Merge

make/autoconf/build-aux/config.guess

@@ -29,7 +29,40 @@
 # and fix the broken property, if needed.
 
 DIR=`dirname $0`
-OUT=`. $DIR/autoconf-config.guess`
+OUT=`. $DIR/autoconf-config.guess 2> /dev/null`
+
+# Handle some cases that autoconf-config.guess is not capable of
+if [ "x$OUT" = x ]; then
+  if [ `uname -s` = Linux ]; then
+    # Test and fix little endian MIPS.
+    if [ `uname -m` = mipsel ]; then
+      OUT=mipsel-unknown-linux-gnu
+    elif [ `uname -m` = mips64el ]; then
+      OUT=mips64el-unknown-linux-gnu
+    # Test and fix little endian PowerPC64.
+    elif [ `uname -m` = ppc64le ]; then
+      OUT=powerpc64le-unknown-linux-gnu
+    # Test and fix LoongArch64.
+    elif [ `uname -m` = loongarch64 ]; then
+      OUT=loongarch64-unknown-linux-gnu
+    # Test and fix RISC-V.
+    elif [ `uname -m` = riscv64 ]; then
+      OUT=riscv64-unknown-linux-gnu
+    fi
+  # Test and fix cygwin machine arch .x86_64
+  elif [[ `uname -s` = CYGWIN* ]]; then
+    if [ `uname -m` = ".x86_64" ]; then
+      OUT=x86_64-unknown-cygwin
+    fi
+  fi
+
+  if [ "x$OUT" = x ]; then
+    # Run autoconf-config.guess again to get the error message.
+    . $DIR/autoconf-config.guess > /dev/null
+  else
+    printf "guessed by custom config.guess... " >&2
+  fi
+fi
 
 # Detect C library.
 # Use '-gnu'  suffix on systems that use glibc.
@@ -81,45 +114,6 @@ if test $? = 0; then
   OUT=powerpc$KERNEL_BITMODE`echo $OUT | sed -e 's/[^-]*//'`
 fi
 
-# Test and fix little endian PowerPC64.
-# TODO: should be handled by autoconf-config.guess.
-if [ "x$OUT" = x ]; then
-  if [ `uname -m` = ppc64le ]; then
-    if [ `uname -s` = Linux ]; then
-      OUT=powerpc64le-unknown-linux-gnu
-    fi
-  fi
-fi
-
-# Test and fix little endian MIPS.
-if [ "x$OUT" = x ]; then
-  if [ `uname -s` = Linux ]; then
-    if [ `uname -m` = mipsel ]; then
-      OUT=mipsel-unknown-linux-gnu
-    elif [ `uname -m` = mips64el ]; then
-      OUT=mips64el-unknown-linux-gnu
-    fi
-  fi
-fi
-
-# Test and fix LoongArch64.
-if [ "x$OUT" = x ]; then
-  if [ `uname -s` = Linux ]; then
-    if [ `uname -m` = loongarch64 ]; then
-      OUT=loongarch64-unknown-linux-gnu
-    fi
-  fi
-fi
-
-# Test and fix RISC-V.
-if [ "x$OUT" = x ]; then
-  if [ `uname -s` = Linux ]; then
-    if [ `uname -m` = riscv64 ]; then
-      OUT=riscv64-unknown-linux-gnu
-    fi
-  fi
-fi
-
 # Test and fix cpu on macos-aarch64, uname -p reports arm, buildsys expects aarch64
 echo $OUT | grep arm-apple-darwin > /dev/null 2> /dev/null
 if test $? != 0; then

src/hotspot/share/memory/arena.cpp

@@ -369,6 +369,7 @@ void *Arena::Arealloc(void* old_ptr, size_t old_size, size_t new_size, AllocFail
 
