Files
swift-mirror/include/swift/Basic/Timer.h
2017-09-26 17:22:58 -07:00

104 lines
3.3 KiB
C++

//===--- Timer.h - Shared timers for compilation phases ---------*- C++ -*-===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
#ifndef SWIFT_BASIC_TIMER_H
#define SWIFT_BASIC_TIMER_H
#include "swift/Basic/LLVM.h"
#include "llvm/ADT/Optional.h"
#include "llvm/Support/Timer.h"
namespace swift {
/// A convenience class for declaring a timer that's part of the Swift
/// compilation timers group.
class SharedTimer {
enum class State {
Initial,
Skipped,
Enabled
};
static State CompilationTimersEnabled;
Optional<llvm::NamedRegionTimer> Timer;
public:
explicit SharedTimer(StringRef name) {
if (CompilationTimersEnabled == State::Enabled)
Timer.emplace(name, name, "swift", "Swift compilation");
else
CompilationTimersEnabled = State::Skipped;
}
/// Must be called before any SharedTimers have been created.
static void enableCompilationTimers() {
assert(CompilationTimersEnabled != State::Skipped &&
"a timer has already been created");
CompilationTimersEnabled = State::Enabled;
}
};
/// A SharedTimer for recursive routines.
/// void example() {
/// RecursiveSharedTimer::Guard guard; // MUST BE AT TOP SCOPE of function to work right!
/// ASTContext &ctx = getASTContext();
/// if (ctx.Stats) {
/// guard = ctx.Stats->getFrontendRecursiveSharedTimers().NominalTypeDecl__lookupDirect.getGuard();
// }
/// ...
/// }
class RecursiveSharedTimer {
private:
int recursionCount = 0;
const StringRef name;
llvm::Optional<SharedTimer> timer;
void enterRecursiveFunction() {
assert(recursionCount >= 0 && "too many exits");
if (recursionCount++ == 0)
timer.emplace(name);
}
void exitRecursiveFunction() {
assert(recursionCount > 0 && "too many exits");
if (--recursionCount == 0)
timer.reset();
}
public:
RecursiveSharedTimer(StringRef name) : name(name) {}
struct Guard {
// FIXME OPTIONAL??
RecursiveSharedTimer *recursiveTimerOrNull;
// All this stuff is to do an RAII object that be moved.
Guard(RecursiveSharedTimer *rst) : recursiveTimerOrNull(rst) {
if (recursiveTimerOrNull) recursiveTimerOrNull->enterRecursiveFunction();
}
Guard() : recursiveTimerOrNull(nullptr) {}
Guard(Guard &&other) { recursiveTimerOrNull = other.recursiveTimerOrNull; other.recursiveTimerOrNull = nullptr; }
Guard& operator=(Guard&& other) {
recursiveTimerOrNull = other.recursiveTimerOrNull;
other.recursiveTimerOrNull = nullptr;
return *this;
}
~Guard() { if (recursiveTimerOrNull) recursiveTimerOrNull->exitRecursiveFunction(); }
Guard(const Guard&) = delete;
Guard& operator=(const Guard&) = delete;
};
Guard getGuard() { return Guard(this); }
};
} // end namespace swift
#endif // SWIFT_BASIC_TIMER_H