[turbofan] Frame elision for code stubs

src/compiler/pipeline.cc

Index: src/compiler/pipeline.cc
diff --git a/src/compiler/pipeline.cc b/src/compiler/pipeline.cc
index 1de88d7e1753a805685a90181b88d280359a52bf..729d4189af96844018d62f822b567b45c27dcd32 100644
--- a/src/compiler/pipeline.cc
+++ b/src/compiler/pipeline.cc
@@ -1368,6 +1368,7 @@ Handle<Code> Pipeline::ScheduleAndGenerateCode(
   AllocateRegisters(
       RegisterConfiguration::ArchDefault(RegisterConfiguration::TURBOFAN),
       call_descriptor, run_verifier);
+  Run<FrameElisionPhase>();
   if (data->compilation_failed()) {
     info()->AbortOptimization(kNotEnoughVirtualRegistersRegalloc);
     return Handle<Code>();
@@ -1376,11 +1377,7 @@ Handle<Code> Pipeline::ScheduleAndGenerateCode(
   BeginPhaseKind("code generation");
   // TODO(mtrofin): move this off to the register allocator.
   bool generate_frame_at_start =
-      !FLAG_turbo_frame_elision || !data_->info()->IsStub() ||
-      !data_->frame()->needs_frame() ||
-      data_->sequence()->instruction_blocks().front()->needs_frame() ||
-      linkage.GetIncomingDescriptor()->CalleeSavedFPRegisters() != 0 ||
-      linkage.GetIncomingDescriptor()->CalleeSavedRegisters() != 0;
+      data_->sequence()->instruction_blocks().front()->must_construct_frame();
   // Optimimize jumps.
   if (FLAG_turbo_jt) {
     Run<JumpThreadingPhase>(generate_frame_at_start);
@@ -1499,8 +1496,11 @@ void Pipeline::AllocateRegisters(const RegisterConfiguration* config,
     Run<OptimizeMovesPhase>();
   }
 
+  if (descriptor != nullptr && descriptor->RequiresFrameAsIncoming()) {
+    data_->sequence()->instruction_blocks()[0]->mark_needs_frame();
+  }
+
   Run<LocateSpillSlotsPhase>();
-  Run<FrameElisionPhase>();
 
   if (FLAG_trace_turbo_graph) {
     OFStream os(stdout);