From 1dbe047df1b60ebe455fd844a05d1b96a5bbc1fc Mon Sep 17 00:00:00 2001 From: SK83RJOSH Date: Tue, 9 Jan 2024 09:22:06 +0100 Subject: [PATCH] feat(mips): initial support for mips --- src/arch.rs | 21 ++- src/lib.rs | 1 + src/unwinder/arch/mips.rs | 289 ++++++++++++++++++++++++++++++++++++++ src/unwinder/arch/mod.rs | 8 +- 4 files changed, 317 insertions(+), 2 deletions(-) create mode 100644 src/unwinder/arch/mips.rs diff --git a/src/arch.rs b/src/arch.rs index 33b3811..140d079 100644 --- a/src/arch.rs +++ b/src/arch.rs @@ -70,11 +70,30 @@ mod aarch64 { #[cfg(target_arch = "aarch64")] pub use aarch64::*; +#[cfg(target_arch = "mips")] +mod mips { + use gimli::{Register, MIPS}; + + pub struct Arch; + + #[allow(unused)] + impl Arch { + pub const SP: Register = MIPS::SP; + pub const RA: Register = MIPS::RA; + + pub const UNWIND_DATA_REG: (Register, Register) = (MIPS::A0, MIPS::A1); + pub const UNWIND_PRIVATE_DATA_SIZE: usize = 2; + } +} +#[cfg(target_arch = "mips")] +pub use mips::*; + #[cfg(not(any( target_arch = "x86_64", target_arch = "x86", target_arch = "riscv64", target_arch = "riscv32", - target_arch = "aarch64" + target_arch = "aarch64", + target_arch = "mips", )))] compile_error!("Current architecture is not supported"); diff --git a/src/lib.rs b/src/lib.rs index 23e776e..e6de373 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -2,6 +2,7 @@ #![feature(c_unwind)] #![feature(naked_functions)] #![feature(non_exhaustive_omitted_patterns_lint)] +#![cfg_attr(target_arch = "mips", feature(asm_experimental_arch))] // lang_items is an internal feature. `internal_features` lint is added recently // so also allow unknown lints to prevent warning in older nightly versions. #![cfg_attr( diff --git a/src/unwinder/arch/mips.rs b/src/unwinder/arch/mips.rs new file mode 100644 index 0000000..f369641 --- /dev/null +++ b/src/unwinder/arch/mips.rs @@ -0,0 +1,289 @@ +use core::arch::asm; +use core::fmt; +use core::ops; +use gimli::{Register, MIPS}; + +// Match DWARF_FRAME_REGISTERS in libgcc +pub const MAX_REG_RULES: usize = 188; + +#[repr(C)] +#[derive(Clone, Default)] +pub struct Context { + pub gp: [usize; 32], + #[cfg(target_feature = "single-float")] + 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(MIPS::register_name(Register(i as _)).unwrap(), &self.gp[i]); + } + #[cfg(target_feature = "single-float")] + for i in 0..=31 { + fmt.field( + MIPS::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], + #[cfg(target_feature = "single-float")] + 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], + #[cfg(target_feature = "single-float")] + Register(32..=63) => &mut self.fp[(reg.0 - 32) as usize], + _ => unimplemented!(), + } + } +} + +macro_rules! code { + (save_gp) => { + " + sw $zero, 0x00($sp) + sw $s0, 0x40($sp) + sw $s1, 0x44($sp) + sw $s2, 0x48($sp) + sw $s3, 0x4C($sp) + sw $s4, 0x50($sp) + sw $s5, 0x54($sp) + sw $s6, 0x58($sp) + sw $s7, 0x5C($sp) + sw $k0, 0x68($sp) + sw $k1, 0x6C($sp) + sw $gp, 0x70($sp) + sw $t0, 0x74($sp) + sw $fp, 0x78($sp) + sw $ra, 0x7C($sp) + " + }; + (save_fp) => { + " + swc1 $f0, 0x80($sp) + swc1 $f1, 0x84($sp) + swc1 $f2, 0x88($sp) + swc1 $f3, 0x8C($sp) + swc1 $f4, 0x90($sp) + swc1 $f5, 0x94($sp) + swc1 $f6, 0x98($sp) + swc1 $f7, 0x9C($sp) + swc1 $f8, 0xA0($sp) + swc1 $f9, 0xA4($sp) + swc1 $f10, 0xA8($sp) + swc1 $f11, 0xAC($sp) + swc1 $f12, 0xB0($sp) + swc1 $f13, 0xB4($sp) + swc1 $f14, 0xB8($sp) + swc1 $f15, 0xBC($sp) + swc1 $f16, 0xC0($sp) + swc1 $f17, 0xC4($sp) + swc1 $f18, 0xC8($sp) + swc1 $f19, 0xCC($sp) + swc1 $f20, 0xD0($sp) + swc1 $f21, 0xD4($sp) + swc1 $f22, 0xD8($sp) + swc1 $f23, 0xDC($sp) + swc1 $f24, 0xE0($sp) + swc1 $f25, 0xE4($sp) + swc1 $f26, 