Track prologue offset of Code and use for more precise return addresses

runtime/vm/assembler_x64.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // NOLINT
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/assembler.h"
 #include "vm/cpu.h"
 #include "vm/heap.h"
@@ skipping 3206 matching lines @@
     ASSERT(Utils::IsInt(8, offset));
     buffer_.Store<int8_t>(position, offset);
   }
   label->BindTo(bound);
 }
 
 
 void Assembler::EnterFrame(intptr_t frame_size) {
   if (prologue_offset_ == -1) {
     prologue_offset_ = CodeSize();
+    Comment("PrologueOffset = %" Pd "", CodeSize());
   }
+#ifdef DEBUG
+  intptr_t check_offset = CodeSize();
+#endif
   pushq(RBP);
   movq(RBP, RSP);
+#ifdef DEBUG
+  ProloguePattern pp(CodeAddress(check_offset));
+  ASSERT(pp.IsValid());
+#endif
   if (frame_size != 0) {
     Immediate frame_space(frame_size);
     subq(RSP, frame_space);
   }
 }
 
 
 void Assembler::LeaveFrame() {
   movq(RSP, RBP);
   popq(RBP);
@@ skipping 159 matching lines @@
 
 
 // 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,
                               Register new_pp,
                               Register pc_marker_override) {
+  if (prologue_offset_ == -1) {
+    Comment("PrologueOffset = %" Pd "", CodeSize());
+    prologue_offset_ = CodeSize();
+  }
   movq(Address(RBP, kPcMarkerSlotFromFp * kWordSize), pc_marker_override);
   movq(PP, new_pp);
   if (extra_size != 0) {
     subq(RSP, Immediate(extra_size));
   }
 }
 
 
 void Assembler::EnterStubFrame(bool load_pp) {
   EnterFrame(0);
@@ skipping 477 matching lines @@
 
 
 const char* Assembler::FpuRegisterName(FpuRegister reg) {
   ASSERT((0 <= reg) && (reg < kNumberOfXmmRegisters));
   return xmm_reg_names[reg];
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64