libunwind: add rust interface

artiq/firmware/libunwind/Cargo.toml

@@ -0,0 +1,30 @@
+[package]
+authors = ["The Rust Project Developers"]
+name = "unwind"
+version = "0.0.0"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-lang/rust.git"
+edition = "2018"
+include = [
+  '/libunwind/*',
+]
+
+[lib]
+test = false
+bench = false
+doc = false
+
+[dependencies]
+libc = { path = "../libc" }
+cfg-if = "0.1.8"
+
+[features]
+
+# Only applies for Linux and Fuchsia targets
+# Static link to the in-tree build of llvm libunwind
+llvm-libunwind = []
+
+# Only applies for Linux and Fuchsia targets
+# If crt-static is enabled, static link to `libunwind.a` provided by system
+# If crt-static is disabled, dynamic link to `libunwind.so` provided by system
+system-llvm-libunwind = []

artiq/firmware/libunwind/src/lib.rs

@@ -0,0 +1,11 @@
+#![no_std]
+#![unstable(feature = "panic_unwind", issue = "32837")]
+#![feature(link_cfg)]
+#![feature(nll)]
+#![feature(staged_api)]
+#![feature(unwind_attributes)]
+#![feature(static_nobundle)]
+#![cfg_attr(not(target_env = "msvc"), feature(libc))]
+
+mod libunwind;
+pub use libunwind::*;

