added Shibatch nsfft lib support to supereq

1 files changed, 39 insertions, 0 deletions

diff --git a/plugins/supereq/shibatch_rdft.c b/plugins/supereq/shibatch_rdft.c
new file mode 100644
index 00000000..2a352f7e
--- /dev/null
+++ b/plugins/supereq/shibatch_rdft.c
@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <stdint.h>
+
+#include "SIMDBase.h"
+#include "DFT.h"
+
+typedef float REAL;
+#define TYPE SIMDBase_TYPE_FLOAT
+
+void rfft(int n,int isign,REAL *x) {
+    static DFT *p = NULL;
+    static int ipsize = 0;
+    static int mode = 0;
+    int newipsize;
+    if (n == 0) {
+        if (p) {
+            DFT_dispose(p, mode);
+            p = NULL;
+        }
+        return;
+    }
+    n = 1 << n;
+    newipsize = 2+sqrt(n/2);
+    if (newipsize > ipsize) {
+        ipsize = newipsize;
+
+        if (p) {
+            DFT_dispose(p, mode);
+            p = NULL;
+        }
+
+        mode = SIMDBase_chooseBestMode(TYPE);
+        p = DFT_init(mode, n, 0);
+    }
+
+    DFT_execute(p, mode, x, 1);
+}