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// 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);
}
A &operator=(const A &RHS) {
TT = RHS.TT;
P = RHS.P;
Truth = RHS.Truth;
RHS.P = 0;
return *this;
}
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;
}
// 3, 7, 2
static unsigned f4() {
TempTracker tt;
{
A a(tt, 2);
while (A b = A(tt, 3, false))
A c(tt, 5);
A c(tt, 7);
}
return tt.Product;
}
// 5, 3, 7, 2
static unsigned f5() {
TempTracker tt;
{
A a(tt, 2);
while (A b = A(tt, 3, true)) {
A c(tt, 5);
break;
}
A c(tt, 7);
}
return tt.Product;
}
// 3, 7, 11, 5, 13, 2
static unsigned f6() {
TempTracker tt;
{
A a(tt, 2);
for (A b = (A(tt, 3), A(tt, 5)), c = (A(tt, 7), A(tt, 11));;)
break;
A c(tt, 13);
}
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))
#define ORDER5(a, b, c, d, e) (ORDER4(a, b, c, d) * pow(e, 5))
#define ORDER6(a, b, c, d, e, f) (ORDER5(a, b, c, d, e) * pow(f, 6))
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();
// CHECK: call void @print(i8* {{.*}}, i32 1176)
print("f4", f4());
if (f4() != ORDER3(3, 7, 2))
error();
// CHECK: call void @print(i8* {{.*}}, i32 246960)
print("f5", f5());
if (f5() != ORDER4(5, 3, 7, 2))
error();
// FIXME: Clang/LLVM currently can't fold this to a constant. If the error check
// is present (since it avoids single-caller inlining). PR5645.
// CHECK: call void @print(i8* {{.*}}, i32 1251552576)
print("f6", f6());
// if (f6() != ORDER6(3, 7, 11, 5, 13, 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
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