diff options
Diffstat (limited to 'compiler/rustc_codegen_cranelift/src/common.rs')
| -rw-r--r-- | compiler/rustc_codegen_cranelift/src/common.rs | 518 |
1 files changed, 518 insertions, 0 deletions
diff --git a/compiler/rustc_codegen_cranelift/src/common.rs b/compiler/rustc_codegen_cranelift/src/common.rs new file mode 100644 index 00000000000..21d0cd2d30f --- /dev/null +++ b/compiler/rustc_codegen_cranelift/src/common.rs @@ -0,0 +1,518 @@ +use cranelift_codegen::isa::TargetFrontendConfig; +use cranelift_frontend::{FunctionBuilder, FunctionBuilderContext}; +use rustc_index::IndexVec; +use rustc_middle::ty::layout::{ + self, FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers, +}; +use rustc_middle::ty::TypeFoldable; +use rustc_span::source_map::Spanned; +use rustc_target::abi::call::FnAbi; +use rustc_target::abi::{Float, Integer, Primitive}; +use rustc_target::spec::{HasTargetSpec, Target}; + +use crate::constant::ConstantCx; +use crate::debuginfo::FunctionDebugContext; +use crate::prelude::*; + +pub(crate) fn pointer_ty(tcx: TyCtxt<'_>) -> types::Type { + match tcx.data_layout.pointer_size.bits() { + 16 => types::I16, + 32 => types::I32, + 64 => types::I64, + bits => bug!("ptr_sized_integer: unknown pointer bit size {}", bits), + } +} + +pub(crate) fn scalar_to_clif_type(tcx: TyCtxt<'_>, scalar: Scalar) -> Type { + match scalar.primitive() { + Primitive::Int(int, _sign) => match int { + Integer::I8 => types::I8, + Integer::I16 => types::I16, + Integer::I32 => types::I32, + Integer::I64 => types::I64, + Integer::I128 => types::I128, + }, + Primitive::Float(float) => match float { + Float::F16 => unimplemented!("f16_f128"), + Float::F32 => types::F32, + Float::F64 => types::F64, + Float::F128 => unimplemented!("f16_f128"), + }, + // FIXME(erikdesjardins): handle non-default addrspace ptr sizes + Primitive::Pointer(_) => pointer_ty(tcx), + } +} + +fn clif_type_from_ty<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Option<types::Type> { + Some(match ty.kind() { + ty::Bool => types::I8, + ty::Uint(size) => match size { + UintTy::U8 => types::I8, + UintTy::U16 => types::I16, + UintTy::U32 => types::I32, + UintTy::U64 => types::I64, + UintTy::U128 => types::I128, + UintTy::Usize => pointer_ty(tcx), + }, + ty::Int(size) => match size { + IntTy::I8 => types::I8, + IntTy::I16 => types::I16, + IntTy::I32 => types::I32, + IntTy::I64 => types::I64, + IntTy::I128 => types::I128, + IntTy::Isize => pointer_ty(tcx), + }, + ty::Char => types::I32, + ty::Float(size) => match size { + FloatTy::F16 => unimplemented!("f16_f128"), + FloatTy::F32 => types::F32, + FloatTy::F64 => types::F64, + FloatTy::F128 => unimplemented!("f16_f128"), + }, + ty::FnPtr(_) => pointer_ty(tcx), + ty::RawPtr(pointee_ty, _) | ty::Ref(_, pointee_ty, _) => { + if has_ptr_meta(tcx, *pointee_ty) { + return None; + } else { + pointer_ty(tcx) + } + } + ty::Param(_) => bug!("ty param {:?