 // Determine if pointer belongs to this Arena or not.
 bool Arena::contains( const void *ptr ) const {
+  if (_chunk == NULL) return false;
   if( (void*)_chunk->bottom() <= ptr && ptr < (void*)_hwm )
     return true;                // Check for in this chunk
   for (Chunk *c = _first; c; c = c->next()) {

src/hotspot/share/opto/bytecodeInfo.cpp

@@ -44,7 +44,7 @@ InlineTree::InlineTree(Compile* c,
                        JVMState* caller_jvms, int caller_bci,
                        int max_inline_level) :
   C(c),
-  _caller_jvms(caller_jvms),
+  _caller_jvms(NULL),
   _method(callee),
   _late_inline(false),
   _caller_tree((InlineTree*) caller_tree),
@@ -57,13 +57,13 @@ InlineTree::InlineTree(Compile* c,
   _count_inlines = 0;
   _forced_inline = false;
 #endif
-  if (_caller_jvms != NULL) {
+  if (caller_jvms != NULL) {
     // Keep a private copy of the caller_jvms:
     _caller_jvms = new (C) JVMState(caller_jvms->method(), caller_tree->caller_jvms());
     _caller_jvms->set_bci(caller_jvms->bci());
     assert(!caller_jvms->should_reexecute(), "there should be no reexecute bytecode with inlining");
+    assert(_caller_jvms->same_calls_as(caller_jvms), "consistent JVMS");
   }
-  assert(_caller_jvms->same_calls_as(caller_jvms), "consistent JVMS");
   assert((caller_tree == NULL ? 0 : caller_tree->stack_depth() + 1) == stack_depth(), "correct (redundant) depth parameter");
   assert(caller_bci == this->caller_bci(), "correct (redundant) bci parameter");
   // Update hierarchical counts, count_inline_bcs() and count_inlines()

src/hotspot/share/opto/chaitin.hpp

@@ -731,8 +731,8 @@ private:
   int yank_if_dead_recurse(Node *old, Node *orig_old, Block *current_block,
       Node_List *value, Node_List *regnd);
   int yank( Node *old, Block *current_block, Node_List *value, Node_List *regnd );
-  int elide_copy( Node *n, int k, Block *current_block, Node_List &value, Node_List &regnd, bool can_change_regs );
+  int elide_copy( Node *n, int k, Block *current_block, Node_List *value, Node_List *regnd, bool can_change_regs );
-  int use_prior_register( Node *copy, uint idx, Node *def, Block *current_block, Node_List &value, Node_List &regnd );
+  int use_prior_register( Node *copy, uint idx, Node *def, Block *current_block, Node_List *value, Node_List *regnd );
   bool may_be_copy_of_callee( Node *def ) const;
 
   // If nreg already contains the same constant as val then eliminate it

src/hotspot/share/opto/loopnode.cpp

@@ -2547,7 +2547,8 @@ SafePointNode* CountedLoopNode::outer_safepoint() const {
 
 Node* CountedLoopNode::skip_predicates_from_entry(Node* ctrl) {
     while (ctrl != NULL && ctrl->is_Proj() && ctrl->in(0) != NULL && ctrl->in(0)->is_If() &&
-            (ctrl->in(0)->as_If()->proj_out_or_null(1-ctrl->as_Proj()->_con) == NULL ||
+           !is_zero_trip_guard_if(ctrl->in(0)->as_If()) &&
+           (ctrl->in(0)->as_If()->proj_out_or_null(1-ctrl->as_Proj()->_con) == NULL ||
              (ctrl->in(0)->as_If()->proj_out(1-ctrl->as_Proj()->_con)->outcnt() == 1 &&
               ctrl->in(0)->as_If()->proj_out(1-ctrl->as_Proj()->_con)->unique_out()->Opcode() == Op_Halt))) {
       ctrl = ctrl->in(0)->in(0);
@@ -2556,6 +2557,22 @@ Node* CountedLoopNode::skip_predicates_from_entry(Node* ctrl) {
     return ctrl;
   }
 
+bool CountedLoopNode::is_zero_trip_guard_if(const IfNode* iff) {
+  if (iff->in(1) == NULL || !iff->in(1)->is_Bool()) {
+    return false;
+  }
+  if (iff->in(1)->in(1) == NULL || iff->in(1)->in(1)->Opcode() != Op_CmpI) {
+    return false;
+  }
+  if (iff->in(1)->in(1)->in(1) != NULL && iff->in(1)->in(1)->in(1)->Opcode() == Op_OpaqueZeroTripGuard) {
+    return true;
+  }
+  if (iff->in(1)->in(1)->in(2) != NULL && iff->in(1)->in(1)->in(2)->Opcode() == Op_OpaqueZeroTripGuard) {
+    return true;
+  }
+  return false;
+}
+
 Node* CountedLoopNode::skip_predicates() {
   Node* ctrl = in(LoopNode::EntryControl);
   if (is_main_loop()) {
@@ -5436,7 +5453,7 @@ Node* CountedLoopNode::is_canonical_loop_entry() {
     return NULL;
   }
   Node* iffm = ctrl->in(0);
-  if (iffm == NULL || !iffm->is_If()) {
+  if (iffm == NULL || iffm->Opcode() != Op_If) {
     return NULL;
   }
   Node* bolzm = iffm->in(1);

