centralized performance resources

perf-cpp/scripts/.clang-format

@@ -0,0 +1,9 @@
+BasedOnStyle: Google
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortCompoundRequirementOnASingleLine: false
+AllowShortEnumsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: false
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLambdasOnASingleLine: false
+AllowShortLoopsOnASingleLine: false

perf-cpp/scripts/.clangd

@@ -0,0 +1,35 @@
+CompileFlags:
+	Add:
+		-O2
+		-Wall
+		-Wextra
+		-Wpedantic
+		-Wshadow
+		-Wformat=2
+		-Wfloat-equal
+		-Wlogical-op
+		-Wshift-overflow=2
+		-Wnon-virtual-dtor
+		-Wold-style-cast
+		-Wcast-qual
+		-Wuseless-cast
+		-Wno-sign-promotion
+		-Wcast-align
+		-Wunused
+		-Woverloaded-virtual
+		-Wconversion
+		-Wsign-conversion
+		-Wmisleading-indentation
+		-Wduplicated-cond
+		-Wduplicated-branches
+		-Wlogical-op
+		-Wnull-dereference
+		-Wformat=2
+		-Wformat-overflow
+		-Wformat-truncation
+		-Wdouble-promotion
+		-Wundef
+		-DLOCAL
+		-Wno-unknown-pragmas
+-e 		-std=c++23
+-e 		-std=c++23

perf-cpp/scripts/a.cc

@@ -0,0 +1,9 @@
+#include <iostream>
+
+#include "a.hh"
+
+int main() {
+  std::cout << add();
+
+  return 0;
+}

perf-cpp/scripts/a.hh

@@ -0,0 +1,3 @@
+#pragma once
+
+int add() {return 1;}

perf-cpp/scripts/bitset.cc

@@ -0,0 +1,29 @@
+#include <iostream>
+#include <bitset>
+
+using namespace std;
+
+#include <bitset>
+#include <iostream>
+
+std::bitset<4> rotl(std::bitset<4> bits) {
+  return (bits << 1) | (bits >> 3);
+}
+
+void william() {
+  int will;
+
+  if (69)
+    int will;
+}
+
+int main()
+{
+	std::bitset<4> bits1{ 0b0001 };
+	std::cout << rotl(bits1) << '\n';
+
+	std::bitset<4> bits2{ 0b1001 };
+	std::cout << rotl(bits2) << '\n';
+
+	return 0;
+}

perf-cpp/scripts/ch11.cc

@@ -0,0 +1,48 @@
+/*
+   Write a constexpr function template with a non-type template parameter that
+   returns the factorial of the template argument. The following program should
+   fail to compile when it reaches factorial<-3>().
+
+   */
+
+template <int N>
+constexpr long long fibonacci() {
+  static_assert(N >= 0);
+  if constexpr (N <= 1) {
+    return N;
+  } else {
+    return fibonacci<N - 1>() + fibonacci<N - 2>();
+  }
+}
+
+// int main() {
+//   static_assert(fibonacci<1LL>() == 1);
+//   // static_assert(factorial<3>() == 6);
+//   // static_assert(factorial<5>() == 120);
+//
+//   // fibonacci<-3>();
+//
+//   return 0;
+// }
+
+#include <iostream>
+
+template <typename T>
+T add(T x, T y) {
+  return x + y;
+}
+
+template <typename T>
+T mult(T t, int N) {
+  return t * N;
+}
+
+int main() {
+  std::cout << add(2, 3) << '\n';
+  std::cout << add(1.2, 3.4) << '\n';
+
+  std::cout << mult(2, 3) << '\n';
+  std::cout << mult(1.2, 3) << '\n';
+
+  return 0;
+}

