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Remove CodeSink

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This commit is contained in:
bjorn3
2022-01-11 17:10:37 +01:00
parent a48a60f958
commit 55d722db05
8 changed files with 23 additions and 103 deletions
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49
cranelift/codegen/src/binemit/memorysink.rs
View File

@@ -13,47 +13,9 @@
//! that a `MemoryCodeSink` will always write binary machine code to raw memory. It forwards any
//! relocations to a `RelocSink` trait object. Relocations are less frequent than the
//! `CodeSink::put*` methods, so the performance impact of the virtual callbacks is less severe.
use super::{Addend, CodeInfo, CodeOffset, CodeSink, Reloc};
use super::{Addend, CodeOffset, Reloc};
use crate::binemit::stack_map::StackMap;
use crate::ir::{ExternalName, SourceLoc, TrapCode};
use core::ptr::write_unaligned;
/// A `CodeSink` that writes binary machine code directly into memory.
///
/// A `MemoryCodeSink` object should be used when emitting a Cranelift IR function into executable
/// memory. It writes machine code directly to a raw pointer without any bounds checking, so make
/// sure to allocate enough memory for the whole function. The number of bytes required is returned
/// by the `Context::compile()` function.
///
/// Any relocations in the function are forwarded to the `RelocSink` trait object.
///
/// Note that `MemoryCodeSink` writes multi-byte values in the native byte order of the host. This
/// is not the right thing to do for cross compilation.
pub struct MemoryCodeSink {
/// Pointer to start of sink's preallocated memory.
data: *mut u8,
/// Offset is isize because its major consumer needs it in that form.
offset: isize,
}
impl<'a> MemoryCodeSink {
/// Create a new memory code sink that writes a function to the memory pointed to by `data`.
///
/// # Safety
///
/// This function is unsafe since `MemoryCodeSink` does not perform bounds checking on the
/// memory buffer, and it can't guarantee that the `data` pointer is valid.
pub unsafe fn new(data: *mut u8) -> Self {
Self { data, offset: 0 }
}
/// Information about the generated code and read-only data.
pub fn info(&self) -> CodeInfo {
CodeInfo {
total_size: self.offset as CodeOffset,
}
}
}
/// A trait for receiving relocations for code that is emitted directly into memory.
pub trait RelocSink {
@@ -77,15 +39,6 @@ pub trait TrapSink {
fn trap(&mut self, _: CodeOffset, _: SourceLoc, _: TrapCode);
}
impl CodeSink for MemoryCodeSink {
fn put1(&mut self, x: u8) {
unsafe {
write_unaligned(self.data.offset(self.offset), x);
self.offset += 1;
}
}
}
/// A `RelocSink` implementation that does nothing, which is convenient when
/// compiling code that does not relocate anything.
#[derive(Default)]

12
cranelift/codegen/src/binemit/mod.rs
View File

@@ -7,8 +7,7 @@ mod memorysink;
mod stack_map;
pub use self::memorysink::{
MemoryCodeSink, NullRelocSink, NullStackMapSink, NullTrapSink, RelocSink, StackMapSink,
TrapSink,
NullRelocSink, NullStackMapSink, NullTrapSink, RelocSink, StackMapSink, TrapSink,
};
pub use self::stack_map::StackMap;
use core::fmt;
@@ -98,12 +97,3 @@ pub struct CodeInfo {
/// Number of bytes in total.
pub total_size: CodeOffset,
}
/// Abstract interface for adding bytes to the code segment.
///
/// A `CodeSink` will receive all of the machine code for a function. It also accepts relocations
/// which are locations in the code section that need to be fixed up when linking.
pub trait CodeSink {
/// Add 1 byte to the code section.
fn put1(&mut self, _: u8);
}