Use LLVM intrinsics for floating-point min/max

Cargo.lock

@@ -25,7 +25,7 @@ dependencies = [
 name = "alloc"
 version = "0.0.0"
 dependencies = [
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_xorshift 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -118,7 +118,7 @@ dependencies = [
  "autocfg 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "backtrace-sys 0.1.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "cfg-if 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.54 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-demangle 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
@@ -130,7 +130,7 @@ version = "0.1.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cc 1.0.35 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.54 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
@@ -357,7 +357,7 @@ name = "cfg-if"
 version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
 
@@ -486,7 +486,7 @@ dependencies = [
 
 [[package]]
 name = "compiler_builtins"
-version = "0.1.15"
+version = "0.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cc 1.0.35 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -768,7 +768,7 @@ name = "dlmalloc"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.54 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
@@ -934,7 +934,7 @@ name = "fortanix-sgx-abi"
 version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
 
@@ -1095,7 +1095,7 @@ name = "hashbrown"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-alloc 1.0.0",
  "rustc-std-workspace-core 1.0.0",
 ]
@@ -1803,7 +1803,7 @@ dependencies = [
 name = "panic_abort"
 version = "0.0.0"
 dependencies = [
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "libc 0.2.54 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1813,7 +1813,7 @@ name = "panic_unwind"
 version = "0.0.0"
 dependencies = [
  "alloc 0.0.0",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "libc 0.2.54 (registry+https://github.com/rust-lang/crates.io-index)",
  "unwind 0.0.0",
@@ -1998,7 +1998,7 @@ name = "profiler_builtins"
 version = "0.0.0"
 dependencies = [
  "cc 1.0.35 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2518,7 +2518,7 @@ name = "rustc-demangle"
 version = "0.1.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
 
@@ -2646,7 +2646,7 @@ dependencies = [
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.38 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2878,7 +2878,7 @@ dependencies = [
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.38 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2941,7 +2941,7 @@ dependencies = [
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.38 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -3060,7 +3060,7 @@ dependencies = [
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.38 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -3338,7 +3338,7 @@ dependencies = [
  "alloc 0.0.0",
  "backtrace 0.3.29 (registry+https://github.com/rust-lang/crates.io-index)",
  "cc 1.0.35 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "dlmalloc 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "fortanix-sgx-abi 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3936,7 +3936,7 @@ name = "unwind"
 version = "0.0.0"
 dependencies = [
  "cc 1.0.35 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "libc 0.2.54 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -4149,7 +4149,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum colored 1.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b0aa3473e85a3161b59845d6096b289bb577874cafeaf75ea1b1beaa6572c7fc"
 "checksum commoncrypto 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d056a8586ba25a1e4d61cb090900e495952c7886786fc55f909ab2f819b69007"
 "checksum commoncrypto-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1fed34f46747aa73dfaa578069fd8279d2818ade2b55f38f22a9401c7f4083e2"
-"checksum compiler_builtins 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)" = "e899b947d7e71c3d35c0b6194d64025b84946640510e215090c815b20828964e"
+"checksum compiler_builtins 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)" = "e79ed19793c99771b386d76e08c3419409bb3d418b81a8b8afc73524247461cf"
 "checksum compiletest_rs 0.3.22 (registry+https://github.com/rust-lang/crates.io-index)" = "f40ecc9332b68270998995c00f8051ee856121764a0d3230e64c9efd059d27b6"
 "checksum constant_time_eq 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "8ff012e225ce166d4422e0e78419d901719760f62ae2b7969ca6b564d1b54a9e"
 "checksum core-foundation 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)" = "4e2640d6d0bf22e82bed1b73c6aef8d5dd31e5abe6666c57e6d45e2649f4f887"

src/libcore/intrinsics.rs

@@ -1051,6 +1051,19 @@ extern "rust-intrinsic" {
     /// Returns the absolute value of an `f64`.
     pub fn fabsf64(x: f64) -> f64;
 
