mirror of
https://github.com/rust-lang/rust.git
synced 2025-10-30 20:44:34 +00:00
1074 lines
43 KiB
Rust
1074 lines
43 KiB
Rust
//! Codegen of a single function
|
|
|
|
use rustc_index::vec::IndexVec;
|
|
use rustc_middle::ty::adjustment::PointerCast;
|
|
use rustc_middle::ty::layout::FnAbiExt;
|
|
use rustc_target::abi::call::FnAbi;
|
|
|
|
use crate::prelude::*;
|
|
|
|
pub(crate) fn codegen_fn<'tcx>(
|
|
cx: &mut crate::CodegenCx<'tcx, impl Module>,
|
|
instance: Instance<'tcx>,
|
|
linkage: Linkage,
|
|
) {
|
|
let tcx = cx.tcx;
|
|
|
|
let _inst_guard =
|
|
crate::PrintOnPanic(|| format!("{:?} {}", instance, tcx.symbol_name(instance).name));
|
|
debug_assert!(!instance.substs.needs_infer());
|
|
|
|
let mir = tcx.instance_mir(instance.def);
|
|
|
|
// Declare function
|
|
let name = tcx.symbol_name(instance).name.to_string();
|
|
let sig = get_function_sig(tcx, cx.module.isa().triple(), instance);
|
|
let func_id = cx.module.declare_function(&name, linkage, &sig).unwrap();
|
|
|
|
cx.cached_context.clear();
|
|
|
|
// Make the FunctionBuilder
|
|
let mut func_ctx = FunctionBuilderContext::new();
|
|
let mut func = std::mem::replace(&mut cx.cached_context.func, Function::new());
|
|
func.name = ExternalName::user(0, func_id.as_u32());
|
|
func.signature = sig;
|
|
func.collect_debug_info();
|
|
|
|
let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
|
|
|
|
// Predefine blocks
|
|
let start_block = bcx.create_block();
|
|
let block_map: IndexVec<BasicBlock, Block> = (0..mir.basic_blocks().len())
|
|
.map(|_| bcx.create_block())
|
|
.collect();
|
|
|
|
// Make FunctionCx
|
|
let pointer_type = cx.module.target_config().pointer_type();
|
|
let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
|
|
|
|
let mut fx = FunctionCx {
|
|
cx,
|
|
tcx,
|
|
pointer_type,
|
|
|
|
instance,
|
|
mir,
|
|
fn_abi: Some(FnAbi::of_instance(&RevealAllLayoutCx(tcx), instance, &[])),
|
|
|
|
bcx,
|
|
block_map,
|
|
local_map: IndexVec::with_capacity(mir.local_decls.len()),
|
|
caller_location: None, // set by `codegen_fn_prelude`
|
|
cold_blocks: EntitySet::new(),
|
|
|
|
clif_comments,
|
|
source_info_set: indexmap::IndexSet::new(),
|
|
next_ssa_var: 0,
|
|
|
|
inline_asm_index: 0,
|
|
};
|
|
|
|
let arg_uninhabited = fx.mir.args_iter().any(|arg| {
|
|
fx.layout_of(fx.monomorphize(&fx.mir.local_decls[arg].ty))
|
|
.abi
|
|
.is_uninhabited()
|
|
});
|
|
|
|
if arg_uninhabited {
|
|
fx.bcx
|
|
.append_block_params_for_function_params(fx.block_map[START_BLOCK]);
|
|
fx.bcx.switch_to_block(fx.block_map[START_BLOCK]);
|
|
crate::trap::trap_unreachable(&mut fx, "function has uninhabited argument");
|
|
} else {
|
|
tcx.sess.time("codegen clif ir", || {
|
|
tcx.sess.time("codegen prelude", || {
|
|
crate::abi::codegen_fn_prelude(&mut fx, start_block)
|
|
});
|
|
codegen_fn_content(&mut fx);
|
|
});
|
|
}
|
|
|
|
// Recover all necessary data from fx, before accessing func will prevent future access to it.
|
|
let instance = fx.instance;
|
|
let mut clif_comments = fx.clif_comments;
|
|
let source_info_set = fx.source_info_set;
|
|
let local_map = fx.local_map;
|
|
let cold_blocks = fx.cold_blocks;
|
|
|
|
// Store function in context
|
|
let context = &mut cx.cached_context;
|
|
context.func = func;
|
|
|
|
crate::pretty_clif::write_clif_file(tcx, "unopt", None, instance, &context, &clif_comments);
|
|
|
|
// Verify function
|
|
verify_func(tcx, &clif_comments, &context.func);
|
|
|
|
// Perform rust specific optimizations
|
|
tcx.sess.time("optimize clif ir", || {
|
|
crate::optimize::optimize_function(
|
|
tcx,
|
|
instance,
|
|
context,
|
|
&cold_blocks,
|
|
&mut clif_comments,
|
|
);
|
|
});
|
|
|
|
// If the return block is not reachable, then the SSA builder may have inserted an `iconst.i128`
|
|
// instruction, which doesn't have an encoding.
|
|
context.compute_cfg();
|
|
context.compute_domtree();
|
|
context.eliminate_unreachable_code(cx.module.isa()).unwrap();
|
|
context.dce(cx.module.isa()).unwrap();
|
|
// Some Cranelift optimizations expect the domtree to not yet be computed and as such don't
|
|
// invalidate it when it would change.
