Move unary_op_* functions from shims::x86::sse module to shims::x86

rust-lang · Dec 7, 2023 · c37f4d6 · c37f4d6
1 parent f7af14b
commit c37f4d6
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Showing 2 changed files with 129 additions and 125 deletions.
diff --git a/src/tools/miri/src/shims/x86/mod.rs b/src/tools/miri/src/shims/x86/mod.rs
@@ -1,3 +1,6 @@
+use rand::Rng as _;
+
+use rustc_apfloat::{ieee::Single, Float as _};
 use rustc_middle::{mir, ty};
 use rustc_span::Symbol;
 use rustc_target::abi::Size;
@@ -331,6 +334,127 @@ fn bin_op_simd_float_all<'tcx, F: rustc_apfloat::Float>(
     Ok(())
 }
 
+#[derive(Copy, Clone)]
+enum FloatUnaryOp {
+    /// sqrt(x)
+    ///
+    /// <https://www.felixcloutier.com/x86/sqrtss>
+    /// <https://www.felixcloutier.com/x86/sqrtps>
+    Sqrt,
+    /// Approximation of 1/x
+    ///
+    /// <https://www.felixcloutier.com/x86/rcpss>
+    /// <https://www.felixcloutier.com/x86/rcpps>
+    Rcp,
+    /// Approximation of 1/sqrt(x)
+    ///
+    /// <https://www.felixcloutier.com/x86/rsqrtss>
+    /// <https://www.felixcloutier.com/x86/rsqrtps>
+    Rsqrt,
+}
+
+/// Performs `which` scalar operation on `op` and returns the result.
+#[allow(clippy::arithmetic_side_effects)] // floating point operations without side effects
+fn unary_op_f32<'tcx>(
+    this: &mut crate::MiriInterpCx<'_, 'tcx>,
+    which: FloatUnaryOp,
+    op: &ImmTy<'tcx, Provenance>,
+) -> InterpResult<'tcx, Scalar<Provenance>> {
+    match which {
+        FloatUnaryOp::Sqrt => {
+            let op = op.to_scalar();
+            // FIXME using host floats
+            Ok(Scalar::from_u32(f32::from_bits(op.to_u32()?).sqrt().to_bits()))
+        }
+        FloatUnaryOp::Rcp => {
+            let op = op.to_scalar().to_f32()?;
+            let div = (Single::from_u128(1).value / op).value;
+            // Apply a relative error with a magnitude on the order of 2^-12 to simulate the
+            // inaccuracy of RCP.
+            let res = apply_random_float_error(this, div, -12);
+            Ok(Scalar::from_f32(res))
+        }
+        FloatUnaryOp::Rsqrt => {
+            let op = op.to_scalar().to_u32()?;
+            // FIXME using host floats
+            let sqrt = Single::from_bits(f32::from_bits(op).sqrt().to_bits().into());
+            let rsqrt = (Single::from_u128(1).value / sqrt).value;
+            // Apply a relative error with a magnitude on the order of 2^-12 to simulate the
+            // inaccuracy of RSQRT.
+            let res = apply_random_float_error(this, rsqrt, -12);
