diff a/src/hotspot/cpu/aarch64/c1_MacroAssembler_aarch64.cpp b/src/hotspot/cpu/aarch64/c1_MacroAssembler_aarch64.cpp
--- a/src/hotspot/cpu/aarch64/c1_MacroAssembler_aarch64.cpp
+++ b/src/hotspot/cpu/aarch64/c1_MacroAssembler_aarch64.cpp
@@ -26,10 +26,12 @@
 #include "precompiled.hpp"
 #include "c1/c1_MacroAssembler.hpp"
 #include "c1/c1_Runtime1.hpp"
 #include "gc/shared/barrierSetAssembler.hpp"
 #include "gc/shared/collectedHeap.hpp"
+#include "gc/shared/barrierSet.hpp"
+#include "gc/shared/barrierSetAssembler.hpp"
 #include "gc/shared/tlab_globals.hpp"
 #include "interpreter/interpreter.hpp"
 #include "oops/arrayOop.hpp"
 #include "oops/markWord.hpp"
 #include "runtime/basicLock.hpp"
@@ -86,10 +88,16 @@
     Label done;
     // Load object header
     ldr(hdr, Address(obj, hdr_offset));
     // and mark it as unlocked
     orr(hdr, hdr, markWord::unlocked_value);
+
+    if (EnableValhalla) {
+      // Mask always_locked bit such that we go to the slow path if object is an inline type
+      andr(hdr, hdr, ~markWord::inline_type_bit_in_place);
+    }
+
     // save unlocked object header into the displaced header location on the stack
     str(hdr, Address(disp_hdr, 0));
     // test if object header is still the same (i.e. unlocked), and if so, store the
     // displaced header address in the object header - if it is not the same, get the
     // object header instead
@@ -173,12 +181,18 @@
   }
 }
 
 void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) {
   assert_different_registers(obj, klass, len);
-  // This assumes that all prototype bits fit in an int32_t
-  mov(t1, (int32_t)(intptr_t)markWord::prototype().value());
+  if (EnableValhalla) {
+    // Need to copy markWord::prototype header for klass
+    assert_different_registers(obj, klass, len, t1, t2);
+    ldr(t1, Address(klass, Klass::prototype_header_offset()));
+  } else {
+    // This assumes that all prototype bits fit in an int32_t
+    mov(t1, (int32_t)(intptr_t)markWord::prototype().value());
+  }
   str(t1, Address(obj, oopDesc::mark_offset_in_bytes()));
 
   if (UseCompressedClassPointers) { // Take care not to kill klass
     encode_klass_not_null(t1, klass);
     strw(t1, Address(obj, oopDesc::klass_offset_in_bytes()));
@@ -312,35 +326,111 @@
   }
 
   verify_oop(obj);
 }
 
-void C1_MacroAssembler::build_frame(int framesize, int bang_size_in_bytes) {
-  assert(bang_size_in_bytes >= framesize, "stack bang size incorrect");
+void C1_MacroAssembler::build_frame_helper(int frame_size_in_bytes, int sp_offset_for_orig_pc, int sp_inc, bool reset_orig_pc, bool needs_stack_repair) {
+  MacroAssembler::build_frame(frame_size_in_bytes);
+
+  if (needs_stack_repair) {
+    save_stack_increment(sp_inc, frame_size_in_bytes);
+  }
+  if (reset_orig_pc) {
+    // Zero orig_pc to detect deoptimization during buffering in the entry points
+    str(zr, Address(sp, sp_offset_for_orig_pc));
+  }
+}
+
+void C1_MacroAssembler::build_frame(int frame_size_in_bytes, int bang_size_in_bytes, int sp_offset_for_orig_pc, bool needs_stack_repair, bool has_scalarized_args, Label* verified_inline_entry_label) {
   // Make sure there is enough stack space for this method's activation.
   // Note that we do this before creating a frame.
+  assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
   generate_stack_overflow_check(bang_size_in_bytes);
-  MacroAssembler::build_frame(framesize);
+
+  build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, 0, has_scalarized_args, needs_stack_repair);
 
   // Insert nmethod entry barrier into frame.
   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
   bs->nmethod_entry_barrier(this, nullptr /* slow_path */, nullptr /* continuation */, nullptr /* guard */);
-}
 
