[turbofan]: Implement tail calls with more callee than caller parameters

src/compiler/x64/code-generator-x64.cc

Index: src/compiler/x64/code-generator-x64.cc
diff --git a/src/compiler/x64/code-generator-x64.cc b/src/compiler/x64/code-generator-x64.cc
index 1c80ad85baa8fd6eb5eec196ea8e00fa17f47782..cbb8b6b628a1564c01bdbda169250cdb59918c27 100644
--- a/src/compiler/x64/code-generator-x64.cc
+++ b/src/compiler/x64/code-generator-x64.cc
@@ -575,16 +575,37 @@ class OutOfLineRecordWrite final : public OutOfLineCode {
 
 void CodeGenerator::AssembleDeconstructActivationRecord(int stack_param_delta) {
   CallDescriptor* descriptor = linkage()->GetIncomingDescriptor();
-  int stack_slots = frame()->GetSpillSlotCount();
-  if (descriptor->IsJSFunctionCall() || stack_slots > 0) {
-    __ movq(rsp, rbp);
+  int spill_slots = frame()->GetSpillSlotCount();
+  bool has_frame = descriptor->IsJSFunctionCall() || spill_slots > 0;
+  if (has_frame) {
+    if (stack_param_delta != 0) {
+      int total_discarded_slots = frame()->GetTotalFrameSlotCount();
+      // Leave the PC and saved frame pointer on the stack.
+      total_discarded_slots -=
+          StandardFrameConstants::kFixedFrameSizeFromFp / kPointerSize;
+      // Discard only slots that won't be used by new parameters.
+      total_discarded_slots -= stack_param_delta;
+      if (total_discarded_slots > 0) {
+        __ addq(rsp, Immediate(total_discarded_slots * kPointerSize));
+      }
+    } else {
+      __ movq(rsp, rbp);
+    }
     __ popq(rbp);
   }
-  if (stack_param_delta < 0) {
-    int offset = -(stack_param_delta + 1) * kPointerSize;
-    __ popq(Operand(rsp, offset));
-    if (offset != 0) {
-      __ addq(rsp, Immediate(offset));
+}
+
+
+void CodeGenerator::AssemblePrepareTailCall(int stack_param_delta) {
+  if (stack_param_delta > 0) {
+    int total_discarded_slots = frame()->GetTotalFrameSlotCount();
+    // Leave the PC and saved frame pointer on the stack.
+    total_discarded_slots -=
+        StandardFrameConstants::kFixedFrameSizeFromFp / kPointerSize;
+    // Discard only slots that won't be used by new parameters.
+    total_discarded_slots -= stack_param_delta;
+    if (total_discarded_slots < 0) {
+      __ subq(rsp, Immediate(-total_discarded_slots * kPointerSize));
     }
   }
 }
@@ -655,6 +676,9 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       __ PrepareCallCFunction(num_parameters);
       break;
     }
+    case kArchPrepareTailCall:
+      AssemblePrepareTailCall(i.InputInt32(instr->InputCount() - 1));
+      break;
     case kArchCallCFunction: {
       int const num_parameters = MiscField::decode(instr->opcode());
       if (HasImmediateInput(instr, 0)) {