blob: fae8a90b526ae2b61e5fd7100859f58bb07f495d [file] [log] [blame]
//! X86_64-bit Instruction Set Architecture.
pub use self::inst::{args, EmitInfo, EmitState, Inst};
use super::TargetIsa;
use crate::ir::{condcodes::IntCC, Function, Type};
#[cfg(feature = "unwind")]
use crate::isa::unwind::systemv;
use crate::isa::x64::{inst::regs::create_reg_env_systemv, settings as x64_settings};
use crate::isa::Builder as IsaBuilder;
use crate::machinst::{
compile, CompiledCode, CompiledCodeStencil, MachTextSectionBuilder, Reg, SigSet,
TextSectionBuilder, VCode,
};
use crate::result::{CodegenError, CodegenResult};
use crate::settings::{self as shared_settings, Flags};
use alloc::{boxed::Box, vec::Vec};
use core::fmt;
use regalloc2::MachineEnv;
use target_lexicon::Triple;
mod abi;
pub mod encoding;
mod inst;
mod lower;
mod settings;
/// An X64 backend.
pub(crate) struct X64Backend {
triple: Triple,
flags: Flags,
x64_flags: x64_settings::Flags,
reg_env: MachineEnv,
}
impl X64Backend {
/// Create a new X64 backend with the given (shared) flags.
fn new_with_flags(triple: Triple, flags: Flags, x64_flags: x64_settings::Flags) -> Self {
let reg_env = create_reg_env_systemv(&flags);
Self {
triple,
flags,
x64_flags,
reg_env,
}
}
fn compile_vcode(
&self,
func: &Function,
) -> CodegenResult<(VCode<inst::Inst>, regalloc2::Output)> {
// This performs lowering to VCode, register-allocates the code, computes
// block layout and finalizes branches. The result is ready for binary emission.
let emit_info = EmitInfo::new(self.flags.clone(), self.x64_flags.clone());
let sigs = SigSet::new::<abi::X64ABIMachineSpec>(func, &self.flags)?;
let abi = abi::X64Callee::new(&func, self, &self.x64_flags, &sigs)?;
compile::compile::<Self>(&func, self, abi, emit_info, sigs)
}
}
impl TargetIsa for X64Backend {
fn compile_function(
&self,
func: &Function,
want_disasm: bool,
) -> CodegenResult<CompiledCodeStencil> {
let (vcode, regalloc_result) = self.compile_vcode(func)?;
let emit_result = vcode.emit(
&regalloc_result,
want_disasm,
self.flags.machine_code_cfg_info(),
);
let frame_size = emit_result.frame_size;
let value_labels_ranges = emit_result.value_labels_ranges;
let buffer = emit_result.buffer.finish();
let sized_stackslot_offsets = emit_result.sized_stackslot_offsets;
let dynamic_stackslot_offsets = emit_result.dynamic_stackslot_offsets;
if let Some(disasm) = emit_result.disasm.as_ref() {
log::trace!("disassembly:\n{}", disasm);
}
Ok(CompiledCodeStencil {
buffer,
frame_size,
disasm: emit_result.disasm,
value_labels_ranges,
sized_stackslot_offsets,
dynamic_stackslot_offsets,
bb_starts: emit_result.bb_offsets,
bb_edges: emit_result.bb_edges,
alignment: emit_result.alignment,
})
}
fn flags(&self) -> &Flags {
&self.flags
}
fn machine_env(&self) -> &MachineEnv {
&self.reg_env
}
fn isa_flags(&self) -> Vec<shared_settings::Value> {
self.x64_flags.iter().collect()
}
fn dynamic_vector_bytes(&self, _dyn_ty: Type) -> u32 {
16
}
fn name(&self) -> &'static str {
"x64"
}
fn triple(&self) -> &Triple {
&self.triple
}
fn unsigned_add_overflow_condition(&self) -> IntCC {
// Unsigned `<`; this corresponds to the carry flag set on x86, which
// indicates an add has overflowed.