perf-cpp/scripts/ch15.cc

@@ -0,0 +1,50 @@
+/*
+Question #1
+
+Write a class template named Triad that has 3 private data members with
+independent type template parameters. The class should have a constructor,
+access functions, and a print() member function that is defined outside the
+class.
+
+The following program should compile and run:
+*/
+
+#include <iostream>
+#include <string>
+
+template <typename T1, typename T2, typename T3>
+class Triad {
+ private:
+  T1 t1;
+  T2 t2;
+  T3 t3;
+
+ public:
+  explicit Triad() {
+  }
+  explicit Triad(T1 t1, T2 t2, T3 t3) : t1(t1), t2(t2), t3(t3) {
+  }
+  T1 first() { return t1; }
+  void print() ;
+  ~Triad() {
+  }
+};
+
+template <typename T1, typename T2, typename T3>
+void Triad<T1, T2, T3>::print() {
+  std::cout << '[' << t1 << ", " << t2 << ", " << t3 << "]\n";
+}
+
+int main() {
+  Triad t1{1, 2, 3};
+  t1.print();
+  std::cout << '\n';
+  std::cout << t1.first() << '\n';
+
+  using namespace std::literals::string_literals;
+  const Triad t2{1, 2.3, "Hello"s};
+  t2.print();
+  std::cout << '\n';
+
+  return 0;
+}

perf-cpp/scripts/ch4.cc

@@ -0,0 +1,38 @@
+/*
+   Write the following program: The user is asked to enter 2 floating point numbers (use doubles). The user is then asked to enter one of the following mathematical symbols: +, -, *, or /. The program computes the answer on the two numbers the user entered and prints the results. If the user enters an invalid symbol, the program should print nothing.
+   */
+
+#include <iostream>
+
+int main() {
+  double x, y;
+  std::cout << "enter x: "<<'\n';
+  std::cin >> x;
+  std::cout << "enter x: "<<'\n';
+  std::cin >> y;
+  std::cout << "enter symbol " << '\n';;
+  char symbol;
+  std::cin >> symbol;
+
+  double ans;
+  switch (symbol) {
+    case '+':
+      ans = x + y;
+      break;
+    case '-':
+      ans = x - y;
+      break;
+    case '*':
+      ans = x * y;
+      break;
+    case '/':
+      ans = x / y;
+      break;
+    default:
+      return 0;
+  }
+
+
+  std::cout << "answer: " << ans << '\n';
+  return 0;
+}

perf-cpp/scripts/ch5.cc

@@ -0,0 +1,51 @@
+#include <cassert>
+#include <cmath>
+#include <concepts>
+#include <iomanip>
+#include <iostream>
+#include <string>
+#include <string_view>
+
+template <std::integral T>
+T binexp(T base, T exponent, T mod) {
+  assert(mod > 0 && exponent > 0);
+
+  T product{1};
+  T multiplier{base % mod};
+
+  while (exponent > 0) {
+    if ((exponent & 1) != 0) {
+      product = (multiplier * product) % mod;
+    }
+    multiplier = (multiplier * multiplier) % mod;
+    exponent >>= 1;
+  }
+
+  return product;
+}
+
+int main() {
+  using namespace std::string_view_literals;
+
+  std::string S{"hello"};
+  std::string_view s{S};
+  S.~basic_string();
+
+  // double ub - free + string view dereferencing destroyed object
+  // std::cout << s << '\n' ;
+
+  std::cout << -5 / 2 << '\n';
+
+  using namespace std;
+  long double ld = pow((long double)10, 18);  // computed in floating point
+  long long ll = (long long)ld;               // cast back to integer
+
+  cout << fixed << setprecision(0);
+  cout << "pow(10,18) as long double: " << ld << "\n";
+  cout << "cast to long long:         " << ll << "\n";
+  cout << "Should be exactly:         " << 1000000000000000000LL << "\n";
+
+  std::cout << binexp(2, 5, 5);
+
+  return 0;
+}

perf-cpp/scripts/ch6.cc

@@ -0,0 +1,20 @@
+#include <iostream>
+#include <cstdint>
+
+/*
+   Write a program that asks the user to input an integer, and tells the user whether the number is even or odd. Write a constexpr function called isEven() that returns true if an integer passed to it is even, and false otherwise. Use the remainder operator to test whether the integer parameter is even. Make sure isEven() works with both positive and negative numbers
+  .*/
+
+constexpr bool isEven(std::int32_t number) {
+  return number % 2 == 0;
+}
+
+int main() {
+  std::cout << "input an integer: \n";
+  std::int32_t x{};
+  std::cin >> x;
+
+  std::cout << std::boolalpha << isEven(x);
+
+  return 0;
+}