|
|
context.domtree.clear();
|
|
|
|
context.want_disasm = crate::pretty_clif::should_write_ir(tcx);
|
|
|
|
// Define function
|
|
let module = &mut cx.module;
|
|
tcx.sess.time("define function", || {
|
|
module
|
|
.define_function(
|
|
func_id,
|
|
context,
|
|
&mut cranelift_codegen::binemit::NullTrapSink {},
|
|
)
|
|
.unwrap()
|
|
});
|
|
|
|
// Write optimized function to file for debugging
|
|
crate::pretty_clif::write_clif_file(
|
|
tcx,
|
|
"opt",
|
|
Some(cx.module.isa()),
|
|
instance,
|
|
&context,
|
|
&clif_comments,
|
|
);
|
|
|
|
if let Some(mach_compile_result) = &context.mach_compile_result {
|
|
if let Some(disasm) = &mach_compile_result.disasm {
|
|
crate::pretty_clif::write_ir_file(
|
|
tcx,
|
|
&format!("{}.vcode", tcx.symbol_name(instance).name),
|
|
|file| file.write_all(disasm.as_bytes()),
|
|
)
|
|
}
|
|
}
|
|
|
|
// Define debuginfo for function
|
|
let isa = cx.module.isa();
|
|
let debug_context = &mut cx.debug_context;
|
|
let unwind_context = &mut cx.unwind_context;
|
|
tcx.sess.time("generate debug info", || {
|
|
if let Some(debug_context) = debug_context {
|
|
debug_context.define_function(
|
|
instance,
|
|
func_id,
|
|
&name,
|
|
isa,
|
|
context,
|
|
&source_info_set,
|
|
local_map,
|
|
);
|
|
}
|
|
unwind_context.add_function(func_id, &context, isa);
|
|
});
|
|
|
|
// Clear context to make it usable for the next function
|
|
context.clear();
|
|
}
|
|
|
|
pub(crate) fn verify_func(
|
|
tcx: TyCtxt<'_>,
|
|
writer: &crate::pretty_clif::CommentWriter,
|
|
func: &Function,
|
|
) {
|
|
tcx.sess.time("verify clif ir", || {
|
|
let flags = cranelift_codegen::settings::Flags::new(cranelift_codegen::settings::builder());
|
|
match cranelift_codegen::verify_function(&func, &flags) {
|
|
Ok(_) => {}
|
|
Err(err) => {
|
|
tcx.sess.err(&format!("{:?}", err));
|
|
let pretty_error = cranelift_codegen::print_errors::pretty_verifier_error(
|
|
&func,
|
|
None,
|
|
Some(Box::new(writer)),
|
|
err,
|
|
);
|
|
tcx.sess
|
|
.fatal(&format!("cranelift verify error:\n{}", pretty_error));
|
|
}
|
|
}
|
|
});
|
|
}
|
|
|
|
fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Module>) {
|
|
crate::constant::check_constants(fx);
|
|
|
|
for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
|
|
let block = fx.get_block(bb);
|
|
fx.bcx.switch_to_block(block);
|
|
|
|
if bb_data.is_cleanup {
|
|
// Unwinding after panicking is not supported
|
|
continue;
|
|
|
|
// FIXME once unwinding is supported uncomment next lines
|
|
// // Unwinding is unlikely to happen, so mark cleanup block's as cold.
|
|
// fx.cold_blocks.insert(block);
|
|
}
|
|
|
|
fx.bcx.ins().nop();
|
|
for stmt in &bb_data.statements {
|
|
fx.set_debug_loc(stmt.source_info);
|
|
codegen_stmt(fx, block, stmt);
|
|
}
|
|
|
|
#[cfg(debug_assertions)]
|
|
{
|
|
let mut terminator_head = "\n".to_string();
|
|
bb_data
|
|
.terminator()
|
|
.kind
|
|
.fmt_head(&mut terminator_head)
|
|
.unwrap();
|
|
let inst = fx.bcx.func.layout.last_inst(block).unwrap();
|
|
fx.add_comment(inst, terminator_head);
|
|
}
|
|
|
|
fx.set_debug_loc(bb_data.terminator().source_info);
|
|
|
|
match &bb_data.terminator().kind {
|
|
TerminatorKind::Goto { target } => {
|
|
if let TerminatorKind::Return = fx.mir[*target].terminator().kind {
|
|
let mut can_immediately_return = true;
|
|
for stmt in &fx.mir[*target].statements {
|
|
if let StatementKind::StorageDead(_) = stmt.kind {
|
|
} else {
|
|
// FIXME Can sometimes happen, see rust-lang/rust#70531
|
|
can_immediately_return = false;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if can_immediately_return {
|
|
crate::abi::codegen_return(fx);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
let block = fx.get_block(*target);
|
|
fx.bcx.ins().jump(block, &[]);
|
|
}
|
|
TerminatorKind::Return => {
|
|
