diff --git a/src/mips/macro-assembler-mips.cc b/src/mips/macro-assembler-mips.cc
index 604293b..90c3499 100644
--- a/src/mips/macro-assembler-mips.cc
+++ b/src/mips/macro-assembler-mips.cc
@@ -15,7 +15,7 @@
 #include "src/cpu-profiler.h"
 #include "src/debug.h"
 #include "src/isolate-inl.h"
-#include "src/runtime.h"
+#include "src/runtime/runtime.h"
 
 namespace v8 {
 namespace internal {
@@ -23,7 +23,8 @@
 MacroAssembler::MacroAssembler(Isolate* arg_isolate, void* buffer, int size)
     : Assembler(arg_isolate, buffer, size),
       generating_stub_(false),
-      has_frame_(false) {
+      has_frame_(false),
+      has_double_zero_reg_set_(false) {
   if (isolate() != NULL) {
     code_object_ = Handle<Object>(isolate()->heap()->undefined_value(),
                                   isolate());
@@ -590,11 +591,12 @@
   }
 
   bind(&done);
-  // Check that the value is a normal property.
+  // Check that the value is a field property.
   // reg2: elements + (index * kPointerSize).
   const int kDetailsOffset =
       SeededNumberDictionary::kElementsStartOffset + 2 * kPointerSize;
   lw(reg1, FieldMemOperand(reg2, kDetailsOffset));
+  DCHECK_EQ(FIELD, 0);
   And(at, reg1, Operand(Smi::FromInt(PropertyDetails::TypeField::kMask)));
   Branch(miss, ne, at, Operand(zero_reg));
 
@@ -739,6 +741,28 @@
 }
 
 
+void MacroAssembler::Mulhu(Register rd, Register rs, const Operand& rt) {
+  if (rt.is_reg()) {
+    if (!IsMipsArchVariant(kMips32r6)) {
+      multu(rs, rt.rm());
+      mfhi(rd);
+    } else {
+      muhu(rd, rs, rt.rm());
+    }
+  } else {
+    // li handles the relocation.
+    DCHECK(!rs.is(at));
+    li(at, rt);
+    if (!IsMipsArchVariant(kMips32r6)) {
+      multu(rs, at);
+      mfhi(rd);
+    } else {
+      muhu(rd, rs, at);
+    }
+  }
+}
+
+
 void MacroAssembler::Multu(Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     multu(rs, rt.rm());
@@ -790,6 +814,28 @@
 }
 
 
+void MacroAssembler::Div(Register res, Register rs, const Operand& rt) {
+  if (rt.is_reg()) {
+    if (!IsMipsArchVariant(kMips32r6)) {
+      div(rs, rt.rm());
+      mflo(res);
+    } else {
+      div(res, rs, rt.rm());
+    }
+  } else {
+    // li handles the relocation.
+    DCHECK(!rs.is(at));
+    li(at, rt);
+    if (!IsMipsArchVariant(kMips32r6)) {
+      div(rs, at);
+      mflo(res);
+    } else {
+      div(res, rs, at);
+    }
+  }
+}
+
+
 void MacroAssembler::Mod(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     if (!IsMipsArchVariant(kMips32r6)) {
@@ -812,6 +858,28 @@
 }
 
 
+void MacroAssembler::Modu(Register rd, Register rs, const Operand& rt) {
+  if (rt.is_reg()) {
+    if (!IsMipsArchVariant(kMips32r6)) {
+      divu(rs, rt.rm());
+      mfhi(rd);
+    } else {
+      modu(rd, rs, rt.rm());
+    }
+  } else {
+    // li handles the relocation.
+    DCHECK(!rs.is(at));
+    li(at, rt);
+    if (!IsMipsArchVariant(kMips32r6)) {
+      divu(rs, at);
+      mfhi(rd);
+    } else {
+      modu(rd, rs, at);
+    }
+  }
+}
+
+
 void MacroAssembler::Divu(Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     divu(rs, rt.rm());
@@ -824,6 +892,28 @@
 }
 
