1 files changed, 88 insertions, 0 deletions
diff --git a/third_party/rust/cranelift-codegen/src/isa/unwind.rs b/third_party/rust/cranelift-codegen/src/isa/unwind.rs
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index 0000000000..a4c5f0b6b7
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+++ b/third_party/rust/cranelift-codegen/src/isa/unwind.rs
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+//! Represents information relating to function unwinding.
+#[cfg(feature = "enable-serde")]
+use serde::{Deserialize, Serialize};
+
+#[cfg(feature = "unwind")]
+pub mod systemv;
+
+#[cfg(feature = "unwind")]
+pub mod winx64;
+
+/// Represents unwind information for a single function.
+#[derive(Clone, Debug, PartialEq, Eq)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
+#[non_exhaustive]
+pub enum UnwindInfo {
+    /// Windows x64 ABI unwind information.
+    #[cfg(feature = "unwind")]
+    WindowsX64(winx64::UnwindInfo),
+    /// System V ABI unwind information.
+    #[cfg(feature = "unwind")]
+    SystemV(systemv::UnwindInfo),
+}
+
+/// Intermediate representation for the unwind information
+/// generated by a backend.
+pub mod input {
+    use crate::binemit::CodeOffset;
+    use alloc::vec::Vec;
+    #[cfg(feature = "enable-serde")]
+    use serde::{Deserialize, Serialize};
+
+    /// Elementary operation in the unwind operations.
+    #[derive(Clone, Debug, PartialEq, Eq)]
+    #[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
+    pub enum UnwindCode<Reg> {
+        /// Defines that a register is saved at the specified offset.
+        SaveRegister {
+            /// The saved register.
+            reg: Reg,
+            /// The specified offset relative to the stack pointer.
+            stack_offset: u32,
+        },
+        /// Defines that a register is as defined before call.
+        RestoreRegister {
+            /// The restored register.
+            reg: Reg,
+        },
+        /// The stack pointer was adjusted to allocate the stack.
+        StackAlloc {
+            /// Size to allocate.
+            size: u32,
+        },
+        /// The stack pointer was adjusted to free the stack.
+        StackDealloc {
+            /// Size to deallocate.
+            size: u32,
+        },
+        /// The alternative register was assigned as frame pointer base.
+        SetFramePointer {
+            /// The specified register.
+            reg: Reg,
+        },
+        /// Restores a frame pointer base to default register.
+        RestoreFramePointer,
+        /// Saves the state.
+        RememberState,
+        /// Restores the state.
+        RestoreState,
+    }
+
+    /// Unwind information as generated by a backend.
+    #[derive(Clone, Debug, PartialEq, Eq)]
+    #[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
+    pub struct UnwindInfo<Reg> {
+        /// Size of the prologue.
+        pub prologue_size: CodeOffset,
+        /// Unwind codes for prologue.
+        pub prologue_unwind_codes: Vec<(CodeOffset, UnwindCode<Reg>)>,
+        /// Unwind codes for epilogues.
+        pub epilogues_unwind_codes: Vec<Vec<(CodeOffset, UnwindCode<Reg>)>>,
+        /// Entire function size.
+        pub function_size: CodeOffset,
+        /// Platform word size in bytes.
+        pub word_size: u8,
+        /// Initial stack pointer offset.
+        pub initial_sp_offset: u8,
+    }
+}