crate::abi::codegen_return(fx);
|
|
}
|
|
TerminatorKind::Assert {
|
|
cond,
|
|
expected,
|
|
msg,
|
|
target,
|
|
cleanup: _,
|
|
} => {
|
|
if !fx.tcx.sess.overflow_checks() {
|
|
if let mir::AssertKind::OverflowNeg(_) = *msg {
|
|
let target = fx.get_block(*target);
|
|
fx.bcx.ins().jump(target, &[]);
|
|
continue;
|
|
}
|
|
}
|
|
let cond = codegen_operand(fx, cond).load_scalar(fx);
|
|
|
|
let target = fx.get_block(*target);
|
|
let failure = fx.bcx.create_block();
|
|
fx.cold_blocks.insert(failure);
|
|
|
|
if *expected {
|
|
fx.bcx.ins().brz(cond, failure, &[]);
|
|
} else {
|
|
fx.bcx.ins().brnz(cond, failure, &[]);
|
|
};
|
|
fx.bcx.ins().jump(target, &[]);
|
|
|
|
fx.bcx.switch_to_block(failure);
|
|
fx.bcx.ins().nop();
|
|
|
|
match msg {
|
|
AssertKind::BoundsCheck { ref len, ref index } => {
|
|
let len = codegen_operand(fx, len).load_scalar(fx);
|
|
let index = codegen_operand(fx, index).load_scalar(fx);
|
|
let location = fx
|
|
.get_caller_location(bb_data.terminator().source_info.span)
|
|
.load_scalar(fx);
|
|
|
|
codegen_panic_inner(
|
|
fx,
|
|
rustc_hir::LangItem::PanicBoundsCheck,
|
|
&[index, len, location],
|
|
bb_data.terminator().source_info.span,
|
|
);
|
|
}
|
|
_ => {
|
|
let msg_str = msg.description();
|
|
codegen_panic(fx, msg_str, bb_data.terminator().source_info.span);
|
|
}
|
|
}
|
|
}
|
|
|
|
TerminatorKind::SwitchInt {
|
|
discr,
|
|
switch_ty,
|
|
targets,
|
|
} => {
|
|
let discr = codegen_operand(fx, discr).load_scalar(fx);
|
|
|
|
let use_bool_opt = switch_ty.kind() == fx.tcx.types.bool.kind()
|
|
|| (targets.iter().count() == 1 && targets.iter().next().unwrap().0 == 0);
|
|
if use_bool_opt {
|
|
assert_eq!(targets.iter().count(), 1);
|
|
let (then_value, then_block) = targets.iter().next().unwrap();
|
|
let then_block = fx.get_block(then_block);
|
|
let else_block = fx.get_block(targets.otherwise());
|
|
let test_zero = match then_value {
|
|
0 => true,
|
|
1 => false,
|
|
_ => unreachable!("{:?}", targets),
|
|
};
|
|
|
|
let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
|
|
let (discr, is_inverted) =
|
|
crate::optimize::peephole::maybe_unwrap_bool_not(&mut fx.bcx, discr);
|
|
let test_zero = if is_inverted { !test_zero } else { test_zero };
|
|
let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
|
|
let discr =
|
|
crate::optimize::peephole::make_branchable_value(&mut fx.bcx, discr);
|
|
if let Some(taken) = crate::optimize::peephole::maybe_known_branch_taken(
|
|
&fx.bcx, discr, test_zero,
|
|
) {
|
|
if taken {
|
|
fx.bcx.ins().jump(then_block, &[]);
|
|
} else {
|
|
fx.bcx.ins().jump(else_block, &[]);
|
|
}
|
|
} else {
|
|
if test_zero {
|
|
fx.bcx.ins().brz(discr, then_block, &[]);
|
|
fx.bcx.ins().jump(else_block, &[]);
|
|
} else {
|
|
fx.bcx.ins().brnz(discr, then_block, &[]);
|
|
fx.bcx.ins().jump(else_block, &[]);
|
|
}
|
|
}
|
|
} else {
|
|
let mut switch = ::cranelift_frontend::Switch::new();
|
|
for (value, block) in targets.iter() {
|
|
let block = fx.get_block(block);
|
|
switch.set_entry(value, block);
|
|
}
|
|
let otherwise_block = fx.get_block(targets.otherwise());
|
|
switch.emit(&mut fx.bcx, discr, otherwise_block);
|
|
}
|
|
}
|
|
TerminatorKind::Call {
|
|
func,
|
|
args,
|
|
destination,
|
|
fn_span,
|
|
cleanup: _,
|
|
from_hir_call: _,
|
|
} => {
|
|
fx.tcx.sess.time("codegen call", || {
|
|
crate::abi::codegen_terminator_call(
|
|
fx,
|
|
*fn_span,
|
|
block,
|
|
func,
|
|
args,
|
|
*destination,
|
|
)
|
|
});
|
|
}
|
|
TerminatorKind::InlineAsm {
|
|
template,
|
|
operands,
|
|
options,
|
|
destination,
|
|
line_spans: _,
|
|
} => {
|
|
crate::inline_asm::codegen_inline_asm(
|
|
fx,
|
|
bb_data.terminator().source_info.span,
|
|
template,
|
|
operands,
|
|
*options,
|
|
);
|
|
|
|
match *destination {
|
|
Some(destination) => {
|
|
