From: Ralf Jung Date: Fri, 28 Feb 2020 10:04:12 +0000 (+0100) Subject: remove ScalarMaybeUndef::to_bits and make Scalar::to_bits private X-Git-Url: https://git.lizzy.rs/?a=commitdiff_plain;h=63c77f1bd0beee9c3ee75cc41c507e31d3a72a5d;p=rust.git remove ScalarMaybeUndef::to_bits and make Scalar::to_bits private --- diff --git a/src/librustc/mir/interpret/value.rs b/src/librustc/mir/interpret/value.rs index 2eb5f7ca878..c931fcf71e3 100644 --- a/src/librustc/mir/interpret/value.rs +++ b/src/librustc/mir/interpret/value.rs @@ -382,9 +382,10 @@ pub fn to_bits_or_ptr( } } - /// Do not call this method! Use either `assert_bits` or `force_bits`. + /// This method is intentionally private! + /// It is just a helper for other methods in this file. #[inline] - pub fn to_bits(self, target_size: Size) -> InterpResult<'tcx, u128> { + fn to_bits(self, target_size: Size) -> InterpResult<'tcx, u128> { match self { Scalar::Raw { data, size } => { assert_eq!(target_size.bytes(), size as u64); @@ -405,7 +406,7 @@ pub fn assert_bits(self, target_size: Size) -> u128 { pub fn assert_ptr(self) -> Pointer { match self { Scalar::Ptr(p) => p, - Scalar::Raw { .. } => bug!("expected a Pointer but got Raw bits") + Scalar::Raw { .. } => bug!("expected a Pointer but got Raw bits"), } } @@ -586,12 +587,6 @@ pub fn not_undef(self) -> InterpResult<'static, Scalar> { } } - /// Do not call this method! Use either `assert_bits` or `force_bits`. - #[inline(always)] - pub fn to_bits(self, target_size: Size) -> InterpResult<'tcx, u128> { - self.not_undef()?.to_bits(target_size) - } - #[inline(always)] pub fn to_bool(self) -> InterpResult<'tcx, bool> { self.not_undef()?.to_bool() diff --git a/src/librustc/ty/sty.rs b/src/librustc/ty/sty.rs index c3698f402a9..241781bb93d 100644 --- a/src/librustc/ty/sty.rs +++ b/src/librustc/ty/sty.rs @@ -2576,7 +2576,7 @@ pub fn try_to_scalar(&self) -> Option { #[inline] pub fn try_to_bits(&self, size: ty::layout::Size) -> Option { - self.try_to_scalar()?.to_bits(size).ok() + if let ConstKind::Value(val) = self { val.try_to_bits(size) } else { None } } } diff --git a/src/librustc_mir/interpret/intrinsics.rs b/src/librustc_mir/interpret/intrinsics.rs index cd06cf01bfa..d63abdc3562 100644 --- a/src/librustc_mir/interpret/intrinsics.rs +++ b/src/librustc_mir/interpret/intrinsics.rs @@ -384,7 +384,7 @@ pub fn exact_div( // `x % y != 0` or `y == 0` or `x == T::min_value() && y == -1`. // First, check x % y != 0 (or if that computation overflows). let (res, overflow, _ty) = self.overflowing_binary_op(BinOp::Rem, a, b)?; - if overflow || res.to_bits(a.layout.size)? != 0 { + if overflow || res.assert_bits(a.layout.size) != 0 { // Then, check if `b` is -1, which is the "min_value / -1" case. let minus1 = Scalar::from_int(-1, dest.layout.size); let b_scalar = b.to_scalar().unwrap(); diff --git a/src/librustc_mir/interpret/operand.rs b/src/librustc_mir/interpret/operand.rs index 14b8a341e26..20efe7dfc03 100644 --- a/src/librustc_mir/interpret/operand.rs +++ b/src/librustc_mir/interpret/operand.rs @@ -96,40 +96,40 @@ pub struct ImmTy<'tcx, Tag = ()> { impl std::fmt::Display for ImmTy<'tcx, Tag> { fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { match &self.imm { - Immediate::Scalar(ScalarMaybeUndef::Scalar(s)) => match s.to_bits(self.layout.size) { - Ok(s) => { - match self.layout.ty.kind { - ty::Int(_) => { - return write!( - fmt, - "{}", - super::sign_extend(s, self.layout.size) as i128, - ); - } - ty::Uint(_) => return write!(fmt, "{}", s), - ty::Bool if s == 0 => return fmt.write_str("false"), - ty::Bool if s == 1 => return fmt.write_str("true"), - ty::Char => { - if let Some(c) = u32::try_from(s).ok().and_then(std::char::from_u32) { - return write!