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Merge commit 'dbee13661efa269cb4cd57bb4c6b99a19732b484' into sync_cg_clif-2020-12-27

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This commit is contained in:
bjorn3
2020-12-27 10:30:38 +01:00
parent 0f42d47bd5 dbee13661e
commit 52cf01c815
28 changed files with 490 additions and 275 deletions
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166
compiler/rustc_codegen_cranelift/src/driver/jit.rs
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@@ -1,16 +1,23 @@
//! The JIT driver uses [`cranelift_simplejit`] to JIT execute programs without writing any object
//! files.
use std::cell::RefCell;
use std::ffi::CString;
use std::os::raw::{c_char, c_int};
use rustc_codegen_ssa::CrateInfo;
use rustc_middle::mir::mono::MonoItem;
use cranelift_simplejit::{SimpleJITBuilder, SimpleJITModule};
use cranelift_jit::{JITBuilder, JITModule};
use crate::prelude::*;
use crate::{CodegenCx, CodegenMode};
pub(super) fn run_jit(tcx: TyCtxt<'_>) -> ! {
thread_local! {
pub static CURRENT_MODULE: RefCell<Option<JITModule>> = RefCell::new(None);
}
pub(super) fn run_jit(tcx: TyCtxt<'_>, codegen_mode: CodegenMode) -> ! {
if !tcx.sess.opts.output_types.should_codegen() {
tcx.sess.fatal("JIT mode doesn't work with `cargo check`.");
}
@@ -35,12 +42,13 @@ pub(super) fn run_jit(tcx: TyCtxt<'_>) -> ! {
let imported_symbols = load_imported_symbols_for_jit(tcx);
let mut jit_builder = SimpleJITBuilder::with_isa(
crate::build_isa(tcx.sess, false),
let mut jit_builder = JITBuilder::with_isa(
crate::build_isa(tcx.sess),
cranelift_module::default_libcall_names(),
);
jit_builder.hotswap(matches!(codegen_mode, CodegenMode::JitLazy));
jit_builder.symbols(imported_symbols);
let mut jit_module = SimpleJITModule::new(jit_builder);
let mut jit_module = JITModule::new(jit_builder);
assert_eq!(pointer_ty(tcx), jit_module.target_config().pointer_type());
let sig = Signature {
@@ -66,20 +74,42 @@ pub(super) fn run_jit(tcx: TyCtxt<'_>) -> ! {
.into_iter()
.collect::<Vec<(_, (_, _))>>();
let mut cx = crate::CodegenCx::new(tcx, jit_module, false);
let mut cx = crate::CodegenCx::new(tcx, jit_module, false, false);
super::time(tcx, "codegen mono items", || {
super::predefine_mono_items(&mut cx, &mono_items);
for (mono_item, (linkage, visibility)) in mono_items {
let linkage = crate::linkage::get_clif_linkage(mono_item, linkage, visibility);
match mono_item {
MonoItem::Fn(inst) => match codegen_mode {
CodegenMode::Aot => unreachable!(),
CodegenMode::Jit => {
cx.tcx.sess.time("codegen fn", || {
crate::base::codegen_fn(&mut cx, inst, linkage)
});
}
CodegenMode::JitLazy => codegen_shim(&mut cx, inst),
},
MonoItem::Static(def_id) => {
crate::constant::codegen_static(&mut cx.constants_cx, def_id);
}
MonoItem::GlobalAsm(hir_id) => {
let item = cx.tcx.hir().expect_item(hir_id);
tcx.sess
.span_fatal(item.span, "Global asm is not supported in JIT mode");
}
}
}
});
let (mut jit_module, global_asm, _debug, mut unwind_context) =
super::time(tcx, "codegen mono items", || {
super::predefine_mono_items(&mut cx, &mono_items);
for (mono_item, (linkage, visibility)) in mono_items {
let linkage = crate::linkage::get_clif_linkage(mono_item, linkage, visibility);
super::codegen_mono_item(&mut cx, mono_item, linkage);
}
tcx.sess.time("finalize CodegenCx", || cx.finalize())
});
tcx.sess.time("finalize CodegenCx", || cx.finalize());
jit_module.finalize_definitions();
if !global_asm.is_empty() {
tcx.sess.fatal("Global asm is not supported in JIT mode");
tcx.sess.fatal("Inline asm is not supported in JIT mode");
}
crate::main_shim::maybe_create_entry_wrapper(tcx, &mut jit_module, &mut unwind_context, true);
crate::allocator::codegen(tcx, &mut jit_module, &mut unwind_context);
@@ -91,7 +121,7 @@ pub(super) fn run_jit(tcx: TyCtxt<'_>) -> ! {
let finalized_main: *const u8 = jit_module.get_finalized_function(main_func_id);
println!("Rustc codegen cranelift will JIT run the executable, because --jit was passed");
println!("Rustc codegen cranelift will JIT run the executable, because -Cllvm-args=mode=jit was passed");
let f: extern "C" fn(c_int, *const *const c_char) -> c_int =
unsafe { ::std::mem::transmute(finalized_main) };
@@ -107,11 +137,50 @@ pub(super) fn run_jit(tcx: TyCtxt<'_>) -> ! {
// useful as some dynamic linkers use it as a marker to jump over.
