-#![allow(cast_possible_truncation)]
+// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
-use rustc::lint::LateContext;
-use rustc::hir::def::{Def, PathResolution};
-use rustc_const_eval::lookup_const_by_id;
-use rustc_const_math::{ConstInt, ConstUsize, ConstIsize};
-use rustc::hir::*;
+
+#![allow(clippy::float_cmp)]
+
+use crate::rustc::lint::LateContext;
+use crate::rustc::{span_bug, bug};
+use crate::rustc::hir::def::Def;
+use crate::rustc::hir::*;
+use crate::rustc::ty::{self, Ty, TyCtxt, Instance};
+use crate::rustc::ty::subst::{Subst, Substs};
use std::cmp::Ordering::{self, Equal};
use std::cmp::PartialOrd;
+use std::convert::TryInto;
use std::hash::{Hash, Hasher};
use std::mem;
-use std::ops::Deref;
use std::rc::Rc;
-use syntax::ast::{FloatTy, LitIntType, LitKind, StrStyle, UintTy, IntTy};
-use syntax::ptr::P;
-
-#[derive(Debug, Copy, Clone)]
-pub enum FloatWidth {
- F32,
- F64,
- Any,
-}
-
-impl From<FloatTy> for FloatWidth {
- fn from(ty: FloatTy) -> FloatWidth {
- match ty {
- FloatTy::F32 => FloatWidth::F32,
- FloatTy::F64 => FloatWidth::F64,
- }
- }
-}
+use crate::syntax::ast::{FloatTy, LitKind};
+use crate::syntax::ptr::P;
+use crate::utils::{sext, unsext, clip};
/// A `LitKind`-like enum to fold constant `Expr`s into.
#[derive(Debug, Clone)]
pub enum Constant {
/// a String "abc"
- Str(String, StrStyle),
+ Str(String),
/// a Binary String b"abc"
Binary(Rc<Vec<u8>>),
/// a single char 'a'
Char(char),
- /// an integer, third argument is whether the value is negated
- Int(ConstInt),
- /// a float with given type
- Float(String, FloatWidth),
+ /// an integer's bit representation
+ Int(u128),
+ /// an f32
+ F32(f32),
+ /// an f64
+ F64(f64),
/// true or false
Bool(bool),
/// an array of constants
Vec(Vec<Constant>),
/// also an array, but with only one constant, repeated N times
- Repeat(Box<Constant>, usize),
+ Repeat(Box<Constant>, u64),
/// a tuple of constants
Tuple(Vec<Constant>),
}
-impl Constant {
- /// Convert to `u64` if possible.
- ///
- /// # panics
- ///
- /// If the constant could not be converted to `u64` losslessly.
- fn as_u64(&self) -> u64 {
- if let Constant::Int(val) = *self {
- val.to_u64().expect("negative constant can't be casted to `u64`")
- } else {
- panic!("Could not convert a `{:?}` to `u64`", self);
- }
- }
-}
-
impl PartialEq for Constant {
- fn eq(&self, other: &Constant) -> bool {
+ fn eq(&self, other: &Self) -> bool {
match (self, other) {
- (&Constant::Str(ref ls, ref l_sty), &Constant::Str(ref rs, ref r_sty)) => ls == rs && l_sty == r_sty,
+ (&Constant::Str(ref ls), &Constant::Str(ref rs)) => ls == rs,
(&Constant::Binary(ref l), &Constant::Binary(ref r)) => l == r,
(&Constant::Char(l), &Constant::Char(r)) => l == r,
- (&Constant::Int(l), &Constant::Int(r)) => {
- l.is_negative() == r.is_negative() && l.to_u64_unchecked() == r.to_u64_unchecked()
- }
- (&Constant::Float(ref ls, _), &Constant::Float(ref rs, _)) => {
+ (&Constant::Int(l), &Constant::Int(r)) => l == r,
