Scalar: only convert to/from soft-float types, not to/from hard-floats

[rust.git] / src / librustc / mir / interpret / value.rs

diff --git a/src/librustc/mir/interpret/value.rs b/src/librustc/mir/interpret/value.rs
index 454a4e2111a9cfb8d5ca41ef77e3c927cdaba551..1909f3cb998be90584d99480dd7c2e837ed6fd06 100644 (file)
--- a/src/librustc/mir/interpret/value.rs
+++ b/src/librustc/mir/interpret/value.rs
@@ -1,5 +1,6 @@
 use std::fmt;
 use rustc_macros::HashStable;
+use rustc_apfloat::{Float, ieee::{Double, Single}};
 
 use crate::ty::{Ty, InferConst, ParamConst, layout::{HasDataLayout, Size}, subst::SubstsRef};
 use crate::ty::PlaceholderConst;
@@ -292,12 +293,12 @@ pub fn from_int(i: impl Into<i128>, size: Size) -> Self {
     }
 
     #[inline]
-    pub fn from_f32(f: f32) -> Self {
+    pub fn from_f32(f: Single) -> Self {
         Scalar::Raw { data: f.to_bits() as u128, size: 4 }
     }
 
     #[inline]
-    pub fn from_f64(f: f64) -> Self {
+    pub fn from_f64(f: Double) -> Self {
         Scalar::Raw { data: f.to_bits() as u128, size: 8 }
     }
 
@@ -427,13 +428,15 @@ pub fn to_isize(self, cx: &impl HasDataLayout) -> InterpResult<'static, i64> {
     }
 
     #[inline]
-    pub fn to_f32(self) -> InterpResult<'static, f32> {
-        Ok(f32::from_bits(self.to_u32()?))
+    pub fn to_f32(self) -> InterpResult<'static, Single> {
+        // Going through `u32` to check size and truncation.
+        Ok(Single::from_bits(self.to_u32()? as u128))
     }
 
     #[inline]
-    pub fn to_f64(self) -> InterpResult<'static, f64> {
-        Ok(f64::from_bits(self.to_u64()?))
+    pub fn to_f64(self) -> InterpResult<'static, Double> {
+        // Going through `u64` to check size and truncation.
+        Ok(Double::from_bits(self.to_u64()? as u128))
     }
 }
 
@@ -517,12 +520,12 @@ pub fn to_char(self) -> InterpResult<'tcx, char> {
     }
 
     #[inline(always)]
-    pub fn to_f32(self) -> InterpResult<'tcx, f32> {
+    pub fn to_f32(self) -> InterpResult<'tcx, Single> {
         self.not_undef()?.to_f32()
     }
 
     #[inline(always)]
-    pub fn to_f64(self) -> InterpResult<'tcx, f64> {
+    pub fn to_f64(self) -> InterpResult<'tcx, Double> {
         self.not_undef()?.to_f64()
     }