Merge ref 'b733736ea2fe' from rust-lang/rust

Pull recent changes from https://github.com/rust-lang/rust via Josh.

Upstream ref: b733736ea2feb7798c99cbb9a769bce74be108df
Filtered ref: 62d76e7
Upstream diff: rust-lang/rust@f6092f2...b733736

This merge was created using https://github.com/rust-lang/josh-sync.

Author: The Miri Cronjob Bot

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"

src/machine.rs

@@ -1293,6 +1293,11 @@ impl<'tcx> Machine<'tcx> for MiriMachine<'tcx> {
         ecx.equal_float_min_max(a, b)
     }
 
+    #[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())

tests/pass/vec.rs

@@ -169,6 +169,15 @@ fn miri_issue_2759() {
     input.replace_range(0..0, "0");
 }
 
+/// This was skirting the edge of UB, let's make sure it remains on the sound side.
+/// Context: <https://github.com/rust-lang/rust/pull/141032>.
+fn extract_if() {
+    let mut v = vec![Box::new(0u64), Box::new(1u64)];
+    for item in v.extract_if(.., |x| **x == 0) {
+        drop(item);
+    }
+}
+
 fn main() {
     assert_eq!(vec_reallocate().len(), 5);
 
@@ -199,4 +208,5 @@ fn main() {
     swap_remove();
     reverse();
     miri_issue_2759();
+    extract_if();
 }