+ (&Constant::F64(l), &Constant::F64(r)) => {
// we want `Fw32 == FwAny` and `FwAny == Fw64`, by transitivity we must have
// `Fw32 == Fw64` so don’t compare them
- match (ls.parse::<f64>(), rs.parse::<f64>()) {
- // mem::transmute is required to catch non-matching 0.0, -0.0, and NaNs
- (Ok(l), Ok(r)) => unsafe {
- mem::transmute::<f64, u64>(l) == mem::transmute::<f64, u64>(r)
- },
- _ => false,
- }
- }
+ // mem::transmute is required to catch non-matching 0.0, -0.0, and NaNs
+ unsafe { mem::transmute::<f64, u64>(l) == mem::transmute::<f64, u64>(r) }
+ },
+ (&Constant::F32(l), &Constant::F32(r)) => {
+ // we want `Fw32 == FwAny` and `FwAny == Fw64`, by transitivity we must have
+ // `Fw32 == Fw64` so don’t compare them
+ // mem::transmute is required to catch non-matching 0.0, -0.0, and NaNs
+ unsafe { mem::transmute::<f64, u64>(f64::from(l)) == mem::transmute::<f64, u64>(f64::from(r)) }
+ },
(&Constant::Bool(l), &Constant::Bool(r)) => l == r,
- (&Constant::Vec(ref l), &Constant::Vec(ref r)) => l == r,
+ (&Constant::Vec(ref l), &Constant::Vec(ref r)) | (&Constant::Tuple(ref l), &Constant::Tuple(ref r)) => l == r,
(&Constant::Repeat(ref lv, ref ls), &Constant::Repeat(ref rv, ref rs)) => ls == rs && lv == rv,
- (&Constant::Tuple(ref l), &Constant::Tuple(ref r)) => l == r,
- _ => false, //TODO: Are there inter-type equalities?
+ _ => false, // TODO: Are there inter-type equalities?
}
}
}
impl Hash for Constant {
fn hash<H>(&self, state: &mut H)
- where H: Hasher
+ where
+ H: Hasher,
{
match *self {
- Constant::Str(ref s, ref k) => {
+ Constant::Str(ref s) => {
s.hash(state);
- k.hash(state);
- }
+ },
Constant::Binary(ref b) => {
b.hash(state);
- }
+ },
Constant::Char(c) => {
c.hash(state);
- }
+ },
Constant::Int(i) => {
- i.to_u64_unchecked().hash(state);
- i.is_negative().hash(state);
- }
- Constant::Float(ref f, _) => {
- // don’t use the width here because of PartialEq implementation
- if let Ok(f) = f.parse::<f64>() {
- unsafe { mem::transmute::<f64, u64>(f) }.hash(state);
- }
- }
+ i.hash(state);
+ },
+ Constant::F32(f) => {
+ unsafe { mem::transmute::<f64, u64>(f64::from(f)) }.hash(state);
+ },
+ Constant::F64(f) => {
+ unsafe { mem::transmute::<f64, u64>(f) }.hash(state);
+ },
Constant::Bool(b) => {
b.hash(state);
- }
- Constant::Vec(ref v) |
- Constant::Tuple(ref v) => {
+ },
+ Constant::Vec(ref v) | Constant::Tuple(ref v) => {
v.hash(state);
- }
+ },
Constant::Repeat(ref c, l) => {
c.hash(state);
l.hash(state);
- }
+ },
}
}
}
-impl PartialOrd for Constant {
- fn partial_cmp(&self, other: &Constant) -> Option<Ordering> {
- match (self, other) {
- (&Constant::Str(ref ls, ref l_sty), &Constant::Str(ref rs, ref r_sty)) => {
- if l_sty == r_sty {
- Some(ls.cmp(rs))
- } else {
- None
- }
- }
+impl Constant {
+ pub fn partial_cmp(tcx: TyCtxt<'_, '_, '_>, cmp_type: &ty::TyKind<'_>, left: &Self, right: &Self) -> Option<Ordering> {
+ match (left, right) {
+ (&Constant::Str(ref ls), &Constant::Str(ref rs)) => Some(ls.cmp(rs)),