artiq/firmware/libunwind/src/libunwind.rs

@@ -0,0 +1,282 @@
+#![allow(nonstandard_style)]
+
+use libc::{c_int, c_void, uintptr_t};
+
+#[repr(C)]
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub enum _Unwind_Reason_Code {
+    _URC_NO_REASON = 0,
+    _URC_FOREIGN_EXCEPTION_CAUGHT = 1,
+    _URC_FATAL_PHASE2_ERROR = 2,
+    _URC_FATAL_PHASE1_ERROR = 3,
+    _URC_NORMAL_STOP = 4,
+    _URC_END_OF_STACK = 5,
+    _URC_HANDLER_FOUND = 6,
+    _URC_INSTALL_CONTEXT = 7,
+    _URC_CONTINUE_UNWIND = 8,
+    _URC_FAILURE = 9, // used only by ARM EHABI
+}
+pub use _Unwind_Reason_Code::*;
+
+pub type _Unwind_Exception_Class = u64;
+pub type _Unwind_Word = uintptr_t;
+pub type _Unwind_Ptr = uintptr_t;
+pub type _Unwind_Trace_Fn =
+    extern "C" fn(ctx: *mut _Unwind_Context, arg: *mut c_void) -> _Unwind_Reason_Code;
+
+#[cfg(target_arch = "x86")]
+pub const unwinder_private_data_size: usize = 5;
+
+#[cfg(target_arch = "x86_64")]
+pub const unwinder_private_data_size: usize = 6;
+
+#[cfg(all(target_arch = "arm", not(target_os = "ios")))]
+pub const unwinder_private_data_size: usize = 20;
+
+#[cfg(all(target_arch = "arm", target_os = "ios"))]
+pub const unwinder_private_data_size: usize = 5;
+
+#[cfg(all(target_arch = "aarch64", target_pointer_width = "64"))]
+pub const unwinder_private_data_size: usize = 2;
+
+#[cfg(all(target_arch = "aarch64", target_pointer_width = "32"))]
+pub const unwinder_private_data_size: usize = 5;
+
+#[cfg(target_arch = "mips")]
+pub const unwinder_private_data_size: usize = 2;
+
+#[cfg(target_arch = "mips64")]
+pub const unwinder_private_data_size: usize = 2;
+
+#[cfg(any(target_arch = "powerpc", target_arch = "powerpc64"))]
+pub const unwinder_private_data_size: usize = 2;
+
+#[cfg(target_arch = "s390x")]
+pub const unwinder_private_data_size: usize = 2;
+
+#[cfg(any(target_arch = "sparc", target_arch = "sparc64"))]
+pub const unwinder_private_data_size: usize = 2;
+
+#[cfg(any(target_arch = "riscv64", target_arch = "riscv32"))]
+pub const unwinder_private_data_size: usize = 2;
+
+#[cfg(target_os = "emscripten")]
+pub const unwinder_private_data_size: usize = 20;
+
+#[cfg(all(target_arch = "hexagon", target_os = "linux"))]
+pub const unwinder_private_data_size: usize = 35;
+
+#[repr(C)]
+pub struct _Unwind_Exception {
+    pub exception_class: _Unwind_Exception_Class,
+    pub exception_cleanup: _Unwind_Exception_Cleanup_Fn,
+    pub private: [_Unwind_Word; unwinder_private_data_size],
+}
+
+pub enum _Unwind_Context {}
+
+pub type _Unwind_Exception_Cleanup_Fn =
+    extern "C" fn(unwind_code: _Unwind_Reason_Code, exception: *mut _Unwind_Exception);
+#[cfg_attr(
+    all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux")),
+    link(name = "unwind", kind = "static")
+)]
+extern "C" {
+    #[unwind(allowed)]
+    pub fn _Unwind_Resume(exception: *mut _Unwind_Exception) -> !;
+    pub fn _Unwind_DeleteException(exception: *mut _Unwind_Exception);
+    pub fn _Unwind_GetLanguageSpecificData(ctx: *mut _Unwind_Context) -> *mut c_void;
+    pub fn _Unwind_GetRegionStart(ctx: *mut _Unwind_Context) -> _Unwind_Ptr;
+    pub fn _Unwind_GetTextRelBase(ctx: *mut _Unwind_Context) -> _Unwind_Ptr;
+    pub fn _Unwind_GetDataRelBase(ctx: *mut _Unwind_Context) -> _Unwind_Ptr;
+}
+
+cfg_if::cfg_if! {
+if #[cfg(any(target_os = "ios", target_os = "netbsd", not(target_arch = "arm")))] {
+    // Not ARM EHABI
+    #[repr(C)]
+    #[derive(Copy, Clone, PartialEq)]
+    pub enum _Unwind_Action {
+        _UA_SEARCH_PHASE = 1,
+        _UA_CLEANUP_PHASE = 2,
+        _UA_HANDLER_FRAME = 4,
+        _UA_FORCE_UNWIND = 8,
+        _UA_END_OF_STACK = 16,
+    }
+    pub use _Unwind_Action::*;
+
+    #[cfg_attr(all(feature = "llvm-libunwind",
+                   any(target_os = "fuchsia", target_os = "linux")),
+               link(name = "unwind", kind = "static"))]
+    extern "C" {
+        pub fn _Unwind_GetGR(ctx: *mut _Unwind_Context, reg_index: c_int) -> _Unwind_Word;
+        pub fn _Unwind_SetGR(ctx: *mut _Unwind_Context, reg_index: c_int, value: _Unwind_Word);
+        pub fn _Unwind_GetIP(ctx: *mut _Unwind_Context) -> _Unwind_Word;
+        pub fn _Unwind_SetIP(ctx: *mut _Unwind_Context, value: _Unwind_Word);
+        pub fn _Unwind_GetIPInfo(ctx: *mut _Unwind_Context, ip_before_insn: *mut c_int)
+                                 -> _Unwind_Word;
+        pub fn _Unwind_FindEnclosingFunction(pc: *mut c_void) -> *mut c_void;
+    }
+
+} else {
+    // ARM EHABI
+    #[repr(C)]
+    #[derive(Copy, Clone, PartialEq)]
+    pub enum _Unwind_State {
+        _US_VIRTUAL_UNWIND_FRAME = 0,
+        _US_UNWIND_FRAME_STARTING = 1,
+        _US_UNWIND_FRAME_RESUME = 2,
+        _US_ACTION_MASK = 3,
+        _US_FORCE_UNWIND = 8,
+        _US_END_OF_STACK = 16,
+    }
+    pub use _Unwind_State::*;
+
+    #[repr(C)]
+    enum _Unwind_VRS_Result {
+        _UVRSR_OK = 0,
+        _UVRSR_NOT_IMPLEMENTED = 1,
+        _UVRSR_FAILED = 2,
+    }
+    #[repr(C)]
+    enum _Unwind_VRS_RegClass {
+        _UVRSC_CORE = 0,
+        _UVRSC_VFP = 1,
+        _UVRSC_FPA = 2,
+        _UVRSC_WMMXD = 3,
+        _UVRSC_WMMXC = 4,
+    }
+    use _Unwind_VRS_RegClass::*;
+    #[repr(C)]
+    enum _Unwind_VRS_DataRepresentation {
+        _UVRSD_UINT32 = 0,
+        _UVRSD_VFPX = 1,
+        _UVRSD_FPAX = 2,
