--- old/src/hotspot/share/utilities/globalDefinitions.hpp	2018-11-09 10:28:52.740737605 +0100
+++ new/src/hotspot/share/utilities/globalDefinitions.hpp	2018-11-09 10:28:44.165710689 +0100
@@ -1043,10 +1043,10 @@
 // Returns largest i such that 2^i <= x.
 // If x < 0, the function returns 31 on a 32-bit machine and 63 on a 64-bit machine.
 // If x == 0, the function returns -1.
-inline int log2_intptr(intptr_t x) {
+inline int log2_intptr(uintptr_t x) {
   int i = -1;
   uintptr_t p = 1;
-  while (p != 0 && p <= (uintptr_t)x) {
+  while (p != 0 && p <= x) {
     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
     i++; p *= 2;
   }
@@ -1057,10 +1057,10 @@
 
 //* largest i such that 2^i <= x
 //  A negative value of 'x' will return '63'
-inline int log2_long(jlong x) {
+inline int log2_long(unsigned long x) {
   int i = -1;
   julong p =  1;
-  while (p != 0 && p <= (julong)x) {
+  while (p != 0 && p <= x) {
     // p = 2^(i+1) && p <= x (i.e., 2^(i+1) <= x)
     i++; p *= 2;
   }
@@ -1069,6 +1069,22 @@
   return i;
 }
 
+inline int log2_intptr(intptr_t x) {
+  return log2_intptr((uintptr_t)x);
+}
+
+inline int log2_intptr(int x) {
+  return log2_intptr((uintptr_t)x);
+}
+
+inline int log2_intptr(uint x) {
+  return log2_intptr((uintptr_t)x);
+}
+
+inline int log2_long(long x) {
+  return log2_long((unsigned long)x);
+}
+
 //* the argument must be exactly a power of 2
 inline int exact_log2(intptr_t x) {
   assert(is_power_of_2(x), "x must be a power of 2: " INTPTR_FORMAT, x);
@@ -1084,6 +1100,29 @@
 inline bool is_odd (intx x) { return x & 1;      }
 inline bool is_even(intx x) { return !is_odd(x); }
 
+// abs methods which cannot overflow and so are well-defined across
+// the entire domain of integer types.
+static inline unsigned int uabs(unsigned int n) {
+  union {
+    unsigned int result;
+    int value;
+  };
+  result = n;
+  if (value < 0) result = -result;
+  return result;
+}
+static inline unsigned long uabs(unsigned long n) {
+  union {
+    unsigned long result;
+    long value;
+  };
+  result = n;
+  if (value < 0) result = -result;
+  return result;
+}
+static inline unsigned long uabs(long n) { return uabs((unsigned long)n); }
+static inline unsigned int uabs(int n) { return uabs((unsigned int)n); }
+
 // "to" should be greater than "from."
 inline intx byte_size(void* from, void* to) {
   return (address)to - (address)from;