src/share/vm/runtime/commandLineFlagConstraintsCompiler.cpp

*** 116,131 ****
  
    return Flag::SUCCESS;
  }
  
  Flag::Error AllocatePrefetchStepSizeConstraintFunc(intx value, bool verbose) {
!   if (value < 1 || value > max_jint) {
      CommandLineError::print(verbose,
                              "AllocatePrefetchStepSize (" INTX_FORMAT ") "
                              "must be between 1 and %d\n",
                              AllocatePrefetchStepSize,
!                             max_jint);
      return Flag::VIOLATES_CONSTRAINT;
    }
  
    if (AllocatePrefetchDistance % AllocatePrefetchStepSize != 0) {
       CommandLineError::print(verbose,
--- 116,132 ----
  
    return Flag::SUCCESS;
  }
  
  Flag::Error AllocatePrefetchStepSizeConstraintFunc(intx value, bool verbose) {
!   intx max_value = 512;
!   if (value < 1 || value > max_value) {
      CommandLineError::print(verbose,
                              "AllocatePrefetchStepSize (" INTX_FORMAT ") "
                              "must be between 1 and %d\n",
                              AllocatePrefetchStepSize,
!                             max_value);
      return Flag::VIOLATES_CONSTRAINT;
    }
  
    if (AllocatePrefetchDistance % AllocatePrefetchStepSize != 0) {
      CommandLineError::print(verbose,
*** 136,145 ****
--- 137,164 ----
                              AllocatePrefetchDistance, AllocatePrefetchStepSize,
                              AllocatePrefetchDistance % AllocatePrefetchStepSize);
      return Flag::VIOLATES_CONSTRAINT;
    }
  
+   /* The limit of 64 for the quotient of AllocatePrefetchDistance and AllocatePrefetchSize
+    * originates from the limit of 64 for AllocatePrefetchLines/AllocateInstancePrefetchLines.
+    * If AllocatePrefetchStyle == 2, the quotient from above is used in PhaseMacroExpand::prefetch_allocation()
+    * to determine the number of lines to prefetch. For other values of AllocatePrefetchStyle,
+    * AllocatePrefetchDistance and AllocatePrefetchSize is used. For consistency, all these
+    * quantities must have the same limit (64 in this case).
+    */
+   if (AllocatePrefetchDistance / AllocatePrefetchStepSize > 64) {
+     CommandLineError::print(verbose,
+                             "AllocatePrefetchDistance (" INTX_FORMAT ") too large or "
+                             "AllocatePrefetchStepSize (" INTX_FORMAT ") too small; "
+                             "try decreasing/increasing values so that "
+                             "AllocatePrefetchDistance / AllocatePrefetchStepSize <= 64\n",
+                             AllocatePrefetchDistance, AllocatePrefetchStepSize,
+                             AllocatePrefetchDistance % AllocatePrefetchStepSize);
+     return Flag::VIOLATES_CONSTRAINT;
+   }
+ 
    return Flag::SUCCESS;
  }
  
  Flag::Error CompileThresholdConstraintFunc(intx value, bool verbose) {
    if (value < 0 || value > INT_MAX >> InvocationCounter::count_shift) {