perf-cpp/scripts/chapter-1.cc

@@ -0,0 +1,18 @@
+#include <iostream>
+
+int main() {
+  std::cout << "Enter a number: \n";
+
+  int n;
+  std::cin >> n;
+
+  int m;
+
+  std::cout << "Enter another number: \n";
+
+  std::cin >> m;
+
+  std::cout << "Diff: " << n - m << "; Sum: " << n + m << '\n';
+
+  return 0;
+}

perf-cpp/scripts/compile_flags.txt

@@ -0,0 +1,2 @@
+-O0
+-std=c++20

perf-cpp/scripts/consteval.cc

@@ -0,0 +1,14 @@
+#include <iostream>
+
+consteval int foo(int x) {
+  if (x <= 1) return x;
+  return foo(x - 1) + foo(x - 2);
+}
+
+int main() {
+  constexpr int x = foo(3);
+
+  static_assert(x != foo(4));
+
+  return 0;
+}

perf-cpp/scripts/conversion.cc

@@ -0,0 +1,10 @@
+#include <iostream>
+
+void f(double) { std::cout << "double\n"; }
+void f(int)   { std::cout << "long\n"; }
+
+int main() {
+    short x = 5;
+    f(x);   // Which one?
+}
+

perf-cpp/scripts/debug_flags.txt

@@ -0,0 +1,14 @@
+-g3
+-fsanitize=address,undefined
+-fsanitize=float-divide-by-zero
+-fsanitize=float-cast-overflow
+-fno-sanitize-recover=all
+-fstack-protector-all
+-fstack-usage
+-fno-omit-frame-pointer
+-fno-inline
+-ffunction-sections
+-D_GLIBCXX_DEBUG
+-D_GLIBCXX_DEBUG_PEDANTIC
+-DLOCAL
+-std=c++23

perf-cpp/scripts/enum-class-quiz.cc

@@ -0,0 +1,50 @@
+#include <iostream>
+
+struct Counter {
+    inline static int x = 1;
+    static void bump() { ++x; }
+};
+
+struct Counter2 : Counter {
+    inline static int x = 100;
+    static void bump() { x += 10; }
+};
+
+enum E { A = 1, B = 2 };
+
+struct S {
+    enum E { B = 3, C = 4 };
+    static int f() { return B; }
+};
+
+enum class M : unsigned char { A = 250, B, C };
+
+int g() {
+    int B = 40;
+    return S::f() + B;
+}
+
+int main() {
+    Counter::bump();
+    Counter2::bump();
+
+    // 112
+    int t1 = Counter::x + Counter2::x;
+
+    // 43
+    int u1 = g();
+
+    int B = 7;
+    // 9
+    int t2 = B + ::B;
+
+    int d;
+    {
+        using enum M;
+        // 251 - 250 = 1?
+        d = static_cast<int>(B) - static_cast<int>(A);
+    }
+
+    std::cout << t1 << " " << u1 << " " << t2 << " " << d << "\n";
+}
+

perf-cpp/scripts/io/chapter-1.in

@@ -0,0 +1,2 @@
+1
+2

perf-cpp/scripts/io/chapter-1.out

@@ -0,0 +1,7 @@
+Enter a number: 
+Enter another number: 
+Diff: -1; Sum: 3
+
+[code]: 0
+[time]: 2.52771 ms
+[debug]: false

perf-cpp/scripts/io/file.out

@@ -0,0 +1,14 @@
+file.cc: In function ‘int main()’:
+file.cc:66:23: error: narrowing conversion of ‘3.0e+0’ from ‘double’ to ‘int’ [-Wnarrowing]
+   66 |   vector<int> a= { 3.0};
+      |                       ^
+file.cc: At global scope:
+file.cc:39:13: warning: ‘void YES()’ defined but not used [-Wunused-function]
+   39 | static void YES() {
+      |             ^~~
+file.cc:35:13: warning: ‘void NO()’ defined but not used [-Wunused-function]
+   35 | static void NO() {
+      |             ^~
+cc1plus: note: unrecognized command-line option ‘-Wno-sign-promotion’ may have been intended to silence earlier diagnostics
+
+[code]: 1

