Add a Compiler option to profile the compilation time

Sources/CodeGen/LLVM/LLVMProgram.swift

@@ -13,18 +13,25 @@ public struct LLVMProgram {
   /// The LLVM modules in the program.
   public private(set) var llvmModules: [ModuleDecl.ID: SwiftyLLVM.Module] = [:]
 
+  let profiler: ProfilingMeasurements?
+
   /// Creates a transpiling `ir`, whose main module is `mainModule`, for `target`.
   ///
   /// - Parameters:
   ///   - target: The machine for which `ir` is transpiled. Defaults to the current host.
   public init(
     _ ir: IR.Program,
     mainModule: ModuleDecl.ID,
-    for target: SwiftyLLVM.TargetMachine? = nil
+    for target: SwiftyLLVM.TargetMachine? = nil,
+    profileWith profiler: ProfilingMeasurements?
   ) throws {
+    self.profiler = profiler
     self.target = try target ?? SwiftyLLVM.TargetMachine(for: .host())
     for m in ir.modules.keys {
       var context = CodeGenerationContext(forCompiling: m, of: ir)
+      let probe = profiler?.createAndStartProfilingProbe(MeasurementType.IRConversion)
+      defer { probe?.stop() }
+
       let transpilation = SwiftyLLVM.Module(transpiling: m, in: &context)
       do {
         try transpilation.verify()
@@ -38,6 +45,8 @@ public struct LLVMProgram {
 
   /// Applies the mandatory IR simplification passes on each module in `self`.
   public mutating func applyMandatoryPasses() {
+    let probe = profiler?.createAndStartProfilingProbe(MeasurementType.MandatoryPass)
+    defer { probe?.stop() }
     for k in llvmModules.keys {
       llvmModules[k]!.runDefaultModulePasses(optimization: .none, for: target)
     }
@@ -47,6 +56,8 @@ public struct LLVMProgram {
   ///
   /// Optimization applied are similar to clang's `-O3`.
   public mutating func optimize() {
+    let probe = profiler?.createAndStartProfilingProbe(MeasurementType.Optimizations)
+    defer { probe?.stop() }
     for k in llvmModules.keys {
       llvmModules[k]!.runDefaultModulePasses(optimization: .aggressive, for: target)
     }
@@ -63,6 +74,8 @@ public struct LLVMProgram {
     var result: [URL] = []
     for m in llvmModules.values {
       let f = directory.appendingPathComponent(m.name).appendingPathExtension("o")
+      let probe = profiler?.createAndStartProfilingProbe(MeasurementType.EmitPhase)
+      defer { probe?.stop() }
       try m.write(type, for: target, to: f.fileSystemPath)
       result.append(f)
     }

Sources/Driver/Driver.swift

@@ -95,6 +95,11 @@
     help: "Type-check the input file(s).")
   private var typeCheckOnly: Bool = false
 
+  @Flag(
+    name: [.customLong("profile-compiler")],
+    help: "Profile the compilation time")
+  private var profileCompiler: Bool = false
+
   @Option(
     name: [.customLong("trace-inference")],
     help: ArgumentHelp(
@@ -241,13 +246,18 @@
 
     let productName = makeProductName(inputs)
 
+    // Pool of measurements for time profiling
+    var profiler: ProfilingMeasurements? = profileCompiler ? ProfilingMeasurements() : nil
+    defer { profiler?.printProfilingReport() }
+
     // There's no need to load the standard library under `--emit raw-ast`.
     if outputType == .rawAST {
       var a = AST()
       _ = try a.loadModule(
         productName, parsing: sourceFiles(in: inputs),
         withBuiltinModuleAccess: importBuiltinModule,
-        reportingDiagnosticsTo: &log)
+        reportingDiagnosticsTo: &log,
+        profileWith: profiler)
       try write(a, to: astFile(productName))
       return
     }
@@ -266,7 +276,8 @@
         annotating: ScopedProgram(a), inParallel: experimentalParallelTypeChecking,
         reportingDiagnosticsTo: &log,
         tracingInferenceIf: shouldTraceInference,
-        loggingRequirementSystemIf: shouldLogRequirements)
+        loggingRequirementSystemIf: shouldLogRequirements,
+        profileWith: profiler)
     }
 