+    /// Returns the minimum of two `f32` values.
+    #[cfg(not(bootstrap))]
+    pub fn minnumf32(x: f32, y: f32) -> f32;
+    /// Returns the minimum of two `f64` values.
+    #[cfg(not(bootstrap))]
+    pub fn minnumf64(x: f64, y: f64) -> f64;
+    /// Returns the maximum of two `f32` values.
+    #[cfg(not(bootstrap))]
+    pub fn maxnumf32(x: f32, y: f32) -> f32;
+    /// Returns the maximum of two `f64` values.
+    #[cfg(not(bootstrap))]
+    pub fn maxnumf64(x: f64, y: f64) -> f64;
+
     /// Copies the sign from `y` to `x` for `f32` values.
     pub fn copysignf32(x: f32, y: f32) -> f32;
     /// Copies the sign from `y` to `x` for `f64` values.
@@ -1561,3 +1574,47 @@ pub unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
 pub unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize) {
     real_intrinsics::write_bytes(dst, val, count)
 }
+
+// Simple bootstrap implementations of minnum/maxnum for stage0 compilation.
+
+/// Returns the minimum of two `f32` values.
+#[cfg(bootstrap)]
+pub fn minnumf32(x: f32, y: f32) -> f32 {
+    // IEEE754 says: minNum(x, y) is the canonicalized number x if x < y, y if y < x, the
+    // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
+    // is either x or y, canonicalized (this means results might differ among implementations).
+    // When either x or y is a signaling NaN, then the result is according to 6.2.
+    //
+    // Since we do not support sNaN in Rust yet, we do not need to handle them.
+    // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
+    // multiplying by 1.0. Should switch to the `canonicalize` when it works.
+    (if x < y || y != y { x } else { y }) * 1.0
+}
+
+/// Returns the minimum of two `f64` values.
+#[cfg(bootstrap)]
+pub fn minnumf64(x: f64, y: f64) -> f64 {
+    // Identical to the `f32` case.
+    (if x < y || y != y { x } else { y }) * 1.0
+}
+
+/// Returns the maximum of two `f32` values.
+#[cfg(bootstrap)]
+pub fn maxnumf32(x: f32, y: f32) -> f32 {
+    // IEEE754 says: maxNum(x, y) is the canonicalized number y if x < y, x if y < x, the
+    // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
+    // is either x or y, canonicalized (this means results might differ among implementations).
+    // When either x or y is a signaling NaN, then the result is according to 6.2.
+    //
+    // Since we do not support sNaN in Rust yet, we do not need to handle them.
+    // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
+    // multiplying by 1.0. Should switch to the `canonicalize` when it works.
+    (if x < y || x != x { y } else { x }) * 1.0
+}
+
+/// Returns the maximum of two `f64` values.
+#[cfg(bootstrap)]
+pub fn maxnumf64(x: f64, y: f64) -> f64 {
+    // Identical to the `f32` case.
+    (if x < y || x != x { y } else { x }) * 1.0
+}

src/libcore/num/f32.rs

@@ -7,6 +7,9 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 
+#[cfg(not(test))]
+use crate::intrinsics;
+
 use crate::mem;
 use crate::num::FpCategory;
 
@@ -372,15 +375,7 @@ impl f32 {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn max(self, other: f32) -> f32 {
-        // IEEE754 says: maxNum(x, y) is the canonicalized number y if x < y, x if y < x, the
-        // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
-        // is either x or y, canonicalized (this means results might differ among implementations).
-        // When either x or y is a signalingNaN, then the result is according to 6.2.
-        //
-        // Since we do not support sNaN in Rust yet, we do not need to handle them.
-        // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
-        // multiplying by 1.0. Should switch to the `canonicalize` when it works.
-        (if self.is_nan() || self < other { other } else { self }) * 1.0
+        intrinsics::maxnumf32(self, other)
     }
 
     /// Returns the minimum of the two numbers.
@@ -396,15 +391,7 @@ impl f32 {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn min(self, other: f32) -> f32 {
-        // IEEE754 says: minNum(x, y) is the canonicalized number x if x < y, y if y < x, the
-        // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
-        // is either x or y, canonicalized (this means results might differ among implementations).
-        // When either x or y is a signalingNaN, then the result is according to 6.2.
-        //
-        // Since we do not support sNaN in Rust yet, we do not need to handle them.
-        // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
-        // multiplying by 1.0. Should switch to the `canonicalize` when it works.
-        (if other.is_nan() || self < other { self } else { other }) * 1.0
+        intrinsics::minnumf32(self, other)
     }
 
     /// Raw transmutation to `u32`.

src/libcore/num/f64.rs

@@ -7,6 +7,9 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 
+#[cfg(not(test))]
+use crate::intrinsics;
+
 use crate::mem;
 use crate::num::FpCategory;
 
@@ -385,15 +388,7 @@ impl f64 {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn max(self, other: f64) -> f64 {
-        // IEEE754 says: maxNum(x, y) is the canonicalized number y if x < y, x if y < x, the
-        // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
-        // is either x or y, canonicalized (this means results might differ among implementations).
-        // When either x or y is a signalingNaN, then the result is according to 6.2.
-        //
-        // Since we do not support sNaN in Rust yet, we do not need to handle them.
-        // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
-        // multiplying by 1.0. Should switch to the `canonicalize` when it works.
-        (if self.is_nan() || self < other { other } else { self }) * 1.0
+        intrinsics::maxnumf64(self, other)
     }
 