 
+void MacroAssembler::Divu(Register res, Register rs, const Operand& rt) {
+  if (rt.is_reg()) {
+    if (!IsMipsArchVariant(kMips32r6)) {
+      divu(rs, rt.rm());
+      mflo(res);
+    } else {
+      divu(res, rs, rt.rm());
+    }
+  } else {
+    // li handles the relocation.
+    DCHECK(!rs.is(at));
+    li(at, rt);
+    if (!IsMipsArchVariant(kMips32r6)) {
+      divu(rs, at);
+      mflo(res);
+    } else {
+      divu(res, rs, at);
+    }
+  }
+}
+
+
 void MacroAssembler::And(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     and_(rd, rs, rt.rm());
@@ -1459,15 +1549,20 @@
 }
 
 
+void MacroAssembler::Move(FPURegister dst, float imm) {
+  li(at, Operand(bit_cast<int32_t>(imm)));
+  mtc1(at, dst);
+}
+
+
 void MacroAssembler::Move(FPURegister dst, double imm) {
   static const DoubleRepresentation minus_zero(-0.0);
   static const DoubleRepresentation zero(0.0);
   DoubleRepresentation value_rep(imm);
   // Handle special values first.
-  bool force_load = dst.is(kDoubleRegZero);
-  if (value_rep == zero && !force_load) {
+  if (value_rep == zero && has_double_zero_reg_set_) {
     mov_d(dst, kDoubleRegZero);
-  } else if (value_rep == minus_zero && !force_load) {
+  } else if (value_rep == minus_zero && has_double_zero_reg_set_) {
     neg_d(dst, kDoubleRegZero);
   } else {
     uint32_t lo, hi;
@@ -1488,6 +1583,7 @@
     } else {
       Mthc1(zero_reg, dst);
     }
+    if (dst.is(kDoubleRegZero)) has_double_zero_reg_set_ = true;
   }
 }
 
