Revert "Initial implementation of on-stack replacement (OSR)."

runtime/vm/assembler_x64.cc

Index: runtime/vm/assembler_x64.cc
diff --git a/runtime/vm/assembler_x64.cc b/runtime/vm/assembler_x64.cc
index c1d90dbb034c781a6dc39e3329833a2d5f16e1c5..238574920f2dab52fc0116bf904812c7ebdd5dfc 100644
--- a/runtime/vm/assembler_x64.cc
+++ b/runtime/vm/assembler_x64.cc
@@ -9,7 +9,6 @@
 #include "vm/heap.h"
 #include "vm/memory_region.h"
 #include "vm/runtime_entry.h"
-#include "vm/stack_frame.h"
 #include "vm/stub_code.h"
 
 namespace dart {
@@ -2280,16 +2279,15 @@ void Assembler::CallRuntime(const RuntimeEntry& entry) {
 
 
 void Assembler::EnterDartFrame(intptr_t frame_size) {
+  const intptr_t offset = CodeSize();
   EnterFrame(0);
   Label dart_entry;
   call(&dart_entry);
   Bind(&dart_entry);
-  // The runtime system assumes that the code marker address is
-  // kEntryPointToPcMarkerOffset bytes from the entry.  If there is any code
-  // generated before entering the frame, the address needs to be adjusted.
-  const intptr_t offset = kEntryPointToPcMarkerOffset - CodeSize();
+  // Adjust saved PC for any intrinsic code that could have been generated
+  // before a frame is created.
   if (offset != 0) {
-    addq(Address(RSP, 0), Immediate(offset));
+    addq(Address(RSP, 0), Immediate(-offset));
   }
   if (frame_size != 0) {
     subq(RSP, Immediate(frame_size));
@@ -2297,29 +2295,6 @@ void Assembler::EnterDartFrame(intptr_t frame_size) {
 }
 
 
-// On entry to a function compiled for OSR, the caller's frame pointer, the
-// stack locals, and any copied parameters are already in place.  The frame
-// pointer is already set up.  The PC marker is not correct for the
-// optimized function and there may be extra space for spill slots to
-// allocate.
-void Assembler::EnterOsrFrame(intptr_t extra_size) {
-  Label dart_entry;
-  call(&dart_entry);
-  Bind(&dart_entry);
-  // The runtime system assumes that the code marker address is
-  // kEntryPointToPcMarkerOffset bytes from the entry.  Since there is no
-  // code to set up the frame pointer, the address needs to be adjusted.
-  const intptr_t offset = kEntryPointToPcMarkerOffset - CodeSize();
-  if (offset != 0) {
-    addq(Address(RSP, 0), Immediate(offset));
-  }
-  popq(Address(RBP, kPcMarkerSlotFromFp * kWordSize));
-  if (extra_size != 0) {
-    subq(RSP, Immediate(extra_size));
-  }
-}
-
-
 void Assembler::EnterStubFrame() {
   EnterFrame(0);
   pushq(Immediate(0));  // Push 0 in the saved PC area for stub frames.