(&Constant::Char(ref l), &Constant::Char(ref r)) => Some(l.cmp(r)),
- (&Constant::Int(l), &Constant::Int(r)) => Some(l.cmp(&r)),
- (&Constant::Float(ref ls, _), &Constant::Float(ref rs, _)) => {
- match (ls.parse::<f64>(), rs.parse::<f64>()) {
- (Ok(ref l), Ok(ref r)) => match (l.partial_cmp(r), l.is_sign_positive() == r.is_sign_positive()) {
- // Check for comparison of -0.0 and 0.0
- (Some(Ordering::Equal), false) => None,
- (x, _) => x
- },
- _ => None,
+ (&Constant::Int(l), &Constant::Int(r)) => {
+ if let ty::Int(int_ty) = *cmp_type {
+ Some(sext(tcx, l, int_ty).cmp(&sext(tcx, r, int_ty)))
+ } else {
+ Some(l.cmp(&r))
}
- }
+ },
+ (&Constant::F64(l), &Constant::F64(r)) => l.partial_cmp(&r),
+ (&Constant::F32(l), &Constant::F32(r)) => l.partial_cmp(&r),
(&Constant::Bool(ref l), &Constant::Bool(ref r)) => Some(l.cmp(r)),
- (&Constant::Tuple(ref l), &Constant::Tuple(ref r)) |
- (&Constant::Vec(ref l), &Constant::Vec(ref r)) => l.partial_cmp(r),
+ (&Constant::Tuple(ref l), &Constant::Tuple(ref r)) | (&Constant::Vec(ref l), &Constant::Vec(ref r)) => l
+ .iter()
+ .zip(r.iter())
+ .map(|(li, ri)| Self::partial_cmp(tcx, cmp_type, li, ri))
+ .find(|r| r.map_or(true, |o| o != Ordering::Equal))
+ .unwrap_or_else(|| Some(l.len().cmp(&r.len()))),
(&Constant::Repeat(ref lv, ref ls), &Constant::Repeat(ref rv, ref rs)) => {
- match lv.partial_cmp(rv) {
+ match Self::partial_cmp(tcx, cmp_type, lv, rv) {
Some(Equal) => Some(ls.cmp(rs)),
x => x,
}
- }
- _ => None, //TODO: Are there any useful inter-type orderings?
+ },
+ _ => None, // TODO: Are there any useful inter-type orderings?
}
}
}
/// parse a `LitKind` to a `Constant`
-#[allow(cast_possible_wrap)]
-pub fn lit_to_constant(lit: &LitKind) -> Constant {
+pub fn lit_to_constant<'tcx>(lit: &LitKind, ty: Ty<'tcx>) -> Constant {
+ use crate::syntax::ast::*;
+
match *lit {
- LitKind::Str(ref is, style) => Constant::Str(is.to_string(), style),
- LitKind::Byte(b) => Constant::Int(ConstInt::U8(b)),
- LitKind::ByteStr(ref s) => Constant::Binary(s.clone()),
+ LitKind::Str(ref is, _) => Constant::Str(is.to_string()),
+ LitKind::Byte(b) => Constant::Int(u128::from(b)),
+ LitKind::ByteStr(ref s) => Constant::Binary(Rc::clone(s)),
LitKind::Char(c) => Constant::Char(c),
- LitKind::Int(value, LitIntType::Unsuffixed) => Constant::Int(ConstInt::Infer(value)),
- LitKind::Int(value, LitIntType::Unsigned(UintTy::U8)) => Constant::Int(ConstInt::U8(value as u8)),
- LitKind::Int(value, LitIntType::Unsigned(UintTy::U16)) => Constant::Int(ConstInt::U16(value as u16)),
- LitKind::Int(value, LitIntType::Unsigned(UintTy::U32)) => Constant::Int(ConstInt::U32(value as u32)),
- LitKind::Int(value, LitIntType::Unsigned(UintTy::U64)) => Constant::Int(ConstInt::U64(value as u64)),
- LitKind::Int(value, LitIntType::Unsigned(UintTy::Us)) => {
- Constant::Int(ConstInt::Usize(ConstUsize::Us32(value as u32)))
- }
- LitKind::Int(value, LitIntType::Signed(IntTy::I8)) => Constant::Int(ConstInt::I8(value as i8)),
