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#![allow(unknown_lints)]
use ty::layout::{HasDataLayout, Size};
use ty::subst::Substs;
use hir::def_id::DefId;
use super::{EvalResult, Pointer, PointerArithmetic, Allocation, AllocId, sign_extend, truncate};
#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, RustcEncodable, RustcDecodable, Hash)]
pub enum ConstValue<'tcx> {
Unevaluated(DefId, &'tcx Substs<'tcx>),
Scalar(Scalar),
ScalarPair(Scalar, ScalarMaybeUndef),
ByRef(AllocId, &'tcx Allocation, Size),
}
impl<'tcx> ConstValue<'tcx> {
#[inline]
pub fn try_to_scalar(&self) -> Option<Scalar> {
match *self {
ConstValue::Unevaluated(..) |
ConstValue::ByRef(..) |
ConstValue::ScalarPair(..) => None,
ConstValue::Scalar(val) => Some(val),
}
}
#[inline]
pub fn try_to_bits(&self, size: Size) -> Option<u128> {
self.try_to_scalar()?.to_bits(size).ok()
}
#[inline]
pub fn try_to_ptr(&self) -> Option<Pointer> {
self.try_to_scalar()?.to_ptr().ok()
}
#[inline]
pub fn new_slice(
val: Scalar,
len: u64,
cx: impl HasDataLayout
) -> Self {
ConstValue::ScalarPair(val, Scalar::Bits {
bits: len as u128,
size: cx.data_layout().pointer_size.bytes() as u8,
}.into())
}
#[inline]
pub fn new_dyn_trait(val: Scalar, vtable: Pointer) -> Self {
ConstValue::ScalarPair(val, Scalar::Ptr(vtable).into())
}
}
impl<'tcx> Scalar {
#[inline]
pub fn ptr_null(cx: impl HasDataLayout) -> Self {
Scalar::Bits {
bits: 0,
size: cx.data_layout().pointer_size.bytes() as u8,
}
}
#[inline]
pub fn zst() -> Self {
Scalar::Bits { bits: 0, size: 0 }
}
#[inline]
pub fn ptr_signed_offset(self, i: i64, cx: impl HasDataLayout) -> EvalResult<'tcx, Self> {
let layout = cx.data_layout();
match self {
Scalar::Bits { bits, size } => {
assert_eq!(size as u64, layout.pointer_size.bytes());
Ok(Scalar::Bits {
bits: layout.signed_offset(bits as u64, i)? as u128,
size,
})
}
Scalar::Ptr(ptr) => ptr.signed_offset(i, layout).map(Scalar::Ptr),
}
}
#[inline]
pub fn ptr_offset(self, i: Size, cx: impl HasDataLayout) -> EvalResult<'tcx, Self> {
let layout = cx.data_layout();
match self {
Scalar::Bits { bits, size } => {
assert_eq!(size as u64, layout.pointer_size.bytes());
Ok(Scalar::Bits {
bits: layout.offset(bits as u64, i.bytes())? as u128,
size,
})
}
Scalar::Ptr(ptr) => ptr.offset(i, layout).map(Scalar::Ptr),
}
}
#[inline]
pub fn ptr_wrapping_signed_offset(self, i: i64, cx: impl HasDataLayout) -> Self {
let layout = cx.data_layout();
match self {
Scalar::Bits { bits, size } => {
assert_eq!(size as u64, layout.pointer_size.bytes());
Scalar::Bits {
bits: layout.wrapping_signed_offset(bits as u64, i) as u128,
size,
}
}
Scalar::Ptr(ptr) => Scalar::Ptr(ptr.wrapping_signed_offset(i, layout)),
}
}
#[inline]
pub fn is_null_ptr(self, cx: impl HasDataLayout) -> bool {
match self {
Scalar::Bits { bits, size } => {
assert_eq!(size as u64, cx.data_layout().pointer_size.bytes());
bits == 0
},
Scalar::Ptr(_) => false,
}
}
#[inline]
pub fn is_null(self) -> bool {
match self {
Scalar::Bits { bits, .. } => bits == 0,
Scalar::Ptr(_) => false
}
}
#[inline]
pub fn from_bool(b: bool) -> Self {
Scalar::Bits { bits: b as u128, size: 1 }
}
#[inline]
pub fn from_char(c: char) -> Self {
Scalar::Bits { bits: c as u128, size: 4 }
}
#[inline]
pub fn from_uint(i: impl Into<u128>, size: Size) -> Self {
