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|
//! The AOT driver uses [`cranelift_object`] to write object files suitable for linking into a
//! standalone executable.
use std::io::Write;
use std::path::PathBuf;
use std::process::{Command, Stdio};
use std::sync::Arc;
use rustc_ast::{InlineAsmOptions, InlineAsmTemplatePiece};
use rustc_hir::{InlineAsmOperand, ItemId};
use rustc_session::config::{OutputFilenames, OutputType};
use rustc_target::asm::InlineAsmArch;
use crate::prelude::*;
pub(crate) fn codegen_global_asm_item(tcx: TyCtxt<'_>, global_asm: &mut String, item_id: ItemId) {
let item = tcx.hir().item(item_id);
if let rustc_hir::ItemKind::GlobalAsm(asm) = item.kind {
let is_x86 =
matches!(tcx.sess.asm_arch.unwrap(), InlineAsmArch::X86 | InlineAsmArch::X86_64);
if is_x86 {
if !asm.options.contains(InlineAsmOptions::ATT_SYNTAX) {
global_asm.push_str("\n.intel_syntax noprefix\n");
} else {
global_asm.push_str("\n.att_syntax\n");
}
}
for piece in asm.template {
match *piece {
InlineAsmTemplatePiece::String(ref s) => global_asm.push_str(s),
InlineAsmTemplatePiece::Placeholder { operand_idx, modifier: _, span: op_sp } => {
match asm.operands[operand_idx].0 {
InlineAsmOperand::Const { ref anon_const } => {
let const_value =
tcx.const_eval_poly(anon_const.def_id.to_def_id()).unwrap_or_else(
|_| span_bug!(op_sp, "asm const cannot be resolved"),
);
let ty = tcx.typeck_body(anon_const.body).node_type(anon_const.hir_id);
let string = rustc_codegen_ssa::common::asm_const_to_str(
tcx,
op_sp,
const_value,
RevealAllLayoutCx(tcx).layout_of(ty),
);
global_asm.push_str(&string);
}
InlineAsmOperand::SymFn { anon_const } => {
if cfg!(not(feature = "inline_asm_sym")) {
tcx.sess.span_err(
item.span,
"asm! and global_asm! sym operands are not yet supported",
);
}
let ty = tcx.typeck_body(anon_const.body).node_type(anon_const.hir_id);
let instance = match ty.kind() {
&ty::FnDef(def_id, args) => Instance::new(def_id, args),
_ => span_bug!(op_sp, "asm sym is not a function"),
};
let symbol = tcx.symbol_name(instance);
// FIXME handle the case where the function was made private to the
// current codegen unit
global_asm.push_str(symbol.name);
}
InlineAsmOperand::SymStatic { path: _, def_id } => {
if cfg!(not(feature = "inline_asm_sym")) {
tcx.sess.span_err(
item.span,
"asm! and global_asm! sym operands are not yet supported",
);
}
let instance = Instance::mono(tcx, def_id).polymorphize(tcx);
let symbol = tcx.symbol_name(instance);
global_asm.push_str(symbol.name);
}
InlineAsmOperand::In { .. }
| InlineAsmOperand::Out { .. }
| InlineAsmOperand::InOut { .. }
| InlineAsmOperand::SplitInOut { .. } => {
span_bug!(op_sp, "invalid operand type for global_asm!")
}
}
}
}
}
global_asm.push('\n');
if is_x86 {
global_asm.push_str(".att_syntax\n\n");
}
} else {
bug!("Expected GlobalAsm found {:?}", item);
}
}
#[derive(Debug)]
pub(crate) struct GlobalAsmConfig {
assembler: PathBuf,
target: String,
pub(crate) output_filenames: Arc<OutputFilenames>,
}
impl GlobalAsmConfig {
pub(crate) fn new(tcx: TyCtxt<'_>) -> Self {
GlobalAsmConfig {
assembler: crate::toolchain::get_toolchain_binary(tcx.sess, "as"),
target: match &tcx.sess.opts.target_triple {
rustc_target::spec::TargetTriple::TargetTriple(triple) => triple.clone(),
rustc_target::spec::TargetTriple::TargetJson { path_for_rustdoc, .. } => {
path_for_rustdoc.to_str().unwrap().to_owned()
}
},
output_filenames: tcx.output_filenames(()).clone(),
}
}
}
pub(crate) fn compile_global_asm(
config: &GlobalAsmConfig,
cgu_name: &str,
global_asm: &str,
) -> Result<Option<PathBuf>, String> {
if global_asm.is_empty() {
return Ok(None);
}
// Remove all LLVM style comments
let mut global_asm = global_asm
.lines()
.map(|line| if let Some(index) = line.find("//") { &line[0..index] } else { line })
.collect::<Vec<_>>()
.join("\n");
global_asm.push('\n');
let global_asm_object_file = add_file_stem_postfix(
config.output_filenames.temp_path(OutputType::Object, Some(cgu_name)),
".asm",
);
// Assemble `global_asm`
if option_env!("CG_CLIF_FORCE_GNU_AS").is_some() {
let mut child = Command::new(&config.assembler)
.arg("-o")
.arg(&global_asm_object_file)
.stdin(Stdio::piped())
.spawn()
.expect("Failed to spawn `as`.");
child.stdin.take().unwrap().write_all(global_asm.as_bytes()).unwrap();
let status = child.wait().expect("Failed to wait for `as`.");
if !status.success() {
return Err(format!("Failed to assemble `{}`", global_asm));
}
} else {
let mut child = Command::new(std::env::current_exe().unwrap())
.arg("--target")
.arg(&config.target)
.arg("--crate-type")
.arg("staticlib")
.arg("--emit")
.arg("obj")
.arg("-o")
.arg(&global_asm_object_file)
.arg("-")
.arg("-Abad_asm_style")
.arg("-Zcodegen-backend=llvm")
.stdin(Stdio::piped())
.spawn()
.expect("Failed to spawn `as`.");
let mut stdin = child.stdin.take().unwrap();
stdin
.write_all(
br####"
#![feature(decl_macro, no_core, rustc_attrs)]
#![allow(internal_features)]
#![no_core]
#[rustc_builtin_macro]
#[rustc_macro_transparency = "semitransparent"]
macro global_asm() { /* compiler built-in */ }
global_asm!(r###"
"####,
)
.unwrap();
stdin.write_all(global_asm.as_bytes()).unwrap();
stdin
.write_all(
br####"
"###);
"####,
)
.unwrap();
std::mem::drop(stdin);
let status = child.wait().expect("Failed to wait for `as`.");
if !status.success() {
return Err(format!("Failed to assemble `{}`", global_asm));
}
}
Ok(Some(global_asm_object_file))
}
pub(crate) fn add_file_stem_postfix(mut path: PathBuf, postfix: &str) -> PathBuf {
let mut new_filename = path.file_stem().unwrap().to_owned();
new_filename.push(postfix);
if let Some(extension) = path.extension() {
new_filename.push(".");
new_filename.push(extension);
}
path.set_file_name(new_filename);
path
}
|