- LitKind::Int(value, LitIntType::Signed(IntTy::I16)) => Constant::Int(ConstInt::I16(value as i16)),
- LitKind::Int(value, LitIntType::Signed(IntTy::I32)) => Constant::Int(ConstInt::I32(value as i32)),
- LitKind::Int(value, LitIntType::Signed(IntTy::I64)) => Constant::Int(ConstInt::I64(value as i64)),
- LitKind::Int(value, LitIntType::Signed(IntTy::Is)) => {
- Constant::Int(ConstInt::Isize(ConstIsize::Is32(value as i32)))
- }
- LitKind::Float(ref is, ty) => Constant::Float(is.to_string(), ty.into()),
- LitKind::FloatUnsuffixed(ref is) => Constant::Float(is.to_string(), FloatWidth::Any),
+ LitKind::Int(n, _) => Constant::Int(n),
+ LitKind::Float(ref is, _) |
+ LitKind::FloatUnsuffixed(ref is) => match ty.sty {
+ ty::Float(FloatTy::F32) => Constant::F32(is.as_str().parse().unwrap()),
+ ty::Float(FloatTy::F64) => Constant::F64(is.as_str().parse().unwrap()),
+ _ => bug!(),
+ },
LitKind::Bool(b) => Constant::Bool(b),
}
}
-fn constant_not(o: Constant) -> Option<Constant> {
- use self::Constant::*;
- match o {
- Bool(b) => Some(Bool(!b)),
- Int(value) => (!value).ok().map(Int),
- _ => None,
- }
-}
-
-fn constant_negate(o: Constant) -> Option<Constant> {
- use self::Constant::*;
- match o {
- Int(value) => (-value).ok().map(Int),
- Float(is, ty) => Some(Float(neg_float_str(is), ty)),
- _ => None,
- }
-}
-
-fn neg_float_str(s: String) -> String {
- if s.starts_with('-') {
- s[1..].to_owned()
- } else {
- format!("-{}", s)
- }
-}
-
-pub fn constant(lcx: &LateContext, e: &Expr) -> Option<(Constant, bool)> {
+pub fn constant<'c, 'cc>(lcx: &LateContext<'c, 'cc>, tables: &'c ty::TypeckTables<'cc>, e: &Expr) -> Option<(Constant, bool)> {
let mut cx = ConstEvalLateContext {
- lcx: Some(lcx),
+ tcx: lcx.tcx,
+ tables,
+ param_env: lcx.param_env,
needed_resolution: false,
+ substs: lcx.tcx.intern_substs(&[]),
};
cx.expr(e).map(|cst| (cst, cx.needed_resolution))
}
-pub fn constant_simple(e: &Expr) -> Option<Constant> {
- let mut cx = ConstEvalLateContext {
- lcx: None,
+pub fn constant_simple<'c, 'cc>(lcx: &LateContext<'c, 'cc>, tables: &'c ty::TypeckTables<'cc>, e: &Expr) -> Option<Constant> {
+ constant(lcx, tables, e).and_then(|(cst, res)| if res { None } else { Some(cst) })
+}
+
+/// Creates a `ConstEvalLateContext` from the given `LateContext` and `TypeckTables`
+pub fn constant_context<'c, 'cc>(lcx: &LateContext<'c, 'cc>, tables: &'c ty::TypeckTables<'cc>) -> ConstEvalLateContext<'c, 'cc> {
+ ConstEvalLateContext {
+ tcx: lcx.tcx,
+ tables,
+ param_env: lcx.param_env,
needed_resolution: false,
- };
- cx.expr(e)
+ substs: lcx.tcx.intern_substs(&[]),
+ }
}
-struct ConstEvalLateContext<'c, 'cc: 'c> {
- lcx: Option<&'c LateContext<'c, 'cc>>,
+pub struct ConstEvalLateContext<'a, 'tcx: 'a> {
+ tcx: TyCtxt<'a, 'tcx, 'tcx>,
+ tables: &'a ty::TypeckTables<'tcx>,
+ param_env: ty::ParamEnv<'tcx>,
needed_resolution: bool,
+ substs: &'tcx Substs<'tcx>,
}
impl<'c, 'cc> ConstEvalLateContext<'c, 'cc> {
/// simple constant folding: Insert an expression, get a constant or none.
