[turbofan] Reland "Add new JSFrameSpecialization reducer." and "Perform OSR deconstruction early an…

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index fa0726c4ac3e6a296ca6b7affbaf94d634b1b8cb..3f4bd27ec6a3ce875d40ee962924a02fe0fc512b 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -582,16 +582,6 @@ Bounds Typer::Visitor::TypeParameter(Node* node) {
 
 
 Bounds Typer::Visitor::TypeOsrValue(Node* node) {
-  if (node->InputAt(0)->opcode() == IrOpcode::kOsrLoopEntry) {
-    // Before deconstruction, OSR values have type {None} to avoid polluting
-    // the types of phis and other nodes in the graph.
-    return Bounds(Type::None(), Type::None());
-  }
-  if (NodeProperties::IsTyped(node)) {
-    // After deconstruction, OSR values may have had a type explicitly set.
-    return NodeProperties::GetBounds(node);
-  }
-  // Otherwise, be conservative.
   return Bounds::Unbounded(zone());
 }