let destination_block = fx.get_block(destination);
|
|
fx.bcx.ins().jump(destination_block, &[]);
|
|
}
|
|
None => {
|
|
crate::trap::trap_unreachable(
|
|
fx,
|
|
"[corruption] Returned from noreturn inline asm",
|
|
);
|
|
}
|
|
}
|
|
}
|
|
TerminatorKind::Resume | TerminatorKind::Abort => {
|
|
trap_unreachable(fx, "[corruption] Unwinding bb reached.");
|
|
}
|
|
TerminatorKind::Unreachable => {
|
|
trap_unreachable(fx, "[corruption] Hit unreachable code.");
|
|
}
|
|
TerminatorKind::Yield { .. }
|
|
| TerminatorKind::FalseEdge { .. }
|
|
| TerminatorKind::FalseUnwind { .. }
|
|
| TerminatorKind::DropAndReplace { .. }
|
|
| TerminatorKind::GeneratorDrop => {
|
|
bug!("shouldn't exist at codegen {:?}", bb_data.terminator());
|
|
}
|
|
TerminatorKind::Drop {
|
|
place,
|
|
target,
|
|
unwind: _,
|
|
} => {
|
|
let drop_place = codegen_place(fx, *place);
|
|
crate::abi::codegen_drop(fx, bb_data.terminator().source_info.span, drop_place);
|
|
|
|
let target_block = fx.get_block(*target);
|
|
fx.bcx.ins().jump(target_block, &[]);
|
|
}
|
|
};
|
|
}
|
|
|
|
fx.bcx.seal_all_blocks();
|
|
fx.bcx.finalize();
|
|
}
|
|
|
|
fn codegen_stmt<'tcx>(
|
|
fx: &mut FunctionCx<'_, 'tcx, impl Module>,
|
|
#[allow(unused_variables)] cur_block: Block,
|
|
stmt: &Statement<'tcx>,
|
|
) {
|
|
let _print_guard = crate::PrintOnPanic(|| format!("stmt {:?}", stmt));
|
|
|
|
fx.set_debug_loc(stmt.source_info);
|
|
|
|
#[cfg(false_debug_assertions)]
|
|
match &stmt.kind {
|
|
StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
|
|
_ => {
|
|
let inst = fx.bcx.func.layout.last_inst(cur_block).unwrap();
|
|
fx.add_comment(inst, format!("{:?}", stmt));
|
|
}
|
|
}
|
|
|
|
match &stmt.kind {
|
|
StatementKind::SetDiscriminant {
|
|
place,
|
|
variant_index,
|
|
} => {
|
|
let place = codegen_place(fx, **place);
|
|
crate::discriminant::codegen_set_discriminant(fx, place, *variant_index);
|
|
}
|
|
StatementKind::Assign(to_place_and_rval) => {
|
|
let lval = codegen_place(fx, to_place_and_rval.0);
|
|
let dest_layout = lval.layout();
|
|
match to_place_and_rval.1 {
|
|
Rvalue::Use(ref operand) => {
|
|
let val = codegen_operand(fx, operand);
|
|
lval.write_cvalue(fx, val);
|
|
}
|
|
Rvalue::Ref(_, _, place) | Rvalue::AddressOf(_, place) => {
|
|
let place = codegen_place(fx, place);
|
|
let ref_ = place.place_ref(fx, lval.layout());
|
|
lval.write_cvalue(fx, ref_);
|
|
}
|
|
Rvalue::ThreadLocalRef(def_id) => {
|
|
let val = crate::constant::codegen_tls_ref(fx, def_id, lval.layout());
|
|
lval.write_cvalue(fx, val);
|
|
}
|
|
Rvalue::BinaryOp(bin_op, ref lhs, ref rhs) => {
|
|
let lhs = codegen_operand(fx, lhs);
|
|
let rhs = codegen_operand(fx, rhs);
|
|
|
|
let res = crate::num::codegen_binop(fx, bin_op, lhs, rhs);
|
|
lval.write_cvalue(fx, res);
|
|
}
|
|
Rvalue::CheckedBinaryOp(bin_op, ref lhs, ref rhs) => {
|
|
let lhs = codegen_operand(fx, lhs);
|
|
let rhs = codegen_operand(fx, rhs);
|
|
|
|
let res = if !fx.tcx.sess.overflow_checks() {
|
|
let val =
|
|
crate::num::codegen_int_binop(fx, bin_op, lhs, rhs).load_scalar(fx);
|
|
let is_overflow = fx.bcx.ins().iconst(types::I8, 0);
|
|
CValue::by_val_pair(val, is_overflow, lval.layout())
|
|
} else {
|
|
crate::num::codegen_checked_int_binop(fx, bin_op, lhs, rhs)
|
|
};
|
|
|
|
lval.write_cvalue(fx, res);
|
|
}
|
|
Rvalue::UnaryOp(un_op, ref operand) => {
|
|
let operand = codegen_operand(fx, operand);
|
|
let layout = operand.layout();
|
|
let val = operand.load_scalar(fx);
|
|
let res = match un_op {
|
|
UnOp::Not => match layout.ty.kind() {
|
|
ty::Bool => {
|
|
let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
|
|
CValue::by_val(fx.bcx.ins().bint(types::I8, res), layout)
|
|
}
|
|
ty::Uint(_) | ty::Int(_) => {
|
|
CValue::by_val(fx.bcx.ins().bnot(val), layout)
|
|
}
|
|