src/hotspot/share/opto/loopnode.hpp

@@ -355,6 +355,8 @@ public:
 #ifndef PRODUCT
   virtual void dump_spec(outputStream *st) const;
 #endif
+
+  static bool is_zero_trip_guard_if(const IfNode* iff);
 };
 
 class LongCountedLoopNode : public BaseCountedLoopNode {

src/hotspot/share/opto/postaloc.cpp

@@ -30,7 +30,7 @@
 
 // See if this register (or pairs, or vector) already contains the value.
 static bool register_contains_value(Node* val, OptoReg::Name reg, int n_regs,
-                                    Node_List& value) {
+                                    const Node_List &value) {
   for (int i = 0; i < n_regs; i++) {
     OptoReg::Name nreg = OptoReg::add(reg,-i);
     if (value[nreg] != val)
@@ -77,7 +77,7 @@ bool PhaseChaitin::may_be_copy_of_callee( Node *def ) const {
 
 //------------------------------yank-----------------------------------
 // Helper function for yank_if_dead
-int PhaseChaitin::yank( Node *old, Block *current_block, Node_List *value, Node_List *regnd ) {
+int PhaseChaitin::yank(Node *old, Block *current_block, Node_List *value, Node_List *regnd) {
   int blk_adjust=0;
   Block *oldb = _cfg.get_block_for_node(old);
   oldb->find_remove(old);
@@ -87,9 +87,10 @@ int PhaseChaitin::yank( Node *old, Block *current_block, Node_List *value, Node_
   }
   _cfg.unmap_node_from_block(old);
   OptoReg::Name old_reg = lrgs(_lrg_map.live_range_id(old)).reg();
-  if( regnd && (*regnd)[old_reg]==old ) { // Instruction is currently available?
+  assert(value != NULL || regnd == NULL, "sanity");
-    value->map(old_reg,NULL);  // Yank from value/regnd maps
+  if (value != NULL && regnd != NULL && regnd->at(old_reg) == old) { // Instruction is currently available?
-    regnd->map(old_reg,NULL);  // This register's value is now unknown
+    value->map(old_reg, NULL); // Yank from value/regnd maps
+    regnd->map(old_reg, NULL); // This register's value is now unknown
   }
   return blk_adjust;
 }
@@ -161,7 +162,7 @@ int PhaseChaitin::yank_if_dead_recurse(Node *old, Node *orig_old, Block *current
 // Use the prior value instead of the current value, in an effort to make
 // the current value go dead.  Return block iterator adjustment, in case
 // we yank some instructions from this block.
-int PhaseChaitin::use_prior_register( Node *n, uint idx, Node *def, Block *current_block, Node_List &value, Node_List &regnd ) {
+int PhaseChaitin::use_prior_register( Node *n, uint idx, Node *def, Block *current_block, Node_List *value, Node_List *regnd ) {
   // No effect?
   if( def == n->in(idx) ) return 0;
   // Def is currently dead and can be removed?  Do not resurrect
@@ -207,7 +208,7 @@ int PhaseChaitin::use_prior_register( Node *n, uint idx, Node *def, Block *curre
   _post_alloc++;
 
   // Is old def now dead?  We successfully yanked a copy?
-  return yank_if_dead(old,current_block,&value,&regnd);
+  return yank_if_dead(old,current_block,value,regnd);
 }
 
 
@@ -229,7 +230,7 @@ Node *PhaseChaitin::skip_copies( Node *c ) {
 
 //------------------------------elide_copy-------------------------------------
 // Remove (bypass) copies along Node n, edge k.
-int PhaseChaitin::elide_copy( Node *n, int k, Block *current_block, Node_List &value, Node_List &regnd, bool can_change_regs ) {
+int PhaseChaitin::elide_copy( Node *n, int k, Block *current_block, Node_List *value, Node_List *regnd, bool can_change_regs ) {
   int blk_adjust = 0;
 
   uint nk_idx = _lrg_map.live_range_id(n->in(k));
@@ -253,11 +254,14 @@ int PhaseChaitin::elide_copy( Node *n, int k, Block *current_block, Node_List &v
 