}", ty), + _ => return None, + }) +} + +fn clif_pair_type_from_ty<'tcx>( + tcx: TyCtxt<'tcx>, + ty: Ty<'tcx>, +) -> Option<(types::Type, types::Type)> { + Some(match ty.kind() { + ty::Tuple(types) if types.len() == 2 => { + (clif_type_from_ty(tcx, types[0])?, clif_type_from_ty(tcx, types[1])?) + } + ty::RawPtr(pointee_ty, _) | ty::Ref(_, pointee_ty, _) => { + if has_ptr_meta(tcx, *pointee_ty) { + (pointer_ty(tcx), pointer_ty(tcx)) + } else { + return None; + } + } + _ => return None, + }) +} + +/// Is a pointer to this type a fat ptr? +pub(crate) fn has_ptr_meta<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> bool { + if ty.is_sized(tcx, ParamEnv::reveal_all()) { + return false; + } + + let tail = tcx.struct_tail_erasing_lifetimes(ty, ParamEnv::reveal_all()); + match tail.kind() { + ty::Foreign(..) => false, + ty::Str | ty::Slice(..) | ty::Dynamic(..) => true, + _ => bug!("unexpected unsized tail: {:?}", tail), + } +} + +pub(crate) fn codegen_icmp_imm( + fx: &mut FunctionCx<'_, '_, '_>, + intcc: IntCC, + lhs: Value, + rhs: i128, +) -> Value { + let lhs_ty = fx.bcx.func.dfg.value_type(lhs); + if lhs_ty == types::I128 { + // FIXME legalize `icmp_imm.i128` in Cranelift + + let (lhs_lsb, lhs_msb) = fx.bcx.ins().isplit(lhs); + let (rhs_lsb, rhs_msb) = (rhs as u128 as u64 as i64, (rhs as u128 >> 64) as u64 as i64); + + match intcc { + IntCC::Equal => { + let lsb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_lsb, rhs_lsb); + let msb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_msb, rhs_msb); + fx.bcx.ins().band(lsb_eq, msb_eq) + } + IntCC::NotEqual => { + let lsb_ne = fx.bcx.ins().icmp_imm(IntCC::NotEqual, lhs_lsb, rhs_lsb); + let msb_ne = fx.bcx.ins().icmp_imm(IntCC::NotEqual, lhs_msb, rhs_msb); + fx.bcx.ins().bor(lsb_ne, msb_ne) + } + _ => { + // if msb_eq { + // lsb_cc + // } else { + // msb_cc + // } + + let msb_eq = fx.bcx.ins().icmp_imm(IntCC::Equal, lhs_msb, rhs_msb); + let lsb_cc = fx.bcx.ins().icmp_imm(intcc, lhs_lsb, rhs_lsb); + let msb_cc = fx.bcx.ins().icmp_imm(intcc, lhs_msb, rhs_msb); + + fx.bcx.ins().select(msb_eq, lsb_cc, msb_cc) + } + } + } else { + let rhs = rhs as i64; // Truncates on purpose in case rhs is actually an unsigned value + fx.bcx.ins().icmp_imm(intcc, lhs, rhs) + } +} + +pub(crate) fn codegen_bitcast(fx: &mut FunctionCx<'_, '_, '_>, dst_ty: Type, val: Value) -> Value { + let mut flags = MemFlags::new(); + flags.set_endianness(match fx.tcx.data_layout.endian { + rustc_target::abi::Endian::Big => cranelift_codegen::ir::Endianness::Big, + rustc_target::abi::Endian::Little => cranelift_codegen::ir::Endianness::Little, + }); + fx.bcx.ins().bitcast(dst_ty, flags, val) +} + +pub(crate) fn type_zero_value(bcx: &mut FunctionBuilder<'_>, ty: Type) -> Value { + if ty == types::I128 { + let zero = bcx.ins().iconst(types::I64, 0); + bcx.ins().iconcat(zero, zero) + } else { + bcx.ins().iconst(ty, 0) + } +} + +pub(crate) fn type_min_max_value( + bcx: &mut FunctionBuilder<'_>, + ty: Type, + signed: bool, +) -> (Value, Value) { + assert!(ty.is_int()); + + if ty == types::I128 { + if signed { + let min = i128::MIN as u128; + let min_lsb = bcx.ins().iconst(types::I64, min as u64 as i64); + let min_msb = bcx.ins().iconst(types::I64, (min >> 64) as u64 as i64); + let min = bcx.ins().iconcat(min_lsb, min_msb); + + let max = i128::MAX as u128; + let max_lsb = bcx.ins().iconst(types::I64, max as u64 as i64); + let max_msb = bcx.ins().iconst(types::I64, (max >> 64) as u64 as i64); + let max = bcx.ins().iconcat(max_lsb, max_msb); + + return (min, max); + } else { + let min_half = bcx.ins().iconst(types::I64, 0); + let min = bcx.ins().iconcat(min_half, min_half); + + let max_half = bcx.ins().iconst(types::I64, u64::MAX as i64); + let max = bcx.ins().iconcat(max_half, max_half); + + return (min, max); + } + } + + let min = match (ty, signed) { + (types::I8, false) | (types::I16, false) | (types::I32, false) | (types::I64, false) => { + 0i64 + } + (types::I8, true) => i64::from(i8::MIN as u8), + (types::I16, true) => i64::from(i16::MIN as u16), + (types::I32, true) => i64::from(i32::MIN as u32), + (types::I64, true) => i64::MIN, + _ => unreachable!