     let (program, sourceModule) = try dependencies.loadModule(
@@ -277,14 +288,14 @@
       try ast.loadModule(
         productName, parsing: sourceFiles(in: inputs), inNodeSpace: space,
         withBuiltinModuleAccess: importBuiltinModule,
-        reportingDiagnosticsTo: &log)
+        reportingDiagnosticsTo: &log,
+        profileWith: profiler)
     }
 
     if typeCheckOnly { return }
 
     // IR
-
-    var ir = try lower(program: program, reportingDiagnosticsTo: &log)
+    var ir = try lower(program: program, reportingDiagnosticsTo: &log, profileWith: profiler)
 
     if outputType == .ir || outputType == .rawIR {
       let m = ir.modules[sourceModule]!
@@ -295,7 +306,7 @@
     // LLVM
 
     logVerbose("begin depolymorphization pass.\n")
-    ir.depolymorphize()
+    ir.depolymorphize(profileWith: profiler)
 
     logVerbose("create LLVM target machine.\n")
     #if os(Windows)
@@ -305,7 +316,8 @@
     #endif
 
     logVerbose("create LLVM program.\n")
-    var llvmProgram = try LLVMProgram(ir, mainModule: sourceModule, for: target)
+    var llvmProgram = try LLVMProgram(
+      ir, mainModule: sourceModule, for: target, profileWith: profiler)
 
     logVerbose("LLVM mandatory passes.\n")
     llvmProgram.applyMandatoryPasses()
@@ -340,11 +352,14 @@
     let binaryPath = executableOutputPath(default: productName)
 
     #if os(macOS)
-      try makeMacOSExecutable(at: binaryPath, linking: objectFiles, diagnostics: &log)
+      try makeMacOSExecutable(
+        at: binaryPath, linking: objectFiles, diagnostics: &log, profileWith: profiler)
     #elseif os(Linux)
-      try makeLinuxExecutable(at: binaryPath, linking: objectFiles, diagnostics: &log)
+      try makeLinuxExecutable(
+        at: binaryPath, linking: objectFiles, diagnostics: &log, profileWith: profiler)
     #elseif os(Windows)
-      try makeWindowsExecutable(at: binaryPath, linking: objectFiles, diagnostics: &log)
+      try makeWindowsExecutable(
+        at: binaryPath, linking: objectFiles, diagnostics: &log, profileWith: profiler)
     #else
       _ = (objectFiles, binaryPath)
       UNIMPLEMENTED()
@@ -379,8 +394,11 @@
   ///
   /// Mandatory IR passes are applied unless `self.outputType` is `.rawIR`.
   private func lower(
-    program: TypedProgram, reportingDiagnosticsTo log: inout DiagnosticSet
+    program: TypedProgram, reportingDiagnosticsTo log: inout DiagnosticSet,
+    profileWith profiler: ProfilingMeasurements?
   ) throws -> IR.Program {
+    let probe = profiler?.createAndStartProfilingProbe(MeasurementType.IRLowering)
+    defer { probe?.stop() }
     var loweredModules: [ModuleDecl.ID: IR.Module] = [:]
     for d in program.ast.modules {
       loweredModules[d] = try lower(d, in: program, reportingDiagnosticsTo: &log)
@@ -410,9 +428,15 @@
   /// Combines the object files located at `objects` into an executable file at `binaryPath`,
   /// logging diagnostics to `log`.
   private func makeMacOSExecutable(
-    at binaryPath: String, linking objects: [URL], diagnostics: inout DiagnosticSet
+    at binaryPath: String, linking objects: [URL], diagnostics: inout DiagnosticSet,
+    profileWith profiler: ProfilingMeasurements?
   ) throws {
     let xcrun = try findExecutable(invokedAs: "xcrun").fileSystemPath
+
+    // linking profiling probe
+    let probe = profiler?.createAndStartProfilingProbe(MeasurementType.LinkPhase)
+    defer { probe?.stop() }
+
     let sdk =
       try runCommandLine(xcrun, ["--sdk", "macosx", "--show-sdk-path"], diagnostics: &diagnostics)
       ?? ""
@@ -434,7 +458,8 @@
   private func makeLinuxExecutable(
     at binaryPath: String,
     linking objects: [URL],
-    diagnostics: inout DiagnosticSet
+    diagnostics: inout DiagnosticSet,
+    profileWith profiler: ProfilingMeasurements?
   ) throws {
     var arguments = [
       "-o", binaryPath,
@@ -443,6 +468,10 @@
     arguments.append(contentsOf: objects.map(\.fileSystemPath))
     arguments.append(contentsOf: libraries.map({ "-l\($0)" }))
 