- fn expr(&mut self, e: &Expr) -> Option<Constant> {
+ pub fn expr(&mut self, e: &Expr) -> Option<Constant> {
match e.node {
- ExprPath(_, _) => self.fetch_path(e),
- ExprBlock(ref block) => self.block(block),
- ExprIf(ref cond, ref then, ref otherwise) => self.ifthenelse(cond, then, otherwise),
- ExprLit(ref lit) => Some(lit_to_constant(&lit.node)),
- ExprArray(ref vec) => self.multi(vec).map(Constant::Vec),
- ExprTup(ref tup) => self.multi(tup).map(Constant::Tuple),
- ExprRepeat(ref value, ref number) => {
- self.binop_apply(value, number, |v, n| Some(Constant::Repeat(Box::new(v), n.as_u64() as usize)))
- }
- ExprUnary(op, ref operand) => {
- self.expr(operand).and_then(|o| {
- match op {
- UnNot => constant_not(o),
- UnNeg => constant_negate(o),
- UnDeref => Some(o),
- }
- })
- }
- ExprBinary(op, ref left, ref right) => self.binop(op, left, right),
+ ExprKind::Path(ref qpath) => self.fetch_path(qpath, e.hir_id),
+ ExprKind::Block(ref block, _) => self.block(block),
+ ExprKind::If(ref cond, ref then, ref otherwise) => self.ifthenelse(cond, then, otherwise),
+ ExprKind::Lit(ref lit) => Some(lit_to_constant(&lit.node, self.tables.expr_ty(e))),
+ ExprKind::Array(ref vec) => self.multi(vec).map(Constant::Vec),
+ ExprKind::Tup(ref tup) => self.multi(tup).map(Constant::Tuple),
+ ExprKind::Repeat(ref value, _) => {
+ let n = match self.tables.expr_ty(e).sty {
+ ty::Array(_, n) => n.assert_usize(self.tcx).expect("array length"),
+ _ => span_bug!(e.span, "typeck error"),
+ };
+ self.expr(value).map(|v| Constant::Repeat(Box::new(v), n))
+ },
+ ExprKind::Unary(op, ref operand) => self.expr(operand).and_then(|o| match op {
+ UnNot => self.constant_not(&o, self.tables.expr_ty(e)),
+ UnNeg => self.constant_negate(&o, self.tables.expr_ty(e)),
+ UnDeref => Some(o),
+ }),
+ ExprKind::Binary(op, ref left, ref right) => self.binop(op, left, right),
// TODO: add other expressions
_ => None,
}
}
+ #[allow(clippy::cast_possible_wrap)]
+ fn constant_not(&self, o: &Constant, ty: ty::Ty<'_>) -> Option<Constant> {
+ use self::Constant::*;
+ match *o {
+ Bool(b) => Some(Bool(!b)),
+ Int(value) => {
+ let value = !value;
+ match ty.sty {
+ ty::Int(ity) => Some(Int(unsext(self.tcx, value as i128, ity))),
+ ty::Uint(ity) => Some(Int(clip(self.tcx, value, ity))),
+ _ => None,
+ }
+ },
+ _ => None,
+ }
+ }
+
+ fn constant_negate(&self, o: &Constant, ty: ty::Ty<'_>) -> Option<Constant> {
+ use self::Constant::*;
+ match *o {
+ Int(value) => {
+ let ity = match ty.sty {
+ ty::Int(ity) => ity,
+ _ => return None,
+ };
+ // sign extend
+ let value = sext(self.tcx, value, ity);
+ let value = value.checked_neg()?;
+ // clear unused bits
+ Some(Int(unsext(self.tcx, value, ity)))
+ },
+ F32(f) => Some(F32(-f)),
+ F64(f) => Some(F64(-f)),
+ _ => None,
+ }
+ }
+
/// create `Some(Vec![..])` of all constants, unless there is any
/// non-constant part
- fn multi<E: Deref<Target = Expr> + Sized>(&mut self, vec: &[E]) -> Option<Vec<Constant>> {
+ fn multi(&mut self, vec: &[Expr]) -> Option<Vec<Constant>> {
vec.iter()
- .map(|elem| self.expr(elem))
- .collect::<Option<_>>()
+ .map(|elem| self.expr(elem))
