SAP · RealCLanger · Jul 20, 2026 · Jul 9, 2026 · Jul 9, 2026 · Jul 9, 2026
diff --git a/make/autoconf/flags-ldflags.m4 b/make/autoconf/flags-ldflags.m4
@@ -81,6 +81,7 @@ AC_DEFUN([FLAGS_SETUP_LDFLAGS_HELPER],
       fi
 
       if test "x$ENABLE_LINKTIME_GC" = xtrue; then
+        BASIC_LDFLAGS_JVM_ONLY="$BASIC_LDFLAGS_JVM_ONLY -Wl,--gc-sections -Wl,--undefined=_ZTV8Metadata"
         BASIC_LDFLAGS_JDK_ONLY="$BASIC_LDFLAGS_JDK_ONLY -Wl,--gc-sections"
       fi
     fi

diff --git a/make/jdk/src/classes/build/tools/cldrconverter/ResourceBundleGenerator.java b/make/jdk/src/classes/build/tools/cldrconverter/ResourceBundleGenerator.java
@@ -29,6 +29,7 @@
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.Arrays;
+import java.util.Comparator;
 import java.util.Formatter;
 import java.util.HashSet;
 import java.util.HashMap;
@@ -39,6 +40,7 @@
 import java.util.Set;
 import java.util.SortedSet;
 import java.util.stream.Collectors;
+import static java.util.ResourceBundle.Control;
 
 class ResourceBundleGenerator implements BundleGenerator {
     // preferred timezones - keeping compatibility with JDK1.1 3 letter abbreviations
@@ -69,6 +71,9 @@ class ResourceBundleGenerator implements BundleGenerator {
     // For duplicated values
     private static final String META_VALUE_PREFIX = "metaValue_";
 
+    // locales in the base module
+    private final Set<Locale> baseModuleLocales = new HashSet<>();
+
     @Override
     public void generateBundle(String packageName, String baseName, String localeID,
                                Map<String, ?> map, BundleType type) throws IOException {
@@ -80,8 +85,15 @@ public void generateBundle(String packageName, String baseName, String localeID,
             return;
         }
 
-        // Assume that non-base resources go into jdk.localedata
-        if (!CLDRConverter.isBaseModule) {
+        if (CLDRConverter.isBaseModule) {
+            if (!localeID.equals("root")) {
+                baseModuleLocales.addAll(
+                    Control.getControl(Control.FORMAT_DEFAULT)
+                        .getCandidateLocales("",
+                            Locale.forLanguageTag(CLDRConverter.toLanguageTag(localeID))));
+            }
+        } else {
+            // Assume that non-base resources go into jdk.localedata
             dirName = dirName + File.separator + "ext";
             packageName = packageName + ".ext";
         }
@@ -284,6 +296,7 @@ public void generateMetaInfo(Map<String, SortedSet<String>> metaInfo) throws IOE
                 import java.util.HashMap;
                 import java.util.Locale;
                 import java.util.Map;
+                import java.util.Set;
                 import sun.util.locale.provider.LocaleDataMetaInfo;
                 import sun.util.locale.provider.LocaleProviderAdapter;
 
@@ -296,6 +309,7 @@ public class %s implements LocaleDataMetaInfo {
                 out.printf("""
                         private static final Map<Locale, String[]> parentLocalesMap = HashMap.newHashMap(%d);
                         private static final Map<String, String> languageAliasMap = HashMap.newHashMap(%d);
+                        private static final Set<Locale> baseModuleLocales;
                         static final boolean nonlikelyScript = %s; // package access from CLDRLocaleProviderAdapter
 
                         static {
@@ -322,7 +336,23 @@ public class %s implements LocaleDataMetaInfo {
                 CLDRConverter.handlerSupplMeta.getLanguageAliasData().forEach((key, value) -> {
                     out.printf("        languageAliasMap.put(\"%s\", \"%s\");\n", CLDRConverter.escape(key), CLDRConverter.escape(value));
                 });
-                out.printf("    }\n\n");
+                out.println();
+
+                // for baseModuleLocales
+                out.printf("        baseModuleLocales = Set.of(\n");
+                out.printf("            %s",
+                    baseModuleLocales.stream()
+                        .map(Locale::toLanguageTag)
+                        .sorted(Comparator.comparing(l -> l.equals("und") ? "" : l))
+                        .map(l -> switch(l) {
+                                case "und"   -> "Locale.ROOT";
+                                case "en"    -> "Locale.ENGLISH";
+                                case "en-US" -> "Locale.US";
+                                default      -> "Locale.forLanguageTag(\"" + l + "\")";
+                            })
+                        .collect(Collectors.joining(",\n            ")));
+                out.printf("\n        );");
+                out.println("\n    }\n");
 
                 // end of static initializer block.
 
