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-rw-r--r--gcc/f/runtime/libF77/z_div.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/gcc/f/runtime/libF77/z_div.c b/gcc/f/runtime/libF77/z_div.c
new file mode 100644
index 00000000000..4a987ab255a
--- /dev/null
+++ b/gcc/f/runtime/libF77/z_div.c
@@ -0,0 +1,39 @@
+#include "f2c.h"
+
+#ifdef KR_headers
+extern VOID sig_die();
+VOID z_div(resx, a, b) doublecomplex *a, *b, *resx;
+#else
+extern void sig_die(char*, int);
+void z_div(doublecomplex *resx, doublecomplex *a, doublecomplex *b)
+#endif
+{
+double ratio, den;
+double abr, abi;
+doublecomplex res;
+
+if( (abr = b->r) < 0.)
+ abr = - abr;
+if( (abi = b->i) < 0.)
+ abi = - abi;
+if( abr <= abi )
+ {
+ if(abi == 0)
+ sig_die("complex division by zero", 1);
+ ratio = b->r / b->i ;
+ den = b->i * (1 + ratio*ratio);
+ res.r = (a->r*ratio + a->i) / den;
+ res.i = (a->i*ratio - a->r) / den;
+ }
+
+else
+ {
+ ratio = b->i / b->r ;
+ den = b->r * (1 + ratio*ratio);
+ res.r = (a->r + a->i*ratio) / den;
+ res.i = (a->i - a->r*ratio) / den;
+ }
+
+resx->r = res.r;
+resx->i = res.i;
+}