   // Phis and 2-address instructions cannot change registers so easily - their
   // outputs must match their input.
-  if( !can_change_regs )
+  if (!can_change_regs) {
     return blk_adjust;          // Only check stupid copies!
-
+  }
   // Loop backedges won't have a value-mapping yet
-  if( &value == NULL ) return blk_adjust;
+  assert(regnd != NULL || value == NULL, "sanity");
+  if (value == NULL || regnd == NULL) {
+    return blk_adjust;
+  }
 
   // Skip through all copies to the _value_ being used.  Do not change from
   // int to pointer.  This attempts to jump through a chain of copies, where
@@ -273,10 +277,11 @@ int PhaseChaitin::elide_copy( Node *n, int k, Block *current_block, Node_List &v
   // See if it happens to already be in the correct register!
   // (either Phi's direct register, or the common case of the name
   // never-clobbered original-def register)
-  if (register_contains_value(val, val_reg, n_regs, value)) {
+  if (register_contains_value(val, val_reg, n_regs, *value)) {
-    blk_adjust += use_prior_register(n,k,regnd[val_reg],current_block,value,regnd);
+    blk_adjust += use_prior_register(n,k,regnd->at(val_reg),current_block,value,regnd);
-    if( n->in(k) == regnd[val_reg] ) // Success!  Quit trying
+    if (n->in(k) == regnd->at(val_reg)) {
-      return blk_adjust;
+      return blk_adjust; // Success!  Quit trying
+    }
   }
 
   // See if we can skip the copy by changing registers.  Don't change from
@@ -304,7 +309,7 @@ int PhaseChaitin::elide_copy( Node *n, int k, Block *current_block, Node_List &v
       if (ignore_self) continue;
     }
 
-    Node *vv = value[reg];
+    Node *vv = value->at(reg);
     // For scalable register, number of registers may be inconsistent between
     // "val_reg" and "reg". For example, when "val" resides in register
     // but "reg" is located in stack.
@@ -325,7 +330,7 @@ int PhaseChaitin::elide_copy( Node *n, int k, Block *current_block, Node_List &v
         last = (n_regs-1); // Looking for the last part of a set
       }
       if ((reg&last) != last) continue; // Wrong part of a set
-      if (!register_contains_value(vv, reg, n_regs, value)) continue; // Different value
+      if (!register_contains_value(vv, reg, n_regs, *value)) continue; // Different value
     }
     if( vv == val ||            // Got a direct hit?
         (t && vv && vv->bottom_type() == t && vv->is_Mach() &&
@@ -333,9 +338,9 @@ int PhaseChaitin::elide_copy( Node *n, int k, Block *current_block, Node_List &v
       assert( !n->is_Phi(), "cannot change registers at a Phi so easily" );
       if( OptoReg::is_stack(nk_reg) || // CISC-loading from stack OR
           OptoReg::is_reg(reg) || // turning into a register use OR
-          regnd[reg]->outcnt()==1 ) { // last use of a spill-load turns into a CISC use
+          regnd->at(reg)->outcnt()==1 ) { // last use of a spill-load turns into a CISC use
-        blk_adjust += use_prior_register(n,k,regnd[reg],current_block,value,regnd);
+        blk_adjust += use_prior_register(n,k,regnd->at(reg),current_block,value,regnd);
-        if( n->in(k) == regnd[reg] ) // Success!  Quit trying
+        if( n->in(k) == regnd->at(reg) ) // Success!  Quit trying
           return blk_adjust;
       } // End of if not degrading to a stack
     } // End of if found value in another register
@@ -535,7 +540,7 @@ void PhaseChaitin::post_allocate_copy_removal() {
       Block* pb = _cfg.get_block_for_node(block->pred(j));
       // Remove copies along phi edges
       for (uint k = 1; k < phi_dex; k++) {
-        elide_copy(block->get_node(k), j, block, *blk2value[pb->_pre_order], *blk2regnd[pb->_pre_order], false);
+        elide_copy(block->get_node(k), j, block, blk2value[pb->_pre_order], blk2regnd[pb->_pre_order], false);
       }
       if (blk2value[pb->_pre_order]) { // Have a mapping on this edge?
         // See if this predecessor's mappings have been used by everybody
@@ -691,7 +696,7 @@ void PhaseChaitin::post_allocate_copy_removal() {
 
