Add ROM floating point math library

Hook up the ROM functions to floating point intrinsics.

rp2040-hal/src/float/add_sub.rs

@@ -0,0 +1,89 @@
+use super::{Float, Int};
+use crate::rom_data;
+
+trait ROMAdd {
+    fn rom_add(self, b: Self) -> Self;
+}
+
+impl ROMAdd for f32 {
+    fn rom_add(self, b: Self) -> Self {
+        rom_data::float_funcs::fadd(self, b)
+    }
+}
+
+impl ROMAdd for f64 {
+    fn rom_add(self, b: Self) -> Self {
+        rom_data::double_funcs::dadd(self, b)
+    }
+}
+
+fn add<F: Float + ROMAdd>(a: F, b: F) -> F {
+    if a.is_not_finite() {
+        if b.is_not_finite() {
+            let class_a = a.repr() & (F::SIGNIFICAND_MASK | F::SIGN_MASK);
+            let class_b = b.repr() & (F::SIGNIFICAND_MASK | F::SIGN_MASK);
+
+            if class_a == F::Int::ZERO && class_b == F::Int::ZERO {
+                // inf + inf = inf
+                return a;
+            }
+            if class_a == F::SIGN_MASK && class_b == F::SIGN_MASK {
+                // -inf + (-inf) = -inf
+                return a;
+            }
+
+            // Sign mismatch, or either is NaN already
+            return F::NAN;
+        }
+
+        // [-]inf/NaN + X = [-]inf/NaN
+        return a;
+    }
+
+    if b.is_not_finite() {
+        // X + [-]inf/NaN = [-]inf/NaN
+        return b;
+    }
+
+    a.rom_add(b)
+}
+
+intrinsics! {
+    #[alias = __addsf3vfp]
+    #[aeabi = __aeabi_fadd]
+    extern "C" fn __addsf3(a: f32, b: f32) -> f32 {
+        add(a, b)
+    }
+
+    #[bootrom_v2]
+    #[alias = __adddf3vfp]
+    #[aeabi = __aeabi_dadd]
+    extern "C" fn __adddf3(a: f64, b: f64) -> f64 {
+        add(a, b)
+    }
+
+    // The ROM just implements subtraction the same way, so just do it here
+    // and save the work of implementing more complicated NaN/inf handling.
+
+    #[alias = __subsf3vfp]
+    #[aeabi = __aeabi_fsub]
+    extern "C" fn __subsf3(a: f32, b: f32) -> f32 {
+        add(a, -b)
+    }
+
+    #[bootrom_v2]
+    #[alias = __subdf3vfp]
+    #[aeabi = __aeabi_dsub]
+    extern "C" fn __subdf3(a: f64, b: f64) -> f64 {
+        add(a, -b)
+    }
+
+    extern "aapcs" fn __aeabi_frsub(a: f32, b: f32) -> f32 {
+        add(b, -a)
+    }
+
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_drsub(a: f64, b: f64) -> f64 {
+        add(b, -a)
+    }
+}

rp2040-hal/src/float/cmp.rs

@@ -0,0 +1,198 @@
+use super::Float;
+use crate::rom_data;
+
+trait ROMCmp {
+    fn rom_cmp(self, b: Self) -> i32;
+}
+
+impl ROMCmp for f32 {
+    fn rom_cmp(self, b: Self) -> i32 {
+        rom_data::float_funcs::fcmp(self, b)
+    }
+}
+
+impl ROMCmp for f64 {
+    fn rom_cmp(self, b: Self) -> i32 {
+        rom_data::double_funcs::dcmp(self, b)
+    }
+}
+
+fn le_abi<F: Float + ROMCmp>(a: F, b: F) -> i32 {
+    if a.is_nan() || b.is_nan() {
+        1
+    } else {
+        a.rom_cmp(b)
+    }
+}
+
+fn ge_abi<F: Float + ROMCmp>(a: F, b: F) -> i32 {
+    if a.is_nan() || b.is_nan() {
+        -1
+    } else {
+        a.rom_cmp(b)
+    }
+}
+
+intrinsics! {
+    #[slower_than_default]
+    #[bootrom_v2]
+    #[alias = __eqsf2, __ltsf2, __nesf2]
+    extern "C" fn __lesf2(a: f32, b: f32) -> i32 {
+        le_abi(a, b)
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    #[alias = __eqdf2, __ltdf2, __nedf2]
+    extern "C" fn __ledf2(a: f64, b: f64) -> i32 {
+        le_abi(a, b)
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    #[alias = __gtsf2]
+    extern "C" fn __gesf2(a: f32, b: f32) -> i32 {
+        ge_abi(a, b)
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    #[alias = __gtdf2]
+    extern "C" fn __gedf2(a: f64, b: f64) -> i32 {
+        ge_abi(a, b)
+    }
+
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_fcmple(a: f32, b: f32) -> i32 {
+        (le_abi(a, b) <= 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_fcmpge(a: f32, b: f32) -> i32 {
+        (ge_abi(a, b) >= 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_fcmpeq(a: f32, b: f32) -> i32 {
+        (le_abi(a, b) == 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_fcmplt(a: f32, b: f32) -> i32 {
+        (le_abi(a, b) < 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_fcmpgt(a: f32, b: f32) -> i32 {
+        (ge_abi(a, b) > 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_dcmple(a: f64, b: f64) -> i32 {
+        (le_abi(a, b) <= 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_dcmpge(a: f64, b: f64) -> i32 {
+        (ge_abi(a, b) >= 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_dcmpeq(a: f64, b: f64) -> i32 {
+        (le_abi(a, b) == 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_dcmplt(a: f64, b: f64) -> i32 {
+        (le_abi(a, b) < 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "aapcs" fn __aeabi_dcmpgt(a: f64, b: f64) -> i32 {
+        (ge_abi(a, b) > 0) as i32
+    }
+
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __gesf2vfp(a: f32, b: f32) -> i32 {
+        (ge_abi(a, b) >= 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __gedf2vfp(a: f64, b: f64) -> i32 {
+        (ge_abi(a, b) >= 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __gtsf2vfp(a: f32, b: f32) -> i32 {
+        (ge_abi(a, b) > 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __gtdf2vfp(a: f64, b: f64) -> i32 {
+        (ge_abi(a, b) > 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __ltsf2vfp(a: f32, b: f32) -> i32 {
+        (le_abi(a, b) < 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __ltdf2vfp(a: f64, b: f64) -> i32 {
+        (le_abi(a, b) < 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __lesf2vfp(a: f32, b: f32) -> i32 {
+        (le_abi(a, b) <= 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __ledf2vfp(a: f64, b: f64) -> i32 {
+        (le_abi(a, b) <= 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __nesf2vfp(a: f32, b: f32) -> i32 {
+        (le_abi(a, b) != 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __nedf2vfp(a: f64, b: f64) -> i32 {
+        (le_abi(a, b) != 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __eqsf2vfp(a: f32, b: f32) -> i32 {
+        (le_abi(a, b) == 0) as i32
+    }
+
+    #[slower_than_default]
+    #[bootrom_v2]
+    extern "C" fn __eqdf2vfp(a: f64, b: f64) -> i32 {
+        (le_abi(a, b) == 0) as i32
+    }
+}