Resolve integer overflow warnings in GCD and LCM tests

lcm.pass.cpp:
19: Update headers to that actually used in the test.
41: test0 was triggering narrowing warnings for all callers, because the
inputs were always ints, but some of the explicit template arguments were
smaller than that. Instead, have this function accept ints and static_cast
explicitly to the types we want before calling std::lcm.
47: Replace unnecessary ternary.
55: Use foo_t instead of typename foo<>::type
111/116: intX_t were not std::qualified but only <cfoo> headers were included.
141: C1XX has a bug where it interprets 2147483648 as unsigned int. Then the
negation trips "negation of unsigned value, result still unsigned" warnings.
Perma-workaround this issue by saying INT_MIN, which better documents the
intended behavior and avoids triggering warnings on C1XX.

gcd.pass.cpp:
Same changes as lcm.pass.cpp but for GCD.

llvm-svn: 302472

1 files changed, 27 insertions, 22 deletions

diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.pass.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.pass.cpp
index 90d48398f54..6bd8a4f1e61 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.pass.cpp
@@ -11,12 +11,14 @@
 // <numeric>
 
 // template<class _M, class _N>
-// constexpr common_type_t<_M,_N> gcd(_M __m, _N __n)
+// constexpr common_type_t<_M,_N> lcm(_M __m, _N __n)
 
 #include <numeric>
 #include <cassert>
+#include <climits>
+#include <cstdint>
 #include <cstdlib>
-#include <iostream>
+#include <type_traits>
 
 constexpr struct {
   int x;
@@ -34,21 +36,24 @@ constexpr struct {
 };
 
 template <typename Input1, typename Input2, typename Output>
-constexpr bool test0(Input1 in1, Input2 in2, Output out)
+constexpr bool test0(int in1, int in2, int out)
 {
-    static_assert((std::is_same<Output, decltype(std::lcm(Input1(0), Input2(0)))>::value), "" );
-    static_assert((std::is_same<Output, decltype(std::lcm(Input2(0), Input1(0)))>::value), "" );
-    return out == std::lcm(in1, in2) ? true : (std::abort(), false);
+    auto value1 = static_cast<Input1>(in1);
+    auto value2 = static_cast<Input2>(in2);
+    static_assert(std::is_same_v<Output, decltype(std::lcm(value1, value2))>, "");
+    static_assert(std::is_same_v<Output, decltype(std::lcm(value2, value1))>, "");
+    assert(static_cast<Output>(out) == std::lcm(value1, value2));
+    return true;
 }
 
 
 template <typename Input1, typename Input2 = Input1>
 constexpr bool do_test(int = 0)
 {
-    using S1 = typename std::make_signed<Input1>::type;
-    using S2 = typename std::make_signed<Input2>::type;
-    using U1 = typename std::make_unsigned<Input1>::type;
-    using U2 = typename std::make_unsigned<Input2>::type;
+    using S1 = std::make_signed_t<Input1>;
+    using S2 = std::make_signed_t<Input2>;
+    using U1 = std::make_unsigned_t<Input1>;
+    using U2 = std::make_unsigned_t<Input2>;
     bool accumulate = true;
     for (auto TC : Cases) {
         { // Test with two signed types
@@ -101,15 +106,15 @@ int main()
     assert(do_test<long>(non_cce));
     assert(do_test<long long>(non_cce));
 
-    static_assert(do_test< int8_t>(), "");
-    static_assert(do_test<int16_t>(), "");
-    static_assert(do_test<int32_t>(), "");
-    static_assert(do_test<int64_t>(), "");
+    static_assert(do_test<std::int8_t>(), "");
+    static_assert(do_test<std::int16_t>(), "");
+    static_assert(do_test<std::int32_t>(), "");
+    static_assert(do_test<std::int64_t>(), "");
 
-    assert(do_test< int8_t>(non_cce));
-    assert(do_test<int16_t>(non_cce));
-    assert(do_test<int32_t>(non_cce));
-    assert(do_test<int64_t>(non_cce));
+    assert(do_test<std::int8_t>(non_cce));
+    assert(do_test<std::int16_t>(non_cce));
+    assert(do_test<std::int32_t>(non_cce));
+    assert(do_test<std::int64_t>(non_cce));
 
     static_assert(do_test<signed char, int>(), "");
     static_assert(do_test<int, signed char>(), "");
@@ -131,9 +136,9 @@ int main()
 
 //  LWG#2837
     {
-    auto res1 = std::lcm((int64_t)1234, (int32_t)-2147483648);
-    (void) std::lcm<int, unsigned long>(INT_MIN, 2);	// this used to trigger UBSAN
-    static_assert( std::is_same<decltype(res1), std::common_type<int64_t, int32_t>::type>::value, "");
-	assert(res1 == 1324997410816LL);
+    auto res1 = std::lcm(static_cast<std::int64_t>(1234), INT32_MIN);
+    (void)std::lcm(INT_MIN, 2UL);	// this used to trigger UBSAN
+    static_assert(std::is_same_v<decltype(res1), std::int64_t>, "");
+    assert(res1 == 1324997410816LL);
     }
 }