@@ -391,6 +421,10 @@ public Map<Locale, String[]> parentLocales() {
                         return parentLocalesMap;
                     }
 
+                    public Set<Locale> baseModuleLocales() {
+                        return baseModuleLocales;
+                    }
+
                     // package access from CLDRLocaleProviderAdapter
                     Map<String, String> likelyScriptMap() {
                         return CLDRMapHolder.likelyScriptMap;

diff --git a/src/hotspot/cpu/aarch64/c2_MacroAssembler_aarch64.cpp b/src/hotspot/cpu/aarch64/c2_MacroAssembler_aarch64.cpp
@@ -2728,7 +2728,8 @@ void C2_MacroAssembler::reconstruct_frame_pointer(Register rtmp) {
 void C2_MacroAssembler::select_from_two_vectors_neon(FloatRegister dst, FloatRegister src1,
                                                      FloatRegister src2, FloatRegister index,
                                                      FloatRegister tmp, unsigned vector_length_in_bytes) {
-  assert_different_registers(dst, src1, src2, tmp);
+  assert_different_registers(src2, tmp);
+  assert_different_registers(index, tmp);
   SIMD_Arrangement size = vector_length_in_bytes == 16 ? T16B : T8B;
 
   if (vector_length_in_bytes == 16) {
@@ -2757,7 +2758,8 @@ void C2_MacroAssembler::select_from_two_vectors_sve(FloatRegister dst, FloatRegi
                                                     FloatRegister src2, FloatRegister index,
                                                     FloatRegister tmp, SIMD_RegVariant T,
                                                     unsigned vector_length_in_bytes) {
-  assert_different_registers(dst, src1, src2, index, tmp);
+  assert_different_registers(src2, tmp);
+  assert_different_registers(index, tmp);
 
   if (vector_length_in_bytes == 8) {
     // We need to fit both the source vectors (src1, src2) in a single vector register because the
@@ -2784,7 +2786,8 @@ void C2_MacroAssembler::select_from_two_vectors(FloatRegister dst, FloatRegister
                                                 FloatRegister tmp, BasicType bt,
                                                 unsigned vector_length_in_bytes) {
 
-  assert_different_registers(dst, src1, src2, index, tmp);
+  assert_different_registers(dst, src1, src2, tmp);
+  assert_different_registers(index, tmp);
 
   // The cases that can reach this method are -
   // - UseSVE = 0/1, vector_length_in_bytes = 8 or 16, excluding double and long types

diff --git a/src/hotspot/cpu/aarch64/frame_aarch64.hpp b/src/hotspot/cpu/aarch64/frame_aarch64.hpp
@@ -186,8 +186,6 @@
   // deoptimization support
   void interpreter_frame_set_last_sp(intptr_t* sp);
 
-  static jint interpreter_frame_expression_stack_direction() { return -1; }
-
   // returns the sending frame, without applying any barriers
   inline frame sender_raw(RegisterMap* map) const;
 

diff --git a/src/hotspot/cpu/aarch64/gc/shenandoah/shenandoahBarrierSetAssembler_aarch64.cpp b/src/hotspot/cpu/aarch64/gc/shenandoah/shenandoahBarrierSetAssembler_aarch64.cpp
@@ -420,6 +420,32 @@ void ShenandoahBarrierSetAssembler::try_peek_weak_handle_in_nmethod(MacroAssembl
   __ bind(done);
 }
 
