VM: New calling convention for generated code.

runtime/vm/assembler_arm.h

Index: runtime/vm/assembler_arm.h
diff --git a/runtime/vm/assembler_arm.h b/runtime/vm/assembler_arm.h
index 5fdaeac6d581b16664a4c51284c6859ef37c99ab..4714cec2c33330f6eda1f1a0ec3784d5973cfcdf 100644
--- a/runtime/vm/assembler_arm.h
+++ b/runtime/vm/assembler_arm.h
@@ -606,19 +606,18 @@ class Assembler : public ValueObject {
   void bx(Register rm, Condition cond = AL);
   void blx(Register rm, Condition cond = AL);
 
-  // Macros.
-  // Branch to an entry address. Call sequence is never patched.
-  void Branch(const StubEntry& stub_entry, Condition cond = AL);
-
-  // Branch to an entry address. Call sequence can be patched or even replaced.
-  void BranchPatchable(const StubEntry& stub_entry);
+  void Branch(const StubEntry& stub_entry,
+              Patchability patchable = kNotPatchable,
+              Register pp = PP,
+              Condition cond = AL);
 
   void BranchLink(const StubEntry& stub_entry,
                   Patchability patchable = kNotPatchable);
-  void BranchLink(const ExternalLabel* label, Patchability patchable);
+  void BranchLink(const Code& code, Patchability patchable);
 
   // Branch and link to an entry address. Call sequence can be patched.
   void BranchLinkPatchable(const StubEntry& stub_entry);
+  void BranchLinkPatchable(const Code& code);
 
   // Branch and link to [base + offset]. Call sequence is never patched.
   void BranchLinkOffset(Register base, int32_t offset);
@@ -661,7 +660,8 @@ class Assembler : public ValueObject {
 
   void Drop(intptr_t stack_elements);
 
-  void LoadPoolPointer();
+  void RestoreCodePointer();
+  void LoadPoolPointer(Register reg = PP);
 
   void LoadIsolate(Register rd);
 
@@ -671,6 +671,9 @@ class Assembler : public ValueObject {
                          const ExternalLabel* label,
                          Patchability patchable,
                          Condition cond = AL);
+  void LoadFunctionFromCalleePool(Register dst,
+                                  const Function& function,
+                                  Register new_pp);
   void LoadNativeEntry(Register dst,
                        const ExternalLabel* label,
                        Patchability patchable,
@@ -872,6 +875,8 @@ class Assembler : public ValueObject {
     b(is_smi, CC);
   }
 
+  void CheckCodePointer();
+
   // Function frame setup and tear down.
   void EnterFrame(RegList regs, intptr_t frame_space);
   void LeaveFrame(RegList regs);
@@ -890,7 +895,7 @@ class Assembler : public ValueObject {
   // enable easy access to the RawInstruction object of code corresponding
   // to this frame.
   void EnterDartFrame(intptr_t frame_size);
-  void LeaveDartFrame();
+  void LeaveDartFrame(RestorePP restore_pp = kRestoreCallerPP);
 
   // Set up a Dart frame for a function compiled for on-stack replacement.
   // The frame layout is a normal Dart frame, but the frame is partially set
@@ -902,13 +907,6 @@ class Assembler : public ValueObject {
   void EnterStubFrame();
   void LeaveStubFrame();
 
-  // Instruction pattern from entrypoint is used in Dart frame prologs
-  // to set up the frame and save a PC which can be used to figure out the
-  // RawInstruction object corresponding to the code running in the frame.
-  static intptr_t EntryPointToPcMarkerOffset() {
-    return TargetCPUFeatures::store_pc_read_offset();
-  }
-
   // The register into which the allocation stats table is loaded with
   // LoadAllocationStatsAddress should be passed to
   // IncrementAllocationStats(WithSize) as stats_addr_reg to update the
@@ -994,9 +992,12 @@ class Assembler : public ValueObject {
   void BindARMv6(Label* label);
   void BindARMv7(Label* label);
 
-  void BranchLink(const ExternalLabel* label);
+  void LoadWordFromPoolOffset(Register rd,
+                              int32_t offset,
+                              Register pp,
+                              Condition cond);
 
-  void LoadWordFromPoolOffset(Register rd, int32_t offset, Condition cond);
+  void BranchLink(const ExternalLabel* label);
 
   class CodeComment : public ZoneAllocated {
    public:
@@ -1020,7 +1021,8 @@ class Assembler : public ValueObject {
   void LoadObjectHelper(Register rd,
                         const Object& object,
                         Condition cond,
-                        bool is_unique);
+                        bool is_unique,
+                        Register pp);
 
   void EmitType01(Condition cond,
                   int type,