Implement tracking and optimizations of packed arrays

src/mips/code-stubs-mips.cc

Index: src/mips/code-stubs-mips.cc
diff --git a/src/mips/code-stubs-mips.cc b/src/mips/code-stubs-mips.cc
index f3dd95b851453cff69a738b4d7fc52cf0ff89461..54207acbe700fe35ee68266693de48ad60e03b80 100644
--- a/src/mips/code-stubs-mips.cc
+++ b/src/mips/code-stubs-mips.cc
@@ -7362,7 +7362,7 @@ static const AheadOfTimeWriteBarrierStubList kAheadOfTime[] = {
   // KeyedStoreStubCompiler::GenerateStoreFastElement.
   { REG(a3), REG(a2), REG(t0), EMIT_REMEMBERED_SET },
   { REG(a2), REG(a3), REG(t0), EMIT_REMEMBERED_SET },
-  // ElementsTransitionGenerator::GenerateSmiOnlyToObject
+  // ElementsTransitionGenerator::GenerateMapChangeElementTransition
   // and ElementsTransitionGenerator::GenerateSmiOnlyToDouble
   // and ElementsTransitionGenerator::GenerateDoubleToObject
   { REG(a2), REG(a3), REG(t5), EMIT_REMEMBERED_SET },
@@ -7629,7 +7629,7 @@ void StoreArrayLiteralElementStub::Generate(MacroAssembler* masm) {
   Label fast_elements;
 
   __ CheckFastElements(a2, t1, &double_elements);
-  // FAST_SMI_ONLY_ELEMENTS or FAST_ELEMENTS
+  // Check Smi or Object elements
   __ JumpIfSmi(a0, &smi_element);
   __ CheckFastSmiOnlyElements(a2, t1, &fast_elements);
 
@@ -7656,8 +7656,7 @@ void StoreArrayLiteralElementStub::Generate(MacroAssembler* masm) {
   __ Ret(USE_DELAY_SLOT);
   __ mov(v0, a0);
 
-  // Array literal has ElementsKind of FAST_SMI_ONLY_ELEMENTS or
-  // FAST_ELEMENTS, and value is Smi.
+  // Array literal has FAST_* elements and value is Smi.
   __ bind(&smi_element);
   __ lw(t1, FieldMemOperand(a1, JSObject::kElementsOffset));
   __ sll(t2, a3, kPointerSizeLog2 - kSmiTagSize);