(), + }; + + let max = match (ty, signed) { + (types::I8, false) => i64::from(u8::MAX), + (types::I16, false) => i64::from(u16::MAX), + (types::I32, false) => i64::from(u32::MAX), + (types::I64, false) => u64::MAX as i64, + (types::I8, true) => i64::from(i8::MAX as u8), + (types::I16, true) => i64::from(i16::MAX as u16), + (types::I32, true) => i64::from(i32::MAX as u32), + (types::I64, true) => i64::MAX, + _ => unreachable!(), + }; + + let (min, max) = (bcx.ins().iconst(ty, min), bcx.ins().iconst(ty, max)); + + (min, max) +} + +pub(crate) fn type_sign(ty: Ty<'_>) -> bool { + match ty.kind() { + ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..) | ty::Char | ty::Uint(..) | ty::Bool => false, + ty::Int(..) => true, + ty::Float(..) => false, // `signed` is unused for floats + _ => panic!("{}", ty), + } +} + +pub(crate) fn create_wrapper_function( + module: &mut dyn Module, + unwind_context: &mut UnwindContext, + sig: Signature, + wrapper_name: &str, + callee_name: &str, +) { + let wrapper_func_id = module.declare_function(wrapper_name, Linkage::Export, &sig).unwrap(); + let callee_func_id = module.declare_function(callee_name, Linkage::Import, &sig).unwrap(); + + let mut ctx = Context::new(); + ctx.func.signature = sig; + { + let mut func_ctx = FunctionBuilderContext::new(); + let mut bcx = FunctionBuilder::new(&mut ctx.func, &mut func_ctx); + + let block = bcx.create_block(); + bcx.switch_to_block(block); + let func = &mut bcx.func.stencil; + let args = func + .signature + .params + .iter() + .map(|param| func.dfg.append_block_param(block, param.value_type)) + .collect::<Vec<Value>>(); + + let callee_func_ref = module.declare_func_in_func(callee_func_id, &mut bcx.func); + let call_inst = bcx.ins().call(callee_func_ref, &args); + let results = bcx.inst_results(call_inst).to_vec(); // Clone to prevent borrow error + + bcx.ins().return_(&results); + bcx.seal_all_blocks(); + bcx.finalize(); + } + module.define_function(wrapper_func_id, &mut ctx).unwrap(); + unwind_context.add_function(wrapper_func_id, &ctx, module.isa()); +} + +pub(crate) struct FunctionCx<'m, 'clif, 'tcx: 'm> { + pub(crate) cx: &'clif mut crate::CodegenCx, + pub(crate) module: &'m mut dyn Module, + pub(crate) tcx: TyCtxt<'tcx>, + pub(crate) target_config: TargetFrontendConfig, // Cached from module + pub(crate) pointer_type: Type, // Cached from module + pub(crate) constants_cx: ConstantCx, + pub(crate) func_debug_cx: Option<FunctionDebugContext>, + + pub(crate) instance: Instance<'tcx>, + pub(crate) symbol_name: String, + pub(crate) mir: &'tcx Body<'tcx>, + pub(crate) fn_abi: &'tcx FnAbi<'tcx, Ty<'tcx>>, + + pub(crate) bcx: FunctionBuilder<'clif>, + pub(crate) block_map: IndexVec<BasicBlock, Block>, + pub(crate) local_map: IndexVec<Local, CPlace<'tcx>>, + + /// When `#[track_caller]` is used, the implicit caller location is stored in this