Add intrinsic fallback for `{minimum,maximum}{16,32,64,128}`

5 files changed, 108 insertions, 164 deletions

diff --git a/library/core/src/intrinsics/mod.rs b/library/core/src/intrinsics/mod.rs
index 002ef418ae2..d0708923583 100644
--- a/library/core/src/intrinsics/mod.rs
+++ b/library/core/src/intrinsics/mod.rs
@@ -3989,9 +3989,19 @@ pub const fn minnumf128(x: f128, y: f128) -> f128;
 /// Therefore, implementations must not require the user to uphold
 /// any safety invariants.
 #[rustc_nounwind]
-#[rustc_intrinsic]
-#[cfg(not(bootstrap))]
-pub const fn minimumf16(x: f16, y: f16) -> f16;
+#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+pub const fn minimumf16(x: f16, y: f16) -> f16 {
+    if x < y {
+        x
+    } else if y < x {
+        y
+    } else if x == y {
+        if x.is_sign_negative() && y.is_sign_positive() { x } else { y }
+    } else {
+        // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
+        x + y
+    }
+}
 
 /// Returns the minimum (IEEE 754-2019 minimum) of two `f32` values.
 ///
@@ -4000,9 +4010,19 @@ pub const fn minimumf16(x: f16, y: f16) -> f16;
 /// Therefore, implementations must not require the user to uphold
 /// any safety invariants.
 #[rustc_nounwind]
-#[rustc_intrinsic]
-#[cfg(not(bootstrap))]
-pub const fn minimumf32(x: f32, y: f32) -> f32;
+#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+pub const fn minimumf32(x: f32, y: f32) -> f32 {
+    if x < y {
+        x
+    } else if y < x {
+        y
+    } else if x == y {
+        if x.is_sign_negative() && y.is_sign_positive() { x } else { y }
+    } else {
+        // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
+        x + y
+    }
+}
 
 /// Returns the minimum (IEEE 754-2019 minimum) of two `f64` values.
 ///
@@ -4011,9 +4031,19 @@ pub const fn minimumf32(x: f32, y: f32) -> f32;
 /// Therefore, implementations must not require the user to uphold
 /// any safety invariants.
 #[rustc_nounwind]
-#[rustc_intrinsic]
-#[cfg(not(bootstrap))]
-pub const fn minimumf64(x: f64, y: f64) -> f64;
+#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+pub const fn minimumf64(x: f64, y: f64) -> f64 {
+    if x < y {
+        x
+    } else if y < x {
+        y
+    } else if x == y {
+        if x.is_sign_negative() && y.is_sign_positive() { x } else { y }
+    } else {
+        // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
+        x + y
+    }
+}
 
 /// Returns the minimum (IEEE 754-2019 minimum) of two `f128` values.
 ///
@@ -4022,9 +4052,19 @@ pub const fn minimumf64(x: f64, y: f64) -> f64;
 /// Therefore, implementations must not require the user to uphold
 /// any safety invariants.
 #[rustc_nounwind]
-#[rustc_intrinsic]
-#[cfg(not(bootstrap))]
-pub const fn minimumf128(x: f128, y: f128) -> f128;
+#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+pub const fn minimumf128(x: f128, y: f128) -> f128 {
+    if x < y {
+        x
+    } else if y < x {
+        y
+    } else if x == y {
+        if x.is_sign_negative() && y.is_sign_positive() { x } else { y }
+    } else {
+        // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
+        x + y
+    }
+}
 
 /// Returns the maximum (IEEE 754-2008 maxNum) of two `f16` values.
 ///
@@ -4087,9 +4127,18 @@ pub const fn maxnumf128(x: f128, y: f128) -> f128;
 /// Therefore, implementations must not require the user to uphold
 /// any safety invariants.
 #[rustc_nounwind]
-#[rustc_intrinsic]
-#[cfg(not(bootstrap))]
-pub const fn maximumf16(x: f16, y: f16) -> f16;
+#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+pub const fn maximumf16(x: f16, y: f16) -> f16 {
+    if x > y {
+        x
+    } else if y > x {
+        y
+    } else if x == y {
+        if x.is_sign_positive() && y.is_sign_negative() { x } else { y }
+    } else {
+        x + y
+    }
+}
 
 /// Returns the maximum (IEEE 754-2019 maximum) of two `f32` values.
 ///
@@ -4098,9 +4147,18 @@ pub const fn maximumf16(x: f16, y: f16) -> f16;
 /// Therefore, implementations must not require the user to uphold
 /// any safety invariants.
 #[rustc_nounwind]
-#[rustc_intrinsic]
-#[cfg(not(bootstrap))]
-pub const fn maximumf32(x: f32, y: f32) -> f32;
+#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+pub const fn maximumf32(x: f32, y: f32) -> f32 {
+    if x > y {
+        x
+    } else if y > x {
+        y
+    } else if x == y {
+        if x.is_sign_positive() && y.is_sign_negative() { x } else { y }
+    } else {
+        x + y
+    }
+}
 