(fmt, "{}", c); - } + // We cannot use `to_bits_or_ptr` as we do not have a `tcx`. + // So we use `is_bits` and circumvent a bunch of sanity checking -- but + // this is anyway only for printing. + Immediate::Scalar(ScalarMaybeUndef::Scalar(s)) if s.is_ptr() => { + fmt.write_str("{pointer}") + } + Immediate::Scalar(ScalarMaybeUndef::Scalar(s)) => { + let s = s.assert_bits(self.layout.size); + match self.layout.ty.kind { + ty::Int(_) => { + return write!(fmt, "{}", super::sign_extend(s, self.layout.size) as i128,); + } + ty::Uint(_) => return write!(fmt, "{}", s), + ty::Bool if s == 0 => return fmt.write_str("false"), + ty::Bool if s == 1 => return fmt.write_str("true"), + ty::Char => { + if let Some(c) = u32::try_from(s).ok().and_then(std::char::from_u32) { + return write!(fmt, "{}", c); } - ty::Float(ast::FloatTy::F32) => { - if let Ok(u) = u32::try_from(s) { - return write!(fmt, "{}", f32::from_bits(u)); - } + } + ty::Float(ast::FloatTy::F32) => { + if let Ok(u) = u32::try_from(s) { + return write!(fmt, "{}", f32::from_bits(u)); } - ty::Float(ast::FloatTy::F64) => { - if let Ok(u) = u64::try_from(s) { - return write!(fmt, "{}", f64::from_bits(u)); - } + } + ty::Float(ast::FloatTy::F64) => { + if let Ok(u) = u64::try_from(s) { + return write!(fmt, "{}", f64::from_bits(u)); } - _ => {} } - write!(fmt, "{:x}", s) + _ => {} } - Err(_) => fmt.write_str("{pointer}"), - }, + write!(fmt, "{:x}", s) + } Immediate::Scalar(ScalarMaybeUndef::Undef) => fmt.write_str("{undef}"), Immediate::ScalarPair(..) => fmt.write_str("{wide pointer or tuple}"), } @@ -205,11 +205,6 @@ pub fn try_from_int(i: impl Into, layout: TyLayout<'tcx>) -> Option pub fn from_int(i: impl Into, layout: TyLayout<'tcx>) -> Self { Self::from_scalar(Scalar::from_int(i, layout.size), layout) } - - #[inline] - pub fn to_bits(self) -> InterpResult<'tcx, u128> { - self.to_scalar()?.to_bits(self.layout.size) - } } // Use the existing layout if given (but sanity check in debug mode), diff --git a/src/librustc_mir/interpret/validity.rs b/src/librustc_mir/interpret/validity.rs index aa2b3040a71..48c0e7930e9 100644 --- a/src/librustc_mir/interpret/validity.rs +++ b/src/librustc_mir/interpret/validity.rs @@ -361,16 +361,17 @@ fn visit_primitive(&mut self, value: OpTy<'tcx, M::PointerTag>) -> InterpResult< ty::Float(_) | ty::Int(_) | ty::Uint(_) => { // NOTE: Keep this in sync with the array optimization for int/float // types below! - let size = value.layout.size; let value = value.to_scalar_or_undef(); if self.ref_tracking_for_consts.is_some() { // Integers/floats in CTFE: Must be scalar bits, pointers are dangerous - try_validation!( - value.to_bits(size), - value, - self.path, - "initialized plain (non-pointer) bytes" - ); + let is_bits = value.not_undef().map_or(false, |v| v.is_bits()); + if !is_bits { + throw_validation_failure!( + value, + self.path, + "initialized plain (non-pointer) bytes" + ) + } } else { // At run-time, for now, we accept *anything* for these types, including // undef. We should fix that, but let's start low. diff --git a/src/librustc_mir/transform/const_prop.rs b/src/librustc_mir/transform/const_prop.rs index 9e05133132e..fe736321df7 100644 --- a/src/librustc_mir/transform/const_prop.rs +++ b/src/librustc_mir/transform/const_prop.rs @@ -557,7 +557,9 @@ fn check_binary_op( let left_ty = left.ty(&self.local_decls, self.tcx); let left_size_bits = self.ecx.layout_of(left_ty).ok()?.size.bits(); let right_size = r.layout.size; - let r_bits = r.to_scalar().and_then(|r| r.to_bits(right_size)); + let r_bits = r.to_scalar().ok(); + // This is basically `force_bits`. + let r_bits = r_bits.and_then(|r| r.to_bits_or_ptr(right_size, &self.tcx).ok()); if r_bits.map_or(false, |b| b >= left_size_bits as u128) { self.report_assert_as_lint( lint::builtin::ARITHMETIC_OVERFLOW,