MIPS: port Merge experimental/gc branch to the bleeding_edge.

src/mips/macro-assembler-mips.h

Index: src/mips/macro-assembler-mips.h
diff --git a/src/mips/macro-assembler-mips.h b/src/mips/macro-assembler-mips.h
index 5f60aa1e107aa1ea91f3efe67f7e421fb34a9282..7d2292ff3bb201a3910564fe3c8e4e2ac9b6600a 100644
--- a/src/mips/macro-assembler-mips.h
+++ b/src/mips/macro-assembler-mips.h
@@ -92,6 +92,13 @@ enum BranchDelaySlot {
 };
 
 
+enum RememberedSetAction { EMIT_REMEMBERED_SET, OMIT_REMEMBERED_SET };
+enum SmiCheck { INLINE_SMI_CHECK, OMIT_SMI_CHECK };
+enum RAStatus { kRAHasNotBeenSaved, kRAHasBeenSaved };
+
+bool AreAliased(Register r1, Register r2, Register r3, Register r4);
+
+
 // -----------------------------------------------------------------------------
 // Static helper functions.
 
@@ -240,6 +247,7 @@ class MacroAssembler: public Assembler {
     Branch(L);
   }
 
+
   // Load an object from the root table.
   void LoadRoot(Register destination,
                 Heap::RootListIndex index);
@@ -255,39 +263,126 @@ class MacroAssembler: public Assembler {
                  Condition cond, Register src1, const Operand& src2);
 
 
-  // Check if object is in new space.
-  // scratch can be object itself, but it will be clobbered.
-  void InNewSpace(Register object,
-                  Register scratch,
-                  Condition cc,  // eq for new space, ne otherwise.
-                  Label* branch);
+  // ---------------------------------------------------------------------------
+  // GC Support
+
+  void IncrementalMarkingRecordWriteHelper(Register object,
+                                           Register value,
+                                           Register address);
+
+  enum RememberedSetFinalAction {
+    kReturnAtEnd,
+    kFallThroughAtEnd
+  };
+
+
+  // Record in the remembered set the fact that we have a pointer to new space
+  // at the address pointed to by the addr register.  Only works if addr is not
+  // in new space.
+  void RememberedSetHelper(Register addr,
+                           Register scratch,
+                           SaveFPRegsMode save_fp,
+                           RememberedSetFinalAction and_then);
+
+  void CheckPageFlag(Register object,
+                     Register scratch,
+                     int mask,
+                     Condition cc,
+                     Label* condition_met);
+
+  // Check if object is in new space.  Jumps if the object is not in new space.
+  // The register scratch can be object itself, but it will be clobbered.
+  void JumpIfNotInNewSpace(Register object,
+                           Register scratch,
+                           Label* branch) {
+    InNewSpace(object, scratch, ne, branch);
+  }
+
+  // Check if object is in new space.  Jumps if the object is in new space.
+  // The register scratch can be object itself, but it will be clobbered.
+  void JumpIfInNewSpace(Register object,
+                        Register scratch,
+                        Label* branch) {
+    InNewSpace(object, scratch, eq, branch);
+  }
 
+  // Check if an object has a given incremental marking color.
+  void HasColor(Register object,
+                Register scratch0,
+                Register scratch1,
+                Label* has_color,
+                int first_bit,
+                int second_bit);
 
-  // For the page containing |object| mark the region covering [address]
-  // dirty. The object address must be in the first 8K of an allocated page.
-  void RecordWriteHelper(Register object,
-                         Register address,
-                         Register scratch);
-
-  // For the page containing |object| mark the region covering
-  // [object+offset] dirty. The object address must be in the first 8K
-  // of an allocated page.  The 'scratch' registers are used in the
-  // implementation and all 3 registers are clobbered by the
-  // operation, as well as the 'at' register. RecordWrite updates the
-  // write barrier even when storing smis.
-  void RecordWrite(Register object,
-                   Operand offset,
+  void JumpIfBlack(Register object,
                    Register scratch0,
-                   Register scratch1);
+                   Register scratch1,
+                   Label* on_black);
+
+  // Checks the color of an object.  If the object is already grey or black
+  // then we just fall through, since it is already live.  If it is white and
+  // we can determine that it doesn't need to be scanned, then we just mark it
+  // black and fall through.  For the rest we jump to the label so the
+  // incremental marker can fix its assumptions.
+  void EnsureNotWhite(Register object,
+                      Register scratch1,
+                      Register scratch2,
+                      Register scratch3,
+                      Label* object_is_white_and_not_data);
 
-  // For the page containing |object| mark the region covering
-  // [address] dirty. The object address must be in the first 8K of an
-  // allocated page.  All 3 registers are clobbered by the operation,
-  // as well as the ip register. RecordWrite updates the write barrier
-  // even when storing smis.
-  void RecordWrite(Register object,
-                   Register address,
-                   Register scratch);
+  // Detects conservatively whether an object is data-only, ie it does need to
+  // be scanned by the garbage collector.
+  void JumpIfDataObject(Register value,
+                        Register scratch,
+                        Label* not_data_object);
+
+  // Notify the garbage collector that we wrote a pointer into an object.
+  // |object| is the object being stored into, |value| is the object being
+  // stored.  value and scratch registers are clobbered by the operation.
+  // The offset is the offset from the start of the object, not the offset from
+  // the tagged HeapObject pointer.  For use with FieldOperand(reg, off).
+  void RecordWriteField(
+      Register object,
+      int offset,
+      Register value,
+      Register scratch,
+      RAStatus ra_status,
+      SaveFPRegsMode save_fp,
+      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
+      SmiCheck smi_check = INLINE_SMI_CHECK);
+
+  // As above, but the offset has the tag presubtracted.  For use with
+  // MemOperand(reg, off).
+  inline void RecordWriteContextSlot(
+      Register context,
+      int offset,
+      Register value,
+      Register scratch,
+      RAStatus ra_status,
+      SaveFPRegsMode save_fp,
+      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
+      SmiCheck smi_check = INLINE_SMI_CHECK) {
+    RecordWriteField(context,
+                     offset + kHeapObjectTag,
+                     value,
+                     scratch,
+                     ra_status,
+                     save_fp,
+                     remembered_set_action,
+                     smi_check);
+  }
+
+  // For a given |object| notify the garbage collector that the slot |address|
+  // has been written.  |value| is the object being stored. The value and
+  // address registers are clobbered by the operation.
+  void RecordWrite(
+      Register object,
+      Register address,
+      Register value,
+      RAStatus ra_status,
+      SaveFPRegsMode save_fp,
+      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
+      SmiCheck smi_check = INLINE_SMI_CHECK);
 
 
   // ---------------------------------------------------------------------------
@@ -1266,6 +1361,19 @@ class MacroAssembler: public Assembler {
                            Register scratch1,
                            Register scratch2);
 
+  // Helper for implementing JumpIfNotInNewSpace and JumpIfInNewSpace.
+  void InNewSpace(Register object,
+                  Register scratch,
+                  Condition cond,  // eq for new space, ne otherwise.
+                  Label* branch);
+
+  // Helper for finding the mark bits for an address.  Afterwards, the
+  // bitmap register points at the word with the mark bits and the mask
+  // the position of the first bit.  Leaves addr_reg unchanged.
+  inline void GetMarkBits(Register addr_reg,
+                          Register bitmap_reg,
+                          Register mask_reg);
+
   // Compute memory operands for safepoint stack slots.
   static int SafepointRegisterStackIndex(int reg_code);
   MemOperand SafepointRegisterSlot(Register reg);