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mod cast;
mod const_eval;
mod eval_context;
mod place;
mod machine;
mod memory;
mod operator;
mod step;
mod terminator;
mod traits;
pub use self::eval_context::{EvalContext, Frame, StackPopCleanup,
TyAndPacked, ValTy};
pub use self::place::{Place, PlaceExtra};
pub use self::memory::{Memory, MemoryKind, HasMemory};
pub use self::const_eval::{
eval_promoted,
mk_borrowck_eval_cx,
mk_eval_cx,
CompileTimeEvaluator,
const_value_to_allocation_provider,
const_eval_provider,
const_val_field,
const_variant_index,
value_to_const_value,
};
pub use self::machine::Machine;
pub use self::memory::{write_target_uint, write_target_int, read_target_uint};
use rustc::mir::interpret::{EvalResult, EvalErrorKind};
use rustc::ty::{Ty, TyCtxt, ParamEnv};
pub fn sign_extend<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, value: u128, ty: Ty<'tcx>) -> EvalResult<'tcx, u128> {
let param_env = ParamEnv::empty();
let layout = tcx.layout_of(param_env.and(ty)).map_err(|layout| EvalErrorKind::Layout(layout))?;
let size = layout.size.bits();
assert!(layout.abi.is_signed());
let shift = 128 - size;
Ok((((value << shift) as i128) >> shift) as u128)
}
pub fn truncate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, value: u128, ty: Ty<'tcx>) -> EvalResult<'tcx, u128> {
let param_env = ParamEnv::empty();
let layout = tcx.layout_of(param_env.and(ty)).map_err(|layout| EvalErrorKind::Layout(layout))?;
let size = layout.size.bits();
let shift = 128 - size;
Ok((value << shift) >> shift)
}