_enum_branching.byref.UnreachableEnumBranching.diff
fn byref() {
// CHECK-LABEL: fn byref(
let plop = Plop { xx: 51, test3: Test3::C };
// CHECK: [[ref_discr:_.*]] = discriminant((*
// CHECK: switchInt(move [[ref_discr]]) -> [0: [[unreachable:bb.*]], 1: [[unreachable]], 2: bb5, 3: bb2, otherwise: [[unreachable]]];
match &plop.test3 {
Test3::A(_) => "A(Empty)",
Test3::B(_) => "B(Empty)",
Test3::C => "C",
Test3::D => "D",
};
// CHECK: [[unreachable]]: {
// CHECK-NEXT: unreachable;
// CHECK: [[discr:_.*]] = discriminant(
// CHECK: switchInt(move [[discr]]) -> [0: [[unreachable]], 1: [[unreachable]], 2: bb10, 3: bb7, otherwise: [[unreachable]]];
match plop.test3 {
Test3::A(_) => "A(Empty)",
Test3::B(_) => "B(Empty)",
Test3::C => "C",
Test3::D => "D",
};
}
fn main() {
simple();
custom_discriminant();
otherwise_t1();
otherwise_t2();
otherwise_t3();
otherwise_t4_unreachable_default();
otherwise_t4_unreachable_default_2();
otherwise_t4();
otherwise_t5_unreachable_default::<i32>();
byref();
}