[cleanup] Only accept TNodes in CSA StringToNumber.

Change-Id: Idf3a38c0750071263c6450a17d311cbab632523c
Reviewed-on: https://chromium-review.googlesource.com/924141Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51327}

src/builtins/builtins-conversion-gen.cc

@@ -99,7 +99,7 @@ TF_BUILTIN(NonPrimitiveToPrimitive_String, ConversionBuiltinsAssembler) {
 }
 
 TF_BUILTIN(StringToNumber, CodeStubAssembler) {
-  Node* input = Parameter(Descriptor::kArgument);
+  TNode<String> input = CAST(Parameter(Descriptor::kArgument));
 
   Return(StringToNumber(input));
 }

src/code-stub-assembler.cc

@@ -5328,8 +5328,7 @@ TNode<String> CodeStubAssembler::StringFromCodePoint(TNode<Int32T> codepoint,
   return CAST(var_result.value());
 }
 
-TNode<Number> CodeStubAssembler::StringToNumber(SloppyTNode<String> input) {
-  CSA_SLOW_ASSERT(this, IsString(input));
+TNode<Number> CodeStubAssembler::StringToNumber(TNode<String> input) {
   Label runtime(this, Label::kDeferred);
   Label end(this);
 
@@ -5510,7 +5509,8 @@ Node* CodeStubAssembler::NonNumberToNumberOrNumeric(
     BIND(&if_inputisstring);
     {
       // The {input} is a String, use the fast stub to convert it to a Number.
-      var_result.Bind(StringToNumber(input));
+      TNode<String> string_input = CAST(input);
+      var_result.Bind(StringToNumber(string_input));
       Goto(&end);
     }
 

src/code-stub-assembler.h

@@ -1227,7 +1227,7 @@ class V8_EXPORT_PRIVATE CodeStubAssembler : public compiler::CodeAssembler {
   // Type conversion helpers.
   enum class BigIntHandling { kConvertToNumber, kThrow };
   // Convert a String to a Number.
-  TNode<Number> StringToNumber(SloppyTNode<String> input);
+  TNode<Number> StringToNumber(TNode<String> input);
   // Convert a Number to a String.
   Node* NumberToString(Node* input);
   // Convert an object to a name.