+ .collect::<Option<_>>()
}
- /// lookup a possibly constant expression from a ExprPath
- fn fetch_path(&mut self, e: &Expr) -> Option<Constant> {
- if let Some(lcx) = self.lcx {
- let mut maybe_id = None;
- if let Some(&PathResolution { base_def: Def::Const(id), .. }) = lcx.tcx.def_map.borrow().get(&e.id) {
- maybe_id = Some(id);
- }
- // separate if lets to avoid double borrowing the def_map
- if let Some(id) = maybe_id {
- if let Some((const_expr, _ty)) = lookup_const_by_id(lcx.tcx, id, None) {
- let ret = self.expr(const_expr);
- if ret.is_some() {
- self.needed_resolution = true;
- }
- return ret;
+ /// lookup a possibly constant expression from a ExprKind::Path
+ fn fetch_path(&mut self, qpath: &QPath, id: HirId) -> Option<Constant> {
+ use crate::rustc::mir::interpret::GlobalId;
+
+ let def = self.tables.qpath_def(qpath, id);
+ match def {
+ Def::Const(def_id) | Def::AssociatedConst(def_id) => {
+ let substs = self.tables.node_substs(id);
+ let substs = if self.substs.is_empty() {
+ substs
+ } else {
+ substs.subst(self.tcx, self.substs)
+ };
+ let instance = Instance::resolve(self.tcx, self.param_env, def_id, substs)?;
+ let gid = GlobalId {
+ instance,
+ promoted: None,
+ };
+
+ let result = self.tcx.const_eval(self.param_env.and(gid)).ok()?;
+ let ret = miri_to_const(self.tcx, result);
+ if ret.is_some() {
+ self.needed_resolution = true;
}
- }
+ return ret;
+ },
+ _ => {},
}
None
}
}
}
- fn ifthenelse(&mut self, cond: &Expr, then: &
Block, otherwise: &Option<P<Expr>>) -> Option<Constant> {
+ fn ifthenelse(&mut self, cond: &Expr, then: &
P<Expr>, otherwise: &Option<P<Expr>>) -> Option<Constant> {
if let Some(Constant::Bool(b)) = self.expr(cond) {
if b {
- self.block(then)
+ self.expr(&**then)
} else {
otherwise.as_ref().and_then(|expr| self.expr(expr))
}
}
fn binop(&mut self, op: BinOp, left: &Expr, right: &Expr) -> Option<Constant> {
- let l = if let Some(l) = self.expr(left) {
- l
- } else {
- return None;
- };
+ let l = self.expr(left)?;
let r = self.expr(right);
- match (op.node, l, r) {
- (BiAdd, Constant::Int(l), Some(Constant::Int(r))) => (l + r).ok().map(Constant::Int),
- (BiSub, Constant::Int(l), Some(Constant::Int(r))) => (l - r).ok().map(Constant::Int),
- (BiMul, Constant::Int(l), Some(Constant::Int(r))) => (l * r).ok().map(Constant::Int),
- (BiDiv, Constant::Int(l), Some(Constant::Int(r))) => (l / r).ok().map(Constant::Int),
- (BiRem, Constant::Int(l), Some(Constant::Int(r))) => (l % r).ok().map(Constant::Int),
- (BiAnd, Constant::Bool(false), _) => Some(Constant::Bool(false)),
- (BiOr, Constant::Bool(true), _) => Some(Constant::Bool(true)),
- (BiAnd, Constant::Bool(true), Some(r)) |
- (BiOr, Constant::Bool(false), Some(r)) => Some(r),
- (BiBitXor, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l ^ r)),
- (BiBitXor, Constant::Int(l), Some(Constant::Int(r))) => (l ^ r).ok().map(Constant::Int),
- (BiBitAnd, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l & r)),
- (BiBitAnd, Constant::Int(l), Some(Constant::Int(r))) => (l & r).ok().map(Constant::Int),
- (BiBitOr, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l | r)),