perf-cpp/scripts/loops.cc

@@ -0,0 +1,32 @@
+
+#include <iostream>
+
+void call_for() {
+  for (int i = 0; i < 5; ++i) {
+    std::cout << (1 + 123 * 6 ^ 3 << 2);
+  }
+}
+
+void call_while() {
+  int i = 0;
+  while (i < 5) {
+    std::cout << (1 + 123 * 6 ^ 3 << 2);
+    ++i;
+  }
+}
+
+void call_do_while() {
+  int i = 0;
+  do {
+    std::cout << (1 + 123 * 6 ^ 3 << 2);
+    ++i;
+  } while (i < 5);
+}
+
+int main() {
+  call_for();
+  call_while();
+  call_do_while();
+
+  return 0;
+}

perf-cpp/scripts/makefile

@@ -0,0 +1,30 @@
+.PHONY: run debug clean setup init
+
+VERSION ?= 20
+
+SRC = $(word 2,$(MAKECMDGOALS))
+
+.SILENT:
+
+run:
+	sh scripts/run.sh $(SRC)
+
+debug:
+	sh scripts/debug.sh $(SRC)
+
+clean:
+	rm -rf build/*
+
+setup:
+	test -d build || mkdir -p build
+	test -d io || mkdir -p io
+	test -d scripts || mkdir -p scripts
+	test -f .clang-format || cp $(HOME)/.config/cp-template/.clang-format .
+	test -f compile_flags.txt || cp $(HOME)/.config/cp-template/compile_flags.txt . && echo -std=c++$(VERSION) >>compile_flags.txt
+	test -f .clangd || cp $(HOME)/.config/cp-template/.clangd . && echo -e "\t\t-std=c++$(VERSION)" >>.clangd
+
+init:
+	make setup
+
+%:
+	@:

perf-cpp/scripts/scripts/debug.sh

@@ -0,0 +1,29 @@
+#!/bin/sh
+
+. ./scripts/utils.sh
+
+SRC="$1"
+BASE=$(basename "$SRC" .cc)
+INPUT="${BASE}.in"
+OUTPUT="${BASE}.out"
+DBG_BIN="${BASE}.debug"
+
+test -d build || mkdir -p build
+test -d io || mkdir -p io
+
+test -f "$INPUT" && test ! -f "io/$INPUT" && mv "$INPUT" "io/"
+test -f "$OUTPUT" && test ! -f "io/$OUTPUT" && mv "$OUTPUT" "io/"
+
+test -f "io/$INPUT" || touch "io/$INPUT"
+test -f "io/$OUTPUT" || touch "io/$OUTPUT"
+
+INPUT="io/$INPUT"
+OUTPUT="io/$OUTPUT"
+DBG_BIN="build/$DBG_BIN"
+
+compile_source "$SRC" "$DBG_BIN" "$OUTPUT" @debug_flags.txt
+CODE=$?
+test $CODE -gt 0 && exit $CODE
+
+execute_binary "$DBG_BIN" "$INPUT" "$OUTPUT" true
+exit $?

perf-cpp/scripts/scripts/run.sh

@@ -0,0 +1,29 @@
+#!/bin/sh
+
+. ./scripts/utils.sh
+
+SRC="$1"
+BASE=$(basename "$SRC" .cc)
+INPUT="${BASE}.in"
+OUTPUT="${BASE}.out"
+RUN_BIN="${BASE}.run"
+
+test -d build || mkdir -p build
+test -d io || mkdir -p io
+
+test -f "$INPUT" && test ! -f "io/$INPUT" && mv "$INPUT" "io/"
+test -f "$OUTPUT" && test ! -f "io/$OUTPUT" && mv "$OUTPUT" "io/"
+
+test -f "io/$INPUT" || touch "io/$INPUT"
+test -f "io/$OUTPUT" || touch "io/$OUTPUT"
+
+INPUT="io/$INPUT"
+OUTPUT="io/$OUTPUT"
+RUN_BIN="build/$RUN_BIN"
+
+compile_source "$SRC" "$RUN_BIN" "$OUTPUT" ""
+CODE=$?
+test $CODE -gt 0 && exit $CODE
+
+execute_binary "$RUN_BIN" "$INPUT" "$OUTPUT"
+exit $?