_ => unreachable!("un op Not for {:?}", layout.ty),
|
|
},
|
|
UnOp::Neg => match layout.ty.kind() {
|
|
ty::Int(IntTy::I128) => {
|
|
// FIXME remove this case once ineg.i128 works
|
|
let zero =
|
|
CValue::const_val(fx, layout, ty::ScalarInt::null(layout.size));
|
|
crate::num::codegen_int_binop(fx, BinOp::Sub, zero, operand)
|
|
}
|
|
ty::Int(_) => CValue::by_val(fx.bcx.ins().ineg(val), layout),
|
|
ty::Float(_) => CValue::by_val(fx.bcx.ins().fneg(val), layout),
|
|
_ => unreachable!("un op Neg for {:?}", layout.ty),
|
|
},
|
|
};
|
|
lval.write_cvalue(fx, res);
|
|
}
|
|
Rvalue::Cast(
|
|
CastKind::Pointer(PointerCast::ReifyFnPointer),
|
|
ref operand,
|
|
to_ty,
|
|
) => {
|
|
let from_ty = fx.monomorphize(operand.ty(&fx.mir.local_decls, fx.tcx));
|
|
let to_layout = fx.layout_of(fx.monomorphize(to_ty));
|
|
match *from_ty.kind() {
|
|
ty::FnDef(def_id, substs) => {
|
|
let func_ref = fx.get_function_ref(
|
|
Instance::resolve_for_fn_ptr(
|
|
fx.tcx,
|
|
ParamEnv::reveal_all(),
|
|
def_id,
|
|
substs,
|
|
)
|
|
.unwrap()
|
|
.polymorphize(fx.tcx),
|
|
);
|
|
let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
|
|
lval.write_cvalue(fx, CValue::by_val(func_addr, to_layout));
|
|
}
|
|
_ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", from_ty),
|
|
}
|
|
}
|
|
Rvalue::Cast(
|
|
CastKind::Pointer(PointerCast::UnsafeFnPointer),
|
|
ref operand,
|
|
to_ty,
|
|
)
|
|
| Rvalue::Cast(
|
|
CastKind::Pointer(PointerCast::MutToConstPointer),
|
|
ref operand,
|
|
to_ty,
|
|
)
|
|
| Rvalue::Cast(
|
|
CastKind::Pointer(PointerCast::ArrayToPointer),
|
|
ref operand,
|
|
to_ty,
|
|
) => {
|
|
let to_layout = fx.layout_of(fx.monomorphize(to_ty));
|
|
let operand = codegen_operand(fx, operand);
|
|
lval.write_cvalue(fx, operand.cast_pointer_to(to_layout));
|
|
}
|
|
Rvalue::Cast(CastKind::Misc, ref operand, to_ty) => {
|
|
let operand = codegen_operand(fx, operand);
|
|
let from_ty = operand.layout().ty;
|
|
let to_ty = fx.monomorphize(to_ty);
|
|
|
|
fn is_fat_ptr<'tcx>(
|
|
fx: &FunctionCx<'_, 'tcx, impl Module>,
|
|
ty: Ty<'tcx>,
|
|
) -> bool {
|
|
ty.builtin_deref(true)
|
|
.map(
|
|
|ty::TypeAndMut {
|
|
ty: pointee_ty,
|
|
mutbl: _,
|
|
}| {
|
|
has_ptr_meta(fx.tcx, pointee_ty)
|
|
},
|
|
)
|
|
.unwrap_or(false)
|
|
}
|
|
|
|
if is_fat_ptr(fx, from_ty) {
|
|
if is_fat_ptr(fx, to_ty) {
|
|
// fat-ptr -> fat-ptr
|
|
lval.write_cvalue(fx, operand.cast_pointer_to(dest_layout));
|
|
} else {
|
|
// fat-ptr -> thin-ptr
|
|
let (ptr, _extra) = operand.load_scalar_pair(fx);
|
|
lval.write_cvalue(fx, CValue::by_val(ptr, dest_layout))
|
|
}
|
|
} else if let ty::Adt(adt_def, _substs) = from_ty.kind() {
|
|
// enum -> discriminant value
|
|
assert!(adt_def.is_enum());
|
|
match to_ty.kind() {
|
|
ty::Uint(_) | ty::Int(_) => {}
|
|
_ => unreachable!("cast adt {} -> {}", from_ty, to_ty),
|
|
}
|
|
|
|
use rustc_target::abi::{Int, TagEncoding, Variants};
|
|
|
|
match operand.layout().variants {
|
|
Variants::Single { index } => {
|
|
let discr = operand
|
|
.layout()
|
|
.ty
|
|
.discriminant_for_variant(fx.tcx, index)
|
|
.unwrap();
|
|
let discr = if discr.ty.is_signed() {
|
|
fx.layout_of(discr.ty).size.sign_extend(discr.val)
|
|
} else {
|
|
discr.val
|
|
};
|
|
let discr = discr.into();
|
|
|
|
let discr = CValue::const_val(fx, fx.layout_of(to_ty), discr);
|
|
lval.write_cvalue(fx, discr);
|
|
}
|
|
Variants::Multiple {
|
|
ref tag,
|
|
tag_field,
|
|
tag_encoding: TagEncoding::Direct,
|
|
variants: _,
|
|
} => {
|
|
let cast_to = fx.clif_type(dest_layout.ty).unwrap();
|
|
|
|
// Read the tag/niche-encoded discriminant from memory.
|
|
let encoded_discr =
|
|
operand.value_field(fx, mir::Field::new(tag_field));
|
|
let encoded_discr = encoded_discr.load_scalar(fx);
|
|
|
|
// Decode the discriminant (specifically if it's niche-encoded).