+    // linking profiling probe
+    let probe = profiler?.createAndStartProfilingProbe(MeasurementType.LinkPhase)
+    defer { probe?.stop() }
+
     // Note: We use "clang" rather than "ld" so that to deal with the entry point of the program.
     // See https://stackoverflow.com/questions/51677440
     try runCommandLine(
@@ -454,8 +483,13 @@
   private func makeWindowsExecutable(
     at binaryPath: String,
     linking objects: [URL],
-    diagnostics: inout DiagnosticSet
+    diagnostics: inout DiagnosticSet,
+    profileWith profiler: ProfilingMeasurements?
   ) throws {
+    // linking profiling probe
+    let probe = profiler?.createAndStartProfilingProbe(MeasurementType.LinkPhase)
+    defer { probe?.stop() }
+
     try runCommandLine(
       findExecutable(invokedAs: "lld-link").fileSystemPath,
       ["-defaultlib:HyloLibC", "-defaultlib:msvcrt", "-out:" + binaryPath]

Sources/FrontEnd/AST/AST.swift

@@ -107,12 +107,13 @@ public struct AST {
   public mutating func loadModule<S: Sequence>(
     _ name: String, parsing sourceCode: S, inNodeSpace space: Int? = nil,
     withBuiltinModuleAccess builtinModuleAccess: Bool = false,
-    reportingDiagnosticsTo log: inout DiagnosticSet
+    reportingDiagnosticsTo log: inout DiagnosticSet,
+    profileWith profiler: ProfilingMeasurements? = nil
   ) throws -> ModuleDecl.ID where S.Element == SourceFile {
     try loadModule(reportingDiagnosticsTo: &log) { (me, log, k) in
       // Suppress thrown diagnostics until all files are parsed.
       let translations = sourceCode.compactMap { (f) in
-        try? Parser.parse(f, inNodeSpace: k, in: &me, diagnostics: &log)
+        try? Parser.parse(f, inNodeSpace: k, in: &me, diagnostics: &log, profileWith: profiler)
       }
 
       let m = me.insert(
@@ -446,7 +447,7 @@ public struct AST {
 
       case TuplePattern.self:
         let x = TuplePattern.ID(pattern)!
-        for i in 0 ..< self[x].elements.count {
+        for i in 0..<self[x].elements.count {
           visit(pattern: self[x].elements[i].pattern, subfield: subfield + [i], result: &result)
         }
 

Sources/FrontEnd/AST/NodeIDs/DeclIDs.swift

@@ -35,7 +35,7 @@ public struct DeclIDs {
 
   /// The identifiers in `self` denoting type extending declarations.
   public var extensions: ArraySlice<AnyDeclID> {
-    all[0 ..< extensionEndIndex]
+    all[0..<extensionEndIndex]
   }
 
   /// The identifiers in `self` _not_ denoting type extending declarations.

Sources/FrontEnd/Parse/Lexer.swift

@@ -1,3 +1,5 @@
+import Utils
+
 /// A type that tokenize a source file.
 public struct Lexer: IteratorProtocol, Sequence {
 
@@ -7,10 +9,13 @@ public struct Lexer: IteratorProtocol, Sequence {
   /// The current position in the source file.
   private(set) var index: String.Index
 
+  private let profiler: ProfilingMeasurements?
+
   /// Creates a lexer generating tokens from the contents of `source`.
-  public init(tokenizing source: SourceFile) {
+  public init(tokenizing source: SourceFile, profileWith profiler: ProfilingMeasurements? = nil) {
     self.sourceCode = source
     self.index = source.text.startIndex
+    self.profiler = profiler
   }
 
   /// The current location of the lexer in `sourceCode`.
@@ -21,6 +26,10 @@ public struct Lexer: IteratorProtocol, Sequence {
 
   /// Advances to the next token and returns it, or returns `nil` if no next token exists.
   public mutating func next() -> Token? {
+    // Start measuring Lexer time
+    let probe = profiler?.createAndStartProfilingProbe(MeasurementType.Lexer)
+    defer { probe?.stop() }
+
     // Skip whitespaces and comments.
     while true {
       if index == sourceCode.text.endIndex { return nil }
@@ -54,7 +63,7 @@ public struct Lexer: IteratorProtocol, Sequence {
           } else {
             return Token(
               kind: .unterminatedBlockComment,
-              site: sourceCode.range(start ..< index))
+              site: sourceCode.range(start..<index))
           }
         }
 