     /// Returns the minimum of the two numbers.
@@ -409,15 +404,7 @@ impl f64 {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn min(self, other: f64) -> f64 {
-        // IEEE754 says: minNum(x, y) is the canonicalized number x if x < y, y if y < x, the
-        // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
-        // is either x or y, canonicalized (this means results might differ among implementations).
-        // When either x or y is a signalingNaN, then the result is according to 6.2.
-        //
-        // Since we do not support sNaN in Rust yet, we do not need to handle them.
-        // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
-        // multiplying by 1.0. Should switch to the `canonicalize` when it works.
-        (if other.is_nan() || self < other { self } else { other }) * 1.0
+        intrinsics::minnumf64(self, other)
     }
 
     /// Raw transmutation to `u64`.

src/librustc_codegen_llvm/context.rs

@@ -645,6 +645,11 @@ impl CodegenCx<'b, 'tcx> {
         ifn!("llvm.fabs.v4f64", fn(t_v4f64) -> t_v4f64);
         ifn!("llvm.fabs.v8f64", fn(t_v8f64) -> t_v8f64);
 
+        ifn!("llvm.minnum.f32", fn(t_f32, t_f32) -> t_f32);
+        ifn!("llvm.minnum.f64", fn(t_f64, t_f64) -> t_f64);
+        ifn!("llvm.maxnum.f32", fn(t_f32, t_f32) -> t_f32);
+        ifn!("llvm.maxnum.f64", fn(t_f64, t_f64) -> t_f64);
+
         ifn!("llvm.floor.f32", fn(t_f32) -> t_f32);
         ifn!("llvm.floor.v2f32", fn(t_v2f32) -> t_v2f32);
         ifn!("llvm.floor.v4f32", fn(t_v4f32) -> t_v4f32);

src/librustc_codegen_llvm/intrinsic.rs

@@ -55,6 +55,10 @@ fn get_simple_intrinsic(cx: &CodegenCx<'ll, '_>, name: &str) -> Option<&'ll Valu
         "fmaf64" => "llvm.fma.f64",
         "fabsf32" => "llvm.fabs.f32",
         "fabsf64" => "llvm.fabs.f64",
+        "minnumf32" => "llvm.minnum.f32",
+        "minnumf64" => "llvm.minnum.f64",
+        "maxnumf32" => "llvm.maxnum.f32",
+        "maxnumf64" => "llvm.maxnum.f64",
         "copysignf32" => "llvm.copysign.f32",
         "copysignf64" => "llvm.copysign.f64",
         "floorf32" => "llvm.floor.f32",

src/librustc_typeck/check/intrinsic.rs

@@ -70,7 +70,8 @@ pub fn intrisic_operation_unsafety(intrinsic: &str) -> hir::Unsafety {
         "overflowing_add" | "overflowing_sub" | "overflowing_mul" |
         "saturating_add" | "saturating_sub" |
         "rotate_left" | "rotate_right" |
-        "ctpop" | "ctlz" | "cttz" | "bswap" | "bitreverse"
+        "ctpop" | "ctlz" | "cttz" | "bswap" | "bitreverse" |
+        "minnumf32" | "minnumf64" | "maxnumf32" | "maxnumf64"
         => hir::Unsafety::Normal,
         _ => hir::Unsafety::Unsafe,
     }
@@ -272,6 +273,10 @@ pub fn check_intrinsic_type<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
             }
             "fabsf32"      => (0, vec![ tcx.types.f32 ], tcx.types.f32),
             "fabsf64"      => (0, vec![ tcx.types.f64 ], tcx.types.f64),
+            "minnumf32"    => (0, vec![ tcx.types.f32, tcx.types.f32 ], tcx.types.f32),
+            "minnumf64"    => (0, vec![ tcx.types.f64, tcx.types.f64 ], tcx.types.f64),
+            "maxnumf32"    => (0, vec![ tcx.types.f32, tcx.types.f32 ], tcx.types.f32),
+            "maxnumf64"    => (0, vec![ tcx.types.f64, tcx.types.f64 ], tcx.types.f64),
             "copysignf32"  => (0, vec![ tcx.types.f32, tcx.types.f32 ], tcx.types.f32),
             "copysignf64"  => (0, vec![ tcx.types.f64, tcx.types.f64 ], tcx.types.f64),
             "floorf32"     => (0, vec![ tcx.types.f32 ], tcx.types.f32),

src/libstd/Cargo.toml

@@ -19,7 +19,7 @@ panic_unwind = { path = "../libpanic_unwind", optional = true }
 panic_abort = { path = "../libpanic_abort" }
 core = { path = "../libcore" }
 libc = { version = "0.2.51", default-features = false, features = ['rustc-dep-of-std'] }
-compiler_builtins = { version = "0.1.15" }
+compiler_builtins = { version = "0.1.16" }
 profiler_builtins = { path = "../libprofiler_builtins", optional = true }
 unwind = { path = "../libunwind" }
 hashbrown = { version = "0.4.0", features = ['rustc-dep-of-std'] }