|
|
let signed = match tag.value {
|
|
Int(_, signed) => signed,
|
|
_ => false,
|
|
};
|
|
let val = clif_intcast(fx, encoded_discr, cast_to, signed);
|
|
let val = CValue::by_val(val, dest_layout);
|
|
lval.write_cvalue(fx, val);
|
|
}
|
|
Variants::Multiple { .. } => unreachable!(),
|
|
}
|
|
} else {
|
|
let to_clif_ty = fx.clif_type(to_ty).unwrap();
|
|
let from = operand.load_scalar(fx);
|
|
|
|
let res = clif_int_or_float_cast(
|
|
fx,
|
|
from,
|
|
type_sign(from_ty),
|
|
to_clif_ty,
|
|
type_sign(to_ty),
|
|
);
|
|
lval.write_cvalue(fx, CValue::by_val(res, dest_layout));
|
|
}
|
|
}
|
|
Rvalue::Cast(
|
|
CastKind::Pointer(PointerCast::ClosureFnPointer(_)),
|
|
ref operand,
|
|
_to_ty,
|
|
) => {
|
|
let operand = codegen_operand(fx, operand);
|
|
match *operand.layout().ty.kind() {
|
|
ty::Closure(def_id, substs) => {
|
|
let instance = Instance::resolve_closure(
|
|
fx.tcx,
|
|
def_id,
|
|
substs,
|
|
ty::ClosureKind::FnOnce,
|
|
)
|
|
.polymorphize(fx.tcx);
|
|
let func_ref = fx.get_function_ref(instance);
|
|
let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
|
|
lval.write_cvalue(fx, CValue::by_val(func_addr, lval.layout()));
|
|
}
|
|
_ => bug!("{} cannot be cast to a fn ptr", operand.layout().ty),
|
|
}
|
|
}
|
|
Rvalue::Cast(CastKind::Pointer(PointerCast::Unsize), ref operand, _to_ty) => {
|
|
let operand = codegen_operand(fx, operand);
|
|
operand.unsize_value(fx, lval);
|
|
}
|
|
Rvalue::Discriminant(place) => {
|
|
let place = codegen_place(fx, place);
|
|
let value = place.to_cvalue(fx);
|
|
let discr =
|
|
crate::discriminant::codegen_get_discriminant(fx, value, dest_layout);
|
|
lval.write_cvalue(fx, discr);
|
|
}
|
|
Rvalue::Repeat(ref operand, times) => {
|
|
let operand = codegen_operand(fx, operand);
|
|
let times = fx
|
|
.monomorphize(times)
|
|
.eval(fx.tcx, ParamEnv::reveal_all())
|
|
.val
|
|
.try_to_bits(fx.tcx.data_layout.pointer_size)
|
|
.unwrap();
|
|
if fx.clif_type(operand.layout().ty) == Some(types::I8) {
|
|
let times = fx.bcx.ins().iconst(fx.pointer_type, times as i64);
|
|
// FIXME use emit_small_memset where possible
|
|
let addr = lval.to_ptr().get_addr(fx);
|
|
let val = operand.load_scalar(fx);
|
|
fx.bcx
|
|
.call_memset(fx.cx.module.target_config(), addr, val, times);
|
|
} else {
|
|
let loop_block = fx.bcx.create_block();
|
|
let loop_block2 = fx.bcx.create_block();
|
|
let done_block = fx.bcx.create_block();
|
|
let index = fx.bcx.append_block_param(loop_block, fx.pointer_type);
|
|
let zero = fx.bcx.ins().iconst(fx.pointer_type, 0);
|
|
fx.bcx.ins().jump(loop_block, &[zero]);
|
|
|
|
fx.bcx.switch_to_block(loop_block);
|
|
let done = fx.bcx.ins().icmp_imm(IntCC::Equal, index, times as i64);
|
|
fx.bcx.ins().brnz(done, done_block, &[]);
|
|
fx.bcx.ins().jump(loop_block2, &[]);
|
|
|
|
fx.bcx.switch_to_block(loop_block2);
|
|
let to = lval.place_index(fx, index);
|
|
to.write_cvalue(fx, operand);
|
|
let index = fx.bcx.ins().iadd_imm(index, 1);
|
|
fx.bcx.ins().jump(loop_block, &[index]);
|
|
|
|
fx.bcx.switch_to_block(done_block);
|
|
fx.bcx.ins().nop();
|
|
}
|
|
}
|
|
Rvalue::Len(place) => {
|
|
let place = codegen_place(fx, place);
|
|
let usize_layout = fx.layout_of(fx.tcx.types.usize);
|
|
let len = codegen_array_len(fx, place);
|
|
lval.write_cvalue(fx, CValue::by_val(len, usize_layout));
|
|
}
|
|
Rvalue::NullaryOp(NullOp::Box, content_ty) => {
|
|
let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
|
|
let content_ty = fx.monomorphize(content_ty);
|
|
let layout = fx.layout_of(content_ty);
|
|
let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64);
|
|
let llalign = fx
|
|
.bcx
|
|
.ins()
|
|
.iconst(usize_type, layout.align.abi.bytes() as i64);
|
|
let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
|
|
|
|
// Allocate space:
|
|
let def_id = match fx
|
|
.tcx
|
|
.lang_items()
|
|
.require(rustc_hir::LangItem::ExchangeMalloc)
|
|
{
|
|
Ok(id) => id,
|
|
Err(s) => {
|
|
fx.tcx
|
|
.sess
|
|
.fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
|
|
}
|
|
};
|
|
let instance = ty::Instance::mono(fx.tcx, def_id).polymorphize(fx.tcx);
|
|
let func_ref = fx.get_function_ref(instance);
|
|
let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
|
|
let ptr = fx.bcx.inst_results(call)[0];
|
|
lval.write_cvalue(fx, CValue::by_val(ptr, box_layout));
|
|
}
|
|
Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
|
|
assert!(lval
|
|
.layout()
|
|
.ty
|
|
.is_sized(fx.tcx.at(stmt.source_info.span), ParamEnv::reveal_all()));
|
|
let ty_size = fx.layout_of(fx.monomorphize(ty)).size.bytes();
|
|
let val =
|
|
CValue::const_val(fx, fx.layout_of(fx.tcx.types.usize), ty_size.into());
|
|
lval.write_cvalue(fx, val);
|
|
}
|
|
Rvalue::Aggregate(ref kind, ref operands) => match kind.as_ref() {
|
|
AggregateKind::Array(_ty) => {
|
|
for (i, operand) in operands.iter().enumerate() {
|
|
let operand = codegen_operand(fx, operand);
|
|
let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
|
|
let to = lval.place_index(fx, index);
|
|
to.write_cvalue(fx, operand);
|
|
}
|
|
}
|
|
_ => unreachable!("shouldn't exist at codegen {:?}", to_place_and_rval.1),
|
|
},
|
|
}
|
|
}
|
|
StatementKind::StorageLive(_)
|
|
| StatementKind::StorageDead(_)
|
|
| StatementKind::Nop
|
|
| StatementKind::FakeRead(..)
