Rollup merge of #146735 - Qelxiros:const_mul_add, r=tgross35,RalfJung

unstably constify float mul_add methods

Tracking issue: rust-lang/rust#146724
r? `@tgross35`

2 files changed, 5 insertions, 41 deletions

diff --git a/src/tools/miri/src/intrinsics/math.rs b/src/tools/miri/src/intrinsics/math.rs
index b9c99f28594..0cc4342f0d5 100644
--- a/src/tools/miri/src/intrinsics/math.rs
+++ b/src/tools/miri/src/intrinsics/math.rs
@@ -1,4 +1,3 @@
-use rand::Rng;
 use rustc_apfloat::{self, Float, FloatConvert, Round};
 use rustc_middle::mir;
 use rustc_middle::ty::{self, FloatTy};
@@ -39,46 +38,6 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             "sqrtf64" => sqrt::<rustc_apfloat::ieee::Double>(this, args, dest)?,
             "sqrtf128" => sqrt::<rustc_apfloat::ieee::Quad>(this, args, dest)?,
 
-            "fmaf32" => {
-                let [a, b, c] = check_intrinsic_arg_count(args)?;
-                let a = this.read_scalar(a)?.to_f32()?;
-                let b = this.read_scalar(b)?.to_f32()?;
-                let c = this.read_scalar(c)?.to_f32()?;
-                let res = a.mul_add(b, c).value;
-                let res = this.adjust_nan(res, &[a, b, c]);
-                this.write_scalar(res, dest)?;
-            }
-            "fmaf64" => {
-                let [a, b, c] = check_intrinsic_arg_count(args)?;
-                let a = this.read_scalar(a)?.to_f64()?;
-                let b = this.read_scalar(b)?.to_f64()?;
-                let c = this.read_scalar(c)?.to_f64()?;
-                let res = a.mul_add(b, c).value;
-                let res = this.adjust_nan(res, &[a, b, c]);
-                this.write_scalar(res, dest)?;
-            }
-
-            "fmuladdf32" => {
-                let [a, b, c] = check_intrinsic_arg_count(args)?;
-                let a = this.read_scalar(a)?.to_f32()?;
-                let b = this.read_scalar(b)?.to_f32()?;
-                let c = this.read_scalar(c)?.to_f32()?;
-                let fuse: bool = this.machine.float_nondet && this.machine.rng.get_mut().random();
-                let res = if fuse { a.mul_add(b, c).value } else { ((a * b).value + c).value };
-                let res = this.adjust_nan(res, &[a, b, c]);
-                this.write_scalar(res, dest)?;
-            }
-            "fmuladdf64" => {
-                let [a, b, c] = check_intrinsic_arg_count(args)?;
-                let a = this.read_scalar(a)?.to_f64()?;
-                let b = this.read_scalar(b)?.to_f64()?;
-                let c = this.read_scalar(c)?.to_f64()?;
-                let fuse: bool = this.machine.float_nondet && this.machine.rng.get_mut().random();
-                let res = if fuse { a.mul_add(b, c).value } else { ((a * b).value + c).value };
-                let res = this.adjust_nan(res, &[a, b, c]);
-                this.write_scalar(res, dest)?;
-            }
-
             #[rustfmt::skip]
             | "fadd_fast"
             | "fsub_fast"
diff --git a/src/tools/miri/src/machine.rs b/src/tools/miri/src/machine.rs
index 04c8bee72c0..d307636e782 100644
--- a/src/tools/miri/src/machine.rs
+++ b/src/tools/miri/src/machine.rs
@@ -1294,6 +1294,11 @@ impl<'tcx> Machine<'tcx> for MiriMachine<'tcx> {
     }
 
     #[inline(always)]
+    fn float_fuse_mul_add(ecx: &mut InterpCx<'tcx, Self>) -> bool {
+        ecx.machine.float_nondet && ecx.machine.rng.get_mut().random()
+    }
+
+    #[inline(always)]
     fn ub_checks(ecx: &InterpCx<'tcx, Self>) -> InterpResult<'tcx, bool> {
         interp_ok(ecx.tcx.sess.ub_checks())
     }