src/share/vm/opto/library_call.cpp

rev 7387 : 8063137: Never-taken branches should be pruned when GWT LambdaForms are shared
Reviewed-by: ?

*** 39,48 ****
--- 39,49 ----
  #include "opto/idealKit.hpp"
  #include "opto/mathexactnode.hpp"
  #include "opto/movenode.hpp"
  #include "opto/mulnode.hpp"
  #include "opto/narrowptrnode.hpp"
+ #include "opto/opaquenode.hpp"
  #include "opto/parse.hpp"
  #include "opto/runtime.hpp"
  #include "opto/subnode.hpp"
  #include "prims/nativeLookup.hpp"
  #include "runtime/sharedRuntime.hpp"
*** 285,294 ****
--- 286,297 ----
    bool inline_encodeISOArray();
    bool inline_updateCRC32();
    bool inline_updateBytesCRC32();
    bool inline_updateByteBufferCRC32();
    bool inline_multiplyToLen();
+ 
+   bool inline_profileBranch();
  };
  
  
  //---------------------------make_vm_intrinsic----------------------------
  CallGenerator* Compile::make_vm_intrinsic(ciMethod* m, bool is_virtual) {
*** 898,907 ****
--- 901,913 ----
    case vmIntrinsics::_updateBytesCRC32:
      return inline_updateBytesCRC32();
    case vmIntrinsics::_updateByteBufferCRC32:
      return inline_updateByteBufferCRC32();
  
+   case vmIntrinsics::_profileBranch:
+     return inline_profileBranch();
+ 
    default:
      // If you get here, it may be that someone has added a new intrinsic
      // to the list in vmSymbols.hpp without implementing it here.
  #ifndef PRODUCT
      if ((PrintMiscellaneous && (Verbose || WizardMode)) || PrintOpto) {
*** 5805,5809 ****
--- 5811,5848 ----
    Node* bool_instof = _gvn.transform(new BoolNode(cmp_instof, BoolTest::ne));
    Node* instof_false = generate_guard(bool_instof, NULL, PROB_MIN);
  
    return instof_false;  // even if it is NULL
  }
+ 
+ bool LibraryCallKit::inline_profileBranch() {
+   Node* counts = argument(1);
+   const TypeAryPtr* ary = NULL;
+   ciArray* aobj = NULL;
+   if (counts->is_Con()
+       && (ary = counts->bottom_type()->isa_aryptr()) != NULL
+       && (aobj = ary->const_oop()->as_array()) != NULL) {
+     assert(aobj->length() == 2, "");
+     jint     taken = aobj->element_value(1).as_int();
+     jint not_taken = aobj->element_value(0).as_int();
+ 
+     if (C->log() != NULL) {
+       C->log()->elem("profile_branch taken='%d' not_taken='%d'",
+                      taken, not_taken);
+     }
+ 
+     if (taken + not_taken == 0) {
+       // According to profile, never executed.
+       uncommon_trap_exact(Deoptimization::Reason_intrinsic,
+                           Deoptimization::Action_reinterpret);
+       return true;
+     }
+     // Stop profiling
+     Node* opq = _gvn.transform(new Opaque4Node(argument(0), taken, not_taken));
+     C->record_for_igvn(opq);
+     set_result(opq);
+     return true;
+   } else {
+     // Continue profiling
+     return false;
+   }
+ }