add gather/scatter run-time test

src/test/codegen/simd-intrinsic-generic-gather.rs

@@ -10,6 +10,7 @@
 
 // ignore-emscripten
 // ignore-tidy-linelength
+// min-llvm-version 6.0
 
 // compile-flags: -C no-prepopulate-passes
 

src/test/codegen/simd-intrinsic-generic-scatter.rs

@@ -10,6 +10,7 @@
 
 // ignore-emscripten
 // ignore-tidy-linelength
+// min-llvm-version 6.0
 
 // compile-flags: -C no-prepopulate-passes
 
@@ -38,6 +39,7 @@ pub unsafe fn scatter_f32x2(pointers: Vec2<*mut f32>, mask: Vec2<i32>,
     simd_scatter(values, pointers, mask)
 }
 
+
 // CHECK-LABEL: @scatter_pf32x2
 #[no_mangle]
 pub unsafe fn scatter_pf32x2(pointers: Vec2<*mut *const f32>, mask: Vec2<i32>,

src/test/run-pass/simd-intrinsic-generic-gather.rs

@@ -0,0 +1,80 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// ignore-emscripten
+// min-llvm-version 6.0
+
+// Test that the simd_{gather,scatter} intrinsics produce the correct results.
+
+#![feature(repr_simd, platform_intrinsics)]
+#![allow(non_camel_case_types)]
+
+#[repr(simd)]
+#[derive(Copy, Clone, PartialEq, Debug)]
+struct x4<T>(pub T, pub T, pub T, pub T);
+
+extern "platform-intrinsic" {
+    fn simd_gather<T, U, V>(x: T, y: U, z: V) -> T;
+    fn simd_scatter<T, U, V>(x: T, y: U, z: V) -> ();
+}
+
+fn main() {
+    let mut x = [0_f32, 1., 2., 3., 4., 5., 6., 7.];
+
+    let default = x4(-3_f32, -3., -3., -3.);
+    let s_strided = x4(0_f32, 2., -3., 6.);
+    let mask = x4(-1_i32, -1, 0, -1);
+
+    // reading from *const
+    unsafe {
+        let pointer = &x[0] as *const f32;
+        let pointers =  x4(
+            pointer.offset(0) as *const f32,
+            pointer.offset(2),
+            pointer.offset(4),
+            pointer.offset(6)
+        );
+
+        let r_strided = simd_gather(default, pointers, mask);
+
+        assert_eq!(r_strided, s_strided);
+    }
+
+    // reading from *mut
+    unsafe {
+        let pointer = &mut x[0] as *mut f32;
+        let pointers = x4(
+            pointer.offset(0) as *mut f32,
+            pointer.offset(2),
+            pointer.offset(4),
+            pointer.offset(6)
+        );
+
+        let r_strided = simd_gather(default, pointers, mask);
+
+        assert_eq!(r_strided, s_strided);
+    }
+
+    // writing to *mut
+    unsafe {
+        let pointer = &mut x[0] as *mut f32;
+        let pointers = x4(
+            pointer.offset(0) as *mut f32,
+            pointer.offset(2),
+            pointer.offset(4),
+            pointer.offset(6)
+        );
+
+        let values = x4(42_f32, 43_f32, 44_f32, 45_f32);
+        simd_scatter(values, pointers, mask);
+
+        assert_eq!(x, [42., 1., 43., 3., 4., 5., 45., 7.]);
+    }
+}