|
|
| StatementKind::Retag { .. }
|
|
| StatementKind::AscribeUserType(..) => {}
|
|
|
|
StatementKind::LlvmInlineAsm(asm) => {
|
|
use rustc_span::symbol::Symbol;
|
|
let LlvmInlineAsm {
|
|
asm,
|
|
outputs,
|
|
inputs,
|
|
} = &**asm;
|
|
let rustc_hir::LlvmInlineAsmInner {
|
|
asm: asm_code, // Name
|
|
outputs: output_names, // Vec<LlvmInlineAsmOutput>
|
|
inputs: input_names, // Vec<Name>
|
|
clobbers, // Vec<Name>
|
|
volatile, // bool
|
|
alignstack, // bool
|
|
dialect: _,
|
|
asm_str_style: _,
|
|
} = asm;
|
|
match asm_code.as_str().trim() {
|
|
"" => {
|
|
// Black box
|
|
}
|
|
"mov %rbx, %rsi\n cpuid\n xchg %rbx, %rsi" => {
|
|
assert_eq!(
|
|
input_names,
|
|
&[Symbol::intern("{eax}"), Symbol::intern("{ecx}")]
|
|
);
|
|
assert_eq!(output_names.len(), 4);
|
|
for (i, c) in (&["={eax}", "={esi}", "={ecx}", "={edx}"])
|
|
.iter()
|
|
.enumerate()
|
|
{
|
|
assert_eq!(&output_names[i].constraint.as_str(), c);
|
|
assert!(!output_names[i].is_rw);
|
|
assert!(!output_names[i].is_indirect);
|
|
}
|
|
|
|
assert_eq!(clobbers, &[]);
|
|
|
|
assert!(!volatile);
|
|
assert!(!alignstack);
|
|
|
|
assert_eq!(inputs.len(), 2);
|
|
let leaf = codegen_operand(fx, &inputs[0].1).load_scalar(fx); // %eax
|
|
let subleaf = codegen_operand(fx, &inputs[1].1).load_scalar(fx); // %ecx
|
|
|
|
let (eax, ebx, ecx, edx) =
|
|
crate::intrinsics::codegen_cpuid_call(fx, leaf, subleaf);
|
|
|
|
assert_eq!(outputs.len(), 4);
|
|
codegen_place(fx, outputs[0])
|
|
.write_cvalue(fx, CValue::by_val(eax, fx.layout_of(fx.tcx.types.u32)));
|
|
codegen_place(fx, outputs[1])
|
|
.write_cvalue(fx, CValue::by_val(ebx, fx.layout_of(fx.tcx.types.u32)));
|
|
codegen_place(fx, outputs[2])
|
|
.write_cvalue(fx, CValue::by_val(ecx, fx.layout_of(fx.tcx.types.u32)));
|
|
codegen_place(fx, outputs[3])
|
|
.write_cvalue(fx, CValue::by_val(edx, fx.layout_of(fx.tcx.types.u32)));
|
|
}
|
|
"xgetbv" => {
|
|
assert_eq!(input_names, &[Symbol::intern("{ecx}")]);
|
|
|
|
assert_eq!(output_names.len(), 2);
|
|
for (i, c) in (&["={eax}", "={edx}"]).iter().enumerate() {
|
|
assert_eq!(&output_names[i].constraint.as_str(), c);
|
|
assert!(!output_names[i].is_rw);
|
|
assert!(!output_names[i].is_indirect);
|
|
}
|
|
|
|
assert_eq!(clobbers, &[]);
|
|
|
|
assert!(!volatile);
|
|
assert!(!alignstack);
|
|
|
|
crate::trap::trap_unimplemented(fx, "_xgetbv arch intrinsic is not supported");
|
|
}
|
|
// ___chkstk, ___chkstk_ms and __alloca are only used on Windows
|
|
_ if fx
|
|
.tcx
|
|
.symbol_name(fx.instance)
|
|
.name
|
|
.starts_with("___chkstk") =>
|
|
{
|
|
crate::trap::trap_unimplemented(fx, "Stack probes are not supported");
|
|
}
|
|
_ if fx.tcx.symbol_name(fx.instance).name == "__alloca" => {
|
|
crate::trap::trap_unimplemented(fx, "Alloca is not supported");
|
|
}
|
|
// Used in sys::windows::abort_internal
|
|
"int $$0x29" => {
|
|
crate::trap::trap_unimplemented(fx, "Windows abort");
|
|
}
|
|
_ => fx
|
|
.tcx
|
|
.sess
|
|
.span_fatal(stmt.source_info.span, "Inline assembly is not supported"),
|
|
}
|
|
}
|
|
StatementKind::Coverage { .. } => fx.tcx.sess.fatal("-Zcoverage is unimplemented"),
|
|
}
|
|
}
|
|
|
|
fn codegen_array_len<'tcx>(
|
|
fx: &mut FunctionCx<'_, 'tcx, impl Module>,
|
|
place: CPlace<'tcx>,
|
|
) -> Value {
|
|
match *place.layout().ty.kind() {
|
|
ty::Array(_elem_ty, len) => {
|
|
let len = fx
|
|
.monomorphize(len)
|
|
.eval_usize(fx.tcx, ParamEnv::reveal_all()) as i64;
|
|
fx.bcx.ins().iconst(fx.pointer_type, len)
|
|
}
|
|
ty::Slice(_elem_ty) => place
|
|
.to_ptr_maybe_unsized()
|
|
.1
|
|
.expect("Length metadata for slice place"),
|
|
_ => bug!("Rvalue::Len({:?})", place),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn codegen_place<'tcx>(