variable. + pub(crate) caller_location: Option<CValue<'tcx>>, + + pub(crate) clif_comments: crate::pretty_clif::CommentWriter, + + /// This should only be accessed by `CPlace::new_var`. + pub(crate) next_ssa_var: u32, +} + +impl<'tcx> LayoutOfHelpers<'tcx> for FunctionCx<'_, '_, 'tcx> { + type LayoutOfResult = TyAndLayout<'tcx>; + + #[inline] + fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! { + RevealAllLayoutCx(self.tcx).handle_layout_err(err, span, ty) + } +} + +impl<'tcx> FnAbiOfHelpers<'tcx> for FunctionCx<'_, '_, 'tcx> { + type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>; + + #[inline] + fn handle_fn_abi_err( + &self, + err: FnAbiError<'tcx>, + span: Span, + fn_abi_request: FnAbiRequest<'tcx>, + ) -> ! { + RevealAllLayoutCx(self.tcx).handle_fn_abi_err(err, span, fn_abi_request) + } +} + +impl<'tcx> layout::HasTyCtxt<'tcx> for FunctionCx<'_, '_, 'tcx> { + fn tcx<'b>(&'b self) -> TyCtxt<'tcx> { + self.tcx + } +} + +impl<'tcx> rustc_target::abi::HasDataLayout for FunctionCx<'_, '_, 'tcx> { + fn data_layout(&self) -> &rustc_target::abi::TargetDataLayout { + &self.tcx.data_layout + } +} + +impl<'tcx> layout::HasParamEnv<'tcx> for FunctionCx<'_, '_, 'tcx> { + fn param_env(&self) -> ParamEnv<'tcx> { + ParamEnv::reveal_all() + } +} + +impl<'tcx> HasTargetSpec for FunctionCx<'_, '_, 'tcx> { + fn target_spec(&self) -> &Target { + &self.tcx.sess.target + } +} + +impl<'tcx> FunctionCx<'_, '_, 'tcx> { + pub(crate) fn monomorphize<T>(&self, value: T) -> T + where + T: TypeFoldable<TyCtxt<'tcx>> + Copy, + { + self.instance.instantiate_mir_and_normalize_erasing_regions( + self.tcx, + ty::ParamEnv::reveal_all(), + ty::EarlyBinder::bind(value), + ) + } + + pub(crate) fn clif_type(&self, ty: Ty<'tcx>) -> Option<Type> { + clif_type_from_ty(self.tcx, ty) + } + + pub(crate) fn clif_pair_type(&self, ty: Ty<'tcx>) -> Option<(Type, Type)> { + clif_pair_type_from_ty(self.tcx, ty) + } + + pub(crate) fn get_block(&self, bb: BasicBlock) -> Block { + *self.block_map.get(bb).unwrap() + } + + pub(crate) fn get_local_place(&mut self, local: Local) -> CPlace<'tcx> { + *self.local_map.get(local).unwrap_or_else(|| { + panic!("Local {:?} doesn't exist", local); + }) + } + + pub(crate) fn create_stack_slot(&mut self, size: u32, align: u32) -> Pointer { + let abi_align = if self.tcx.sess.target.arch == "s390x" { 8 } else { 16 }; + if align <= abi_align { + let stack_slot = self.bcx.create_sized_stack_slot(StackSlotData { + kind: StackSlotKind::ExplicitSlot, + // FIXME Don't force the size to a multiple of <abi_align> bytes once Cranelift gets + // a way to specify stack slot alignment. + size: (size + abi_align - 1) / abi_align * abi_align, + }); + Pointer::stack_slot(stack_slot) + } else { + // Alignment is too big to handle using the above hack. Dynamically realign a stack slot + // instead. This wastes some space for the realignment. + let stack_slot = self.bcx.create_sized_stack_slot(StackSlotData { + kind: StackSlotKind::ExplicitSlot, + // FIXME Don't force the size to a multiple of <abi_align> bytes once Cranelift gets + // a way to specify stack slot alignment. + size: (size + align) / abi_align * abi_align, + }); + let base_ptr = self.bcx.ins().stack_addr(self.pointer_type, stack_slot, 0); + let misalign_offset = self.bcx.ins().urem_imm(base_ptr, i64::from(align)); + let