- (BiBitOr, Constant::Int(l), Some(Constant::Int(r))) => (l | r).ok().map(Constant::Int),
- (BiShl, Constant::Int(l), Some(Constant::Int(r))) => (l << r).ok().map(Constant::Int),
- (BiShr, Constant::Int(l), Some(Constant::Int(r))) => (l >> r).ok().map(Constant::Int),
- (BiEq, Constant::Int(l), Some(Constant::Int(r))) => Some(Constant::Bool(l == r)),
- (BiNe, Constant::Int(l), Some(Constant::Int(r))) => Some(Constant::Bool(l != r)),
- (BiLt, Constant::Int(l), Some(Constant::Int(r))) => Some(Constant::Bool(l < r)),
- (BiLe, Constant::Int(l), Some(Constant::Int(r))) => Some(Constant::Bool(l <= r)),
- (BiGe, Constant::Int(l), Some(Constant::Int(r))) => Some(Constant::Bool(l >= r)),
- (BiGt, Constant::Int(l), Some(Constant::Int(r))) => Some(Constant::Bool(l > r)),
- _ => None,
+ match (l, r) {
+ (Constant::Int(l), Some(Constant::Int(r))) => {
+ match self.tables.expr_ty(left).sty {
+ ty::Int(ity) => {
+ let l = sext(self.tcx, l, ity);
+ let r = sext(self.tcx, r, ity);
+ let zext = |n: i128| Constant::Int(unsext(self.tcx, n, ity));
+ match op.node {
+ BinOpKind::Add => l.checked_add(r).map(zext),
+ BinOpKind::Sub => l.checked_sub(r).map(zext),
+ BinOpKind::Mul => l.checked_mul(r).map(zext),
+ BinOpKind::Div if r != 0 => l.checked_div(r).map(zext),
+ BinOpKind::Rem if r != 0 => l.checked_rem(r).map(zext),
+ BinOpKind::Shr => l.checked_shr(
+ r.try_into().expect("invalid shift")
+ ).map(zext),
+ BinOpKind::Shl => l.checked_shl(
+ r.try_into().expect("invalid shift")
+ ).map(zext),
+ BinOpKind::BitXor => Some(zext(l ^ r)),
+ BinOpKind::BitOr => Some(zext(l | r)),
+ BinOpKind::BitAnd => Some(zext(l & r)),
+ BinOpKind::Eq => Some(Constant::Bool(l == r)),
+ BinOpKind::Ne => Some(Constant::Bool(l != r)),
+ BinOpKind::Lt => Some(Constant::Bool(l < r)),
+ BinOpKind::Le => Some(Constant::Bool(l <= r)),
+ BinOpKind::Ge => Some(Constant::Bool(l >= r)),
+ BinOpKind::Gt => Some(Constant::Bool(l > r)),
+ _ => None,
+ }
+ }
+ ty::Uint(_) => {
+ match op.node {
+ BinOpKind::Add => l.checked_add(r).map(Constant::Int),
+ BinOpKind::Sub => l.checked_sub(r).map(Constant::Int),
+ BinOpKind::Mul => l.checked_mul(r).map(Constant::Int),
+ BinOpKind::Div => l.checked_div(r).map(Constant::Int),
+ BinOpKind::Rem => l.checked_rem(r).map(Constant::Int),
+ BinOpKind::Shr => l.checked_shr(
+ r.try_into().expect("shift too large")
+ ).map(Constant::Int),
+ BinOpKind::Shl => l.checked_shl(
+ r.try_into().expect("shift too large")
+ ).map(Constant::Int),
+ BinOpKind::BitXor => Some(Constant::Int(l ^ r)),
+ BinOpKind::BitOr => Some(Constant::Int(l | r)),
+ BinOpKind::BitAnd => Some(Constant::Int(l & r)),
+ BinOpKind::Eq => Some(Constant::Bool(l == r)),
+ BinOpKind::Ne => Some(Constant::Bool(l != r)),
+ BinOpKind::Lt => Some(Constant::Bool(l < r)),
+ BinOpKind::Le => Some(Constant::Bool(l <= r)),
+ BinOpKind::Ge => Some(Constant::Bool(l >= r)),
+ BinOpKind::Gt => Some(Constant::Bool(l > r)),
+ _ => None,
+ }
+ },
+ _ => None,
+ }
+ },
+ (Constant::F32(l), Some(Constant::F32(r))) => match op.node {
+ BinOpKind::Add => Some(Constant::F32(l + r)),
+ BinOpKind::Sub => Some(Constant::F32(l - r)),