perf-cpp/scripts/scripts/utils.sh

@@ -0,0 +1,61 @@
+#!/bin/sh
+
+execute_binary() {
+  binary="$1"
+  input="$2"
+  output="$3"
+  is_debug="$4"
+
+  start=$(date '+%s.%N')
+  if [ -n "$is_debug" ]; then
+    asan="$(ldconfig -p | grep libasan.so | head -n1 | awk '{print $4}')"
+    LD_PRELOAD="$asan" timeout 2s ./"$binary" <"$input" >"$output" 2>&1
+  else
+    timeout 2s ./"$binary" <"$input" >"$output" 2>&1
+  fi
+  CODE=$?
+  end=$(date '+%s.%N')
+  truncate -s "$(head -n 1000 "$output" | wc -c)" "$output"
+
+  if [ $CODE -ge 124 ]; then
+    MSG=''
+    case $CODE in
+    124) MSG='TIMEOUT' ;;
+    128) MSG='SIGILL' ;;
+    130) MSG='SIGABRT' ;;
+    131) MSG='SIGBUS' ;;
+    136) MSG='SIGFPE' ;;
+    135) MSG='SIGSEGV' ;;
+    137) MSG='SIGPIPE' ;;
+    139) MSG='SIGTERM' ;;
+    esac
+    [ $CODE -ne 124 ] && sed -i '$d' "$output"
+    test -n "$MSG" && printf '\n[code]: %s (%s)' "$CODE" "$MSG" >>"$output"
+  else
+    printf '\n[code]: %s' "$CODE" >>"$output"
+  fi
+
+  printf '\n[time]: %s ms' "$(awk "BEGIN {print ($end - $start) * 1000}")" >>$output
+  test -n "$is_debug" && is_debug_string=true || is_debug_string=false
+  printf '\n[debug]: %s' "$is_debug_string" >>$output
+  return $CODE
+}
+
+compile_source() {
+  src="$1"
+  bin="$2"
+  output="$3"
+  flags="$4"
+
+  test -f "$bin" && rm "$bin" || true
+  g++ @compile_flags.txt $flags "$src" -o "$bin" 2>"$output"
+  CODE=$?
+
+  if [ $CODE -gt 0 ]; then
+    printf '\n[code]: %s' "$CODE" >>"$output"
+    return $CODE
+  else
+    echo '' >"$output"
+    return 0
+  fi
+}

perf-cpp/scripts/struct.cc

@@ -0,0 +1,40 @@
+#include <iostream>
+
+class S {
+  // void print() const { a = 3; std::cout << S::a << '\n'; }
+  int a = 0;
+
+ public:
+  S(int x) : x(x) {
+  }
+  int x{2};
+};
+
+class X {
+  int x;
+
+ public:
+  X() : x(0) {};
+  void get() {
+    std::cout << "x; " << x << '\n';
+  }
+  int& y() {
+    return x;
+  }
+};
+
+int main() {
+  // S{}.print();
+  // S.x;
+  // std::cout << S{3}.x << '\n';
+
+  X x;
+  auto& ret = x.y();
+
+  // ++ret;
+
+  x.get();
+
+  // X x;
+  return 0;
+}

perf-cpp/scripts/switch.cc

@@ -0,0 +1,39 @@
+#include <iostream>
+
+extern volatile int sink;
+
+int g(int x) {
+  if      (x == 100) sink = 42;
+  else if (x == 101) sink = 7;
+  else if (x == 102) sink = 99;
+  else if (x == 103) sink = 13;
+  else if (x == 104) sink = 5;
+  else if (x == 105) sink = 88;
+  else if (x == 106) sink = 21;
+  else if (x == 107) sink = 60;
+  else if (x == 108) sink = 33;
+  else if (x == 109) sink = 1;
+  else if (x == 110) sink = 77;
+  else if (x == 111) sink = 12;
+  else if (x == 112) sink = 54;
+  else if (x == 113) sink = 31;
+  else if (x == 114) sink = 73;
+  else if (x == 115) sink = 16;
+  else               sink = -1;
+  return sink;
+}
+
+int main() {
+  char x;
+  std::cin >> x;
+
+  if (x == 'x') {
+    std::cout << "hi\n";
+  } else {
+    if (x == 'y') {
+      std::cout << "sup\n";
+    }
+  }
+
+  return 0;
+}