@@ -1904,7 +2000,7 @@
       // Unsigned comparison.
       case Ugreater:
         if (r2.is(zero_reg)) {
-          bgtz(rs, offset);
+          bne(rs, zero_reg, offset);
         } else {
           sltu(scratch, r2, rs);
           bne(scratch, zero_reg, offset);
@@ -1912,7 +2008,7 @@
         break;
       case Ugreater_equal:
         if (r2.is(zero_reg)) {
-          bgez(rs, offset);
+          b(offset);
         } else {
           sltu(scratch, rs, r2);
           beq(scratch, zero_reg, offset);
@@ -1929,7 +2025,7 @@
         break;
       case Uless_equal:
         if (r2.is(zero_reg)) {
-          b(offset);
+          beq(rs, zero_reg, offset);
         } else {
           sltu(scratch, r2, rs);
           beq(scratch, zero_reg, offset);
@@ -1948,18 +2044,26 @@
         b(offset);
         break;
       case eq:
-        // We don't want any other register but scratch clobbered.
-        DCHECK(!scratch.is(rs));
-        r2 = scratch;
-        li(r2, rt);
-        beq(rs, r2, offset);
+        if (rt.imm32_ == 0) {
+          beq(rs, zero_reg, offset);
+        } else {
+          // We don't want any other register but scratch clobbered.
+          DCHECK(!scratch.is(rs));
+          r2 = scratch;
+          li(r2, rt);
+          beq(rs, r2, offset);
+        }
         break;
       case ne:
-        // We don't want any other register but scratch clobbered.
-        DCHECK(!scratch.is(rs));
-        r2 = scratch;
-        li(r2, rt);
-        bne(rs, r2, offset);
+        if (rt.imm32_ == 0) {
+          bne(rs, zero_reg, offset);
+        } else {
+          // We don't want any other register but scratch clobbered.
+          DCHECK(!scratch.is(rs));
+          r2 = scratch;
+          li(r2, rt);
+          bne(rs, r2, offset);
+        }
         break;
       // Signed comparison.
       case greater:
@@ -2011,7 +2115,7 @@
       // Unsigned comparison.
       case Ugreater:
         if (rt.imm32_ == 0) {
-          bgtz(rs, offset);
+          bne(rs, zero_reg, offset);
         } else {
           r2 = scratch;
           li(r2, rt);
@@ -2021,7 +2125,7 @@
         break;
       case Ugreater_equal:
         if (rt.imm32_ == 0) {
-          bgez(rs, offset);
+          b(offset);
         } else if (is_int16(rt.imm32_)) {
           sltiu(scratch, rs, rt.imm32_);
           beq(scratch, zero_reg, offset);
@@ -2048,7 +2152,7 @@
         break;
       case Uless_equal:
         if (rt.imm32_ == 0) {
-          b(offset);
+          beq(rs, zero_reg, offset);
         } else {
           r2 = scratch;
           li(r2, rt);
@@ -2150,7 +2254,7 @@
       case Ugreater:
         if (r2.is(zero_reg)) {
           offset = shifted_branch_offset(L, false);
-           bgtz(rs, offset);
+          bne(rs, zero_reg, offset);
         } else {
           sltu(scratch, r2, rs);
           offset = shifted_branch_offset(L, false);
@@ -2160,7 +2264,7 @@
       case Ugreater_equal:
         if (r2.is(zero_reg)) {
           offset = shifted_branch_offset(L, false);
-          bgez(rs, offset);
+          b(offset);
         } else {
           sltu(scratch, rs, r2);
           offset = shifted_branch_offset(L, false);
@@ -2180,7 +2284,7 @@
       case Uless_equal:
         if (r2.is(zero_reg)) {
           offset = shifted_branch_offset(L, false);
-          b(offset);
+          beq(rs, zero_reg, offset);
         } else {
           sltu(scratch, r2, rs);
           offset = shifted_branch_offset(L, false);
@@ -2201,18 +2305,28 @@
         b(offset);
         break;
       case eq:
-        DCHECK(!scratch.is(rs));
-        r2 = scratch;
-        li(r2, rt);
-        offset = shifted_branch_offset(L, false);
-        beq(rs, r2, offset);
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          beq(rs, zero_reg, offset);
+        } else {
+          DCHECK(!scratch.is(rs));
+          r2 = scratch;
+          li(r2, rt);
+          offset = shifted_branch_offset(L, false);
+          beq(rs, r2, offset);
+        }
         break;
       case ne:
-        DCHECK(!scratch.is(rs));
-        r2 = scratch;
-        li(r2, rt);
-        offset = shifted_branch_offset(L, false);
-        bne(rs, r2, offset);
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          bne(rs, zero_reg, offset);
+        } else {
+          DCHECK(!scratch.is(rs));
+          r2 = scratch;
+          li(r2, rt);
+          offset = shifted_branch_offset(L, false);
+          bne(rs, r2, offset);
+        }
         break;
       // Signed comparison.
       case greater:
@@ -2292,7 +2406,7 @@
       case Ugreater_equal:
         if (rt.imm32_ == 0) {
           offset = shifted_branch_offset(L, false);
-          bgez(rs, offset);
+          b(offset);
         } else if (is_int16(rt.imm32_)) {
           sltiu(scratch, rs, rt.imm32_);
           offset = shifted_branch_offset(L, false);
@@ -3884,17 +3998,17 @@
 }
 
 
-void MacroAssembler::DispatchMap(Register obj,
-                                 Register scratch,
-                                 Handle<Map> map,
-                                 Handle<Code> success,
-                                 SmiCheckType smi_check_type) {
+void MacroAssembler::DispatchWeakMap(Register obj, Register scratch1,
+                                     Register scratch2, Handle<WeakCell> cell,
+                                     Handle<Code> success,
+                                     SmiCheckType smi_check_type) {
   Label fail;
   if (smi_check_type == DO_SMI_CHECK) {
     JumpIfSmi(obj, &fail);
   }
-  lw(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
-  Jump(success, RelocInfo::CODE_TARGET, eq, scratch, Operand(map));
+  lw(scratch1, FieldMemOperand(obj, HeapObject::kMapOffset));
+  GetWeakValue(scratch2, cell);
+  Jump(success, RelocInfo::CODE_TARGET, eq, scratch1, Operand(scratch2));
   bind(&fail);
 }
 
@@ -3913,6 +4027,19 @@
 }
 
 
+void MacroAssembler::GetWeakValue(Register value, Handle<WeakCell> cell) {
+  li(value, Operand(cell));
+  lw(value, FieldMemOperand(value, WeakCell::kValueOffset));
+}
+
+
+void MacroAssembler::LoadWeakValue(Register value, Handle<WeakCell> cell,
+                                   Label* miss) {
+  GetWeakValue(value, cell);
+  JumpIfSmi(value, miss);
+}
+
+
 void MacroAssembler::MovFromFloatResult(DoubleRegister dst) {
   if (IsMipsSoftFloatABI) {
     if (kArchEndian == kLittle) {
@@ -4477,8 +4604,34 @@
 }
 
