ptrOffset and ptrDiff do not truncate uint64_t to uintptr_t

Change-Id: I0dcaf058ae3244ca0168580d972a19f9e4692e05
Signed-off-by: Venevtsev, Igor <igor.venevtsev@intel.com>

Author: ivvenevt

runtime/helpers/ptr_math.h

@@ -23,13 +23,23 @@ inline T ptrOffset(T ptrBefore, size_t offset) {
     return (T)addrAfter;
 }
 
+template <>
+inline uint64_t ptrOffset(uint64_t ptrBefore, size_t offset) {
+    return ptrBefore + offset;
+}
+
 template <typename TA, typename TB>
 inline size_t ptrDiff(TA ptrAfter, TB ptrBefore) {
     auto addrBefore = (uintptr_t)ptrBefore;
     auto addrAfter = (uintptr_t)ptrAfter;
     return addrAfter - addrBefore;
 }
 
+template <typename T>
+inline uint64_t ptrDiff(uint64_t ptrAfter, T ptrBefore) {
+    return ptrAfter - ptrBefore;
+}
+
 template <typename IntegerAddressType>
 inline void *addrToPtr(IntegerAddressType addr) {
     uintptr_t correctBitnessAddress = static_cast<uintptr_t>(addr);

unit_tests/helpers/ptr_math_tests.cpp

@@ -45,3 +45,23 @@ TEST(PtrMath, givenCastToUint64FunctionWhenItIsCalledThenProperValueIsReturned)
     auto uintAddress = castToUint64(addressWithTrailingBitSet);
     EXPECT_EQ(uintAddress, expectedUint64Address);
 }
+
+TEST(ptrOffset, preserve64Bit) {
+    uint64_t ptrBefore = 0x800000000;
+    size_t offset = 0x1234;
+    auto ptrAfter = ptrOffset(ptrBefore, offset);
+    EXPECT_EQ(0x800001234ull, ptrAfter);
+}
+
+TEST(ptrDiff, preserve64Bit) {
+    auto ptrAfter = 0x800001234ull;
+
+    auto ptrBefore = ptrDiff(ptrAfter, (size_t)0x1234);
+    EXPECT_EQ(0x800000000ull, ptrBefore);
+
+    auto ptrBefore2 = ptrDiff(ptrAfter, 0x1234);
+    EXPECT_EQ(0x800000000ull, ptrBefore2);
+
+    auto ptrBefore3 = ptrDiff(ptrAfter, 0x1234ull);
+    EXPECT_EQ(0x800000000ull, ptrBefore3);
+}