Add vshuf.h

docs/lsx_misc/vshuf.md

@@ -15,14 +15,43 @@ CPU Flags: LSX
 
 Shuffle bytes from `a` and `b` with indices from `c`.
 
+Caveat: the indices are placed in `c`, while in other `vshuf` intrinsics they are placed in `a`.
+
 ### Operation
 
 ```c++
 for (int i = 0;i < 16;i++) {
-    if (c.byte[i] % 32 < 16) {
+    if ((c.byte[i] % 32) < 16) {
         dst.byte[i] = b.byte[c.byte[i] % 16];
     } else {
         dst.byte[i] = a.byte[c.byte[i] % 16];
     }
 }
 ```
+
+## __m128i __lsx_vshuf_h (__m128i a, __m128i b, __m128i c)
+
+### Synopsis
+
+```c++
+__m128i __lsx_vshuf_h (__m128i a, __m128i b, __m128i c)
+#include <lsxintrin.h>
+Instruction: vshuf.h vr, vr, vr
+CPU Flags: LSX
+```
+
+### Description
+
+Shuffle half words from `b` and `c` with indices from `a`.
+
+### Operation
+
+```c++
+for (int i = 0;i < 8;i++) {
+    if ((c.half[i] % 16) < 8) {
+        dst.half[i] = c.half[a.half[i] % 8];
+    } else {
+        dst.half[i] = b.half[a.half[i] % 8];
+    }
+}
+```