@@ -68,12 +77,12 @@ public struct Lexer: IteratorProtocol, Sequence {
 
     // Scan a new token.
     let head = sourceCode.text[index]
-    var token = Token(kind: .invalid, site: location ..< location)
+    var token = Token(kind: .invalid, site: location..<location)
 
     // Try scan for exponent if previous token was .int
     if previousTokenWasInt, let next = peek(), next == "e" || next == "E" {
       discard()
-      if let _ = scanIntegralLiteral(allowingPlus: true) {
+      if scanIntegralLiteral(allowingPlus: true) != nil {
         token.kind = .exponent
       }
       token.site.extend(upTo: index)
@@ -160,7 +169,7 @@ public struct Lexer: IteratorProtocol, Sequence {
         if peek() == "`" {
           let start = sourceCode.position(sourceCode.text.index(after: token.site.startIndex))
           token.kind = .name
-          token.site = start ..< location
+          token.site = start..<location
           discard()
           return token
         } else {
@@ -242,7 +251,7 @@ public struct Lexer: IteratorProtocol, Sequence {
       case "<", ">":
         // Leading angle brackets are tokenized individually, to parse generic clauses.
         discard()
-        oper = sourceCode.text[token.site.startIndex ..< index]
+        oper = sourceCode.text[token.site.startIndex..<index]
 
       default:
         oper = take(while: { $0.isOperator })
@@ -348,7 +357,7 @@ public struct Lexer: IteratorProtocol, Sequence {
       index = sourceCode.text.index(after: index)
     }
 
-    return sourceCode.text[start ..< index]
+    return sourceCode.text[start..<index]
   }
 
   /// Consumes an integral literal and returns its kind, or returns `nil` if it fails to scan a valid integer.
@@ -405,23 +414,23 @@ extension Character {
   /// Indicates whether `self` character represents a decimal digit.
   fileprivate var isDecDigit: Bool {
     guard let ascii = asciiValue else { return false }
-    return (0x30 ... 0x39) ~= ascii  // 0 ... 9
+    return (0x30...0x39) ~= ascii  // 0 ... 9
       || 0x5f == ascii  // _
   }
 
   /// Indicates whether `self` represents an hexadecimal digit.
   fileprivate var isHexDigit: Bool {
     guard let ascii = asciiValue else { return false }
-    return (0x30 ... 0x39) ~= ascii  // 0 ... 9
-      || (0x41 ... 0x46) ~= ascii  // A ... F
-      || (0x61 ... 0x66) ~= ascii  // a ... f
+    return (0x30...0x39) ~= ascii  // 0 ... 9
+      || (0x41...0x46) ~= ascii  // A ... F
+      || (0x61...0x66) ~= ascii  // a ... f
       || 0x5f == ascii  // _
   }
 
   /// /// Indicates whether `self` represents an octal digit.
   fileprivate var isOctDigit: Bool {
     guard let ascii = asciiValue else { return false }
-    return (0x30 ... 0x37) ~= ascii  // 0 ... 7
+    return (0x30...0x37) ~= ascii  // 0 ... 7
       || 0x5f == ascii  // _
   }
 

Sources/FrontEnd/Parse/Parser+Diagnostics.swift

@@ -11,7 +11,7 @@ extension Diagnostic {
   static func error(expected subject: String, at location: SourcePosition, notes: [Diagnostic] = [])
     -> Diagnostic
   {
-    .error("expected \(subject)", at: location ..< location, notes: notes)
+    .error("expected \(subject)", at: location..<location, notes: notes)
   }
 
   static func error(
@@ -41,11 +41,11 @@ extension Diagnostic {
   }
 
   static func error(unterminatedCommentStartingAt p: SourcePosition) -> Diagnostic {
-    .error("unterminated comment", at: p ..< p)
+    .error("unterminated comment", at: p..<p)
   }
 
   static func error(unterminatedStringStartingAt p: SourcePosition) -> Diagnostic {
-    .error("unterminated string", at: p ..< p)
+    .error("unterminated string", at: p..<p)
   }
 
   static func error(duplicateAccessModifier m: SourceRepresentable<AccessModifier>) -> Diagnostic {