+ BinOpKind::Mul => Some(Constant::F32(l * r)),
+ BinOpKind::Div => Some(Constant::F32(l / r)),
+ BinOpKind::Rem => Some(Constant::F32(l % r)),
+ BinOpKind::Eq => Some(Constant::Bool(l == r)),
+ BinOpKind::Ne => Some(Constant::Bool(l != r)),
+ BinOpKind::Lt => Some(Constant::Bool(l < r)),
+ BinOpKind::Le => Some(Constant::Bool(l <= r)),
+ BinOpKind::Ge => Some(Constant::Bool(l >= r)),
+ BinOpKind::Gt => Some(Constant::Bool(l > r)),
+ _ => None,
+ },
+ (Constant::F64(l), Some(Constant::F64(r))) => match op.node {
+ BinOpKind::Add => Some(Constant::F64(l + r)),
+ BinOpKind::Sub => Some(Constant::F64(l - r)),
+ BinOpKind::Mul => Some(Constant::F64(l * r)),
+ BinOpKind::Div => Some(Constant::F64(l / r)),
+ BinOpKind::Rem => Some(Constant::F64(l % r)),
+ BinOpKind::Eq => Some(Constant::Bool(l == r)),
+ BinOpKind::Ne => Some(Constant::Bool(l != r)),
+ BinOpKind::Lt => Some(Constant::Bool(l < r)),
+ BinOpKind::Le => Some(Constant::Bool(l <= r)),
+ BinOpKind::Ge => Some(Constant::Bool(l >= r)),
+ BinOpKind::Gt => Some(Constant::Bool(l > r)),
+ _ => None,
+ },
+ (l, r) => match (op.node, l, r) {
+ (BinOpKind::And, Constant::Bool(false), _) => Some(Constant::Bool(false)),
+ (BinOpKind::Or, Constant::Bool(true), _) => Some(Constant::Bool(true)),
+ (BinOpKind::And, Constant::Bool(true), Some(r)) | (BinOpKind::Or, Constant::Bool(false), Some(r)) => Some(r),
+ (BinOpKind::BitXor, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l ^ r)),
+ (BinOpKind::BitAnd, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l & r)),
+ (BinOpKind::BitOr, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l | r)),
+ _ => None,
+ },
}
}
+}
-
- fn binop_apply<F>(&mut self, left: &Expr, right: &Expr, op: F) -> Option<Constant>
- where F: Fn(Constant, Constant) -> Option<Constant>
- {
- if let (Some(lc), Some(rc)) = (self.expr(left), self.expr(right)) {
- op(lc, rc)
- } else {
- None
+pub fn miri_to_const<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, result: &ty::Const<'tcx>) -> Option<Constant> {
+ use crate::rustc::mir::interpret::{Scalar, ConstValue};
+ match result.val {
+ ConstValue::Scalar(Scalar::Bits{ bits: b, ..}) => match result.ty.sty {
+ ty::Bool => Some(Constant::Bool(b == 1)),
+ ty::Uint(_) | ty::Int(_) => Some(Constant::Int(b)),
+ ty::Float(FloatTy::F32) => Some(Constant::F32(f32::from_bits(
+ b.try_into().expect("invalid f32 bit representation")
+ ))),
+ ty::Float(FloatTy::F64) => Some(Constant::F64(f64::from_bits(
+ b.try_into().expect("invalid f64 bit representation")
+ ))),
+ // FIXME: implement other conversion
+ _ => None,
+ },
+ ConstValue::ScalarPair(Scalar::Ptr(ptr),
+ Scalar::Bits { bits: n, .. }) => match result.ty.sty {
+ ty::Ref(_, tam, _) => match tam.sty {
+ ty::Str => {
+ let alloc = tcx
+ .alloc_map
+ .lock()
+ .unwrap_memory(ptr.alloc_id);
+ let offset = ptr.offset.bytes().try_into().expect("too-large pointer offset");
+ let n = n as usize;
+ String::from_utf8(alloc.bytes[offset..(offset + n)].to_owned()).ok().map(Constant::Str)
+ },
+ _ => None,
+ },
+ _ => None,
}
+ // FIXME: implement other conversions
+ _ => None,
}
}
projects / rust.git / blobdiff