 /// Returns the maximum (IEEE 754-2019 maximum) of two `f64` values.
 ///
@@ -4109,9 +4167,18 @@ pub const fn maximumf32(x: f32, y: f32) -> f32;
 /// Therefore, implementations must not require the user to uphold
 /// any safety invariants.
 #[rustc_nounwind]
-#[rustc_intrinsic]
-#[cfg(not(bootstrap))]
-pub const fn maximumf64(x: f64, y: f64) -> f64;
+#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+pub const fn maximumf64(x: f64, y: f64) -> f64 {
+    if x > y {
+        x
+    } else if y > x {
+        y
+    } else if x == y {
+        if x.is_sign_positive() && y.is_sign_negative() { x } else { y }
+    } else {
+        x + y
+    }
+}
 
 /// Returns the maximum (IEEE 754-2019 maximum) of two `f128` values.
 ///
@@ -4120,9 +4187,18 @@ pub const fn maximumf64(x: f64, y: f64) -> f64;
 /// Therefore, implementations must not require the user to uphold
 /// any safety invariants.
 #[rustc_nounwind]
-#[rustc_intrinsic]
-#[cfg(not(bootstrap))]
-pub const fn maximumf128(x: f128, y: f128) -> f128;
+#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+pub const fn maximumf128(x: f128, y: f128) -> f128 {
+    if x > y {
+        x
+    } else if y > x {
+        y
+    } else if x == y {
+        if x.is_sign_positive() && y.is_sign_negative() { x } else { y }
+    } else {
+        x + y
+    }
+}
 
 /// Returns the absolute value of an `f16`.
 ///
diff --git a/library/core/src/num/f128.rs b/library/core/src/num/f128.rs
index 97e24a19ea6..8020b36c6fa 100644
--- a/library/core/src/num/f128.rs
+++ b/library/core/src/num/f128.rs
@@ -755,25 +755,9 @@ impl f128 {
     #[inline]
     #[unstable(feature = "f128", issue = "116909")]
     // #[unstable(feature = "float_minimum_maximum", issue = "91079")]
-    #[rustc_const_unstable(feature = "f128", issue = "116909")]
     #[must_use = "this returns the result of the comparison, without modifying either input"]
     pub const fn maximum(self, other: f128) -> f128 {
-        #[cfg(not(bootstrap))]
-        {
-            intrinsics::maximumf128(self, other)
-        }
-        #[cfg(bootstrap)]
-        {
-            if self > other {
-                self
-            } else if other > self {
-                other
-            } else if self == other {
-                if self.is_sign_positive() && other.is_sign_negative() { self } else { other }
-            } else {
-                self + other
-            }
-        }
+        intrinsics::maximumf128(self, other)
     }
 
     /// Returns the minimum of the two numbers, propagating NaN.
@@ -804,26 +788,9 @@ impl f128 {
     #[inline]
     #[unstable(feature = "f128", issue = "116909")]
     // #[unstable(feature = "float_minimum_maximum", issue = "91079")]
-    #[rustc_const_unstable(feature = "f128", issue = "116909")]
     #[must_use = "this returns the result of the comparison, without modifying either input"]
     pub const fn minimum(self, other: f128) -> f128 {
-        #[cfg(not(bootstrap))]
-        {
-            intrinsics::minimumf128(self, other)
-        }
-        #[cfg(bootstrap)]
-        {
-            if self < other {
-                self
-            } else if other < self {
-                other
-            } else if self == other {
-                if self.is_sign_negative() && other.is_sign_positive() { self } else { other }
-            } else {
-                // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
-                self + other
-            }
-        }
+        intrinsics::minimumf128(self, other)
     }
 
     /// Calculates the midpoint (average) between `self` and `rhs`.
diff --git a/library/core/src/num/f16.rs b/library/core/src/num/f16.rs
index d3af78123c8..68201400a1d 100644
--- a/library/core/src/num/f16.rs
+++ b/library/core/src/num/f16.rs
@@ -744,25 +744,9 @@ impl f16 {
     #[inline]
     #[unstable(feature = "f16", issue = "116909")]
     // #[unstable(feature = "float_minimum_maximum", issue = "91079")]
-    #[rustc_const_unstable(feature = "f16", issue = "116909")]
     #[must_use = "this returns the result of the comparison, without modifying either input"]
     pub const fn maximum(self, other: f16) -> f16 {
-        #[cfg(not(bootstrap))]
-        {
-            intrinsics::maximumf16(self, other)
-        }
-        #[cfg(bootstrap)]
-        {
-            if self > other {
-                self
-            } else if other > self {
-                other
-            } else if self == other {
-                if self.is_sign_positive() && other.is_sign_negative() { self } else { other }
-            } else {
-                self + other
-            }
-        }
+        intrinsics::maximumf16(self, other)
     }
 