let i = i.into();
debug_assert_eq!(truncate(i, size), i,
"Unsigned value {} does not fit in {} bits", i, size.bits());
Scalar::Bits { bits: i, size: size.bytes() as u8 }
}
#[inline]
pub fn from_int(i: impl Into<i128>, size: Size) -> Self {
let i = i.into();
let truncated = truncate(i as u128, size);
debug_assert_eq!(sign_extend(truncated, size) as i128, i,
"Signed value {} does not fit in {} bits", i, size.bits());
Scalar::Bits { bits: truncated, size: size.bytes() as u8 }
}
#[inline]
pub fn from_f32(f: f32) -> Self {
Scalar::Bits { bits: f.to_bits() as u128, size: 4 }
}
#[inline]
pub fn from_f64(f: f64) -> Self {
Scalar::Bits { bits: f.to_bits() as u128, size: 8 }
}
#[inline]
pub fn to_bits(self, target_size: Size) -> EvalResult<'tcx, u128> {
match self {
Scalar::Bits { bits, size } => {
assert_eq!(target_size.bytes(), size as u64);
assert_ne!(size, 0, "to_bits cannot be used with zsts");
Ok(bits)
}
Scalar::Ptr(_) => err!(ReadPointerAsBytes),
}
}
#[inline]
pub fn to_ptr(self) -> EvalResult<'tcx, Pointer> {
match self {
Scalar::Bits { bits: 0, .. } => err!(InvalidNullPointerUsage),
Scalar::Bits { .. } => err!(ReadBytesAsPointer),
Scalar::Ptr(p) => Ok(p),
}
}
#[inline]
pub fn is_bits(self) -> bool {
match self {
Scalar::Bits { .. } => true,
_ => false,
}
}
#[inline]
pub fn is_ptr(self) -> bool {
match self {
Scalar::Ptr(_) => true,
_ => false,
}
}
pub fn to_bool(self) -> EvalResult<'tcx, bool> {
match self {
Scalar::Bits { bits: 0, size: 1 } => Ok(false),
Scalar::Bits { bits: 1, size: 1 } => Ok(true),
_ => err!(InvalidBool),
}
}
pub fn to_char(self) -> EvalResult<'tcx, char> {
let val = self.to_u32()?;
match ::std::char::from_u32(val) {
Some(c) => Ok(c),
None => err!(InvalidChar(val as u128)),
}
}
pub fn to_u8(self) -> EvalResult<'static, u8> {
let sz = Size::from_bits(8);
let b = self.to_bits(sz)?;
assert_eq!(b as u8 as u128, b);
Ok(b as u8)
}
pub fn to_u32(self) -> EvalResult<'static, u32> {
let sz = Size::from_bits(32);
let b = self.to_bits(sz)?;
assert_eq!(b as u32 as u128, b);
Ok(b as u32)
}
pub fn to_u64(self) -> EvalResult<'static, u64> {
let sz = Size::from_bits(64);
let b = self.to_bits(sz)?;
assert_eq!(b as u64 as u128, b);
Ok(b as u64)
}
pub fn to_usize(self, cx: impl HasDataLayout) -> EvalResult<'static, u64> {
let b = self.to_bits(cx.data_layout().pointer_size)?;
assert_eq!(b as u64 as u128, b);
Ok(b as u64)
}
pub fn to_i8(self) -> EvalResult<'static, i8> {
let sz = Size::from_bits(8);
let b = self.to_bits(sz)?;
let b = sign_extend(b, sz) as i128;
assert_eq!(b as i8 as i128, b);
Ok(b as i8)
}
pub fn to_i32(self) -> EvalResult<'static, i32> {
let sz = Size::from_bits(32);
let b = self.to_bits(sz)?;
let b = sign_extend(b, sz) as i128;
assert_eq!(b as i32 as i128, b);
Ok(b as i32)
}
pub fn to_i64(self) -> EvalResult<'static, i64> {
let sz = Size::from_bits(64);
let b = self.to_bits(sz)?;
let b = sign_extend(b, sz) as i128;
assert_eq!(b as i64 as i128, b);
Ok(b as i64)
}
pub fn to_isize(self, cx: impl HasDataLayout) -> EvalResult<'static, i64> {
let b = self.to_bits(cx.data_layout().pointer_size)?;
let b = sign_extend(b, cx.data_layout().pointer_size) as i128;
assert_eq!(b as i64 as i128, b);
Ok(b as i64)
}
#[inline]
pub fn to_f32(self) -> EvalResult<'static, f32> {
Ok(f32::from_bits(self.to_u32()?))