IntCC::UnsignedLessThan
}
#[cfg(feature = "unwind")]
fn emit_unwind_info(
&self,
result: &CompiledCode,
kind: crate::machinst::UnwindInfoKind,
) -> CodegenResult<Option<crate::isa::unwind::UnwindInfo>> {
use crate::isa::unwind::UnwindInfo;
use crate::machinst::UnwindInfoKind;
Ok(match kind {
UnwindInfoKind::SystemV => {
let mapper = self::inst::unwind::systemv::RegisterMapper;
Some(UnwindInfo::SystemV(
crate::isa::unwind::systemv::create_unwind_info_from_insts(
&result.buffer.unwind_info[..],
result.buffer.data().len(),
&mapper,
)?,
))
}
UnwindInfoKind::Windows => Some(UnwindInfo::WindowsX64(
crate::isa::unwind::winx64::create_unwind_info_from_insts::<
self::inst::unwind::winx64::RegisterMapper,
>(&result.buffer.unwind_info[..])?,
)),
_ => None,
})
}
#[cfg(feature = "unwind")]
fn create_systemv_cie(&self) -> Option<gimli::write::CommonInformationEntry> {
Some(inst::unwind::systemv::create_cie())
}
#[cfg(feature = "unwind")]
fn map_regalloc_reg_to_dwarf(&self, reg: Reg) -> Result<u16, systemv::RegisterMappingError> {
inst::unwind::systemv::map_reg(reg).map(|reg| reg.0)
}
fn text_section_builder(&self, num_funcs: usize) -> Box<dyn TextSectionBuilder> {
Box::new(MachTextSectionBuilder::<inst::Inst>::new(num_funcs))
}
/// Align functions on x86 to 16 bytes, ensuring that rip-relative loads to SSE registers are
/// always from aligned memory.
fn function_alignment(&self) -> u32 {
16
}
}
impl fmt::Display for X64Backend {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("MachBackend")
.field("name", &self.name())
.field("triple", &self.triple())
.field("flags", &format!("{}", self.flags()))
.finish()
}
}
/// Create a new `isa::Builder`.
pub(crate) fn isa_builder(triple: Triple) -> IsaBuilder {
IsaBuilder {
triple,
setup: x64_settings::builder(),
constructor: isa_constructor,
}
}
fn isa_constructor(
triple: Triple,
shared_flags: Flags,
builder: shared_settings::Builder,
) -> CodegenResult<Box<dyn TargetIsa>> {
let isa_flags = x64_settings::Flags::new(&shared_flags, builder);
// Check for compatibility between flags and ISA level
// requested. In particular, SIMD support requires SSE4.2.
if shared_flags.enable_simd() {
if !isa_flags.has_sse3()
|| !isa_flags.has_ssse3()
|| !isa_flags.has_sse41()
|| !isa_flags.has_sse42()
{
return Err(CodegenError::Unsupported(
"SIMD support requires SSE3, SSSE3, SSE4.1, and SSE4.2 on x86_64.".into(),
));
}
}
let backend = X64Backend::new_with_flags(triple, shared_flags, isa_flags);
Ok(Box::new(backend))
}
#[cfg(test)]
mod test {
use super::*;
use crate::cursor::{Cursor, FuncCursor};
use crate::ir::{types::*, RelSourceLoc, SourceLoc, UserFuncName, ValueLabel, ValueLabelStart};
use crate::ir::{AbiParam, Function, InstBuilder, JumpTableData, Signature};
use crate::isa::CallConv;
use crate::settings;
use crate::settings::Configurable;
use core::str::FromStr;
use cranelift_entity::EntityRef;
use target_lexicon::Triple;
/// We have to test cold blocks by observing final machine code,
/// rather than VCode, because the VCode orders blocks in lowering
/// order, not emission order. (The exact difference between the
/// two is that cold blocks are sunk in the latter.) We might as
/// well do the test here, where we have a backend to use.
#[test]
fn test_cold_blocks() {
let name = UserFuncName::testcase("test0");
let mut sig = Signature::new(CallConv::SystemV);
sig.params.push(AbiParam::new(I32));
sig.returns.push(AbiParam::new(I32));
let mut func = Function::with_name_signature(name, sig);
// Add debug info: this tests the debug machinery wrt cold
// blocks as well.
func.dfg.collect_debug_info();
let bb0 = func.dfg.make_block();
let arg0 = func.dfg.append_block_param(bb0, I32);
let bb1 = func.dfg.make_block();
let bb2 = func.dfg.make_block();
let bb3 = func.dfg.make_block();
let bb1_param = func.dfg.append_block_param(bb1, I32);
let bb3_param = func.dfg.append_block_param(bb3, I32);
let mut pos = FuncCursor::new(&mut func);
pos.insert_block(bb0);
pos.set_srcloc(SourceLoc::new(1));
let v0 = pos.ins().iconst(I32, 0x1234);
pos.set_srcloc(SourceLoc::new(2));
let v1 = pos.ins().iadd(arg0, v0);
pos.ins().brnz(v1, bb1, &[v1]);
pos.ins().jump(bb2, &[]);
pos.insert_block(bb1);
pos.set_srcloc(SourceLoc::new(3));
let v2 = pos.ins().isub(v1, v0);
pos.set_srcloc(SourceLoc::new(4));
let v3 = pos.ins().iadd(v2, bb1_param);
pos.ins().brnz(v1, bb2, &[]);
pos.ins().jump(bb3, &[v3]);
pos.func.layout.set_cold(bb2);
pos.insert_block(bb2);
pos.set_srcloc(SourceLoc::new(5));
let v4 = pos.ins().iadd(v1, v0);
pos.ins().brnz(v4, bb2, &[]);
pos.ins().jump(bb1, &[v4]);
pos.insert_block(bb3);
pos.set_srcloc(SourceLoc::new(6));
pos.ins().return_(&[bb3_param]);
// Create some debug info. Make one label that follows all the
// values around. Note that this is usually done via an API on
// the FunctionBuilder, but that's in cranelift_frontend
// (i.e., a higher level of the crate DAG) so we have to build
// it manually here.