 
-void MacroAssembler::AdduAndCheckForOverflow(Register dst,
-                                             Register left,
+void MacroAssembler::AdduAndCheckForOverflow(Register dst, Register left,
+                                             const Operand& right,
+                                             Register overflow_dst,
+                                             Register scratch) {
+  if (right.is_reg()) {
+    AdduAndCheckForOverflow(dst, left, right.rm(), overflow_dst, scratch);
+  } else {
+    if (dst.is(left)) {
+      mov(scratch, left);                   // Preserve left.
+      addiu(dst, left, right.immediate());  // Left is overwritten.
+      xor_(scratch, dst, scratch);          // Original left.
+      // Load right since xori takes uint16 as immediate.
+      addiu(t9, zero_reg, right.immediate());
+      xor_(overflow_dst, dst, t9);
+      and_(overflow_dst, overflow_dst, scratch);
+    } else {
+      addiu(dst, left, right.immediate());
+      xor_(overflow_dst, dst, left);
+      // Load right since xori takes uint16 as immediate.
+      addiu(t9, zero_reg, right.immediate());
+      xor_(scratch, dst, t9);
+      and_(overflow_dst, scratch, overflow_dst);
+    }
+  }
+}
+
+
+void MacroAssembler::AdduAndCheckForOverflow(Register dst, Register left,
                                              Register right,
                                              Register overflow_dst,
                                              Register scratch) {
@@ -4519,8 +4672,34 @@
 }
 
 
-void MacroAssembler::SubuAndCheckForOverflow(Register dst,
-                                             Register left,
+void MacroAssembler::SubuAndCheckForOverflow(Register dst, Register left,
+                                             const Operand& right,
+                                             Register overflow_dst,
+                                             Register scratch) {
+  if (right.is_reg()) {
+    SubuAndCheckForOverflow(dst, left, right.rm(), overflow_dst, scratch);
+  } else {
+    if (dst.is(left)) {
+      mov(scratch, left);                      // Preserve left.
+      addiu(dst, left, -(right.immediate()));  // Left is overwritten.
+      xor_(overflow_dst, dst, scratch);        // scratch is original left.
+      // Load right since xori takes uint16 as immediate.
+      addiu(t9, zero_reg, right.immediate());
+      xor_(scratch, scratch, t9);  // scratch is original left.
+      and_(overflow_dst, scratch, overflow_dst);
+    } else {
+      addiu(dst, left, -(right.immediate()));
+      xor_(overflow_dst, dst, left);
+      // Load right since xori takes uint16 as immediate.
+      addiu(t9, zero_reg, right.immediate());
+      xor_(scratch, left, t9);
+      and_(overflow_dst, scratch, overflow_dst);
+    }
+  }
+}
+
+
+void MacroAssembler::SubuAndCheckForOverflow(Register dst, Register left,
                                              Register right,
                                              Register overflow_dst,
                                              Register scratch) {
@@ -4887,6 +5066,13 @@
 }
 
 
+void MacroAssembler::EnterFrame(StackFrame::Type type,
+                                bool load_constant_pool_pointer_reg) {
+  // Out-of-line constant pool not implemented on mips.
+  UNREACHABLE();
+}
+
+
 void MacroAssembler::EnterFrame(StackFrame::Type type) {
   addiu(sp, sp, -5 * kPointerSize);
   li(t8, Operand(Smi::FromInt(type)));
@@ -5619,18 +5805,6 @@
 }
 
 
-void MacroAssembler::CheckMapDeprecated(Handle<Map> map,
-                                        Register scratch,
-                                        Label* if_deprecated) {
-  if (map->CanBeDeprecated()) {
-    li(scratch, Operand(map));
-    lw(scratch, FieldMemOperand(scratch, Map::kBitField3Offset));
-    And(scratch, scratch, Operand(Map::Deprecated::kMask));
-    Branch(if_deprecated, ne, scratch, Operand(zero_reg));
-  }
-}
-
-
 void MacroAssembler::JumpIfBlack(Register object,
                                  Register scratch0,
                                  Register scratch1,