+            Ok(Scalar::from_f32(res))
+        }
+    }
+}
+
+/// Disturbes a floating-point result by a relative error on the order of (-2^scale, 2^scale).
+#[allow(clippy::arithmetic_side_effects)] // floating point arithmetic cannot panic
+fn apply_random_float_error<F: rustc_apfloat::Float>(
+    this: &mut crate::MiriInterpCx<'_, '_>,
+    val: F,
+    err_scale: i32,
+) -> F {
+    let rng = this.machine.rng.get_mut();
+    // generates rand(0, 2^64) * 2^(scale - 64) = rand(0, 1) * 2^scale
+    let err =
+        F::from_u128(rng.gen::<u64>().into()).value.scalbn(err_scale.checked_sub(64).unwrap());
+    // give it a random sign
+    let err = if rng.gen::<bool>() { -err } else { err };
+    // multiple the value with (1+err)
+    (val * (F::from_u128(1).value + err).value).value
+}
+
+/// Performs `which` operation on the first component of `op` and copies
+/// the other components. The result is stored in `dest`.
+fn unary_op_ss<'tcx>(
+    this: &mut crate::MiriInterpCx<'_, 'tcx>,
+    which: FloatUnaryOp,
+    op: &OpTy<'tcx, Provenance>,
+    dest: &PlaceTy<'tcx, Provenance>,
+) -> InterpResult<'tcx, ()> {
+    let (op, op_len) = this.operand_to_simd(op)?;
+    let (dest, dest_len) = this.place_to_simd(dest)?;
+
+    assert_eq!(dest_len, op_len);
+
+    let res0 = unary_op_f32(this, which, &this.read_immediate(&this.project_index(&op, 0)?)?)?;
+    this.write_scalar(res0, &this.project_index(&dest, 0)?)?;
+
+    for i in 1..dest_len {
+        this.copy_op(
+            &this.project_index(&op, i)?,
+            &this.project_index(&dest, i)?,
+            /*allow_transmute*/ false,
+        )?;
+    }
+
+    Ok(())
+}
+
+/// Performs `which` operation on each component of `op`, storing the
+/// result is stored in `dest`.
+fn unary_op_ps<'tcx>(
+    this: &mut crate::MiriInterpCx<'_, 'tcx>,
+    which: FloatUnaryOp,
+    op: &OpTy<'tcx, Provenance>,
+    dest: &PlaceTy<'tcx, Provenance>,
+) -> InterpResult<'tcx, ()> {
+    let (op, op_len) = this.operand_to_simd(op)?;
+    let (dest, dest_len) = this.place_to_simd(dest)?;
+
+    assert_eq!(dest_len, op_len);
+
+    for i in 0..dest_len {
+        let op = this.read_immediate(&this.project_index(&op, i)?)?;
+        let dest = this.project_index(&dest, i)?;
+
+        let res = unary_op_f32(this, which, &op)?;
+        this.write_scalar(res, &dest)?;
+    }
+
+    Ok(())
+}
+
 /// Converts each element of `op` from floating point to signed integer.
 ///
 /// When the input value is NaN or out of range, fall back to minimum value.