       // Remove copies along input edges
       for (k = 1; k < n->req(); k++) {
-        j -= elide_copy(n, k, block, value, regnd, two_adr != k);
+        j -= elide_copy(n, k, block, &value, &regnd, two_adr != k);
       }
 
       // Unallocated Nodes define no registers

src/hotspot/share/runtime/vmStructs.hpp

@@ -188,13 +188,18 @@ private:
 #ifdef ASSERT
 
 // This macro checks the type of a VMStructEntry by comparing pointer types
-#define CHECK_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type)                 \
+#define CHECK_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type) { \
- {typeName *dummyObj = NULL; type* dummy = &dummyObj->fieldName;                   \
+  static_assert( \
-  assert(offset_of(typeName, fieldName) < sizeof(typeName), "Illegal nonstatic struct entry, field offset too large"); }
+    std::is_convertible< \
+      std::add_pointer_t<decltype(declval<typeName>().fieldName)>, \
+      std::add_pointer_t<type>>::value, \
+    "type mismatch for " XSTR(fieldName) " member of " XSTR(typeName)); \
+  assert(offset_of(typeName, fieldName) < sizeof(typeName), "..."); \
+}
 
 // This macro checks the type of a volatile VMStructEntry by comparing pointer types
-#define CHECK_VOLATILE_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type)        \
+#define CHECK_VOLATILE_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type) \
- {typedef type dummyvtype; typeName *dummyObj = NULL; volatile dummyvtype* dummy = &dummyObj->fieldName; }
+  CHECK_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, std::add_volatile_t<type>)
 
 // This macro checks the type of a static VMStructEntry by comparing pointer types
 #define CHECK_STATIC_VM_STRUCT_ENTRY(typeName, fieldName, type)                    \

src/hotspot/share/utilities/globalDefinitions.hpp

@@ -35,6 +35,7 @@
 #include COMPILER_HEADER(utilities/globalDefinitions)
 
 #include <cstddef>
+#include <type_traits>
 
 class oopDesc;
 
@@ -1288,4 +1289,8 @@ template<typename K> bool primitive_equals(const K& k0, const K& k1) {
 // Allow use of C++ thread_local when approved - see JDK-8282469.
 #define APPROVED_CPP_THREAD_LOCAL thread_local
 
+// Converts any type T to a reference type.
+template<typename T>
+std::add_rvalue_reference_t<T> declval() noexcept;
+
 #endif // SHARE_UTILITIES_GLOBALDEFINITIONS_HPP

src/hotspot/share/utilities/globalDefinitions_gcc.hpp

@@ -139,10 +139,21 @@ inline int g_isfinite(jdouble f)                 { return isfinite(f); }
 #endif // _LP64
 
 // gcc warns about applying offsetof() to non-POD object or calculating
-// offset directly when base address is NULL. Use 16 to get around the
+// offset directly when base address is NULL. The -Wno-invalid-offsetof
-// warning. The -Wno-invalid-offsetof option could be used to suppress
+// option could be used to suppress this warning, but we instead just
-// this warning, but we instead just avoid the use of offsetof().
+// avoid the use of offsetof().
-#define offset_of(klass,field) (size_t)((intx)&(((klass*)16)->field) - 16)
+//
+// FIXME: This macro is complex and rather arcane. Perhaps we should
+// use offsetof() instead, with the invalid-offsetof warning
+// temporarily disabled.
+#define offset_of(klass,field)                          \
+[]() {                                                  \
+  char space[sizeof (klass)] ATTRIBUTE_ALIGNED(16);     \
+  klass* dummyObj = (klass*)space;                      \
+  char* c = (char*)(void*)&dummyObj->field;             \
+  return (size_t)(c - space);                           \
+}()
+
 
 #if defined(_LP64) && defined(__APPLE__)
 #define JLONG_FORMAT          "%ld"

src/java.compiler/share/classes/javax/lang/model/util/Elements.java

@@ -622,6 +622,8 @@ public interface Elements {
      * overrides another method.
      * When a non-abstract method overrides an abstract one, the
      * former is also said to <i>implement</i> the latter.
+     * As implied by JLS {@jls 8.4.8.1}, a method does <em>not</em>
+     * override itself. The overrides relation is <i>irreflexive</i>.
      *
      * <p> In the simplest and most typical usage, the value of the
      * {@code type} parameter will simply be the class or interface

src/jdk.compiler/share/classes/com/sun/source/doctree/DocTree.java

@@ -227,7 +227,7 @@ public interface DocTree {
         SPEC("spec"),
 
         /**
-         * Used for instances of {@link EndElementTree}
+         * Used for instances of {@link StartElementTree}
          * representing the start of an HTML element.
          */
         START_ELEMENT,

src/jdk.jshell/share/classes/jdk/jshell/execution/JdiDefaultExecutionControl.java

