[libc][math][c23] Fix totalorder and totalordermag smoke tests

[overmighty]

FPBits::signaling_nan() defaults to setting the MSB of the payload to 1.
The tests also used signaling NaNs with a payload of 0x123. With
float16, the 1 in 0x123 aligns to the MSB of the payload, therefore
0x123 is greater than the default payload. However, that is not the case
with more precise floating-point types.

[llvmbot]

@llvm/pr-subscribers-libc

Author: OverMighty (overmighty)

Changes

FPBits::signaling_nan() defaults to setting the MSB of the payload to 1.
The tests also used signaling NaNs with a payload of 0x123. With
float16, the 1 in 0x123 aligns to the MSB of the payload, therefore
0x123 is greater than the default payload. However, that is not the case
with more precise floating-point types.

---

Full diff: https://github.com/llvm/llvm-project/pull/100354.diff

2 Files Affected:

• (modified) libc/test/src/math/smoke/TotalOrderMagTest.h (+12-12)
• (modified) libc/test/src/math/smoke/TotalOrderTest.h (+12-12)

diff --git a/libc/test/src/math/smoke/TotalOrderMagTest.h b/libc/test/src/math/smoke/TotalOrderMagTest.h
index 5fe2983a0e678..3d7f24fc74d10 100644
--- a/libc/test/src/math/smoke/TotalOrderMagTest.h
+++ b/libc/test/src/math/smoke/TotalOrderMagTest.h
@@ -104,24 +104,24 @@ class TotalOrderMagTestTemplate : public LIBC_NAMESPACE::testing::FEnvSafeTest {
   }
 
   void testNaNPayloads(TotalOrderMagFunc func) {
-    T qnan_123 = FPBits::quiet_nan(Sign::POS, 0x123).get_val();
-    T neg_qnan_123 = FPBits::quiet_nan(Sign::NEG, 0x123).get_val();
-    T snan_123 = FPBits::signaling_nan(Sign::POS, 0x123).get_val();
-    T neg_snan_123 = FPBits::signaling_nan(Sign::NEG, 0x123).get_val();
+    T qnan_0x42 = FPBits::quiet_nan(Sign::POS, 0x42).get_val();
+    T neg_qnan_0x42 = FPBits::quiet_nan(Sign::NEG, 0x42).get_val();
+    T snan_0x42 = FPBits::signaling_nan(Sign::POS, 0x42).get_val();
+    T neg_snan_0x42 = FPBits::signaling_nan(Sign::NEG, 0x42).get_val();
 
     EXPECT_TRUE(funcWrapper(func, aNaN, aNaN));
     EXPECT_TRUE(funcWrapper(func, sNaN, sNaN));
-    EXPECT_TRUE(funcWrapper(func, aNaN, qnan_123));
-    EXPECT_TRUE(funcWrapper(func, sNaN, snan_123));
-    EXPECT_FALSE(funcWrapper(func, qnan_123, aNaN));
-    EXPECT_FALSE(funcWrapper(func, snan_123, sNaN));
+    EXPECT_TRUE(funcWrapper(func, aNaN, qnan_0x42));
+    EXPECT_FALSE(funcWrapper(func, sNaN, snan_0x42));
+    EXPECT_FALSE(funcWrapper(func, qnan_0x42, aNaN));
+    EXPECT_TRUE(funcWrapper(func, snan_0x42, sNaN));
 
     EXPECT_TRUE(funcWrapper(func, neg_aNaN, neg_aNaN));
     EXPECT_TRUE(funcWrapper(func, neg_sNaN, neg_sNaN));
-    EXPECT_TRUE(funcWrapper(func, neg_aNaN, neg_qnan_123));
-    EXPECT_TRUE(funcWrapper(func, neg_sNaN, neg_snan_123));
-    EXPECT_FALSE(funcWrapper(func, neg_qnan_123, neg_aNaN));
-    EXPECT_FALSE(funcWrapper(func, neg_snan_123, neg_sNaN));
+    EXPECT_TRUE(funcWrapper(func, neg_aNaN, neg_qnan_0x42));
+    EXPECT_FALSE(funcWrapper(func, neg_sNaN, neg_snan_0x42));
+    EXPECT_FALSE(funcWrapper(func, neg_qnan_0x42, neg_aNaN));
+    EXPECT_TRUE(funcWrapper(func, neg_snan_0x42, neg_sNaN));
   }
 };
 
diff --git a/libc/test/src/math/smoke/TotalOrderTest.h b/libc/test/src/math/smoke/TotalOrderTest.h
index 281b2a59f930d..4d4257d089daf 100644
--- a/libc/test/src/math/smoke/TotalOrderTest.h
+++ b/libc/test/src/math/smoke/TotalOrderTest.h
@@ -102,24 +102,24 @@ class TotalOrderTestTemplate : public LIBC_NAMESPACE::testing::FEnvSafeTest {
   }
 
   void testNaNPayloads(TotalOrderFunc func) {
-    T qnan_123 = FPBits::quiet_nan(Sign::POS, 0x123).get_val();
-    T neg_qnan_123 = FPBits::quiet_nan(Sign::NEG, 0x123).get_val();
-    T snan_123 = FPBits::signaling_nan(Sign::POS, 0x123).get_val();
-    T neg_snan_123 = FPBits::signaling_nan(Sign::NEG, 0x123).get_val();
+    T qnan_0x42 = FPBits::quiet_nan(Sign::POS, 0x42).get_val();
+    T neg_qnan_0x42 = FPBits::quiet_nan(Sign::NEG, 0x42).get_val();
+    T snan_0x42 = FPBits::signaling_nan(Sign::POS, 0x42).get_val();
+    T neg_snan_0x42 = FPBits::signaling_nan(Sign::NEG, 0x42).get_val();
 
     EXPECT_TRUE(funcWrapper(func, aNaN, aNaN));
     EXPECT_TRUE(funcWrapper(func, sNaN, sNaN));
-    EXPECT_TRUE(funcWrapper(func, aNaN, qnan_123));
-    EXPECT_TRUE(funcWrapper(func, sNaN, snan_123));
-    EXPECT_FALSE(funcWrapper(func, qnan_123, aNaN));
-    EXPECT_FALSE(funcWrapper(func, snan_123, sNaN));
+    EXPECT_TRUE(funcWrapper(func, aNaN, qnan_0x42));
+    EXPECT_FALSE(funcWrapper(func, sNaN, snan_0x42));
+    EXPECT_FALSE(funcWrapper(func, qnan_0x42, aNaN));
+    EXPECT_TRUE(funcWrapper(func, snan_0x42, sNaN));
 
     EXPECT_TRUE(funcWrapper(func, neg_aNaN, neg_aNaN));
     EXPECT_TRUE(funcWrapper(func, neg_sNaN, neg_sNaN));
-    EXPECT_FALSE(funcWrapper(func, neg_aNaN, neg_qnan_123));
-    EXPECT_FALSE(funcWrapper(func, neg_sNaN, neg_snan_123));
-    EXPECT_TRUE(funcWrapper(func, neg_qnan_123, neg_aNaN));
-    EXPECT_TRUE(funcWrapper(func, neg_snan_123, neg_sNaN));
+    EXPECT_FALSE(funcWrapper(func, neg_aNaN, neg_qnan_0x42));
+    EXPECT_TRUE(funcWrapper(func, neg_sNaN, neg_snan_0x42));
+    EXPECT_TRUE(funcWrapper(func, neg_qnan_0x42, neg_aNaN));
+    EXPECT_FALSE(funcWrapper(func, neg_snan_0x42, neg_sNaN));
   }
 };