Add bindings for _mm_blendv_epi8

Just wanted to test this out!

Author: alexcrichton

src/x86/mod.rs

@@ -1,6 +1,7 @@
 pub use self::sse::*;
 pub use self::sse2::*;
 pub use self::ssse3::*;
+pub use self::sse41::*;
 pub use self::sse42::*;
 pub use self::avx::*;
 pub use self::avx2::*;
@@ -13,6 +14,7 @@ pub type __m256i = ::v256::i8x32;
 mod sse;
 mod sse2;
 mod ssse3;
+mod sse41;
 mod sse42;
 mod avx;
-mod avx2;
+mod avx2;

src/x86/sse41.rs

@@ -0,0 +1,38 @@
+// use v128::*;
+use x86::__m128i;
+
+#[inline(always)]
+#[target_feature = "+sse4.1"]
+pub fn _mm_blendv_epi8(
+    a: __m128i,
+    b: __m128i,
+    mask: __m128i,
+) -> __m128i {
+    unsafe { pblendvb(a, b, mask) }
+}
+
+#[allow(improper_ctypes)]
+extern {
+    #[link_name = "llvm.x86.sse41.pblendvb"]
+    fn pblendvb(a: __m128i, b: __m128i, mask: __m128i) -> __m128i;
+}
+
+#[cfg(test)]
+mod tests {
+    use v128::*;
+    use x86::sse41;
+
+    #[test]
+    #[target_feature = "+sse4.2"]
+    fn _mm_blendv_epi8() {
+        let a = i8x16::new(
+            0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+        let b = i8x16::new(
+            16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31);
+        let mask = i8x16::new(
+            0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1);
+        let e = i8x16::new(
+            0, 17, 2, 19, 4, 21, 6, 23, 8, 25, 10, 27, 12, 29, 14, 31);
+        assert_eq!(sse41::_mm_blendv_epi8(a, b, mask), e);
+    }
+}