+        _UVRSD_UINT64 = 3,
+        _UVRSD_FLOAT = 4,
+        _UVRSD_DOUBLE = 5,
+    }
+    use _Unwind_VRS_DataRepresentation::*;
+
+    pub const UNWIND_POINTER_REG: c_int = 12;
+    pub const UNWIND_SP_REG: c_int = 13;
+    pub const UNWIND_IP_REG: c_int = 15;
+
+    #[cfg_attr(all(feature = "llvm-libunwind",
+                   any(target_os = "fuchsia", target_os = "linux")),
+               link(name = "unwind", kind = "static"))]
+    extern "C" {
+        fn _Unwind_VRS_Get(ctx: *mut _Unwind_Context,
+                           regclass: _Unwind_VRS_RegClass,
+                           regno: _Unwind_Word,
+                           repr: _Unwind_VRS_DataRepresentation,
+                           data: *mut c_void)
+                           -> _Unwind_VRS_Result;
+
+        fn _Unwind_VRS_Set(ctx: *mut _Unwind_Context,
+                           regclass: _Unwind_VRS_RegClass,
+                           regno: _Unwind_Word,
+                           repr: _Unwind_VRS_DataRepresentation,
+                           data: *mut c_void)
+                           -> _Unwind_VRS_Result;
+    }
+
+    // On Android or ARM/Linux, these are implemented as macros:
+
+    pub unsafe fn _Unwind_GetGR(ctx: *mut _Unwind_Context, reg_index: c_int) -> _Unwind_Word {
+        let mut val: _Unwind_Word = 0;
+        _Unwind_VRS_Get(ctx, _UVRSC_CORE, reg_index as _Unwind_Word, _UVRSD_UINT32,
+                        &mut val as *mut _ as *mut c_void);
+        val
+    }
+
+    pub unsafe fn _Unwind_SetGR(ctx: *mut _Unwind_Context, reg_index: c_int, value: _Unwind_Word) {
+        let mut value = value;
+        _Unwind_VRS_Set(ctx, _UVRSC_CORE, reg_index as _Unwind_Word, _UVRSD_UINT32,
+                        &mut value as *mut _ as *mut c_void);
+    }
+
+    pub unsafe fn _Unwind_GetIP(ctx: *mut _Unwind_Context)
+                                -> _Unwind_Word {
+        let val = _Unwind_GetGR(ctx, UNWIND_IP_REG);
+        (val & !1) as _Unwind_Word
+    }
+
+    pub unsafe fn _Unwind_SetIP(ctx: *mut _Unwind_Context,
+                                value: _Unwind_Word) {
+        // Propagate thumb bit to instruction pointer
+        let thumb_state = _Unwind_GetGR(ctx, UNWIND_IP_REG) & 1;
+        let value = value | thumb_state;
+        _Unwind_SetGR(ctx, UNWIND_IP_REG, value);
+    }
+
+    pub unsafe fn _Unwind_GetIPInfo(ctx: *mut _Unwind_Context,
+                                    ip_before_insn: *mut c_int)
+                                    -> _Unwind_Word {
+        *ip_before_insn = 0;
+        _Unwind_GetIP(ctx)
+    }
+
+    // This function also doesn't exist on Android or ARM/Linux, so make it a no-op
+    pub unsafe fn _Unwind_FindEnclosingFunction(pc: *mut c_void) -> *mut c_void {
+        pc
+    }
+}
+} // cfg_if!
+
+cfg_if::cfg_if! {
+if #[cfg(not(all(target_os = "ios", target_arch = "arm")))] {
+    // Not 32-bit iOS
+    #[cfg_attr(all(feature = "llvm-libunwind",
+                   any(target_os = "fuchsia", target_os = "linux")),
+               link(name = "unwind", kind = "static"))]
+    extern "C" {
+        #[unwind(allowed)]
+        pub fn _Unwind_RaiseException(exception: *mut _Unwind_Exception) -> _Unwind_Reason_Code;
+        pub fn _Unwind_Backtrace(trace: _Unwind_Trace_Fn,
+                                 trace_argument: *mut c_void)
+                                 -> _Unwind_Reason_Code;
+    }
+} else {
+    // 32-bit iOS uses SjLj and does not provide _Unwind_Backtrace()
+    #[cfg_attr(all(feature = "llvm-libunwind",
+                   any(target_os = "fuchsia", target_os = "linux")),
+               link(name = "unwind", kind = "static"))]
+    extern "C" {
+        #[unwind(allowed)]
+        pub fn _Unwind_SjLj_RaiseException(e: *mut _Unwind_Exception) -> _Unwind_Reason_Code;
+    }
+
+    #[inline]
+    pub unsafe fn _Unwind_RaiseException(exc: *mut _Unwind_Exception) -> _Unwind_Reason_Code {
+        _Unwind_SjLj_RaiseException(exc)
+    }
+}
+} // cfg_if!
+
+cfg_if::cfg_if! {
+if #[cfg(all(windows, target_arch = "x86_64", target_env = "gnu"))] {
+    // We declare these as opaque types. This is fine since you just need to
+    // pass them to _GCC_specific_handler and forget about them.
+    pub enum EXCEPTION_RECORD {}
+    pub type LPVOID = *mut c_void;
+    pub enum CONTEXT {}
+    pub enum DISPATCHER_CONTEXT {}
+    pub type EXCEPTION_DISPOSITION = c_int;
+    type PersonalityFn = unsafe extern "C" fn(version: c_int,
+                                              actions: _Unwind_Action,
+                                              exception_class: _Unwind_Exception_Class,
+                                              exception_object: *mut _Unwind_Exception,
+                                              context: *mut _Unwind_Context)
+                                              -> _Unwind_Reason_Code;
+
+    extern "C" {
+        pub fn _GCC_specific_handler(exceptionRecord: *mut EXCEPTION_RECORD,
+                                establisherFrame: LPVOID,
+                                contextRecord: *mut CONTEXT,
+                                dispatcherContext: *mut DISPATCHER_CONTEXT,
+                                personality: PersonalityFn)
+                                -> EXCEPTION_DISPOSITION;
+    }
+}
+} // cfg_if!