diff options
| -rw-r--r-- | library/std/src/f32/tests.rs | 24 | ||||
| -rw-r--r-- | library/std/src/f64/tests.rs | 24 |
2 files changed, 36 insertions, 12 deletions
diff --git a/library/std/src/f32/tests.rs b/library/std/src/f32/tests.rs index 07b9ff3a789..7a2f9bd4878 100644 --- a/library/std/src/f32/tests.rs +++ b/library/std/src/f32/tests.rs @@ -308,12 +308,18 @@ fn test_next_up() { let smallest_normal = f32::from_bits(0x0080_0000); // Check that NaNs roundtrip. + // Because x87 can lose NaN bits when passed through a function, ensure the reference value + // also passes through a function boundary. + #[inline(never)] + fn identity(x: f32) -> f32 { + crate::hint::black_box(x) + } let nan0 = f32::NAN; let nan1 = f32::from_bits(f32::NAN.to_bits() ^ 0x002a_aaaa); let nan2 = f32::from_bits(f32::NAN.to_bits() ^ 0x0055_5555); - assert_eq!(nan0.next_up().to_bits(), nan0.to_bits()); - assert_eq!(nan1.next_up().to_bits(), nan1.to_bits()); - assert_eq!(nan2.next_up().to_bits(), nan2.to_bits()); + assert_eq!(nan0.next_up().to_bits(), identity(nan0).to_bits()); + assert_eq!(nan1.next_up().to_bits(), identity(nan1).to_bits()); + assert_eq!(nan2.next_up().to_bits(), identity(nan2).to_bits()); assert_eq!(f32::NEG_INFINITY.next_up(), f32::MIN); assert_eq!(f32::MIN.next_up(), -max_down); @@ -339,12 +345,18 @@ fn test_next_down() { let smallest_normal = f32::from_bits(0x0080_0000); // Check that NaNs roundtrip. + // Because x87 can lose NaN bits when passed through a function, ensure the reference value + // also passes through a function boundary. + #[inline(never)] + fn identity(x: f32) -> f32 { + crate::hint::black_box(x) + } let nan0 = f32::NAN; let nan1 = f32::from_bits(f32::NAN.to_bits() ^ 0x002a_aaaa); let nan2 = f32::from_bits(f32::NAN.to_bits() ^ 0x0055_5555); - assert_eq!(nan0.next_down().to_bits(), nan0.to_bits()); - assert_eq!(nan1.next_down().to_bits(), nan1.to_bits()); - assert_eq!(nan2.next_down().to_bits(), nan2.to_bits()); + assert_eq!(nan0.next_down().to_bits(), identity(nan0).to_bits()); + assert_eq!(nan1.next_down().to_bits(), identity(nan1).to_bits()); + assert_eq!(nan2.next_down().to_bits(), identity(nan2).to_bits()); assert_eq!(f32::NEG_INFINITY.next_down(), f32::NEG_INFINITY); assert_eq!(f32::MIN.next_down(), f32::NEG_INFINITY); diff --git a/library/std/src/f64/tests.rs b/library/std/src/f64/tests.rs index cf46ffcffcf..2524bfe8b99 100644 --- a/library/std/src/f64/tests.rs +++ b/library/std/src/f64/tests.rs @@ -298,12 +298,18 @@ fn test_next_up() { let smallest_normal = f64::from_bits(0x0010_0000_0000_0000); // Check that NaNs roundtrip. + // Because x87 can lose NaN bits when passed through a function, ensure the reference value + // also passes through a function boundary. + #[inline(never)] + fn identity(x: f64) -> f64 { + crate::hint::black_box(x) + } let nan0 = f64::NAN; let nan1 = f64::from_bits(f64::NAN.to_bits() ^ 0x000a_aaaa_aaaa_aaaa); let nan2 = f64::from_bits(f64::NAN.to_bits() ^ 0x0005_5555_5555_5555); - assert_eq!(nan0.next_up().to_bits(), nan0.to_bits()); - assert_eq!(nan1.next_up().to_bits(), nan1.to_bits()); - assert_eq!(nan2.next_up().to_bits(), nan2.to_bits()); + assert_eq!(nan0.next_up().to_bits(), identity(nan0).to_bits()); + assert_eq!(nan1.next_up().to_bits(), identity(nan1).to_bits()); + assert_eq!(nan2.next_up().to_bits(), identity(nan2).to_bits()); assert_eq!(f64::NEG_INFINITY.next_up(), f64::MIN); assert_eq!(f64::MIN.next_up(), -max_down); @@ -329,12 +335,18 @@ fn test_next_down() { let smallest_normal = f64::from_bits(0x0010_0000_0000_0000); // Check that NaNs roundtrip. + // Because x87 can lose NaN bits when passed through a function, ensure the reference value + // also passes through a function boundary. + #[inline(never)] + fn identity(x: f64) -> f64 { + crate::hint::black_box(x) + } let nan0 = f64::NAN; let nan1 = f64::from_bits(f64::NAN.to_bits() ^ 0x000a_aaaa_aaaa_aaaa); let nan2 = f64::from_bits(f64::NAN.to_bits() ^ 0x0005_5555_5555_5555); - assert_eq!(nan0.next_down().to_bits(), nan0.to_bits()); - assert_eq!(nan1.next_down().to_bits(), nan1.to_bits()); - assert_eq!(nan2.next_down().to_bits(), nan2.to_bits()); + assert_eq!(nan0.next_down().to_bits(), identity(nan0).to_bits()); + assert_eq!(nan1.next_down().to_bits(), identity(nan1).to_bits()); + assert_eq!(nan2.next_down().to_bits(), identity(nan2).to_bits()); assert_eq!(f64::NEG_INFINITY.next_down(), f64::NEG_INFINITY); assert_eq!(f64::MIN.next_down(), f64::NEG_INFINITY); |