-void C1_MacroAssembler::remove_frame(int framesize) {
-  MacroAssembler::remove_frame(framesize);
+  if (verified_inline_entry_label != nullptr) {
+    // Jump here from the scalarized entry points that already created the frame.
+    bind(*verified_inline_entry_label);
+  }
 }
 
-
 void C1_MacroAssembler::verified_entry(bool breakAtEntry) {
   // If we have to make this method not-entrant we'll overwrite its
   // first instruction with a jump.  For this action to be legal we
   // must ensure that this first instruction is a B, BL, NOP, BKPT,
   // SVC, HVC, or SMC.  Make it a NOP.
   nop();
+  if (C1Breakpoint) brk(1);
+}
+
+int C1_MacroAssembler::scalarized_entry(const CompiledEntrySignature* ces, int frame_size_in_bytes, int bang_size_in_bytes, int sp_offset_for_orig_pc, Label& verified_inline_entry_label, bool is_inline_ro_entry) {
+  assert(InlineTypePassFieldsAsArgs, "sanity");
+  // Make sure there is enough stack space for this method's activation.
+  assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
+  generate_stack_overflow_check(bang_size_in_bytes);
+
+  GrowableArray<SigEntry>* sig    = ces->sig();
+  GrowableArray<SigEntry>* sig_cc = is_inline_ro_entry ? ces->sig_cc_ro() : ces->sig_cc();
+  VMRegPair* regs      = ces->regs();
+  VMRegPair* regs_cc   = is_inline_ro_entry ? ces->regs_cc_ro() : ces->regs_cc();
+  int args_on_stack    = ces->args_on_stack();
+  int args_on_stack_cc = is_inline_ro_entry ? ces->args_on_stack_cc_ro() : ces->args_on_stack_cc();
+
+  assert(sig->length() <= sig_cc->length(), "Zero-sized inline class not allowed!");
+  BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sig_cc->length());
+  int args_passed = sig->length();
+  int args_passed_cc = SigEntry::fill_sig_bt(sig_cc, sig_bt);
+
+  // Create a temp frame so we can call into the runtime. It must be properly set up to accommodate GC.
+  build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, 0, true, ces->c1_needs_stack_repair());
+
+  // The runtime call might safepoint, make sure nmethod entry barrier is executed
+  BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
+  // C1 code is not hot enough to micro optimize the nmethod entry barrier with an out-of-line stub
+  bs->nmethod_entry_barrier(this, nullptr /* slow_path */, nullptr /* continuation */, nullptr /* guard */);
+
+  // FIXME -- call runtime only if we cannot in-line allocate all the incoming inline type args.
+  mov(r19, (intptr_t) ces->method());
+  if (is_inline_ro_entry) {
+    far_call(RuntimeAddress(Runtime1::entry_for(C1StubId::buffer_inline_args_no_receiver_id)));
+  } else {
+    far_call(RuntimeAddress(Runtime1::entry_for(C1StubId::buffer_inline_args_id)));
+  }
+  int rt_call_offset = offset();
+
+  // The runtime call returns the new array in r20 instead of the usual r0
+  // because r0 is also j_rarg7 which may be holding a live argument here.
+  Register val_array = r20;
+
+  // Remove the temp frame
+  MacroAssembler::remove_frame(frame_size_in_bytes);
+
+  // Check if we need to extend the stack for packing
+  int sp_inc = 0;
+  if (args_on_stack > args_on_stack_cc) {
+    sp_inc = extend_stack_for_inline_args(args_on_stack);
+  }
+
+  shuffle_inline_args(true, is_inline_ro_entry, sig_cc,
+                      args_passed_cc, args_on_stack_cc, regs_cc, // from
+                      args_passed, args_on_stack, regs,          // to
+                      sp_inc, val_array);
+
+  // Create the real frame. Below jump will then skip over the stack banging and frame
+  // setup code in the verified_inline_entry (which has a different real_frame_size).
+  build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, sp_inc, false, ces->c1_needs_stack_repair());
+
+  b(verified_inline_entry_label);
+  return rt_call_offset;
 }
 
+
 void C1_MacroAssembler::load_parameter(int offset_in_words, Register reg) {
   // rfp, + 0: link
   //     + 1: return address
   //     + 2: argument with offset 0
   //     + 3: argument with offset 1