     /// Returns the minimum of the two numbers, propagating NaN.
@@ -792,26 +776,9 @@ impl f16 {
     #[inline]
     #[unstable(feature = "f16", issue = "116909")]
     // #[unstable(feature = "float_minimum_maximum", issue = "91079")]
-    #[rustc_const_unstable(feature = "f16", issue = "116909")]
     #[must_use = "this returns the result of the comparison, without modifying either input"]
     pub const fn minimum(self, other: f16) -> f16 {
-        #[cfg(not(bootstrap))]
-        {
-            intrinsics::minimumf16(self, other)
-        }
-        #[cfg(bootstrap)]
-        {
-            if self < other {
-                self
-            } else if other < self {
-                other
-            } else if self == other {
-                if self.is_sign_negative() && other.is_sign_positive() { self } else { other }
-            } else {
-                // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
-                self + other
-            }
-        }
+        intrinsics::minimumf16(self, other)
     }
 
     /// Calculates the midpoint (average) between `self` and `rhs`.
diff --git a/library/core/src/num/f32.rs b/library/core/src/num/f32.rs
index 9ee6c3f5f99..da241785d64 100644
--- a/library/core/src/num/f32.rs
+++ b/library/core/src/num/f32.rs
@@ -942,25 +942,9 @@ impl f32 {
     /// operand is conserved; see the [specification of NaN bit patterns](f32#nan-bit-patterns) for more info.
     #[must_use = "this returns the result of the comparison, without modifying either input"]
     #[unstable(feature = "float_minimum_maximum", issue = "91079")]
-    #[rustc_const_unstable(feature = "float_minimum_maximum", issue = "91079")]
     #[inline]
     pub const fn maximum(self, other: f32) -> f32 {
-        #[cfg(not(bootstrap))]
-        {
-            intrinsics::maximumf32(self, other)
-        }
-        #[cfg(bootstrap)]
-        {
-            if self > other {
-                self
-            } else if other > self {
-                other
-            } else if self == other {
-                if self.is_sign_positive() && other.is_sign_negative() { self } else { other }
-            } else {
-                self + other
-            }
-        }
+        intrinsics::maximumf32(self, other)
     }
 
     /// Returns the minimum of the two numbers, propagating NaN.
@@ -985,26 +969,9 @@ impl f32 {
     /// operand is conserved; see the [specification of NaN bit patterns](f32#nan-bit-patterns) for more info.
     #[must_use = "this returns the result of the comparison, without modifying either input"]
     #[unstable(feature = "float_minimum_maximum", issue = "91079")]
-    #[rustc_const_unstable(feature = "float_minimum_maximum", issue = "91079")]
     #[inline]
     pub const fn minimum(self, other: f32) -> f32 {
-        #[cfg(not(bootstrap))]
-        {
-            intrinsics::minimumf32(self, other)
-        }
-        #[cfg(bootstrap)]
-        {
-            if self < other {
-                self
-            } else if other < self {
-                other
-            } else if self == other {
-                if self.is_sign_negative() && other.is_sign_positive() { self } else { other }
-            } else {
-                // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
-                self + other
-            }
-        }
+        intrinsics::minimumf32(self, other)
     }
 
     /// Calculates the midpoint (average) between `self` and `rhs`.
diff --git a/library/core/src/num/f64.rs b/library/core/src/num/f64.rs
index 900b936268a..c8544771a90 100644
--- a/library/core/src/num/f64.rs
+++ b/library/core/src/num/f64.rs
@@ -960,25 +960,9 @@ impl f64 {
     /// operand is conserved; see the [specification of NaN bit patterns](f32#nan-bit-patterns) for more info.
     #[must_use = "this returns the result of the comparison, without modifying either input"]
     #[unstable(feature = "float_minimum_maximum", issue = "91079")]
-    #[rustc_const_unstable(feature = "float_minimum_maximum", issue = "91079")]
     #[inline]
     pub const fn maximum(self, other: f64) -> f64 {
-        #[cfg(not(bootstrap))]
-        {
-            intrinsics::maximumf64(self, other)
-        }
-        #[cfg(bootstrap)]
-        {
-            if self > other {
-                self
-            } else if other > self {
-                other
-            } else if self == other {
-                if self.is_sign_positive() && other.is_sign_negative() { self } else { other }
-            } else {
-                self + other
-            }
-        }
+        intrinsics::maximumf64(self, other)
     }
 
     /// Returns the minimum of the two numbers, propagating NaN.
@@ -1003,26 +987,9 @@ impl f64 {
     /// operand is conserved; see the [specification of NaN bit patterns](f32#nan-bit-patterns) for more info.
     #[must_use = "this returns the result of the comparison, without modifying either input"]
     #[unstable(feature = "float_minimum_maximum", issue = "91079")]
-    #[rustc_const_unstable(feature = "float_minimum_maximum", issue = "91079")]
     #[inline]
     pub const fn minimum(self, other: f64) -> f64 {
-        #[cfg(not(bootstrap))]
-        {
-            intrinsics::minimumf64(self, other)
-        }
-        #[cfg(bootstrap)]
-        {
-            if self < other {
-                self
-            } else if other < self {
-                other
-            } else if self == other {
-                if self.is_sign_negative() && other.is_sign_positive() { self } else { other }
-            } else {
-                // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
-                self + other
-            }
-        }
+        intrinsics::minimumf64(self, other)
     }
 
     /// Calculates the midpoint (average) between `self` and `rhs`.