+void ShenandoahBarrierSetAssembler::check_oop(MacroAssembler* masm, Register obj, Register tmp1, Register tmp2, Label& L_error) {
+  // Check if the oop is in the right area of memory
+  __ mov(tmp2, (intptr_t) Universe::verify_oop_mask());
+  __ andr(tmp1, obj, tmp2);
+  __ mov(tmp2, (intptr_t) Universe::verify_oop_bits());
+
+  // Compare tmp1 and tmp2.  We don't use a compare
+  // instruction here because the flags register is live.
+  __ eor(tmp1, tmp1, tmp2);
+  __ cbnz(tmp1, L_error);
+
+  // This routine is sometimes called before applying GC barriers.
+  // With +COH, loading the klass may end up loading forwarding pointer instead.
+  Label L_skip;
+  if (UseCompactObjectHeaders) {
+    Address gc_state(rthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
+    __ ldrb(tmp1, gc_state);
+    __ tbnz(tmp1, ShenandoahHeap::HAS_FORWARDED_BITPOS, L_skip);
+  }
+
+  // Make sure klass is 'reasonable', which is not zero.
+  __ load_narrow_klass(tmp1, obj);
+  __ cbz(tmp1, L_error);
+  __ bind(L_skip);
+}
+
 void ShenandoahBarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators,
                                                                      Register start, Register count, Register scratch) {
   assert(ShenandoahCardBarrier, "Should have been checked by caller");

diff --git a/src/hotspot/cpu/aarch64/gc/shenandoah/shenandoahBarrierSetAssembler_aarch64.hpp b/src/hotspot/cpu/aarch64/gc/shenandoah/shenandoahBarrierSetAssembler_aarch64.hpp
@@ -74,6 +74,7 @@ class ShenandoahBarrierSetAssembler: public BarrierSetAssembler {
                                              Register obj, Register tmp, Label& slowpath);
   virtual void try_peek_weak_handle_in_nmethod(MacroAssembler* masm, Register weak_handle, Register obj,
                                                Register tmp, Label& slow_path);
+  virtual void check_oop(MacroAssembler* masm, Register obj, Register tmp1, Register tmp2, Label& L_error);
 
 #ifdef COMPILER1
   void keepalive_barrier_c1_stub(LIR_Assembler* ce, ShenandoahKeepaliveBarrierStub* stub);

diff --git a/src/hotspot/cpu/arm/frame_arm.hpp b/src/hotspot/cpu/arm/frame_arm.hpp
@@ -122,6 +122,4 @@
   // helper to update a map with callee-saved FP
   static void update_map_with_saved_link(RegisterMap* map, intptr_t** link_addr);
 
-  static jint interpreter_frame_expression_stack_direction() { return -1; }
-
 #endif // CPU_ARM_FRAME_ARM_HPP
diff --git a/src/hotspot/cpu/ppc/frame_ppc.hpp b/src/hotspot/cpu/ppc/frame_ppc.hpp
@@ -407,8 +407,6 @@
     align_wiggle                           =  1
   };
 
-  static jint interpreter_frame_expression_stack_direction() { return -1; }
-
   // returns the sending frame, without applying any barriers
   inline frame sender_raw(RegisterMap* map) const;
 

diff --git a/src/hotspot/cpu/ppc/gc/shenandoah/shenandoahBarrierSetAssembler_ppc.cpp b/src/hotspot/cpu/ppc/gc/shenandoah/shenandoahBarrierSetAssembler_ppc.cpp
@@ -659,6 +659,26 @@ void ShenandoahBarrierSetAssembler::try_peek_weak_handle_in_nmethod(MacroAssembl
   __ block_comment("} try_peek_weak_handle_in_nmethod (shenandoahgc)");
 }
 
+void ShenandoahBarrierSetAssembler::check_oop(MacroAssembler *masm, Register obj, const char* msg) {
+  if (!VerifyOops) {
+    return;
+  }
+
+  __ mr(R0, obj);
+
+  // This routine is sometimes called before applying GC barriers.
+  // With +COH, verification can touch the klass that may end up loading forwarding pointer instead.
+  Label L_skip;
+  if (UseCompactObjectHeaders) {
+    __ lbz(R0, in_bytes(ShenandoahThreadLocalData::gc_state_offset()), R16_thread);
+    __ andi_(R0, R0, ShenandoahHeap::HAS_FORWARDED);
+    __ bne(CR0, L_skip);
+  }
+
+  __ verify_oop(R0, msg);
+  __ bind(L_skip);
+}
+
 void ShenandoahBarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators,
                                                                      Register addr, Register count, Register preserve) {
   assert(ShenandoahCardBarrier, "Should have been checked by caller");

diff --git a/src/hotspot/cpu/ppc/gc/shenandoah/shenandoahBarrierSetAssembler_ppc.hpp b/src/hotspot/cpu/ppc/gc/shenandoah/shenandoahBarrierSetAssembler_ppc.hpp
@@ -125,6 +125,8 @@ class ShenandoahBarrierSetAssembler: public BarrierSetAssembler {
   virtual void try_peek_weak_handle_in_nmethod(MacroAssembler* masm, Register weak_handle, Register obj,
                                                Register tmp, Label& slow_path);
 