realign_offset = self.bcx.ins().irsub_imm(misalign_offset, i64::from(align)); + Pointer::new(self.bcx.ins().iadd(base_ptr, realign_offset)) + } + } + + pub(crate) fn set_debug_loc(&mut self, source_info: mir::SourceInfo) { + if let Some(debug_context) = &mut self.cx.debug_context { + let (file_id, line, column) = + debug_context.get_span_loc(self.tcx, self.mir.span, source_info.span); + + let source_loc = + self.func_debug_cx.as_mut().unwrap().add_dbg_loc(file_id, line, column); + self.bcx.set_srcloc(source_loc); + } + } + + pub(crate) fn get_caller_location(&mut self, source_info: mir::SourceInfo) -> CValue<'tcx> { + self.mir.caller_location_span(source_info, self.caller_location, self.tcx, |span| { + let const_loc = self.tcx.span_as_caller_location(span); + crate::constant::codegen_const_value(self, const_loc, self.tcx.caller_location_ty()) + }) + } + + pub(crate) fn anonymous_str(&mut self, msg: &str) -> Value { + let mut data = DataDescription::new(); + data.define(msg.as_bytes().to_vec().into_boxed_slice()); + let msg_id = self.module.declare_anonymous_data(false, false).unwrap(); + + // Ignore DuplicateDefinition error, as the data will be the same + let _ = self.module.define_data(msg_id, &data); + + let local_msg_id = self.module.declare_data_in_func(msg_id, self.bcx.func); + if self.clif_comments.enabled() { + self.add_comment(local_msg_id, msg); + } + self.bcx.ins().global_value(self.pointer_type, local_msg_id) + } +} + +pub(crate) struct RevealAllLayoutCx<'tcx>(pub(crate) TyCtxt<'tcx>); + +impl<'tcx> LayoutOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> { + type LayoutOfResult = TyAndLayout<'tcx>; + + #[inline] + fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! { + if let LayoutError::SizeOverflow(_) | LayoutError::ReferencesError(_) = err { + self.0.sess.dcx().span_fatal(span, err.to_string()) + } else { + self.0 + .sess + .dcx() + .span_fatal(span, format!("failed to get layout for `{}`: {}", ty, err)) + } + } +} + +impl<'tcx> FnAbiOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> { + type FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>; + + #[inline] + fn handle_fn_abi_err( + &self, + err: FnAbiError<'tcx>, + span: Span, + fn_abi_request: FnAbiRequest<'tcx>, + ) -> ! { + if let FnAbiError::Layout(LayoutError::SizeOverflow(_)) = err { + self.0.sess.dcx().emit_fatal(Spanned { span, node: err }) + } else { + match fn_abi_request { + FnAbiRequest::OfFnPtr { sig, extra_args } => { + span_bug!(span, "`fn_abi_of_fn_ptr({sig}, {extra_args:?})` failed: {err:?}"); + } + FnAbiRequest::OfInstance { instance, extra_args } => { + span_bug!( + span, + "`fn_abi_of_instance({instance}, {extra_args:?})` failed: {err:?}" + ); + } + } + } + } +} + +impl<'tcx> layout::HasTyCtxt<'tcx> for RevealAllLayoutCx<'tcx> { + fn tcx<'b>(&'b self) -> TyCtxt<'tcx> { + self.0 + } +} + +impl<'tcx> rustc_target::abi::HasDataLayout for RevealAllLayoutCx<'tcx> { + fn data_layout(&self) -> &rustc_target::abi::TargetDataLayout { + &self.0.data_layout + } +} + +impl<'tcx> layout::HasParamEnv<'tcx> for RevealAllLayoutCx<'tcx> { + fn param_env(&self) -> ParamEnv<'tcx> { + ParamEnv::reveal_all() + } +} + +impl<'tcx> HasTargetSpec for RevealAllLayoutCx<'tcx> { + fn target_spec(&self) -> &Target { + &self.0.sess.target + } +} |