pos.func.dfg.values_labels.as_mut().unwrap().insert(
v0,
crate::ir::ValueLabelAssignments::Starts(vec![ValueLabelStart {
from: RelSourceLoc::new(1),
label: ValueLabel::new(1),
}]),
);
pos.func.dfg.values_labels.as_mut().unwrap().insert(
v1,
crate::ir::ValueLabelAssignments::Starts(vec![ValueLabelStart {
from: RelSourceLoc::new(2),
label: ValueLabel::new(1),
}]),
);
pos.func.dfg.values_labels.as_mut().unwrap().insert(
v2,
crate::ir::ValueLabelAssignments::Starts(vec![ValueLabelStart {
from: RelSourceLoc::new(3),
label: ValueLabel::new(1),
}]),
);
pos.func.dfg.values_labels.as_mut().unwrap().insert(
v3,
crate::ir::ValueLabelAssignments::Starts(vec![ValueLabelStart {
from: RelSourceLoc::new(4),
label: ValueLabel::new(1),
}]),
);
pos.func.dfg.values_labels.as_mut().unwrap().insert(
v4,
crate::ir::ValueLabelAssignments::Starts(vec![ValueLabelStart {
from: RelSourceLoc::new(5),
label: ValueLabel::new(1),
}]),
);
let mut shared_flags_builder = settings::builder();
shared_flags_builder.set("opt_level", "none").unwrap();
shared_flags_builder.set("enable_verifier", "true").unwrap();
let shared_flags = settings::Flags::new(shared_flags_builder);
let isa_flags = x64_settings::Flags::new(&shared_flags, x64_settings::builder());
let backend = X64Backend::new_with_flags(
Triple::from_str("x86_64").unwrap(),
shared_flags,
isa_flags,
);
let result = backend
.compile_function(&mut func, /* want_disasm = */ false)
.unwrap();
let code = result.buffer.data();
// To update this comment, write the golden bytes to a file, and run the following
// command on it:
// > objdump -b binary -D <file> -m i386:x86-64 -M intel
//
// 0: 55 push rbp
// 1: 48 89 e5 mov rbp,rsp
// 4: 48 89 fe mov rsi,rdi
// 7: 81 c6 34 12 00 00 add esi,0x1234
// d: 85 f6 test esi,esi
// f: 0f 84 1c 00 00 00 je 0x31
// 15: 49 89 f0 mov r8,rsi
// 18: 48 89 f0 mov rax,rsi
// 1b: 81 e8 34 12 00 00 sub eax,0x1234
// 21: 44 01 c0 add eax,r8d
// 24: 85 f6 test esi,esi
// 26: 0f 85 05 00 00 00 jne 0x31
// 2c: 48 89 ec mov rsp,rbp
// 2f: 5d pop rbp
// 30: c3 ret
// 31: 49 89 f0 mov r8,rsi
// 34: 41 81 c0 34 12 00 00 add r8d,0x1234
// 3b: 45 85 c0 test r8d,r8d
// 3e: 0f 85 ed ff ff ff jne 0x31
// 44: e9 cf ff ff ff jmp 0x18
let golden = vec![
85, 72, 137, 229, 72, 137, 254, 129, 198, 52, 18, 0, 0, 133, 246, 15, 132, 28, 0, 0, 0,
73, 137, 240, 72, 137, 240, 129, 232, 52, 18, 0, 0, 68, 1, 192, 133, 246, 15, 133, 5,
0, 0, 0, 72, 137, 236, 93, 195, 73, 137, 240, 65, 129, 192, 52, 18, 0, 0, 69, 133, 192,
15, 133, 237, 255, 255, 255, 233, 207, 255, 255, 255,
];
assert_eq!(code, &golden[..]);
}
// Check that feature tests for SIMD work correctly.