+  virtual void check_oop(MacroAssembler *masm, Register obj, const char* msg);
+
 #ifdef COMPILER2
   // Entry points from Matcher
   void load_c2(const MachNode* node, MacroAssembler* masm, Register dst, Register addr, int disp, Register tmp1, Register tmp2, bool narrow, bool acquire);

diff --git a/src/hotspot/cpu/riscv/frame_riscv.hpp b/src/hotspot/cpu/riscv/frame_riscv.hpp
@@ -218,8 +218,6 @@
   // deoptimization support
   void interpreter_frame_set_last_sp(intptr_t* last_sp);
 
-  static jint interpreter_frame_expression_stack_direction() { return -1; }
-
   // returns the sending frame, without applying any barriers
   inline frame sender_raw(RegisterMap* map) const;
 

diff --git a/src/hotspot/cpu/riscv/gc/shenandoah/shenandoahBarrierSetAssembler_riscv.cpp b/src/hotspot/cpu/riscv/gc/shenandoah/shenandoahBarrierSetAssembler_riscv.cpp
@@ -433,6 +433,32 @@ void ShenandoahBarrierSetAssembler::try_peek_weak_handle_in_nmethod(MacroAssembl
   __ bind(done);
 }
 
+void ShenandoahBarrierSetAssembler::check_oop(MacroAssembler* masm, Register obj, Register tmp1, Register tmp2, Label& L_error) {
+  // Check if the oop is in the right area of memory
+  __ mv(tmp2, (intptr_t) Universe::verify_oop_mask());
+  __ andr(tmp1, obj, tmp2);
+  __ mv(tmp2, (intptr_t) Universe::verify_oop_bits());
+
+  // Compare tmp1 and tmp2.
+  __ bne(tmp1, tmp2, L_error);
+
+  // This routine is sometimes called before applying GC barriers.
+  // With +COH, loading the klass may end up loading forwarding pointer instead.
+  Label L_skip;
+  if (UseCompactObjectHeaders) {
+    Address gc_state(xthread, ShenandoahThreadLocalData::gc_state_offset());
+    __ lbu(tmp1, gc_state);
+    __ test_bit(tmp1, tmp1, ShenandoahHeap::HAS_FORWARDED_BITPOS);
+    __ bnez(tmp1, L_skip);
+  }
+
+  // Make sure klass is 'reasonable', which is not zero.
+  __ load_narrow_klass(tmp1, obj);
+  __ beqz(tmp1, L_error);
+
+  __ bind(L_skip);
+}
+
 void ShenandoahBarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators,
                                                                      Register start, Register count, Register tmp) {
   assert(ShenandoahCardBarrier, "Did you mean to enable ShenandoahCardBarrier?");

diff --git a/src/hotspot/cpu/riscv/gc/shenandoah/shenandoahBarrierSetAssembler_riscv.hpp b/src/hotspot/cpu/riscv/gc/shenandoah/shenandoahBarrierSetAssembler_riscv.hpp
@@ -79,6 +79,7 @@ class ShenandoahBarrierSetAssembler: public BarrierSetAssembler {
                                              Register obj, Register tmp, Label& slowpath);
   virtual void try_peek_weak_handle_in_nmethod(MacroAssembler* masm, Register weak_handle, Register obj,
                                                Register tmp, Label& slow_path);
+  virtual void check_oop(MacroAssembler* masm, Register obj, Register tmp1, Register tmp2, Label& L_error);
 
