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//@ compile-flags: -Cno-prepopulate-passes -Copt-level=0
#![crate_type = "lib"]
#[no_mangle]
pub fn demo_for_i32() {
generic_impl::<i32>();
}
// Two important things here:
// - We replace the "then" block with `unreachable` to avoid linking problems
// - We neither declare nor define the `big_impl` that said block "calls".
// CHECK-LABEL: ; skip_mono_inside_if_false::generic_impl
// CHECK: start:
// CHECK-NEXT: br label %[[ELSE_BRANCH:bb[0-9]+]]
// CHECK: [[ELSE_BRANCH]]:
// CHECK-NEXT: call skip_mono_inside_if_false::small_impl
// CHECK: bb{{[0-9]+}}:
// CHECK-NEXT: ret void
// CHECK: bb{{[0-9+]}}:
// CHECK-NEXT: unreachable
fn generic_impl<T>() {
trait MagicTrait {
const IS_BIG: bool;
}
impl<T> MagicTrait for T {
const IS_BIG: bool = std::mem::size_of::<T>() > 10;
}
if T::IS_BIG {
big_impl::<T>();
} else {
small_impl::<T>();
}
}
#[inline(never)]
fn small_impl<T>() {}
#[inline(never)]
fn big_impl<T>() {}
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