Added negative exhaustive test

Author: meltq

libc/test/src/math/exhaustive/hypotf16_test.cpp

@@ -15,20 +15,17 @@
 
 namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
 
-// Range of both inputs: [0, inf]
-static constexpr uint16_t START = 0x0000U;
-static constexpr uint16_t STOP = 0x7C00U;
-
 struct Hypotf16Checker : public virtual LIBC_NAMESPACE::testing::Test {
   using FloatType = float16;
   using FPBits = LIBC_NAMESPACE::fputil::FPBits<float16>;
   using StorageType = typename FPBits::StorageType;
 
-  uint64_t check(uint16_t start, uint16_t stop, mpfr::RoundingMode rounding) {
+  uint64_t check(uint16_t x_start, uint16_t x_stop, uint16_t y_start,
+                 uint16_t y_stop, mpfr::RoundingMode rounding) {
     mpfr::ForceRoundingMode r(rounding);
     if (!r.success)
       return true;
-    uint16_t xbits = start;
+    uint16_t xbits = x_start;
     uint64_t failed = 0;
     do {
       float16 x = FPBits(xbits).get_val();
@@ -44,15 +41,27 @@ struct Hypotf16Checker : public virtual LIBC_NAMESPACE::testing::Test {
         // 0.5,
         //  rounding);
         failed += (!correct);
-      } while (ybits++ < STOP);
-    } while (xbits++ < stop);
+      } while (ybits++ < y_stop);
+    } while (xbits++ < x_stop);
     return failed;
   }
 };
 
 using LlvmLibcHypotf16ExhaustiveTest =
     LlvmLibcExhaustiveMathTest<Hypotf16Checker, 1 << 2>;
 
+// Range of both inputs: [0, inf]
+static constexpr uint16_t POS_START = 0x0000U;
+static constexpr uint16_t POS_STOP = 0x7C00U;
+
 TEST_F(LlvmLibcHypotf16ExhaustiveTest, PositiveRange) {
-  test_full_range_all_roundings(START, STOP);
+  test_full_range_all_roundings(POS_START, POS_STOP, POS_START, POS_STOP);
+}
+
+// Range of both inputs: [-0, -inf]
+static constexpr uint16_t NEG_START = 0x8000U;
+static constexpr uint16_t NEG_STOP = 0xFC00U;
+
+TEST_F(LlvmLibcHypotf16ExhaustiveTest, NegativeRange) {
+  test_full_range_all_roundings(NEG_START, NEG_STOP, NEG_START, NEG_STOP);
 }