#[test]
fn simd_required_features() {
let mut shared_flags_builder = settings::builder();
shared_flags_builder.set("enable_simd", "true").unwrap();
let shared_flags = settings::Flags::new(shared_flags_builder);
let mut isa_builder = crate::isa::lookup_by_name("x86_64").unwrap();
isa_builder.set("has_sse3", "false").unwrap();
isa_builder.set("has_ssse3", "false").unwrap();
isa_builder.set("has_sse41", "false").unwrap();
isa_builder.set("has_sse42", "false").unwrap();
assert!(matches!(
isa_builder.finish(shared_flags),
Err(CodegenError::Unsupported(_)),
));
}
// Check that br_table lowers properly. We can't test this with an
// ordinary compile-test because the br_table pseudoinstruction
// expands during emission.
#[test]
fn br_table() {
let name = UserFuncName::testcase("test0");
let mut sig = Signature::new(CallConv::SystemV);
sig.params.push(AbiParam::new(I32));
sig.returns.push(AbiParam::new(I32));
let mut func = Function::with_name_signature(name, sig);
let bb0 = func.dfg.make_block();
let arg0 = func.dfg.append_block_param(bb0, I32);
let bb1 = func.dfg.make_block();
let bb2 = func.dfg.make_block();
let bb3 = func.dfg.make_block();
let mut pos = FuncCursor::new(&mut func);
pos.insert_block(bb0);
let mut jt_data = JumpTableData::new();
jt_data.push_entry(bb1);
jt_data.push_entry(bb2);
let jt = pos.func.create_jump_table(jt_data);
pos.ins().br_table(arg0, bb3, jt);
pos.insert_block(bb1);
let v1 = pos.ins().iconst(I32, 1);
pos.ins().return_(&[v1]);
pos.insert_block(bb2);
let v2 = pos.ins().iconst(I32, 2);
pos.ins().return_(&[v2]);
pos.insert_block(bb3);
let v3 = pos.ins().iconst(I32, 3);
pos.ins().return_(&[v3]);
let mut shared_flags_builder = settings::builder();
shared_flags_builder.set("opt_level", "none").unwrap();
shared_flags_builder.set("enable_verifier", "true").unwrap();
let shared_flags = settings::Flags::new(shared_flags_builder);
let isa_flags = x64_settings::Flags::new(&shared_flags, x64_settings::builder());
let backend = X64Backend::new_with_flags(
Triple::from_str("x86_64").unwrap(),
shared_flags,
isa_flags,
);
let result = backend
.compile_function(&mut func, /* want_disasm = */ false)
.unwrap();
let code = result.buffer.data();
// To update this comment, write the golden bytes to a file, and run the following
// command on it:
// > objdump -b binary -D <file> -m i386:x86-64 -M intel
//
// 0: 55 push rbp
// 1: 48 89 e5 mov rbp,rsp
// 4: 83 ff 02 cmp edi,0x2
// 7: 0f 83 27 00 00 00 jae 0x34
// d: 44 8b d7 mov r10d,edi
// 10: 41 b9 00 00 00 00 mov r9d,0x0
// 16: 4d 0f 43 d1 cmovae r10,r9
// 1a: 4c 8d 0d 0b 00 00 00 lea r9,[rip+0xb] # 0x2c
// 21: 4f 63 54 91 00 movsxd r10,DWORD PTR [r9+r10*4+0x0]
// 26: 4d 01 d1 add r9,r10
// 29: 41 ff e1 jmp r9
// 2c: 12 00 adc al,BYTE PTR [rax]
// 2e: 00 00 add BYTE PTR [rax],al
// 30: 1c 00 sbb al,0x0
// 32: 00 00 add BYTE PTR [rax],al
// 34: b8 03 00 00 00 mov eax,0x3
// 39: 48 89 ec mov rsp,rbp
// 3c: 5d pop rbp
// 3d: c3 ret
// 3e: b8 01 00 00 00 mov eax,0x1
// 43: 48 89 ec mov rsp,rbp
// 46: 5d pop rbp
// 47: c3 ret
// 48: b8 02 00 00 00 mov eax,0x2
// 4d: 48 89 ec mov rsp,rbp
// 50: 5d pop rbp
// 51: c3 ret
let golden = vec![
85, 72, 137, 229, 131, 255, 2, 15, 131, 39, 0, 0, 0, 68, 139, 215, 65, 185, 0, 0, 0, 0,
77, 15, 67, 209, 76, 141, 13, 11, 0, 0, 0, 79, 99, 84, 145, 0, 77, 1, 209, 65, 255,
225, 18, 0, 0, 0, 28, 0, 0, 0, 184, 3, 0, 0, 0, 72, 137, 236, 93, 195, 184, 1, 0, 0, 0,
72, 137, 236, 93, 195, 184, 2, 0, 0, 0, 72, 137, 236, 93, 195,
];
assert_eq!(code, &golden[..]);
}
}