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Diffstat (limited to 'gcc/f/runtime/libF77/lbitbits.c')
-rw-r--r--gcc/f/runtime/libF77/lbitbits.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/gcc/f/runtime/libF77/lbitbits.c b/gcc/f/runtime/libF77/lbitbits.c
new file mode 100644
index 00000000000..75e9f9c603f
--- /dev/null
+++ b/gcc/f/runtime/libF77/lbitbits.c
@@ -0,0 +1,62 @@
+#include "f2c.h"
+
+#ifndef LONGBITS
+#define LONGBITS 32
+#endif
+
+ integer
+#ifdef KR_headers
+lbit_bits(a, b, len) integer a, b, len;
+#else
+lbit_bits(integer a, integer b, integer len)
+#endif
+{
+ /* Assume 2's complement arithmetic */
+
+ unsigned long x, y;
+
+ x = (unsigned long) a;
+ y = (unsigned long)-1L;
+ x >>= b;
+ y <<= len;
+ return (integer)(x & ~y);
+ }
+
+ integer
+#ifdef KR_headers
+lbit_cshift(a, b, len) integer a, b, len;
+#else
+lbit_cshift(integer a, integer b, integer len)
+#endif
+{
+ unsigned long x, y, z;
+
+ x = (unsigned long)a;
+ if (len <= 0) {
+ if (len == 0)
+ return 0;
+ goto full_len;
+ }
+ if (len >= LONGBITS) {
+ full_len:
+ if (b >= 0) {
+ b %= LONGBITS;
+ return (integer)(x << b | x >> LONGBITS -b );
+ }
+ b = -b;
+ b %= LONGBITS;
+ return (integer)(x << LONGBITS - b | x >> b);
+ }
+ y = z = (unsigned long)-1;
+ y <<= len;
+ z &= ~y;
+ y &= x;
+ x &= z;
+ if (b >= 0) {
+ b %= len;
+ return (integer)(y | z & (x << b | x >> len - b));
+ }
+ b = -b;
+ b %= len;
+ return (integer)(y | z & (x >> b | x << len - b));
+ }