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-rw-r--r--libf2c/libF77/qbitbits.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/libf2c/libF77/qbitbits.c b/libf2c/libF77/qbitbits.c
new file mode 100644
index 0000000..f72858e
--- /dev/null
+++ b/libf2c/libF77/qbitbits.c
@@ -0,0 +1,62 @@
+#include "f2c.h"
+
+#ifndef LONGBITS
+#define LONGBITS 32
+#endif
+
+#ifndef LONG8BITS
+#define LONG8BITS (2*LONGBITS)
+#endif
+
+integer
+qbit_bits (longint a, integer b, integer len)
+{
+ /* Assume 2's complement arithmetic */
+
+ ulongint x, y;
+
+ x = (ulongint) a;
+ y = (ulongint) - 1L;
+ x >>= b;
+ y <<= len;
+ return (longint) (x & y);
+}
+
+longint
+qbit_cshift (longint a, integer b, integer len)
+{
+ ulongint x, y, z;
+
+ x = (ulongint) a;
+ if (len <= 0)
+ {
+ if (len == 0)
+ return 0;
+ goto full_len;
+ }
+ if (len >= LONG8BITS)
+ {
+ full_len:
+ if (b >= 0)
+ {
+ b %= LONG8BITS;
+ return (longint) (x << b | x >> (LONG8BITS - b));
+ }
+ b = -b;
+ b %= LONG8BITS;
+ return (longint) (x << (LONG8BITS - b) | x >> b);
+ }
+ y = z = (unsigned long) -1;
+ y <<= len;
+ z &= ~y;
+ y &= x;
+ x &= z;
+ if (b >= 0)
+ {
+ b %= len;
+ return (longint) (y | (z & (x << b | x >> (len - b))));
+ }
+ b = -b;
+ b %= len;
+ return (longint) (y | (z & (x >> b | x << (len - b))));
+}
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