diff a/src/hotspot/cpu/x86/c1_MacroAssembler_x86.cpp b/src/hotspot/cpu/x86/c1_MacroAssembler_x86.cpp
--- a/src/hotspot/cpu/x86/c1_MacroAssembler_x86.cpp
+++ b/src/hotspot/cpu/x86/c1_MacroAssembler_x86.cpp
@@ -33,10 +33,11 @@
 #include "gc/shared/tlab_globals.hpp"
 #include "interpreter/interpreter.hpp"
 #include "oops/arrayOop.hpp"
 #include "oops/markWord.hpp"
 #include "runtime/basicLock.hpp"
+#include "runtime/frame.inline.hpp"
 #include "runtime/globals.hpp"
 #include "runtime/os.hpp"
 #include "runtime/sharedRuntime.hpp"
 #include "runtime/stubRoutines.hpp"
 #include "utilities/checkedCast.hpp"
@@ -76,10 +77,14 @@
     Label done;
     // Load object header
     movptr(hdr, Address(obj, hdr_offset));
     // and mark it as unlocked
     orptr(hdr, markWord::unlocked_value);
+    if (EnableValhalla) {
+      // Mask inline_type bit such that we go to the slow path if object is an inline type
+      andptr(hdr, ~((int) markWord::inline_type_bit_in_place));
+    }
     // save unlocked object header into the displaced header location on the stack
     movptr(Address(disp_hdr, 0), hdr);
     // 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
@@ -169,11 +174,19 @@
 }
 
 
 void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) {
   assert_different_registers(obj, klass, len);
-  movptr(Address(obj, oopDesc::mark_offset_in_bytes()), checked_cast<int32_t>(markWord::prototype().value()));
+  if (EnableValhalla) {
+    // Need to copy markWord::prototype header for klass
+    assert_different_registers(obj, klass, len, t1, t2);
+    movptr(t1, Address(klass, Klass::prototype_header_offset()));
+    movptr(Address(obj, oopDesc::mark_offset_in_bytes()), t1);
+  } else {
+    // This assumes that all prototype bits fit in an int32_t
+    movptr(Address(obj, oopDesc::mark_offset_in_bytes()), checked_cast<int32_t>(markWord::prototype().value()));
+  }
 #ifdef _LP64
   if (UseCompressedClassPointers) { // Take care not to kill klass
     movptr(t1, klass);
     encode_klass_not_null(t1, rscratch1);
     movl(Address(obj, oopDesc::klass_offset_in_bytes()), t1);
@@ -313,43 +326,56 @@
   }
 
   verify_oop(obj);
 }
 
-void C1_MacroAssembler::build_frame(int frame_size_in_bytes, int bang_size_in_bytes) {
-  assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
-  // Make sure there is enough stack space for this method's activation.
-  // Note that we do this before doing an enter(). This matches the
-  // ordering of C2's stack overflow check / rsp decrement and allows
-  // the SharedRuntime stack overflow handling to be consistent
-  // between the two compilers.
-  generate_stack_overflow_check(bang_size_in_bytes);
-
+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) {
   push(rbp);
   if (PreserveFramePointer) {
     mov(rbp, rsp);
   }
 #if !defined(_LP64) && defined(COMPILER2)
   if (UseSSE < 2 && !CompilerConfig::is_c1_only_no_jvmci()) {
-    // c2 leaves fpu stack dirty. Clean it on entry
-    empty_FPU_stack();
-  }
+      // c2 leaves fpu stack dirty. Clean it on entry
+      empty_FPU_stack();
+    }
 #endif // !_LP64 && COMPILER2
-  decrement(rsp, frame_size_in_bytes); // does not emit code for frame_size == 0
+  decrement(rsp, frame_size_in_bytes);
+
+  if (needs_stack_repair) {
+    // Save stack increment (also account for fixed framesize and rbp)
+    assert((sp_inc & (StackAlignmentInBytes-1)) == 0, "stack increment not aligned");
+    int real_frame_size = sp_inc + frame_size_in_bytes + wordSize;
+    movptr(Address(rsp, frame_size_in_bytes - wordSize), real_frame_size);
+  }
+  if (reset_orig_pc) {
+    // Zero orig_pc to detect deoptimization during buffering in the entry points
+    movptr(Address(rsp, sp_offset_for_orig_pc), 0);
+  }
+}
+
+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 doing an enter(). This matches the
+  // ordering of C2's stack overflow check / rsp decrement and allows
+  // the SharedRuntime stack overflow handling to be consistent
+  // between the two compilers.
+  assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
+  generate_stack_overflow_check(bang_size_in_bytes);
+
+  build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, 0, has_scalarized_args, needs_stack_repair);
 
   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 */);
-}
 
-
-void C1_MacroAssembler::remove_frame(int frame_size_in_bytes) {
-  increment(rsp, frame_size_in_bytes);  // Does not emit code for frame_size == 0
-  pop(rbp);
+  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 (breakAtEntry || VerifyFPU) {
     // Verified Entry first instruction should be 5 bytes long for correct
     // patching by patch_verified_entry().
     //
@@ -362,10 +388,68 @@
   if (breakAtEntry) int3();
   // build frame
   IA32_ONLY( verify_FPU(0, "method_entry"); )
 }
 
+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 */);
+
+  // FIXME -- call runtime only if we cannot in-line allocate all the incoming inline type args.
+  movptr(rbx, (intptr_t)(ces->method()));
+  if (is_inline_ro_entry) {
+    call(RuntimeAddress(Runtime1::entry_for(C1StubId::buffer_inline_args_no_receiver_id)));
+  } else {
+    call(RuntimeAddress(Runtime1::entry_for(C1StubId::buffer_inline_args_id)));
+  }
+  int rt_call_offset = offset();
+
+  // Remove the temp frame
+  addptr(rsp, frame_size_in_bytes);
+  pop(rbp);
+
+  // 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, rax);
+
+  // 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());
+
+  jmp(verified_inline_entry_label);
+  return rt_call_offset;
+}
+
 void C1_MacroAssembler::load_parameter(int offset_in_words, Register reg) {
   // rbp, + 0: link
   //     + 1: return address
   //     + 2: argument with offset 0
   //     + 3: argument with offset 1
