Refactor operations to be on String (swiftlang#664)

Finish refactoring logic onto String

Author: milseman

Sources/RegexBenchmark/Utils/Stats.swift

@@ -3,8 +3,8 @@ import Foundation
 enum Stats {}
 
 extension Stats {
-  // Maximum allowed standard deviation is 5% of the median runtime
-  static let maxAllowedStdev = 0.05
+  // Maximum allowed standard deviation is 7.5% of the median runtime
+  static let maxAllowedStdev = 0.075
 
   static func tTest(_ a: Measurement, _ b: Measurement) -> Bool {
     // Student's t-test

Sources/_StringProcessing/Engine/MEBuiltins.swift

@@ -15,7 +15,7 @@ extension Processor {
     isStrictASCII: Bool,
     isScalarSemantics: Bool
   ) -> Bool {
-    guard let next = input._matchBuiltinCC(
+    guard let next = input.matchBuiltinCC(
       cc,
       at: currentPosition,
       isInverted: isInverted,
@@ -123,7 +123,7 @@ extension Processor {
 extension String {
   // TODO: Should the below have a `limitedBy` parameter?
 
-  func _matchAnyNonNewline(
+  func matchAnyNonNewline(
     at currentPosition: String.Index,
     isScalarSemantics: Bool
   ) -> String.Index? {
@@ -145,7 +145,7 @@ extension String {
   }
 
   @inline(__always)
-  func _quickMatchAnyNonNewline(
+  private func _quickMatchAnyNonNewline(
     at currentPosition: String.Index,
     isScalarSemantics: Bool
   ) -> QuickResult<String.Index?> {
@@ -165,7 +165,7 @@ extension String {
   }
 
   @inline(never)
-  func _thoroughMatchAnyNonNewline(
+  private func _thoroughMatchAnyNonNewline(
     at currentPosition: String.Index,
     isScalarSemantics: Bool
   ) -> String.Index? {
@@ -187,7 +187,7 @@ extension String {
   // TODO: Should the below have a `limitedBy` parameter?
 
   // Mentioned in ProgrammersManual.md, update docs if redesigned
-  func _matchBuiltinCC(
+  func matchBuiltinCC(
     _ cc: _CharacterClassModel.Representation,
     at currentPosition: String.Index,
     isInverted: Bool,
@@ -222,7 +222,7 @@ extension String {
 
   // Mentioned in ProgrammersManual.md, update docs if redesigned
   @inline(__always)
-  func _quickMatchBuiltinCC(
+  private func _quickMatchBuiltinCC(
     _ cc: _CharacterClassModel.Representation,
     at currentPosition: String.Index,
     isInverted: Bool,
@@ -240,7 +240,7 @@ extension String {
 
   // Mentioned in ProgrammersManual.md, update docs if redesigned
   @inline(never)
-  func _thoroughMatchBuiltinCC(
+  private func _thoroughMatchBuiltinCC(
     _ cc: _CharacterClassModel.Representation,
     at currentPosition: String.Index,
     isInverted: Bool,

Sources/_StringProcessing/Engine/MEQuantify.swift

@@ -1,21 +1,27 @@
 extension Processor {
   func _doQuantifyMatch(_ payload: QuantifyPayload) -> Input.Index? {
-    // FIXME: is the below updated for scalar semantics?
+    // TODO: This optimization is only enabled for grapheme cluster semantics,
+    //       we want these for scalar semantics as well.
+
     switch payload.type {
     case .bitset:
       return input.matchBitset(
-        registers[payload.bitset], at: currentPosition, limitedBy: end)
+        registers[payload.bitset],
+        at: currentPosition,
+        limitedBy: end,
+        isScalarSemantics: false)
     case .asciiChar:
       return input.matchScalar(
         UnicodeScalar.init(_value: UInt32(payload.asciiChar)),
         at: currentPosition,
         limitedBy: end,
-        boundaryCheck: true)
+        boundaryCheck: true,
+        isCaseInsensitive: false)
     case .builtin:
       // FIXME: bounds check? endIndex or end?
 
       // We only emit .quantify if it consumes a single character
-      return input._matchBuiltinCC(
+      return input.matchBuiltinCC(
         payload.builtin,
         at: currentPosition,
         isInverted: payload.builtinIsInverted,
@@ -29,7 +35,7 @@ extension Processor {
         return input.index(after: currentPosition)
       }
 
-      return input._matchAnyNonNewline(
+      return input.matchAnyNonNewline(
         at: currentPosition, isScalarSemantics: false)
     }
   }
@@ -41,7 +47,7 @@ extension Processor {
     var trips = 0
     var extraTrips = payload.extraTrips
     var savePoint = startQuantifierSavePoint()
-    
+
     while true {
       if trips >= payload.minTrips {
         if extraTrips == 0 { break }