 #ifdef COMPILER1
   void keepalive_barrier_c1_stub(LIR_Assembler* ce, ShenandoahKeepaliveBarrierStub* stub);

diff --git a/src/hotspot/cpu/riscv/globals_riscv.hpp b/src/hotspot/cpu/riscv/globals_riscv.hpp
@@ -103,7 +103,7 @@ define_pd_global(intx, InlineSmallCode,          1000);
   product(bool, UseZbb, false, DIAGNOSTIC, "Use Zbb instructions")               \
   product(bool, UseZbkb, false, EXPERIMENTAL, "Use Zbkb instructions")           \
   product(bool, UseZbs, false, DIAGNOSTIC, "Use Zbs instructions")               \
-  product(bool, UseZfa, false, EXPERIMENTAL, "Use Zfa instructions")             \
+  product(bool, UseZfa, false, DIAGNOSTIC, "Use Zfa instructions")               \
   product(bool, UseZfh, false, DIAGNOSTIC, "Use Zfh instructions")               \
   product(bool, UseZfhmin, false, DIAGNOSTIC, "Use Zfhmin instructions")         \
   product(bool, UseZacas, false, EXPERIMENTAL, "Use Zacas instructions")         \

diff --git a/src/hotspot/cpu/s390/abstractInterpreter_s390.cpp b/src/hotspot/cpu/s390/abstractInterpreter_s390.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2016 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -197,8 +197,10 @@ void AbstractInterpreter::layout_activation(Method* method,
     assert(is_bottom_frame && (sender_sp == caller->unextended_sp()),
            "must initialize sender_sp of bottom skeleton frame when pushing it");
   } else {
-    assert(caller->is_entry_frame() || caller->is_upcall_stub_frame(), "is there a new frame type??");
-    sender_sp = caller->sp(); // Call_stub only uses it's fp.
+    // For entry, upcall_stub, and native frames, sender_sp is simply the caller's sp.
+    // These frames use the standard C ABI and don't require adjustment.
+    assert(caller->is_entry_frame() || caller->is_upcall_stub_frame() || caller->is_native_frame(), "is there a new frame type??");
+    sender_sp = caller->sp();
   }
 
   interpreter_frame->interpreter_frame_set_method(method);

diff --git a/src/hotspot/cpu/s390/assembler_s390.hpp b/src/hotspot/cpu/s390/assembler_s390.hpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2016, 2024 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -3279,6 +3279,9 @@ class Assembler : public AbstractAssembler {
   static bool is_z_nop(address x) {
     return is_z_nop(* (short *) x);
   }
+  static bool is_z_illtrap(address x) {
+    return *(uint8_t*)x == 0u;
+  }
   static bool is_z_br(long x) {
     return is_z_bcr(x) && ((x & 0x00f0) == 0x00f0);
   }

diff --git a/src/hotspot/cpu/s390/c1_LIRAssembler_s390.cpp b/src/hotspot/cpu/s390/c1_LIRAssembler_s390.cpp
@@ -524,6 +524,7 @@ void LIR_Assembler::call(LIR_OpJavaCall* op, relocInfo::relocType rtype) {
   __ z_nop();
   __ z_brasl(Z_R14, op->addr());
   add_call_info(code_offset(), op->info());
+  __ post_call_nop();
 }
 
 void LIR_Assembler::ic_call(LIR_OpJavaCall* op) {
@@ -539,7 +540,7 @@ void LIR_Assembler::ic_call(LIR_OpJavaCall* op) {
   // CALL to fixup routine. Fixup routine uses ScopeDesc info
   // to determine who we intended to call.
   __ relocate(virtual_call_Relocation::spec(virtual_call_oop_addr));
-  call(op, relocInfo::none);
+  call(op, relocInfo::none); // call will emit a post call nop, see above method.
 }
 
 void LIR_Assembler::move_regs(Register from_reg, Register to_reg) {
@@ -2792,6 +2793,7 @@ void LIR_Assembler::rt_call(LIR_Opr result, address dest,
   if (info != nullptr) {
     add_call_info_here(info);
   }
+  __ post_call_nop();
 }
 
 void LIR_Assembler::volatile_move_op(LIR_Opr src, LIR_Opr dest, BasicType type, CodeEmitInfo* info) {
-Original file line number
+Diff line change
@@ Expand Up / @@ -81,6 +81,7 @@ AC_DEFUN([FLAGS_SETUP_LDFLAGS_HELPER], @@
           fi
           if test "x$ENABLE_LINKTIME_GC" = xtrue; then
+            BASIC_LDFLAGS_JVM_ONLY="$BASIC_LDFLAGS_JVM_ONLY -Wl,--gc-sections -Wl,--undefined=_ZTV8Metadata"
             BASIC_LDFLAGS_JDK_ONLY="$BASIC_LDFLAGS_JDK_ONLY -Wl,--gc-sections"
           fi
         fi
@@ Expand Down @@