Add more sophisticated test for destruction order of C++ temporaries, please

feel free to extend!

llvm-svn: 90143

clang/test/CodeGenCXX/temp-order.cpp

@@ -0,0 +1,133 @@
+// Output file should have no calls to error() with folding.
+// RUN: clang-cc -triple i386-unknown-unknown -O3 -emit-llvm -o %t %s
+// RUN: FileCheck %s < %t
+
+static unsigned pow(unsigned Base, unsigned Power) {
+  unsigned Val = 1;
+  while (Power--)
+    Val *= Base;
+  return Val;
+}
+
+struct TempTracker {
+  unsigned Product, Index;
+
+  TempTracker() : Product(1), Index(0) {}
+
+};
+
+// FIXME: This can be used to check elision as well, if P = 0 hacks are removed.
+struct A {
+  TempTracker &TT;
+  mutable unsigned P;
+  bool Truth;
+
+  A(TempTracker &_TT, unsigned _P, bool _Truth = true)
+    : TT(_TT), P(_P), Truth(_Truth) {}
+  A(const A &RHS) : TT(RHS.TT), P(RHS.P), Truth(RHS.Truth) { RHS.P = 0; }
+  ~A() {
+    if (P)
+      TT.Product *= pow(P, ++TT.Index);
+  }
+
+  operator bool () { return Truth; }
+};
+
+// 3, 7, 2
+static unsigned f0(bool val = false) {
+  TempTracker tt;
+  {
+    A a(tt, 2);
+    if ((A(tt, 3), val))
+      A b(tt, 5);
+    A c(tt, 7);
+  }
+  return tt.Product;
+}
+
+// 3, 5, 7, 2
+static unsigned f1(bool val = true) {
+  TempTracker tt;
+  {
+    A a(tt, 2);
+    if ((A(tt, 3), val))
+      A b(tt, 5);
+    A c(tt, 7);
+  }
+  return tt.Product;
+}
+
+// 5, 3, 7, 2
+static unsigned f2() {
+  TempTracker tt;
+  {
+    A a(tt, 2);
+    if (A b = A(tt, 3))
+      A c(tt, 5);
+    A d(tt, 7);
+  }
+  return tt.Product;
+}
+
+// 7, 3, 11, 2
+static unsigned f3() {
+  TempTracker tt;
+  {
+    A a(tt, 2);
+    if (A b = A(tt, 3, false))
+      A c(tt, 5);
+    else
+      A c(tt, 7);
+    A d(tt, 11);
+  }
+  return tt.Product;
+}
+
+extern "C" void error();
+extern "C" void print(const char *Name, unsigned N);
+
+#define ORDER3(a, b, c) (pow(a, 1) * pow(b, 2) * pow(c, 3))
+#define ORDER4(a, b, c, d) (ORDER3(a, b, c) * pow(d, 4))
+void test() {
+// CHECK: call void @print(i8* {{.*}}, i32 1176)
+  print("f0", f0());
+  if (f0() != ORDER3(3, 7, 2))
+    error();
+
+// CHECK: call void @print(i8* {{.*}}, i32 411600)
+  print("f1", f1());
+  if (f1() != ORDER4(3, 5, 7, 2))
+    error();
+
+// CHECK: call void @print(i8* {{.*}}, i32 246960)
+  print("f2", f2());
+  if (f2() != ORDER4(5, 3, 7, 2))
+    error();
+
+// CHECK: call void @print(i8* {{.*}}, i32 1341648)
+  print("f3", f3());
+  if (f3() != ORDER4(7, 3, 11, 2))
+    error();
+}
+
+
+
+#ifdef HARNESS
+
+#include <cstdlib>
+#include <cstdio>
+
+extern "C" void error() {
+  abort();
+}
+
+extern "C" void print(const char *name, unsigned N) {
+  printf("%s: %d\n", name, N);
+}
+
+int main() {
+  test();
+  return 0;
+}
+
+#endif