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Diffstat (limited to 'gcc/f/runtime/libF77/pow_ri.c')
-rw-r--r--gcc/f/runtime/libF77/pow_ri.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/gcc/f/runtime/libF77/pow_ri.c b/gcc/f/runtime/libF77/pow_ri.c
new file mode 100644
index 00000000000..6e5816bbf10
--- /dev/null
+++ b/gcc/f/runtime/libF77/pow_ri.c
@@ -0,0 +1,35 @@
+#include "f2c.h"
+
+#ifdef KR_headers
+double pow_ri(ap, bp) real *ap; integer *bp;
+#else
+double pow_ri(real *ap, integer *bp)
+#endif
+{
+double pow, x;
+integer n;
+unsigned long u;
+
+pow = 1;
+x = *ap;
+n = *bp;
+
+if(n != 0)
+ {
+ if(n < 0)
+ {
+ n = -n;
+ x = 1/x;
+ }
+ for(u = n; ; )
+ {
+ if(u & 01)
+ pow *= x;
+ if(u >>= 1)
+ x *= x;
+ else
+ break;
+ }
+ }
+return(pow);
+}