8336297: C2: Fix -Wzero-as-null-pointer-constant warnings in derived Node ctors

Reviewed-by: kvn, jwaters

Author: Kim Barrett

src/hotspot/share/opto/graphKit.cpp

@@ -1209,7 +1209,7 @@ Node* GraphKit::load_array_length(Node* array) {
   Node *alen;
   if (alloc == nullptr) {
     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
-    alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
+    alen = _gvn.transform( new LoadRangeNode(nullptr, immutable_memory(), r_adr, TypeInt::POS));
   } else {
     alen = array_ideal_length(alloc, _gvn.type(array)->is_oopptr(), false);
   }
@@ -2385,7 +2385,7 @@ Node* GraphKit::precision_rounding(Node* n) {
   if (Matcher::strict_fp_requires_explicit_rounding) {
 #ifdef IA32
     if (UseSSE == 0) {
-      return _gvn.transform(new RoundFloatNode(0, n));
+      return _gvn.transform(new RoundFloatNode(nullptr, n));
     }
 #else
     Unimplemented();
@@ -2399,7 +2399,7 @@ Node* GraphKit::dprecision_rounding(Node *n) {
   if (Matcher::strict_fp_requires_explicit_rounding) {
 #ifdef IA32
     if (UseSSE < 2) {
-      return _gvn.transform(new RoundDoubleNode(0, n));
+      return _gvn.transform(new RoundDoubleNode(nullptr, n));
     }
 #else
     Unimplemented();
@@ -3489,7 +3489,7 @@ FastLockNode* GraphKit::shared_lock(Node* obj) {
   box = _gvn.transform(box);
   Node* mem = reset_memory();
 
-  FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
+  FastLockNode * flock = _gvn.transform(new FastLockNode(nullptr, obj, box) )->as_FastLock();
 
   // Add monitor to debug info for the slow path.  If we block inside the
   // slow path and de-opt, we need the monitor hanging around

src/hotspot/share/opto/library_call.cpp

@@ -2138,12 +2138,12 @@ bool LibraryCallKit::inline_number_methods(vmIntrinsics::ID id) {
   case vmIntrinsics::_numberOfTrailingZeros_l:  n = new CountTrailingZerosLNode(arg);  break;
   case vmIntrinsics::_bitCount_i:               n = new PopCountINode(          arg);  break;
   case vmIntrinsics::_bitCount_l:               n = new PopCountLNode(          arg);  break;
-  case vmIntrinsics::_reverseBytes_c:           n = new ReverseBytesUSNode(0,   arg);  break;
-  case vmIntrinsics::_reverseBytes_s:           n = new ReverseBytesSNode( 0,   arg);  break;
-  case vmIntrinsics::_reverseBytes_i:           n = new ReverseBytesINode( 0,   arg);  break;
-  case vmIntrinsics::_reverseBytes_l:           n = new ReverseBytesLNode( 0,   arg);  break;
-  case vmIntrinsics::_reverse_i:                n = new ReverseINode(0, arg); break;
-  case vmIntrinsics::_reverse_l:                n = new ReverseLNode(0, arg); break;
+  case vmIntrinsics::_reverseBytes_c:           n = new ReverseBytesUSNode(nullptr, arg);  break;
+  case vmIntrinsics::_reverseBytes_s:           n = new ReverseBytesSNode( nullptr, arg);  break;
+  case vmIntrinsics::_reverseBytes_i:           n = new ReverseBytesINode( nullptr, arg);  break;
+  case vmIntrinsics::_reverseBytes_l:           n = new ReverseBytesLNode( nullptr, arg);  break;
+  case vmIntrinsics::_reverse_i:                n = new ReverseINode(nullptr, arg); break;
+  case vmIntrinsics::_reverse_l:                n = new ReverseLNode(nullptr, arg); break;
   default:  fatal_unexpected_iid(id);  break;
   }
   set_result(_gvn.transform(n));

src/hotspot/share/opto/loopnode.cpp

@@ -2591,7 +2591,7 @@ Node *LoopLimitNode::Ideal(PhaseGVN *phase, bool can_reshape) {
     Node* stride_m = phase->intcon(stride_con - (stride_con > 0 ? 1 : -1));
     Node *range = phase->transform(new SubINode(in(Limit), in(Init)));
     Node *bias  = phase->transform(new AddINode(range, stride_m));
-    Node *trip  = phase->transform(new DivINode(0, bias, in(Stride)));
+    Node *trip  = phase->transform(new DivINode(nullptr, bias, in(Stride)));
     Node *span  = phase->transform(new MulINode(trip, in(Stride)));
     return new AddINode(span, in(Init)); // exact limit
   }
@@ -2620,7 +2620,7 @@ Node *LoopLimitNode::Ideal(PhaseGVN *phase, bool can_reshape) {
       Node* neg_stride   = phase->longcon(-stride_con);
       span = phase->transform(new AndLNode(bias, neg_stride));
     } else {
-      Node *trip  = phase->transform(new DivLNode(0, bias, stride));
+      Node *trip  = phase->transform(new DivLNode(nullptr, bias, stride));
       span = phase->transform(new MulLNode(trip, stride));
     }
     // Convert back to int

src/hotspot/share/opto/parse1.cpp

@@ -251,7 +251,7 @@ void Parse::load_interpreter_state(Node* osr_buf) {
 
     // Build a bogus FastLockNode (no code will be generated) and push the
     // monitor into our debug info.
-    const FastLockNode *flock = _gvn.transform(new FastLockNode( 0, lock_object, box ))->as_FastLock();
+    const FastLockNode *flock = _gvn.transform(new FastLockNode( nullptr, lock_object, box ))->as_FastLock();
     map()->push_monitor(flock);
 
     // If the lock is our method synchronization lock, tuck it away in

src/hotspot/share/opto/parse2.cpp

@@ -2233,7 +2233,7 @@ void Parse::do_one_bytecode() {
   case Bytecodes::_fdiv:
     b = pop();
     a = pop();
-    c = _gvn.transform( new DivFNode(0,a,b) );
+    c = _gvn.transform( new DivFNode(nullptr,a,b) );
     d = precision_rounding(c);
     push( d );
     break;
@@ -2243,7 +2243,7 @@ void Parse::do_one_bytecode() {
       // Generate a ModF node.
       b = pop();
       a = pop();
-      c = _gvn.transform( new ModFNode(0,a,b) );
+      c = _gvn.transform( new ModFNode(nullptr,a,b) );
       d = precision_rounding(c);
       push( d );
     }
@@ -2294,7 +2294,7 @@ void Parse::do_one_bytecode() {
     a = pop_pair();
     b = _gvn.transform( new ConvD2FNode(a));
     // This breaks _227_mtrt (speed & correctness) and _222_mpegaudio (speed)
-    //b = _gvn.transform(new RoundFloatNode(0, b) );
+    //b = _gvn.transform(new RoundFloatNode(nullptr, b) );
     push( b );
     break;
 
@@ -2360,7 +2360,7 @@ void Parse::do_one_bytecode() {
   case Bytecodes::_ddiv:
     b = pop_pair();
     a = pop_pair();
-    c = _gvn.transform( new DivDNode(0,a,b) );
+    c = _gvn.transform( new DivDNode(nullptr,a,b) );
     d = dprecision_rounding(c);
     push_pair( d );
     break;
@@ -2378,7 +2378,7 @@ void Parse::do_one_bytecode() {
       a = pop_pair();
       // a % b
 
-      c = _gvn.transform( new ModDNode(0,a,b) );
+      c = _gvn.transform( new ModDNode(nullptr,a,b) );
       d = dprecision_rounding(c);
       push_pair( d );
     }