}
#[inline]
pub fn to_f64(self) -> EvalResult<'static, f64> {
Ok(f64::from_bits(self.to_u64()?))
}
}
impl From<Pointer> for Scalar {
#[inline(always)]
fn from(ptr: Pointer) -> Self {
Scalar::Ptr(ptr)
}
}
#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, RustcEncodable, RustcDecodable, Hash)]
pub enum Scalar<Id=AllocId> {
Bits {
size: u8,
bits: u128,
},
Ptr(Pointer<Id>),
}
#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, RustcEncodable, RustcDecodable, Hash)]
pub enum ScalarMaybeUndef<Id=AllocId> {
Scalar(Scalar<Id>),
Undef,
}
impl From<Scalar> for ScalarMaybeUndef {
#[inline(always)]
fn from(s: Scalar) -> Self {
ScalarMaybeUndef::Scalar(s)
}
}
impl<'tcx> ScalarMaybeUndef {
#[inline]
pub fn not_undef(self) -> EvalResult<'static, Scalar> {
match self {
ScalarMaybeUndef::Scalar(scalar) => Ok(scalar),
ScalarMaybeUndef::Undef => err!(ReadUndefBytes(Size::from_bytes(0))),
}
}
#[inline(always)]
pub fn to_ptr(self) -> EvalResult<'tcx, Pointer> {
self.not_undef()?.to_ptr()
}
#[inline(always)]
pub fn to_bits(self, target_size: Size) -> EvalResult<'tcx, u128> {
self.not_undef()?.to_bits(target_size)
}
#[inline(always)]
pub fn to_bool(self) -> EvalResult<'tcx, bool> {
self.not_undef()?.to_bool()
}
#[inline(always)]
pub fn to_char(self) -> EvalResult<'tcx, char> {
self.not_undef()?.to_char()
}
#[inline(always)]
pub fn to_f32(self) -> EvalResult<'tcx, f32> {
self.not_undef()?.to_f32()
}
#[inline(always)]
pub fn to_f64(self) -> EvalResult<'tcx, f64> {
self.not_undef()?.to_f64()
}
#[inline(always)]
pub fn to_u8(self) -> EvalResult<'tcx, u8> {
self.not_undef()?.to_u8()
}
#[inline(always)]
pub fn to_u32(self) -> EvalResult<'tcx, u32> {
self.not_undef()?.to_u32()
}
#[inline(always)]
pub fn to_u64(self) -> EvalResult<'tcx, u64> {
self.not_undef()?.to_u64()
}
#[inline(always)]
pub fn to_usize(self, cx: impl HasDataLayout) -> EvalResult<'tcx, u64> {
self.not_undef()?.to_usize(cx)
}
#[inline(always)]
pub fn to_i8(self) -> EvalResult<'tcx, i8> {
self.not_undef()?.to_i8()
}
#[inline(always)]
pub fn to_i32(self) -> EvalResult<'tcx, i32> {
self.not_undef()?.to_i32()
}
#[inline(always)]
pub fn to_i64(self) -> EvalResult<'tcx, i64> {
self.not_undef()?.to_i64()
}
#[inline(always)]
pub fn to_isize(self, cx: impl HasDataLayout) -> EvalResult<'tcx, i64> {
self.not_undef()?.to_isize(cx)
}
}