diff --git a/src/unwinder/arch/mod.rs b/src/unwinder/arch/mod.rs index 4bd2cbd..dcd60f5 100644 --- a/src/unwinder/arch/mod.rs +++ b/src/unwinder/arch/mod.rs @@ -2,3 +2,8 @@ mod x86_64; #[cfg(target_arch = "x86_64")] pub use x86_64::*; + +#[cfg(target_arch = "riscv64")] +mod riscv64; +#[cfg(target_arch = "riscv64")] +pub use riscv64::*; diff --git a/src/unwinder/arch/riscv64.rs b/src/unwinder/arch/riscv64.rs new file mode 100644 index 0000000..716f432 --- /dev/null +++ b/src/unwinder/arch/riscv64.rs @@ -0,0 +1,195 @@ +use core::fmt; +use core::ops; +use gimli::{Register, RiscV}; + +#[repr(C)] +#[derive(Clone, Default)] +pub struct Context { + pub gp: [usize; 32], + pub fp: [usize; 32], +} + +impl fmt::Debug for Context { + fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { + let mut fmt = fmt.debug_struct("Context"); + for i in 0..=31 { + fmt.field(RiscV::register_name(Register(i as _)).unwrap(), &self.gp[i]); + } + for i in 0..=31 { + fmt.field( + RiscV::register_name(Register((i + 32) as _)).unwrap(), + &self.fp[i], + ); + } + fmt.finish() + } +} + +impl ops::Index for Context { + type Output = usize; + + fn index(&self, reg: Register) -> &usize { + match reg { + Register(0..=31) => &self.gp[reg.0 as usize], + Register(32..=63) => &self.fp[(reg.0 - 32) as usize], + _ => unimplemented!(), + } + } +} + +impl ops::IndexMut for Context { + fn index_mut(&mut self, reg: Register) -> &mut usize { + match reg { + Register(0..=31) => &mut self.gp[reg.0 as usize], + Register(32..=63) => &mut self.fp[(reg.0 - 32) as usize], + _ => unimplemented!(), + } + } +} + +macro_rules! code { + (save_gp) => { + " + sd x0, 0x00(a0) + sd ra, 0x08(a0) + sd sp, 0x10(a0) + sd gp, 0x18(a0) + sd tp, 0x20(a0) + sd s0, 0x40(a0) + sd s1, 0x48(a0) + sd s2, 0x90(a0) + sd s3, 0x98(a0) + sd s4, 0xA0(a0) + sd s5, 0xA8(a0) + sd s6, 0xB0(a0) + sd s7, 0xB8(a0) + sd s8, 0xC0(a0) + sd s9, 0xC8(a0) + sd s10, 0xD0(a0) + sd s11, 0xD8(a0) + " + }; + (save_fp) => { + " + fsd fs0, 0x140(a0) + fsd fs1, 0x148(a0) + fsd fs2, 0x190(a0) + fsd fs3, 0x198(a0) + fsd fs4, 0x1A0(a0) + fsd fs5, 0x1A8(a0) + fsd fs6, 0x1B0(a0) + fsd fs7, 0x1B8(a0) + fsd fs8, 0x1C0(a0) + fsd fs9, 0x1C8(a0) + fsd fs10, 0x1D0(a0) + fsd fs11, 0x1D8(a0) + " + }; + (restore_gp) => { + " + ld ra, 0x08(a0) + ld sp, 0x10(a0) + ld gp, 0x18(a0) + ld tp, 0x20(a0) + ld t0, 0x28(a0) + ld t1, 0x30(a0) + ld t2, 0x38(a0) + ld s0, 0x40(a0) + ld s1, 0x48(a0) + ld a1, 0x58(a0) + ld a2, 0x60(a0) + ld a3, 0x68(a0) + ld a4, 0x70(a0) + ld a5, 0x78(a0) + ld a6, 0x80(a0) + ld a7, 0x88(a0) + ld s2, 0x90(a0) + ld s3, 0x98(a0) + ld s4, 0xA0(a0) + ld s5, 0xA8(a0) + ld s6, 0xB0(a0) + ld s7, 0xB8(a0) + ld s8, 0xC0(a0) + ld s9, 0xC8(a0) + ld s10, 0xD0(a0) + ld s11, 0xD8(a0) + ld t3, 0xE0(a0) + ld t4, 0xE8(a0) + ld t5, 0xF0(a0) + ld t6, 0xF8(a0) + " + }; + (restore_fp) => { + " + fld ft0, 0x100(a0) + fld ft1, 0x108(a0) + fld ft2, 0x110(a0) + fld ft3, 0x118(a0) + fld ft4, 0x120(a0) + fld ft5, 0x128(a0) + fld ft6, 0x130(a0) + fld ft7, 0x138(a0) + fld fs0, 0x140(a0) + fld fs1, 0x148(a0) + fld fa0, 0x150(a0) + fld fa1, 0x158(a0) + fld fa2, 0x160(a0) + fld fa3, 0x168(a0) + fld fa4, 0x170(a0) + fld fa5, 0x178(a0) + fld fa6, 0x180(a0) + fld fa7, 0x188(a0) + fld fs2, 0x190(a0) + fld fs3, 0x198(a0) + fld fs4, 0x1A0(a0) + fld fs5, 0x1A8(a0) + fld fs6, 0x1B0(a0) + fld fs7, 0x1B8(a0) + fld fs8, 0x1C0(a0) + fld fs9, 0x1C8(a0) + fld fs10, 0x1D0(a0) + fld fs11, 0x1D8(a0) + fld ft8, 0x1E0(a0) + fld ft9, 0x1E8(a0) + fld ft10, 0x1F0(a0) + fld ft11, 0x1F8(a0) + " + }; +} + +#[naked] +pub extern "C-unwind" fn save_context() -> Context { + // No need to save caller-saved registers here. + #[cfg(target_feature = "d")] + unsafe { + asm!( + concat!(code!(save_gp), code!(save_fp), "ret"), + options(noreturn) + ); + } + #[cfg(not(target_feature = "d"))] + unsafe { + asm!( + concat!(code!(save_gp), "ret"), + options(noreturn) + ); + } +} + +#[naked] +pub unsafe extern "C" fn restore_context(ctx: &Context) -> ! { + #[cfg(target_feature = "d")] + unsafe { + asm!( + concat!(code!(restore_fp), code!(restore_gp), "ld a0, 0x50(a0)\nret"), + options(noreturn) + ); + } + #[cfg(not(target_feature = "d"))] + unsafe { + asm!( + concat!(code!(restore_gp), "ld a0, 0x50(a0)\nret"), + options(noreturn) + ); + } +}