1.1 --- a/src/share/vm/opto/subnode.cpp Thu Feb 16 15:14:44 2017 -0800
1.2 +++ b/src/share/vm/opto/subnode.cpp Thu Mar 30 15:28:33 2017 +0200
1.3 @@ -707,6 +707,60 @@
1.4 return TypeInt::CC; // else use worst case results
1.5 }
1.6
1.7 +
1.8 +// Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
1.9 +// If both inputs are constants, compare them.
1.10 +const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
1.11 + assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
1.12 +
1.13 + // comparing two unsigned longs
1.14 + const TypeLong* r0 = t1->is_long(); // Handy access
1.15 + const TypeLong* r1 = t2->is_long();
1.16 +
1.17 + // Current installed version
1.18 + // Compare ranges for non-overlap
1.19 + julong lo0 = r0->_lo;
1.20 + julong hi0 = r0->_hi;
1.21 + julong lo1 = r1->_lo;
1.22 + julong hi1 = r1->_hi;
1.23 +
1.24 + // If either one has both negative and positive values,
1.25 + // it therefore contains both 0 and -1, and since [0..-1] is the
1.26 + // full unsigned range, the type must act as an unsigned bottom.
1.27 + bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
1.28 + bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
1.29 +
1.30 + if (bot0 || bot1) {
1.31 + // All unsigned values are LE -1 and GE 0.
1.32 + if (lo0 == 0 && hi0 == 0) {
1.33 + return TypeInt::CC_LE; // 0 <= bot
1.34 + } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
1.35 + return TypeInt::CC_GE; // -1 >= bot
1.36 + } else if (lo1 == 0 && hi1 == 0) {
1.37 + return TypeInt::CC_GE; // bot >= 0
1.38 + } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
1.39 + return TypeInt::CC_LE; // bot <= -1
1.40 + }
1.41 + } else {
1.42 + // We can use ranges of the form [lo..hi] if signs are the same.
1.43 + assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
1.44 + // results are reversed, '-' > '+' for unsigned compare
1.45 + if (hi0 < lo1) {
1.46 + return TypeInt::CC_LT; // smaller
1.47 + } else if (lo0 > hi1) {
1.48 + return TypeInt::CC_GT; // greater
1.49 + } else if (hi0 == lo1 && lo0 == hi1) {
1.50 + return TypeInt::CC_EQ; // Equal results
1.51 + } else if (lo0 >= hi1) {
1.52 + return TypeInt::CC_GE;
1.53 + } else if (hi0 <= lo1) {
1.54 + return TypeInt::CC_LE;
1.55 + }
1.56 + }
1.57 +
1.58 + return TypeInt::CC; // else use worst case results
1.59 +}
1.60 +
1.61 //=============================================================================
1.62 //------------------------------sub--------------------------------------------
1.63 // Simplify an CmpP (compare 2 pointers) node, based on local information.
