Add fmaf16 and fmaf128

crates/compiler-builtins-smoke-test/src/lib.rs

@@ -7,6 +7,7 @@
 #![no_std]
 
 #[allow(dead_code)]
+#[allow(unused_imports)]
 #[allow(clippy::all)] // We don't get `libm`'s list of `allow`s, so just ignore Clippy.
 #[path = "../../../src/math/mod.rs"]
 pub mod libm;

crates/libm-macros/src/shared.rs

@@ -92,6 +92,13 @@ const ALL_OPERATIONS_NESTED: &[(FloatTy, Signature, Option<Signature>, &[&str])]
         None,
         &["copysignf128"],
     ),
+    (
+        // `(f16, f16, f16) -> f16`
+        FloatTy::F16,
+        Signature { args: &[Ty::F16, Ty::F16, Ty::F16], returns: &[Ty::F16] },
+        None,
+        &["fmaf16"],
+    ),
     (
         // `(f32, f32, f32) -> f32`
         FloatTy::F32,
@@ -106,6 +113,13 @@ const ALL_OPERATIONS_NESTED: &[(FloatTy, Signature, Option<Signature>, &[&str])]
         None,
         &["fma"],
     ),
+    (
+        // `(f128, f128, f128) -> f128`
+        FloatTy::F128,
+        Signature { args: &[Ty::F128, Ty::F128, Ty::F128], returns: &[Ty::F128] },
+        None,
+        &["fmaf128"],
+    ),
     (
         // `(f32) -> i32`
         FloatTy::F32,

crates/libm-test/benches/random.rs

@@ -117,7 +117,8 @@ libm_macros::for_each_function! {
         exp10 | exp10f | exp2 | exp2f => (true, Some(musl_math_sys::MACRO_FN_NAME)),
 
         // Musl does not provide `f16` and `f128` functions
-        copysignf16 | copysignf128 | fabsf16 | fabsf128 => (false, None),
+        copysignf16 | copysignf128 | fabsf16 | fabsf128 |
+            fmaf16 | fmaf128  => (false, None),
 
         // By default we never skip (false) and always have a musl function available
         _ => (false, Some(musl_math_sys::MACRO_FN_NAME))

crates/libm-test/src/f8_impl.rs

@@ -20,7 +20,6 @@ pub struct f8(u8);
 impl Float for f8 {
     type Int = u8;
     type SignedInt = i8;
-    type ExpInt = i8;
 
     const ZERO: Self = Self(0b0_0000_000);
     const NEG_ZERO: Self = Self(0b1_0000_000);
@@ -62,8 +61,8 @@ impl Float for f8 {
         self.0 & Self::SIGN_MASK != 0
     }
 
-    fn exp(self) -> Self::ExpInt {
-        unimplemented!()
+    fn exp(self) -> i32 {
+        ((self.to_bits() & Self::EXP_MASK) >> Self::SIG_BITS) as i32
     }
 
     fn from_bits(a: Self::Int) -> Self {

crates/libm-test/src/mpfloat.rs

@@ -144,7 +144,7 @@ libm_macros::for_each_function! {
         expm1 | expm1f => exp_m1,
         fabs | fabsf => abs,
         fdim | fdimf => positive_diff,
-        fma | fmaf => mul_add,
+        fma | fmaf | fmaf16 | fmaf128 => mul_add,
         fmax | fmaxf => max,
         fmin | fminf => min,
         lgamma | lgammaf => ln_gamma,

crates/libm-test/src/precision.rs

@@ -459,7 +459,12 @@ fn bessel_prec_dropoff<F: Float>(
     None
 }
 
+#[cfg(f16_enabled)]
+impl MaybeOverride<(f16, f16, f16)> for SpecialCase {}
 impl MaybeOverride<(f32, f32, f32)> for SpecialCase {}
 impl MaybeOverride<(f64, f64, f64)> for SpecialCase {}
+#[cfg(f128_enabled)]
+impl MaybeOverride<(f128, f128, f128)> for SpecialCase {}
+
 impl MaybeOverride<(f32, i32)> for SpecialCase {}
 impl MaybeOverride<(f64, i32)> for SpecialCase {}

crates/libm-test/tests/compare_built_musl.rs

@@ -47,7 +47,7 @@ where
 libm_macros::for_each_function! {
     callback: musl_rand_tests,
     // Musl does not support `f16` and `f128` on all platforms.
-    skip: [copysignf16, copysignf128, fabsf16, fabsf128],
+    skip: [copysignf16, copysignf128, fabsf16, fabsf128, fmaf16, fmaf128],
     attributes: [
         #[cfg_attr(x86_no_sse, ignore)] // FIXME(correctness): wrong result on i586
         [exp10, exp10f, exp2, exp2f, rint]

crates/libm-test/tests/multiprecision.rs

@@ -126,6 +126,8 @@ libm_macros::for_each_function! {
         fdimf,
         fma,
         fmaf,
+        fmaf16,
+        fmaf128,
         fmax,
         fmaxf,
         fmin,

etc/function-definitions.json

@@ -318,16 +318,32 @@
     "fma": {
         "sources": [
             "src/libm_helper.rs",
-            "src/math/fma.rs"
+            "src/math/fma.rs",
+            "src/math/generic/fma.rs"
         ],
         "type": "f64"
     },
     "fmaf": {
         "sources": [
-            "src/math/fmaf.rs"
+            "src/math/fmaf.rs",
+            "src/math/generic/fma.rs"
         ],
         "type": "f32"
     },
+    "fmaf128": {
+        "sources": [
+            "src/math/fmaf128.rs",
+            "src/math/generic/fma.rs"
+        ],
+        "type": "f128"
+    },
+    "fmaf16": {
+        "sources": [
+            "src/math/fmaf16.rs",
+            "src/math/generic/fma.rs"
+        ],
+        "type": "f16"
+    },
     "fmax": {
         "sources": [
             "src/libm_helper.rs",

etc/function-list.txt

@@ -47,6 +47,8 @@ floor
 floorf
 fma
 fmaf
+fmaf128
+fmaf16
 fmax
 fmaxf
 fmin

src/math/fma.rs

@@ -42,6 +42,10 @@ fn mul(x: u64, y: u64) -> (u64, u64) {
 /// according to the rounding mode characterized by the value of FLT_ROUNDS.
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn fma(x: f64, y: f64, z: f64) -> f64 {
+    if true {
+        return super::generic::fma(x, y, z, scalbn);
+    }
+
     let x1p63: f64 = f64::from_bits(0x43e0000000000000); // 0x1p63 === 2 ^ 63
     let x0_ffffff8p_63 = f64::from_bits(0x3bfffffff0000000); // 0x0.ffffff8p-63
 

src/math/fmaf.rs

@@ -47,6 +47,10 @@ use super::fenv::{
 /// according to the rounding mode characterized by the value of FLT_ROUNDS.
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn fmaf(x: f32, y: f32, mut z: f32) -> f32 {
+    if true {
+        return super::generic::fma_big::<f32, f64>(x, y, z);
+    }
+
     let xy: f64;
     let mut result: f64;
     let mut ui: u64;

src/math/fmaf128.rs

@@ -0,0 +1,6 @@
+#[expect(unused)]
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fmaf128(x: f128, y: f128, z: f128) -> f128 {
+    // super::generic::fma(x, y, z)
+    todo!()
+}

src/math/fmaf16.rs

@@ -0,0 +1,4 @@
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn fmaf16(x: f16, y: f16, z: f16) -> f16 {
+    super::generic::fma_big::<f16, f32>(x, y, z)
+}