Fix xvftint_w_d code, reported by Yang Liu

code/xvftint_w_d.cpp

@@ -0,0 +1,19 @@
+#include "common.h"
+
+v256 xvftint_w_d(v256 a, v256 b) {
+  v256 dst;
+#include "xvftint_w_d.h"
+  return dst;
+}
+
+void test() {
+  {
+    __m256d a = {1.0, 2.0, 3.0, 4.0};
+    __m256d b = {5.0, 6.0, 7.0, 8.0};
+    PRINT(a);
+    PRINT(b);
+    PRINT(__lasx_xvftint_w_d(a, b));
+    PRINT(xvftint_w_d(a, b));
+    assert(xvftint_w_d(a, b) == __lasx_xvftint_w_d(a, b));
+  }
+}

code/xvftint_w_d.h

@@ -1,5 +1,10 @@
 for (int i = 0; i < 4; i++) {
-  dst.dword[i] = (i < 2)
-                     ? (s64)a.fp64[i]
-                     : (s64)b.fp64[i]; // rounding mode is not expressed in C
+  dst.word[i] = (i < 2)
+                    ? (s64)b.fp64[i]
+                    : (s64)a.fp64[i - 2]; // rounding mode is not expressed in C
+}
+for (int i = 4; i < 8; i++) {
+  dst.word[i] = (i < 6)
+                    ? (s64)b.fp64[i - 2]
+                    : (s64)a.fp64[i - 4]; // rounding mode is not expressed in C
 }