src/java.base/share/classes/java/lang/invoke/LambdaForm.java

rev 11011 : 8063137: Never-taken branches should be pruned when GWT LambdaForms are shared
Reviewed-by: ?

*** 118,127 ****
--- 118,128 ----
   */
  class LambdaForm {
      final int arity;
      final int result;
      final boolean forceInline;
+     final boolean isGWT;
      @Stable final Name[] names;
      final String debugName;
      MemberName vmentry;   // low-level behavior, or null if not yet prepared
      private boolean isCompiled;
  
*** 242,285 ****
          }
      }
  
      LambdaForm(String debugName,
                 int arity, Name[] names, int result) {
!         this(debugName, arity, names, result, true);
      }
      LambdaForm(String debugName,
!                int arity, Name[] names, int result, boolean forceInline) {
          assert(namesOK(arity, names));
          this.arity = arity;
          this.result = fixResult(result, names);
          this.names = names.clone();
          this.debugName = fixDebugName(debugName);
          this.forceInline = forceInline;
          int maxOutArity = normalize();
          if (maxOutArity > MethodType.MAX_MH_INVOKER_ARITY) {
              // Cannot use LF interpreter on very high arity expressions.
              assert(maxOutArity <= MethodType.MAX_JVM_ARITY);
              compileToBytecode();
          }
      }
      LambdaForm(String debugName,
                 int arity, Name[] names) {
!         this(debugName, arity, names, LAST_RESULT, true);
      }
      LambdaForm(String debugName,
!                int arity, Name[] names, boolean forceInline) {
!         this(debugName, arity, names, LAST_RESULT, forceInline);
      }
      LambdaForm(String debugName,
                 Name[] formals, Name[] temps, Name result) {
          this(debugName,
!              formals.length, buildNames(formals, temps, result), LAST_RESULT, true);
      }
      LambdaForm(String debugName,
                 Name[] formals, Name[] temps, Name result, boolean forceInline) {
          this(debugName,
!              formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline);
      }
  
      private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
          int arity = formals.length;
          int length = arity + temps.length + (result == null ? 0 : 1);
--- 243,291 ----
          }
      }
  
      LambdaForm(String debugName,
                 int arity, Name[] names, int result) {
!         this(debugName, arity, names, result, /*forceInline=*/true, /*isGWT=*/false);
      }
      LambdaForm(String debugName,
!                int arity, Name[] names, int result, boolean forceInline, boolean isGWT) {
          assert(namesOK(arity, names));
          this.arity = arity;
          this.result = fixResult(result, names);
          this.names = names.clone();
          this.debugName = fixDebugName(debugName);
          this.forceInline = forceInline;
+         this.isGWT = isGWT;
          int maxOutArity = normalize();
          if (maxOutArity > MethodType.MAX_MH_INVOKER_ARITY) {
              // Cannot use LF interpreter on very high arity expressions.
              assert(maxOutArity <= MethodType.MAX_JVM_ARITY);
              compileToBytecode();
          }
      }
      LambdaForm(String debugName,
                 int arity, Name[] names) {
!         this(debugName, arity, names, LAST_RESULT, /*forceInline=*/true, /*isGWT=*/false);
      }
      LambdaForm(String debugName,
!                int arity, Name[] names, boolean forceInline, boolean isGWT) {
!         this(debugName, arity, names, LAST_RESULT, forceInline, isGWT);
      }
      LambdaForm(String debugName,
                 Name[] formals, Name[] temps, Name result) {
          this(debugName,
!              formals.length, buildNames(formals, temps, result), LAST_RESULT, /*forceInline=*/true, /*isGWT=*/false);
      }
      LambdaForm(String debugName,
                 Name[] formals, Name[] temps, Name result, boolean forceInline) {
          this(debugName,
!              formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline, /*isGWT=*/false);
!     }
! 
!     static LambdaForm makeGuardWithTestForm(int paramCount, Name[] names) {
!         return new LambdaForm("guard", paramCount, names, /*forceInline=*/true, /*isGWT=*/true);
      }
  
      private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
          int arity = formals.length;
          int length = arity + temps.length + (result == null ? 0 : 1);
*** 289,311 ****
              names[length - 1] = result;
          return names;
      }
  
      private LambdaForm(String sig) {
-         this(sig, true);
-     }
- 
-     private LambdaForm(String sig, boolean forceInline) {
          // Make a blank lambda form, which returns a constant zero or null.
          // It is used as a template for managing the invocation of similar forms that are non-empty.
          // Called only from getPreparedForm.
          assert(isValidSignature(sig));
          this.arity = signatureArity(sig);
          this.result = (signatureReturn(sig) == V_TYPE ? -1 : arity);
          this.names = buildEmptyNames(arity, sig);
          this.debugName = "LF.zero";
!         this.forceInline = forceInline;
          assert(nameRefsAreLegal());
          assert(isEmpty());
          assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature();
      }
  
--- 295,314 ----
              names[length - 1] = result;
          return names;
      }
  
      private LambdaForm(String sig) {
          // Make a blank lambda form, which returns a constant zero or null.
          // It is used as a template for managing the invocation of similar forms that are non-empty.
          // Called only from getPreparedForm.
          assert(isValidSignature(sig));
          this.arity = signatureArity(sig);
          this.result = (signatureReturn(sig) == V_TYPE ? -1 : arity);
          this.names = buildEmptyNames(arity, sig);
          this.debugName = "LF.zero";
!         this.forceInline = true;
!         this.isGWT = false;
          assert(nameRefsAreLegal());
          assert(isEmpty());
          assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature();
      }
  
*** 1793,1802 ****
--- 1796,1814 ----
      @Target(ElementType.METHOD)
      @Retention(RetentionPolicy.RUNTIME)
      @interface Hidden {
      }
  
+     /**
+      * Internal marker which signals JIT that gathered profile is useless.
+      */
+     /*non-public*/
+     @Target(ElementType.METHOD)
+     @Retention(RetentionPolicy.RUNTIME)
+     @interface IgnoreProfile {
+     }
+ 
      private static final HashMap<String,Integer> DEBUG_NAME_COUNTERS;
      static {
          if (debugEnabled())
              DEBUG_NAME_COUNTERS = new HashMap<>();
          else