Mercurial > jdk8-mips64-public > hotspot / changeset

     1.1 --- a/src/share/vm/opto/parse2.cpp	Fri Feb 29 19:57:41 2008 -0800
     1.2 +++ b/src/share/vm/opto/parse2.cpp	Wed Mar 05 11:33:31 2008 -0800
     1.3 @@ -1022,10 +1022,27 @@
     1.4    Node* tst = _gvn.transform(tst0);
     1.5    BoolTest::mask taken_btest   = BoolTest::illegal;
     1.6    BoolTest::mask untaken_btest = BoolTest::illegal;
     1.7 -  if (btest == BoolTest::ne) {
     1.8 -    // For now, these are the only cases of btest that matter.  (More later.)
     1.9 -    taken_btest   = taken_if_true ?        btest : BoolTest::eq;
    1.10 -    untaken_btest = taken_if_true ? BoolTest::eq :        btest;
    1.11 +
    1.12 +  if (tst->is_Bool()) {
    1.13 +    // Refresh c from the transformed bool node, since it may be
    1.14 +    // simpler than the original c.  Also re-canonicalize btest.
    1.15 +    // This wins when (Bool ne (Conv2B p) 0) => (Bool ne (CmpP p NULL)).
    1.16 +    // That can arise from statements like: if (x instanceof C) ...
    1.17 +    if (tst != tst0) {
    1.18 +      // Canonicalize one more time since transform can change it.
    1.19 +      btest = tst->as_Bool()->_test._test;
    1.20 +      if (!BoolTest(btest).is_canonical()) {
    1.21 +        // Reverse edges one more time...
    1.22 +        tst   = _gvn.transform( tst->as_Bool()->negate(&_gvn) );
    1.23 +        btest = tst->as_Bool()->_test._test;
    1.24 +        assert(BoolTest(btest).is_canonical(), "sanity");
    1.25 +        taken_if_true = !taken_if_true;
    1.26 +      }
    1.27 +      c = tst->in(1);
    1.28 +    }
    1.29 +    BoolTest::mask neg_btest = BoolTest(btest).negate();
    1.30 +    taken_btest   = taken_if_true ?     btest : neg_btest;
    1.31 +    untaken_btest = taken_if_true ? neg_btest :     btest;
    1.32    }
    1.33  
    1.34    // Generate real control flow