1.1 --- a/src/share/vm/opto/divnode.cpp Tue Jun 12 10:02:36 2012 +0200
1.2 +++ b/src/share/vm/opto/divnode.cpp Tue Jun 12 09:47:23 2012 -0700
1.3 @@ -284,9 +284,14 @@
1.4
1.5 const int N = 64;
1.6
1.7 + // Dummy node to keep intermediate nodes alive during construction
1.8 + Node* hook = new (phase->C, 4) Node(4);
1.9 +
1.10 // u0 = u & 0xFFFFFFFF; u1 = u >> 32;
1.11 Node* u0 = phase->transform(new (phase->C, 3) AndLNode(dividend, phase->longcon(0xFFFFFFFF)));
1.12 Node* u1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N / 2)));
1.13 + hook->init_req(0, u0);
1.14 + hook->init_req(1, u1);
1.15
1.16 // v0 = v & 0xFFFFFFFF; v1 = v >> 32;
1.17 Node* v0 = phase->longcon(magic_const & 0xFFFFFFFF);
1.18 @@ -299,19 +304,14 @@
1.19 Node* u1v0 = phase->transform(new (phase->C, 3) MulLNode(u1, v0));
1.20 Node* temp = phase->transform(new (phase->C, 3) URShiftLNode(w0, phase->intcon(N / 2)));
1.21 Node* t = phase->transform(new (phase->C, 3) AddLNode(u1v0, temp));
1.22 + hook->init_req(2, t);
1.23
1.24 // w1 = t & 0xFFFFFFFF;
1.25 - Node* w1 = new (phase->C, 3) AndLNode(t, phase->longcon(0xFFFFFFFF));
1.26 + Node* w1 = phase->transform(new (phase->C, 3) AndLNode(t, phase->longcon(0xFFFFFFFF)));
1.27 + hook->init_req(3, w1);
1.28
1.29 // w2 = t >> 32;
1.30 - Node* w2 = new (phase->C, 3) RShiftLNode(t, phase->intcon(N / 2));
1.31 -
1.32 - // 6732154: Construct both w1 and w2 before transforming, so t
1.33 - // doesn't go dead prematurely.
1.34 - // 6837011: We need to transform w2 before w1 because the
1.35 - // transformation of w1 could return t.
1.36 - w2 = phase->transform(w2);
1.37 - w1 = phase->transform(w1);
1.38 + Node* w2 = phase->transform(new (phase->C, 3) RShiftLNode(t, phase->intcon(N / 2)));
1.39
1.40 // w1 = u0*v1 + w1;
1.41 Node* u0v1 = phase->transform(new (phase->C, 3) MulLNode(u0, v1));
1.42 @@ -322,6 +322,16 @@
1.43 Node* temp1 = phase->transform(new (phase->C, 3) AddLNode(u1v1, w2));
1.44 Node* temp2 = phase->transform(new (phase->C, 3) RShiftLNode(w1, phase->intcon(N / 2)));
1.45
1.46 + // Remove the bogus extra edges used to keep things alive
1.47 + PhaseIterGVN* igvn = phase->is_IterGVN();
1.48 + if (igvn != NULL) {
1.49 + igvn->remove_dead_node(hook);
1.50 + } else {
1.51 + for (int i = 0; i < 4; i++) {
1.52 + hook->set_req(i, NULL);
1.53 + }
1.54 + }
1.55 +
1.56 return new (phase->C, 3) AddLNode(temp1, temp2);
1.57 }
1.58