@@ -48,6 +48,7 @@ import com.sun.jdi.StackFrame;
 import com.sun.jdi.ThreadReference;
 import com.sun.jdi.VMDisconnectedException;
 import com.sun.jdi.VirtualMachine;
+import java.util.stream.Stream;
 import jdk.jshell.spi.ExecutionControl;
 import jdk.jshell.spi.ExecutionEnv;
 import static jdk.jshell.execution.Util.remoteInputOutput;
@@ -96,10 +97,15 @@ public class JdiDefaultExecutionControl extends JdiExecutionControl {
             // timeout on I/O-socket
             listener.setSoTimeout(timeout);
             int port = listener.getLocalPort();
+            List<String> augmentedremoteVMOptions =
+                    Stream.concat(env.extraRemoteVMOptions().stream(),
+                                  //disable System.console():
+                                  List.of("-Djdk.console=java.base").stream())
+                          .toList();
 
             // Set-up the JDI connection
             JdiInitiator jdii = new JdiInitiator(port,
-                    env.extraRemoteVMOptions(), remoteAgent, isLaunch, host,
+                    augmentedremoteVMOptions, remoteAgent, isLaunch, host,
                     timeout, Collections.emptyMap());
             VirtualMachine vm = jdii.vm();
             Process process = jdii.process();

src/jdk.management.jfr/share/classes/jdk/management/jfr/DiskRepository.java

@@ -139,7 +139,7 @@ final class DiskRepository implements Closeable {
     private long typeId;
     private int typeIdshift;
     private int sizeShift;
-    private int payLoadSize;
+    private long payLoadSize;
     private int longValueshift;
     private int eventFieldSize;
     private int lastFlush;
@@ -225,7 +225,7 @@ final class DiskRepository implements Closeable {
     private void processEvent() {
         int left = currentByteArray.length - index;
         if (left >= payLoadSize) {
-            index += payLoadSize;
+            index = index + (int)payLoadSize;
             payLoadSize = 0;
             state = State.EVENT_SIZE;
         } else {
@@ -261,7 +261,7 @@ final class DiskRepository implements Closeable {
 
         eventFieldSize++;
         byte b = nextByte(false);
-        int v = (b & 0x7F);
+        long v = (b & 0x7F);
         payLoadSize += (v << sizeShift);
         if (b >= 0) {
             if (payLoadSize == 0) {

test/hotspot/jtreg/ProblemList.txt

@@ -79,7 +79,6 @@ gc/stress/gclocker/TestGCLockerWithParallel.java 8180622 generic-all
 gc/stress/gclocker/TestGCLockerWithG1.java 8180622 generic-all
 gc/stress/TestJNIBlockFullGC/TestJNIBlockFullGC.java 8192647 generic-all
 gc/stress/TestStressG1Humongous.java 8286554 windows-x64
-gc/TestFullGCCount.java 8298296 linux-x64
 
 #############################################################################
 

test/hotspot/jtreg/gc/TestFullGCCount.java

@@ -29,6 +29,8 @@ package gc;
  * @summary JMM GC counters overcount in some cases
  * @comment Shenandoah has "ExplicitGCInvokesConcurrent" on by default
  * @requires !(vm.gc == "Shenandoah" & vm.opt.ExplicitGCInvokesConcurrent != false)
+ * @comment G1 has separate counters for STW Full GC and concurrent GC.
+ * @requires !(vm.gc == "G1" & vm.opt.ExplicitGCInvokesConcurrent)
  * @requires vm.gc != "Z"
  * @modules java.management
  * @run main/othervm -Xlog:gc gc.TestFullGCCount

test/langtools/jdk/jshell/ConsoleTest.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8298425
+ * @summary Verify behavior of System.console()
+ * @build KullaTesting TestingInputStream
+ * @run testng ConsoleTest
+ */
+
+
+import org.testng.annotations.Test;
+
+public class ConsoleTest extends KullaTesting {
+
+    @Test
+    public void testConsole1() {
+        assertEval("System.console()", "null");
+    }
+
+}