argv.push(std::ptr::null());
CURRENT_MODULE
.with(|current_module| assert!(current_module.borrow_mut().replace(jit_module).is_none()));
let ret = f(args.len() as c_int, argv.as_ptr());
std::process::exit(ret);
}
#[no_mangle]
extern "C" fn __clif_jit_fn(instance_ptr: *const Instance<'static>) -> *const u8 {
rustc_middle::ty::tls::with(|tcx| {
// lift is used to ensure the correct lifetime for instance.
let instance = tcx.lift(unsafe { *instance_ptr }).unwrap();
CURRENT_MODULE.with(|jit_module| {
let mut jit_module = jit_module.borrow_mut();
let jit_module = jit_module.as_mut().unwrap();
let mut cx = crate::CodegenCx::new(tcx, jit_module, false, false);
let (name, sig) = crate::abi::get_function_name_and_sig(
tcx,
cx.module.isa().triple(),
instance,
true,
);
let func_id = cx
.module
.declare_function(&name, Linkage::Export, &sig)
.unwrap();
cx.module.prepare_for_function_redefine(func_id).unwrap();
tcx.sess.time("codegen fn", || {
crate::base::codegen_fn(&mut cx, instance, Linkage::Export)
});
let (jit_module, global_asm, _debug_context, unwind_context) = cx.finalize();
assert!(global_asm.is_empty());
jit_module.finalize_definitions();
std::mem::forget(unsafe { unwind_context.register_jit(&jit_module) });
jit_module.get_finalized_function(func_id)
})
})
}
fn load_imported_symbols_for_jit(tcx: TyCtxt<'_>) -> Vec<(String, *const u8)> {
use rustc_middle::middle::dependency_format::Linkage;
@@ -171,3 +240,68 @@ fn load_imported_symbols_for_jit(tcx: TyCtxt<'_>) -> Vec<(String, *const u8)> {
imported_symbols
}
pub(super) fn codegen_shim<'tcx>(cx: &mut CodegenCx<'tcx, impl Module>, inst: Instance<'tcx>) {
let tcx = cx.tcx;
let pointer_type = cx.module.target_config().pointer_type();
let (name, sig) =
crate::abi::get_function_name_and_sig(tcx, cx.module.isa().triple(), inst, true);
let func_id = cx
.module
.declare_function(&name, Linkage::Export, &sig)
.unwrap();
let instance_ptr = Box::into_raw(Box::new(inst));
let jit_fn = cx
.module
.declare_function(
"__clif_jit_fn",
Linkage::Import,
&Signature {
call_conv: cx.module.target_config().default_call_conv,
params: vec![AbiParam::new(pointer_type)],
returns: vec![AbiParam::new(pointer_type)],
},
)
.unwrap();
let mut trampoline = Function::with_name_signature(ExternalName::default(), sig.clone());
let mut builder_ctx = FunctionBuilderContext::new();
let mut trampoline_builder = FunctionBuilder::new(&mut trampoline, &mut builder_ctx);
let jit_fn = cx
.module
.declare_func_in_func(jit_fn, trampoline_builder.func);
let sig_ref = trampoline_builder.func.import_signature(sig);
let entry_block = trampoline_builder.create_block();
trampoline_builder.append_block_params_for_function_params(entry_block);
let fn_args = trampoline_builder
.func
.dfg
.block_params(entry_block)
.to_vec();
trampoline_builder.switch_to_block(entry_block);
let instance_ptr = trampoline_builder
.ins()
.iconst(pointer_type, instance_ptr as u64 as i64);
let jitted_fn = trampoline_builder.ins().call(jit_fn, &[instance_ptr]);
let jitted_fn = trampoline_builder.func.dfg.inst_results(jitted_fn)[0];
let call_inst = trampoline_builder
.ins()
.call_indirect(sig_ref, jitted_fn, &fn_args);
let ret_vals = trampoline_builder.func.dfg.inst_results(call_inst).to_vec();
trampoline_builder.ins().return_(&ret_vals);
cx.module
.define_function(
func_id,
&mut Context::for_function(trampoline),
&mut cranelift_codegen::binemit::NullTrapSink {},
)
.unwrap();
}