Add rounding functions

Author: calebzulawski

crates/core_simd/src/lib.rs

@@ -1,5 +1,5 @@
 #![no_std]
-#![feature(repr_simd, platform_intrinsics)]
+#![feature(repr_simd, platform_intrinsics, link_llvm_intrinsics, simd_ffi)]
 #![warn(missing_docs)]
 //! Portable SIMD module.
 
@@ -56,3 +56,5 @@ mod vectors_mask128;
 pub use vectors_mask128::*;
 mod vectors_masksize;
 pub use vectors_masksize::*;
+
+mod round;

crates/core_simd/src/round.rs

@@ -0,0 +1,124 @@
+macro_rules! implement {
+    {
+        impl $type:ident {
+            floor = $floor_intrinsic:literal,
+            ceil = $ceil_intrinsic:literal,
+            round = $round_intrinsic:literal,
+            trunc = $trunc_intrinsic:literal,
+        }
+    } => {
+        mod $type {
+            #[allow(improper_ctypes)]
+            extern "C" {
+                #[link_name = $floor_intrinsic]
+                fn floor_intrinsic(x: crate::$type) -> crate::$type;
+                #[link_name = $ceil_intrinsic]
+                fn ceil_intrinsic(x: crate::$type) -> crate::$type;
+                #[link_name = $round_intrinsic]
+                fn round_intrinsic(x: crate::$type) -> crate::$type;
+                #[link_name = $trunc_intrinsic]
+                fn trunc_intrinsic(x: crate::$type) -> crate::$type;
+            }
+
+            impl crate::$type {
+                /// Returns the largest integer less than or equal to each lane.
+                #[must_use = "method returns a new vector and does not mutate the original value"]
+                #[inline]
+                pub fn floor(self) -> Self {
+                    unsafe { floor_intrinsic(self) }
+                }
+
+                /// Returns the smallest integer greater than or equal to each lane.
+                #[must_use = "method returns a new vector and does not mutate the original value"]
+                #[inline]
+                pub fn ceil(self) -> Self {
+                    unsafe { ceil_intrinsic(self) }
+                }
+
+                /// Returns the nearest integer to each lane. Round half-way cases away from 0.0.
+                #[must_use = "method returns a new vector and does not mutate the original value"]
+                #[inline]
+                pub fn round(self) -> Self {
+                    unsafe { round_intrinsic(self) }
+                }
+
+                /// Returns the integer part of each lane.
+                #[must_use = "method returns a new vector and does not mutate the original value"]
+                #[inline]
+                pub fn trunc(self) -> Self {
+                    unsafe { trunc_intrinsic(self) }
+                }
+
+                /// Returns the fractional part of each lane.
+                #[must_use = "method returns a new vector and does not mutate the original value"]
+                #[inline]
+                pub fn fract(self) -> Self {
+                    self - self.trunc()
+                }
+            }
+        }
+    }
+}
+
+implement! {
+    impl f32x2 {
+        floor = "llvm.floor.v2f32",
+        ceil = "llvm.ceil.v2f32",
+        round = "llvm.round.v2f32",
+        trunc = "llvm.trunc.v2f32",
+    }
+}
+
+implement! {
+    impl f32x4 {
+        floor = "llvm.floor.v4f32",
+        ceil = "llvm.ceil.v4f32",
+        round = "llvm.round.v4f32",
+        trunc = "llvm.trunc.v4f32",
+    }
+}
+
+implement! {
+    impl f32x8 {
+        floor = "llvm.floor.v8f32",
+        ceil = "llvm.ceil.v8f32",
+        round = "llvm.round.v8f32",
+        trunc = "llvm.trunc.v8f32",
+    }
+}
+
+implement! {
+    impl f32x16 {
+        floor = "llvm.floor.v16f32",
+        ceil = "llvm.ceil.v16f32",
+        round = "llvm.round.v16f32",
+        trunc = "llvm.trunc.v16f32",
+    }
+}
+
+implement! {
+    impl f64x2 {
+        floor = "llvm.floor.v2f64",
+        ceil = "llvm.ceil.v2f64",
+        round = "llvm.round.v2f64",
+        trunc = "llvm.trunc.v2f64",
+    }
+}
+
+implement! {
+    impl f64x4 {
+        floor = "llvm.floor.v4f64",
+        ceil = "llvm.ceil.v4f64",
+        round = "llvm.round.v4f64",
+        trunc = "llvm.trunc.v4f64",
+    }
+}
+
+implement! {
+    impl f64x8 {
+        floor = "llvm.floor.v8f64",
+        ceil = "llvm.ceil.v8f64",
+        round = "llvm.round.v8f64",
+        trunc = "llvm.trunc.v8f64",
+    }
+}