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

rev 11254 : 8063137: Never-taken branches should be pruned when GWT LambdaForms are shared
Reviewed-by: ?
rev 11255 : [mq]: gwt.profile.1
rev 11258 : 8069591: Customize LambdaForms which are invoked using MH.invoke/invokeExact
Reviewed-by: ?

*** 118,127 ****
--- 118,128 ----
   */
  class LambdaForm {
      final int arity;
      final int result;
      final boolean forceInline;
+     final MethodHandle customized;
      @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, /*forceInline=*/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, /*forceInline=*/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, /*forceInline=*/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);
--- 243,287 ----
          }
      }
  
      LambdaForm(String debugName,
                 int arity, Name[] names, int result) {
!         this(debugName, arity, names, result, /*forceInline=*/true, /*customized=*/null);
      }
      LambdaForm(String debugName,
!                int arity, Name[] names, int result, boolean forceInline, MethodHandle customized) {
          assert(namesOK(arity, names));
          this.arity = arity;
          this.result = fixResult(result, names);
          this.names = names.clone();
          this.debugName = fixDebugName(debugName);
          this.forceInline = forceInline;
+         this.customized = customized;
          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, /*customized=*/null);
      }
      LambdaForm(String debugName,
                 int arity, Name[] names, boolean forceInline) {
!         this(debugName, arity, names, LAST_RESULT, forceInline, /*customized=*/null);
      }
      LambdaForm(String debugName,
                 Name[] formals, Name[] temps, Name result) {
          this(debugName,
!              formals.length, buildNames(formals, temps, result), LAST_RESULT, /*forceInline=*/true, /*customized=*/null);
      }
      LambdaForm(String debugName,
                 Name[] formals, Name[] temps, Name result, boolean forceInline) {
          this(debugName,
!              formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline, /*customized=*/null);
      }
  
      private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
          int arity = formals.length;
          int length = arity + temps.length + (result == null ? 0 : 1);
*** 298,307 ****
--- 300,310 ----
          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.customized = null;
          assert(nameRefsAreLegal());
          assert(isEmpty());
          assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature();
      }
  
*** 369,378 ****
--- 372,402 ----
                  assert(!n.isParam()) : n + " is param at " + i;
          }
          return true;
      }
  
+     LambdaForm customize(MethodHandle mh) {
+         LambdaForm customForm = new LambdaForm(debugName, arity, names, result, forceInline, mh);
+         if (COMPILE_THRESHOLD > 0 && isCompiled) {
+             // If shared LambdaForm has been compiled, compile customized version as well.
+             customForm.compileToBytecode();
+         }
+         return customForm;
+     }
+ 
+     LambdaForm uncustomize() {
+         if (customized == null) {
+             return this;
+         }
+         LambdaForm uncustomizedForm  = new LambdaForm(debugName, arity, names, result, forceInline, null);
+         if (COMPILE_THRESHOLD > 0 && isCompiled) {
+             // If customized LambdaForm has been compiled, compile uncustomized version as well.
+             uncustomizedForm.compileToBytecode();
+         }
+         return uncustomizedForm;
+     }
+ 
      /** Renumber and/or replace params so that they are interned and canonically numbered.
       *  @return maximum argument list length among the names (since we have to pass over them anyway)
       */
      private int normalize() {
          Name[] oldNames = null;
*** 411,422 ****
          }
          if (needIntern) {
              for (int i = arity; i < names.length; i++) {
                  names[i].internArguments();
              }
-             assert(nameRefsAreLegal());
          }
          return maxOutArity;
      }
  
      /**
       * Check that all embedded Name references are localizable to this lambda,
--- 435,446 ----
          }
          if (needIntern) {
              for (int i = arity; i < names.length; i++) {
                  names[i].internArguments();
              }
          }
+         assert(nameRefsAreLegal());
          return maxOutArity;
      }
  
      /**
       * Check that all embedded Name references are localizable to this lambda,