8370078: Remove unnecessary argument in ContiguousSpace::initialize

Reviewed-by: fandreuzzi, jsikstro

Author: albertnetymk

src/hotspot/share/gc/epsilon/epsilonHeap.cpp

@@ -52,7 +52,7 @@ jint EpsilonHeap::initialize() {
   initialize_reserved_region(heap_rs);
 
   _space = new ContiguousSpace();
-  _space->initialize(committed_region, /* clear_space = */ true, /* mangle_space = */ true);
+  _space->initialize(committed_region, /* clear_space = */ true);
 
   // Precompute hot fields
   _max_tlab_size = MIN2(CollectedHeap::max_tlab_size(), align_object_size(EpsilonMaxTLABSize / HeapWordSize));

src/hotspot/share/gc/serial/defNewGeneration.cpp

@@ -297,9 +297,9 @@ void DefNewGeneration::init_spaces() {
   MemRegion edenMR((HeapWord*)eden_start, (HeapWord*)eden_end);
 
   // Reset the spaces for their new regions.
-  from()->initialize(fromMR, from()->is_empty(), SpaceDecorator::Mangle);
-  to()->initialize(toMR, true, SpaceDecorator::Mangle);
-  eden()->initialize(edenMR, true, SpaceDecorator::Mangle);
+  from()->initialize(fromMR, from()->is_empty());
+  to()->initialize(toMR, true);
+  eden()->initialize(edenMR, true);
 
   post_resize();
 }
@@ -340,7 +340,7 @@ void DefNewGeneration::expand_eden_by(size_t delta_bytes) {
   }
 
   MemRegion eden_mr{eden()->bottom(), (HeapWord*)_virtual_space.high()};
-  eden()->initialize(eden_mr, eden()->is_empty(), SpaceDecorator::Mangle);
+  eden()->initialize(eden_mr, eden()->is_empty());
 
   post_resize();
 }

src/hotspot/share/gc/serial/tenuredGeneration.cpp

@@ -314,7 +314,7 @@ TenuredGeneration::TenuredGeneration(ReservedSpace rs,
   HeapWord* bottom = (HeapWord*) _virtual_space.low();
   HeapWord* end    = (HeapWord*) _virtual_space.high();
   _the_space  = new ContiguousSpace();
-  _the_space->initialize(MemRegion(bottom, end), SpaceDecorator::Clear, SpaceDecorator::Mangle);
+  _the_space->initialize(MemRegion(bottom, end), SpaceDecorator::Clear);
   // If we don't shrink the heap in steps, '_shrink_factor' is always 100%.
   _shrink_factor = ShrinkHeapInSteps ? 0 : 100;
   _capacity_at_prologue = 0;

src/hotspot/share/gc/shared/space.cpp

@@ -44,8 +44,7 @@ ContiguousSpace::ContiguousSpace():
   _top(nullptr) {}
 
 void ContiguousSpace::initialize(MemRegion mr,
-                                 bool clear_space,
-                                 bool mangle_space) {
+                                 bool clear_space) {
   HeapWord* bottom = mr.start();
   HeapWord* end    = mr.end();
   assert(Universe::on_page_boundary(bottom) && Universe::on_page_boundary(end),
@@ -55,7 +54,7 @@ void ContiguousSpace::initialize(MemRegion mr,
   if (clear_space) {
     clear(SpaceDecorator::DontMangle);
   }
-  if (ZapUnusedHeapArea && mangle_space) {
+  if (ZapUnusedHeapArea) {
     mangle_unused_area();
   }
 }

src/hotspot/share/gc/shared/space.hpp

@@ -101,7 +101,7 @@ class ContiguousSpace: public CHeapObj<mtGC> {
   // any purpose.  The "mr" arguments gives the bounds of the space, and
   // the "clear_space" argument should be true unless the memory in "mr" is
   // known to be zeroed.
-  void initialize(MemRegion mr, bool clear_space, bool mangle_space);
+  void initialize(MemRegion mr, bool clear_space);
 
   // The "clear" method must be called on a region that may have
   // had allocation performed in it, but is now to be considered empty.