Add Smi::Zero and replace all Smi::FromInt(0) calls

src/code-stub-assembler.cc

Index: src/code-stub-assembler.cc
diff --git a/src/code-stub-assembler.cc b/src/code-stub-assembler.cc
index 2d8e55ca29a75ece438945adf38799dc1633f0f5..d3b4d99352cd8df190e906b3c9b23f9ba7916109 100644
--- a/src/code-stub-assembler.cc
+++ b/src/code-stub-assembler.cc
@@ -38,9 +38,7 @@ void CodeStubAssembler::Assert(Node* condition) {
 #endif
 }
 
-Node* CodeStubAssembler::NoContextConstant() {
-  return SmiConstant(Smi::FromInt(0));
-}
+Node* CodeStubAssembler::NoContextConstant() { return SmiConstant(Smi::kZero); }
 
 #define HEAP_CONSTANT_ACCESSOR(rootName, name)     \
   Node* CodeStubAssembler::name##Constant() {      \
@@ -614,7 +612,7 @@ Node* CodeStubAssembler::AllocateRawUnaligned(Node* size_in_bytes,
 
   Bind(&runtime_call);
   // AllocateInTargetSpace does not use the context.
-  Node* context = SmiConstant(Smi::FromInt(0));
+  Node* context = SmiConstant(Smi::kZero);
 
   Node* runtime_result;
   if (flags & kPretenured) {
@@ -1677,8 +1675,7 @@ void CodeStubAssembler::CopyStringCharacters(compiler::Node* from_string,
 
   // Nothing to do for zero characters.
 
-  GotoIf(SmiLessThanOrEqual(character_count, SmiConstant(Smi::FromInt(0))),
-         &out);
+  GotoIf(SmiLessThanOrEqual(character_count, SmiConstant(Smi::kZero)), &out);
 
   // Calculate offsets into the strings.
 
@@ -2734,7 +2731,7 @@ Node* CodeStubAssembler::SubString(Node* context, Node* string, Node* from,
     GotoIf(SmiAbove(substr_length, string_length), &runtime);
 
     // Equal length - check if {from, to} == {0, str.length}.
-    GotoIf(SmiAbove(from, SmiConstant(Smi::FromInt(0))), &runtime);
+    GotoIf(SmiAbove(from, SmiConstant(Smi::kZero)), &runtime);
 
     // Return the original string (substr_length == string_length).
 
@@ -3055,7 +3052,7 @@ Node* CodeStubAssembler::ToInteger(Node* context, Node* input,
     }
 
     Bind(&return_zero);
-    var_arg.Bind(SmiConstant(Smi::FromInt(0)));
+    var_arg.Bind(SmiConstant(Smi::kZero));
     Goto(&out);
   }
 
@@ -5647,7 +5644,7 @@ void CodeStubAssembler::CheckEnumCache(Node* receiver, Label* use_cache,
     // For all objects but the receiver, check that the cache is empty.
     current_map.Bind(LoadMap(current_js_object.value()));
     Node* enum_length = EnumLength(current_map.value());
-    Node* zero_constant = SmiConstant(Smi::FromInt(0));
+    Node* zero_constant = SmiConstant(Smi::kZero);
     BranchIf(WordEqual(enum_length, zero_constant), &loop, use_runtime);
   }
 }