rp: hook up softfloat rom intrinsics

rp-hal has done this very well already, so we'll just copy their entire
impl again. only div.rs needed some massaging because our sio access
works a little differently, everything else worked as is.

embassy-rp/src/float/cmp.rs

@@ -0,0 +1,201 @@
+// Credit: taken from `rp-hal` (also licensed Apache+MIT)
+// https://github.com/rp-rs/rp-hal/blob/main/rp2040-hal/src/float/cmp.rs
+
+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
+    }
+}