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Remove ancient register allocation (#3401)

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This commit is contained in:
Benjamin Bouvier
2021-09-30 21:27:23 +02:00
committed by GitHub
parent 80336f4535
commit bae4ec6427
66 changed files with 112 additions and 15380 deletions
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132
cranelift/codegen/src/isa/mod.rs
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@@ -44,26 +44,19 @@
//! concurrent function compilations.
pub use crate::isa::call_conv::CallConv;
pub use crate::isa::constraints::{
BranchRange, ConstraintKind, OperandConstraint, RecipeConstraints,
};
pub use crate::isa::enc_tables::Encodings;
pub use crate::isa::encoding::{base_size, EncInfo, Encoding};
pub use crate::isa::constraints::{BranchRange, ConstraintKind, OperandConstraint};
pub use crate::isa::registers::{regs_overlap, RegClass, RegClassIndex, RegInfo, RegUnit};
pub use crate::isa::stack::{StackBase, StackBaseMask, StackRef};
use crate::binemit;
use crate::flowgraph;
use crate::ir;
#[cfg(feature = "unwind")]
use crate::isa::unwind::systemv::RegisterMappingError;
use crate::machinst::{MachBackend, UnwindInfoKind};
use crate::regalloc;
use crate::result::CodegenResult;
use crate::settings;
use crate::settings::SetResult;
use crate::timing;
use alloc::{borrow::Cow, boxed::Box, vec::Vec};
use alloc::{boxed::Box, vec::Vec};
use core::any::Any;
use core::fmt;
use core::fmt::{Debug, Formatter};
@@ -88,8 +81,6 @@ pub mod unwind;
mod call_conv;
mod constraints;
mod enc_tables;
mod encoding;
pub mod registers;
mod stack;
@@ -329,125 +320,6 @@ pub trait TargetIsa: fmt::Display + Send + Sync {
Err(RegisterMappingError::UnsupportedArchitecture)
}
/// Returns an iterator over legal encodings for the instruction.
fn legal_encodings<'a>(
&'a self,
func: &'a ir::Function,
inst: &'a ir::InstructionData,
ctrl_typevar: ir::Type,
) -> Encodings<'a>;
/// Encode an instruction after determining it is legal.
///
/// If `inst` can legally be encoded in this ISA, produce the corresponding `Encoding` object.
/// Otherwise, return `Legalize` action.
///
/// This is also the main entry point for determining if an instruction is legal.
fn encode(
&self,
func: &ir::Function,
inst: &ir::InstructionData,
ctrl_typevar: ir::Type,
) -> Result<Encoding, Legalize> {
let mut iter = self.legal_encodings(func, inst, ctrl_typevar);
iter.next().ok_or_else(|| iter.legalize())
}
/// Get a data structure describing the instruction encodings in this ISA.
fn encoding_info(&self) -> EncInfo;
/// Legalize a function signature.
///
/// This is used to legalize both the signature of the function being compiled and any called
/// functions. The signature should be modified by adding `ArgumentLoc` annotations to all
/// arguments and return values.
///
/// Arguments with types that are not supported by the ABI can be expanded into multiple
/// arguments:
///
/// - Integer types that are too large to fit in a register can be broken into multiple
/// arguments of a smaller integer type.
/// - Floating point types can be bit-cast to an integer type of the same size, and possible
/// broken into smaller integer types.
/// - Vector types can be bit-cast and broken down into smaller vectors or scalars.
///
/// The legalizer will adapt argument and return values as necessary at all ABI boundaries.
///
/// When this function is called to legalize the signature of the function currently being
/// compiled, `current` is true. The legalized signature can then also contain special purpose
/// arguments and return values such as:
///
/// - A `link` argument representing the link registers on RISC architectures that don't push
/// the return address on the stack.
/// - A `link` return value which will receive the value that was passed to the `link`
/// argument.
/// - An `sret` argument can be added if one wasn't present already. This is necessary if the
/// signature returns more values than registers are available for returning values.
/// - An `sret` return value can be added if the ABI requires a function to return its `sret`
/// argument in a register.
///
/// Arguments and return values for the caller's frame pointer and other callee-saved registers
/// should not be added by this function. These arguments are not added until after register
/// allocation.
fn legalize_signature(&self, sig: &mut Cow<ir::Signature>, current: bool);
/// Get the register class that should be used to represent an ABI argument or return value of
/// type `ty`. This should be the top-level register class that contains the argument
/// registers.
///
/// This function can assume that it will only be asked to provide register classes for types
/// that `legalize_signature()` produces in `ArgumentLoc::Reg` entries.
fn regclass_for_abi_type(&self, ty: ir::Type) -> RegClass;
/// Get the set of allocatable registers that can be used when compiling `func`.
///
/// This set excludes reserved registers like the stack pointer and other special-purpose
/// registers.
fn allocatable_registers(&self, func: &ir::Function) -> regalloc::RegisterSet;
/// Compute the stack layout and insert prologue and epilogue code into `func`.
///
/// Return an error if the stack frame is too large.
fn prologue_epilogue(&self, func: &mut ir::Function) -> CodegenResult<()> {
let _tt = timing::prologue_epilogue();
// This default implementation is unlikely to be good enough.
use crate::ir::stackslot::{StackOffset, StackSize};
use crate::stack_layout::layout_stack;
let word_size = StackSize::from(self.pointer_bytes());
// Account for the SpiderMonkey standard prologue pushes.
if func.signature.call_conv.extends_baldrdash() {
let bytes = StackSize::from(self.flags().baldrdash_prologue_words()) * word_size;
let mut ss = ir::StackSlotData::new(ir::StackSlotKind::IncomingArg, bytes);
ss.offset = Some(-(bytes as StackOffset));
func.stack_slots.push(ss);
}
let is_leaf = func.is_leaf();
layout_stack(&mut func.stack_slots, is_leaf, word_size)?;
Ok(())
}
/// Emit binary machine code for a single instruction into the `sink` trait object.
///
/// Note that this will call `put*` methods on the `sink` trait object via its vtable which
/// is not the fastest way of emitting code.
///
/// This function is under the "testing_hooks" feature, and is only suitable for use by
/// test harnesses. It increases code size, and is inefficient.
#[cfg(feature = "testing_hooks")]
fn emit_inst(
&self,
func: &ir::Function,
inst: ir::Inst,
divert: &mut regalloc::RegDiversions,
sink: &mut dyn binemit::CodeSink,
);
/// Emit a whole function into memory.
fn emit_function_to_memory(&self, func: &ir::Function, sink: &mut binemit::MemoryCodeSink);
/// IntCC condition for Unsigned Addition Overflow (Carry).
fn unsigned_add_overflow_condition(&self) -> ir::condcodes::IntCC;