|
|
fx: &mut FunctionCx<'_, 'tcx, impl Module>,
|
|
place: Place<'tcx>,
|
|
) -> CPlace<'tcx> {
|
|
let mut cplace = fx.get_local_place(place.local);
|
|
|
|
for elem in place.projection {
|
|
match elem {
|
|
PlaceElem::Deref => {
|
|
cplace = cplace.place_deref(fx);
|
|
}
|
|
PlaceElem::Field(field, _ty) => {
|
|
cplace = cplace.place_field(fx, field);
|
|
}
|
|
PlaceElem::Index(local) => {
|
|
let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
|
|
cplace = cplace.place_index(fx, index);
|
|
}
|
|
PlaceElem::ConstantIndex {
|
|
offset,
|
|
min_length: _,
|
|
from_end,
|
|
} => {
|
|
let offset: u64 = offset;
|
|
let index = if !from_end {
|
|
fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
|
|
} else {
|
|
let len = codegen_array_len(fx, cplace);
|
|
fx.bcx.ins().iadd_imm(len, -(offset as i64))
|
|
};
|
|
cplace = cplace.place_index(fx, index);
|
|
}
|
|
PlaceElem::Subslice { from, to, from_end } => {
|
|
// These indices are generated by slice patterns.
|
|
// slice[from:-to] in Python terms.
|
|
|
|
let from: u64 = from;
|
|
let to: u64 = to;
|
|
|
|
match cplace.layout().ty.kind() {
|
|
ty::Array(elem_ty, _len) => {
|
|
assert!(!from_end, "array subslices are never `from_end`");
|
|
let elem_layout = fx.layout_of(elem_ty);
|
|
let ptr = cplace.to_ptr();
|
|
cplace = CPlace::for_ptr(
|
|
ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * (from as i64)),
|
|
fx.layout_of(fx.tcx.mk_array(elem_ty, to - from)),
|
|
);
|
|
}
|
|
ty::Slice(elem_ty) => {
|
|
assert!(from_end, "slice subslices should be `from_end`");
|
|
let elem_layout = fx.layout_of(elem_ty);
|
|
let (ptr, len) = cplace.to_ptr_maybe_unsized();
|
|
let len = len.unwrap();
|
|
cplace = CPlace::for_ptr_with_extra(
|
|
ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * (from as i64)),
|
|
fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64)),
|
|
cplace.layout(),
|
|
);
|
|
}
|
|
_ => unreachable!(),
|
|
}
|
|
}
|
|
PlaceElem::Downcast(_adt_def, variant) => {
|
|
cplace = cplace.downcast_variant(fx, variant);
|
|
}
|
|
}
|
|
}
|
|
|
|
cplace
|
|
}
|
|
|
|
pub(crate) fn codegen_operand<'tcx>(
|
|
fx: &mut FunctionCx<'_, 'tcx, impl Module>,
|
|
operand: &Operand<'tcx>,
|
|
) -> CValue<'tcx> {
|
|
match operand {
|
|
Operand::Move(place) | Operand::Copy(place) => {
|
|
let cplace = codegen_place(fx, *place);
|
|
cplace.to_cvalue(fx)
|
|
}
|
|
Operand::Constant(const_) => crate::constant::codegen_constant(fx, const_),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn codegen_panic<'tcx>(
|
|
fx: &mut FunctionCx<'_, 'tcx, impl Module>,
|
|
msg_str: &str,
|
|
span: Span,
|
|
) {
|
|
let location = fx.get_caller_location(span).load_scalar(fx);
|
|
|
|
let msg_ptr = fx.anonymous_str("assert", msg_str);
|
|
let msg_len = fx
|
|
.bcx
|
|
.ins()
|
|
.iconst(fx.pointer_type, i64::try_from(msg_str.len()).unwrap());
|
|
let args = [msg_ptr, msg_len, location];
|
|
|
|
codegen_panic_inner(fx, rustc_hir::LangItem::Panic, &args, span);
|
|
}
|
|
|
|
pub(crate) fn codegen_panic_inner<'tcx>(
|
|
fx: &mut FunctionCx<'_, 'tcx, impl Module>,
|
|
lang_item: rustc_hir::LangItem,
|
|
args: &[Value],
|
|
span: Span,
|
|
) {
|
|
let def_id = fx
|
|
.tcx
|
|
.lang_items()
|
|
.require(lang_item)
|
|
.unwrap_or_else(|s| fx.tcx.sess.span_fatal(span, &s));
|
|
|
|
let instance = Instance::mono(fx.tcx, def_id).polymorphize(fx.tcx);
|
|
let symbol_name = fx.tcx.symbol_name(instance).name;
|
|
|
|
fx.lib_call(
|
|
&*symbol_name,
|
|
vec![
|
|
AbiParam::new(fx.pointer_type),
|
|
AbiParam::new(fx.pointer_type),
|
|
AbiParam::new(fx.pointer_type),
|
|
],
|
|
vec![],
|
|
args,
|
|
);
|
|
|
|
crate::trap::trap_unreachable(fx, "panic lang item returned");
|
|
}
|