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-rw-r--r--gcc/hwint.c74
1 files changed, 74 insertions, 0 deletions
diff --git a/gcc/hwint.c b/gcc/hwint.c
index 85c1326..a128dc1 100644
--- a/gcc/hwint.c
+++ b/gcc/hwint.c
@@ -21,6 +21,7 @@ along with GCC; see the file COPYING3. If not see
#include "config.h"
#include "system.h"
+#include "diagnostic-core.h"
#if GCC_VERSION < 3004
@@ -98,3 +99,76 @@ ffs_hwi (unsigned HOST_WIDE_INT x)
}
#endif /* GCC_VERSION < 3004 */
+
+/* Compute the absolute value of X. */
+
+HOST_WIDE_INT
+abs_hwi (HOST_WIDE_INT x)
+{
+ gcc_checking_assert (x != HOST_WIDE_INT_MIN);
+ return x >= 0 ? x : -x;
+}
+
+/* Compute the greatest common divisor of two numbers A and B using
+ Euclid's algorithm. */
+
+HOST_WIDE_INT
+gcd (HOST_WIDE_INT a, HOST_WIDE_INT b)
+{
+ HOST_WIDE_INT x, y, z;
+
+ x = abs_hwi (a);
+ y = abs_hwi (b);
+
+ while (x > 0)
+ {
+ z = y % x;
+ y = x;
+ x = z;
+ }
+
+ return y;
+}
+
+/* For X and Y positive integers, return X multiplied by Y and check
+ that the result does not overflow. */
+
+HOST_WIDE_INT
+pos_mul_hwi (HOST_WIDE_INT x, HOST_WIDE_INT y)
+{
+ if (x != 0)
+ gcc_checking_assert ((HOST_WIDE_INT_MAX) / x >= y);
+
+ return x * y;
+}
+
+/* Return X multiplied by Y and check that the result does not
+ overflow. */
+
+HOST_WIDE_INT
+mul_hwi (HOST_WIDE_INT x, HOST_WIDE_INT y)
+{
+ gcc_checking_assert (x != HOST_WIDE_INT_MIN
+ && y != HOST_WIDE_INT_MIN);
+
+ if (x >= 0)
+ {
+ if (y >= 0)
+ return pos_mul_hwi (x, y);
+
+ return -pos_mul_hwi (x, -y);
+ }
+
+ if (y >= 0)
+ return -pos_mul_hwi (-x, y);
+
+ return pos_mul_hwi (-x, -y);
+}
+
+/* Compute the least common multiple of two numbers A and B . */
+
+HOST_WIDE_INT
+least_common_multiple (HOST_WIDE_INT a, HOST_WIDE_INT b)
+{
+ return mul_hwi (abs_hwi (a) / gcd (a, b), abs_hwi (b));
+}