0xE8($sp) + swc1 $f27, 0xEC($sp) + swc1 $f28, 0xF0($sp) + swc1 $f29, 0xF4($sp) + swc1 $f30, 0xF8($sp) + swc1 $f31, 0xFC($sp) + " + }; + (restore_gp) => { + " + lw $at, 0x04($a0) + lw $v0, 0x08($a0) + lw $v1, 0x0C($a0) + lw $a1, 0x14($a0) + lw $a2, 0x18($a0) + lw $a3, 0x1C($a0) + lw $t0, 0x20($a0) + lw $t1, 0x24($a0) + lw $t2, 0x28($a0) + lw $t3, 0x2C($a0) + lw $t4, 0x30($a0) + lw $t5, 0x34($a0) + lw $t6, 0x38($a0) + lw $t7, 0x3C($a0) + lw $s0, 0x40($a0) + lw $s1, 0x44($a0) + lw $s2, 0x48($a0) + lw $s3, 0x4C($a0) + lw $s4, 0x50($a0) + lw $s5, 0x54($a0) + lw $s6, 0x58($a0) + lw $s7, 0x5C($a0) + lw $t8, 0x60($a0) + lw $t9, 0x64($a0) + lw $k0, 0x68($a0) + lw $k1, 0x6C($a0) + lw $gp, 0x70($a0) + lw $sp, 0x74($a0) + lw $fp, 0x78($a0) + lw $ra, 0x7C($a0) + " + }; + (restore_fp) => { + " + lwc1 $f0, 0x80($a0) + lwc1 $f1, 0x84($a0) + lwc1 $f2, 0x88($a0) + lwc1 $f3, 0x8C($a0) + lwc1 $f4, 0x90($a0) + lwc1 $f5, 0x94($a0) + lwc1 $f6, 0x98($a0) + lwc1 $f7, 0x9C($a0) + lwc1 $f8, 0xA0($a0) + lwc1 $f9, 0xA4($a0) + lwc1 $f10, 0xA8($a0) + lwc1 $f11, 0xAC($a0) + lwc1 $f12, 0xB0($a0) + lwc1 $f13, 0xB4($a0) + lwc1 $f14, 0xB8($a0) + lwc1 $f15, 0xBC($a0) + lwc1 $f16, 0xC0($a0) + lwc1 $f17, 0xC4($a0) + lwc1 $f18, 0xC8($a0) + lwc1 $f19, 0xCC($a0) + lwc1 $f20, 0xD0($a0) + lwc1 $f21, 0xD4($a0) + lwc1 $f22, 0xD8($a0) + lwc1 $f23, 0xDC($a0) + lwc1 $f24, 0xE0($a0) + lwc1 $f25, 0xE4($a0) + lwc1 $f26, 0xE8($a0) + lwc1 $f27, 0xEC($a0) + lwc1 $f28, 0xF0($a0) + lwc1 $f29, 0xF4($a0) + lwc1 $f30, 0xF8($a0) + lwc1 $f31, 0xFC($a0) + " + }; +} + +#[naked] +pub extern "C-unwind" fn save_context(f: extern "C" fn(&mut Context, *mut ()), ptr: *mut ()) { + unsafe { + #[cfg(target_feature = "single-float")] + asm!( + " + .set noreorder + .set nomacro + .set noat + move $t0, $sp + add $sp, $sp, -0x110 + sw $ra, 0x100($sp) + ", + code!(save_gp), + code!(save_fp), + " + move $t9, $a0 + move $a0, $sp + /* jalr must use $t9 in PIE code */ + jalr $t9 + nop + lw $ra, 0x100($sp) + add $sp, $sp, 0x110 + jr $ra + nop + .set at + .set macro + .set reorder + ", + options(noreturn) + ); + #[cfg(not(target_feature = "single-float"))] + asm!( + " + .set noreorder + .set nomacro + .set noat + move $t0, $sp + add $sp, $sp, -0x90 + sw $ra, 0x80($sp) + ", + code!(save_gp), + " + move $t9, $a0 + move $a0, $sp + /* jalr must use $t9 in PIE code */ + jalr $t9 + nop + lw $ra, 0x80($sp) + add $sp, $sp, 0x90 + jr $ra + nop + .set at + .set macro + .set reorder + ", + options(noreturn) + ); + } +} + +pub unsafe extern "C" fn restore_context(ctx: &Context) -> ! { + unsafe { + #[cfg(target_feature = "single-float")] + asm!( + " + .set noreorder + .set nomacro + .set noat + ", + code!(restore_fp), + code!(restore_gp), + " + lw $a0, 0x10($a0) + jr $ra + nop + .set at + .set macro + .set reorder + ", + in("$a0") ctx, + options(noreturn) + ); + #[cfg(not(target_feature = "single-float"))] + asm!( + " + .set noreorder + .set nomacro + .set noat + ", + code!(restore_gp), + " + lw $a0, 0x10($a0) + jr $ra + nop + .set at + .set macro + .set reorder + ", + in("$a0") ctx, + options(noreturn) + ); + } +} diff --git a/src/unwinder/arch/mod.rs b/src/unwinder/arch/mod.rs index 8158353..80e401e 100644 --- a/src/unwinder/arch/mod.rs +++ b/src/unwinder/arch/mod.rs @@ -23,11 +23,17 @@ mod aarch64; #[cfg(target_arch = "aarch64")] pub use aarch64::*; +#[cfg(target_arch = "mips")] +mod mips; +#[cfg(target_arch = "mips")] +pub use mips::*; + #[cfg(not(any( target_arch = "x86_64", target_arch = "x86", target_arch = "riscv64", target_arch = "riscv32", - target_arch = "aarch64" + target_arch = "aarch64", + target_arch = "mips", )))] compile_error!("Current architecture is not supported");