diff --git a/src/tools/miri/src/shims/x86/sse.rs b/src/tools/miri/src/shims/x86/sse.rs
@@ -1,11 +1,12 @@
-use rustc_apfloat::{ieee::Single, Float as _};
+use rustc_apfloat::ieee::Single;
 use rustc_middle::mir;
 use rustc_span::Symbol;
 use rustc_target::spec::abi::Abi;
 
-use rand::Rng as _;
-
-use super::{bin_op_simd_float_all, bin_op_simd_float_first, FloatBinOp};
+use super::{
+    bin_op_simd_float_all, bin_op_simd_float_first, unary_op_ps, unary_op_ss, FloatBinOp,
+    FloatUnaryOp,
+};
 use crate::*;
 use shims::foreign_items::EmulateForeignItemResult;
 
@@ -219,124 +220,3 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
         Ok(EmulateForeignItemResult::NeedsJumping)
     }
 }
-
-#[derive(Copy, Clone)]
-enum FloatUnaryOp {
-    /// sqrt(x)
-    ///
-    /// <https://www.felixcloutier.com/x86/sqrtss>
-    /// <https://www.felixcloutier.com/x86/sqrtps>
-    Sqrt,
-    /// Approximation of 1/x
-    ///
-    /// <https://www.felixcloutier.com/x86/rcpss>
-    /// <https://www.felixcloutier.com/x86/rcpps>
-    Rcp,
-    /// Approximation of 1/sqrt(x)
-    ///
-    /// <https://www.felixcloutier.com/x86/rsqrtss>
-    /// <https://www.felixcloutier.com/x86/rsqrtps>
-    Rsqrt,
-}
-
-/// Performs `which` scalar operation on `op` and returns the result.
-#[allow(clippy::arithmetic_side_effects)] // floating point operations without side effects
-fn unary_op_f32<'tcx>(
-    this: &mut crate::MiriInterpCx<'_, 'tcx>,
-    which: FloatUnaryOp,
-    op: &ImmTy<'tcx, Provenance>,
-) -> InterpResult<'tcx, Scalar<Provenance>> {
-    match which {
-        FloatUnaryOp::Sqrt => {
-            let op = op.to_scalar();
-            // FIXME using host floats
-            Ok(Scalar::from_u32(f32::from_bits(op.to_u32()?).sqrt().to_bits()))
-        }
-        FloatUnaryOp::Rcp => {
-            let op = op.to_scalar().to_f32()?;
-            let div = (Single::from_u128(1).value / op).value;
-            // Apply a relative error with a magnitude on the order of 2^-12 to simulate the
-            // inaccuracy of RCP.
-            let res = apply_random_float_error(this, div, -12);
-            Ok(Scalar::from_f32(res))
-        }
-        FloatUnaryOp::Rsqrt => {
-            let op = op.to_scalar().to_u32()?;
-            // FIXME using host floats
-            let sqrt = Single::from_bits(f32::from_bits(op).sqrt().to_bits().into());
-            let rsqrt = (Single::from_u128(1).value / sqrt).value;
-            // Apply a relative error with a magnitude on the order of 2^-12 to simulate the
-            // inaccuracy of RSQRT.
-            let res = apply_random_float_error(this, rsqrt, -12);
-            Ok(Scalar::from_f32(res))
-        }
-    }
-}
-
-/// Disturbes a floating-point result by a relative error on the order of (-2^scale, 2^scale).
-#[allow(clippy::arithmetic_side_effects)] // floating point arithmetic cannot panic
-fn apply_random_float_error<F: rustc_apfloat::Float>(
-    this: &mut crate::MiriInterpCx<'_, '_>,
-    val: F,
-    err_scale: i32,
-) -> F {
-    let rng = this.machine.rng.get_mut();
-    // generates rand(0, 2^64) * 2^(scale - 64) = rand(0, 1) * 2^scale
-    let err =
-        F::from_u128(rng.gen::<u64>().into()).value.scalbn(err_scale.checked_sub(64).unwrap());
-    // give it a random sign
-    let err = if rng.gen::<bool>() { -err } else { err };
-    // multiple the value with (1+err)
-    (val * (F::from_u128(1).value + err).value).value
-}
-
-/// Performs `which` operation on the first component of `op` and copies
-/// the other components. The result is stored in `dest`.
-fn unary_op_ss<'tcx>(
-    this: &mut crate::MiriInterpCx<'_, 'tcx>,
-    which: FloatUnaryOp,
-    op: &OpTy<'tcx, Provenance>,
-    dest: &PlaceTy<'tcx, Provenance>,
-) -> InterpResult<'tcx, ()> {
-    let (op, op_len) = this.operand_to_simd(op)?;
-    let (dest, dest_len) = this.place_to_simd(dest)?;
-
-    assert_eq!(dest_len, op_len);
-
-    let res0 = unary_op_f32(this, which, &this.read_immediate(&this.project_index(&op, 0)?)?)?;
-    this.write_scalar(res0, &this.project_index(&dest, 0)?)?;
-
-    for i in 1..dest_len {
-        this.copy_op(
-            &this.project_index(&op, i)?,
-            &this.project_index(&dest, i)?,
-            /*allow_transmute*/ false,
-        )?;
-    }
-
-    Ok(())
-}
-
-/// Performs `which` operation on each component of `op`, storing the
-/// result is stored in `dest`.
-fn unary_op_ps<'tcx>(
-    this: &mut crate::MiriInterpCx<'_, 'tcx>,
-    which: FloatUnaryOp,
-    op: &OpTy<'tcx, Provenance>,
-    dest: &PlaceTy<'tcx, Provenance>,
-) -> InterpResult<'tcx, ()> {
-    let (op, op_len) = this.operand_to_simd(op)?;
-    let (dest, dest_len) = this.place_to_simd(dest)?;
-
-    assert_eq!(dest_len, op_len);
-
-    for i in 0..dest_len {
-        let op = this.read_immediate(&this.project_index(&op, i)?)?;
-        let dest = this.project_index(&dest, i)?;
-
-        let res = unary_op_f32(this, which, &op)?;
-        this.write_scalar(res, &dest)?;
-    }
-
-    Ok(())
-}