diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/builder/autodiff.rs | 178 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/context.rs | 5 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/intrinsic.rs | 212 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/lib.rs | 6 |
4 files changed, 230 insertions, 171 deletions
diff --git a/compiler/rustc_codegen_llvm/src/builder/autodiff.rs b/compiler/rustc_codegen_llvm/src/builder/autodiff.rs index 66c34fbcfb1..56116959a62 100644 --- a/compiler/rustc_codegen_llvm/src/builder/autodiff.rs +++ b/compiler/rustc_codegen_llvm/src/builder/autodiff.rs @@ -1,40 +1,93 @@ use std::ptr; -use rustc_ast::expand::autodiff_attrs::{AutoDiffAttrs, AutoDiffItem, DiffActivity, DiffMode}; -use rustc_codegen_ssa::ModuleCodegen; +use rustc_ast::expand::autodiff_attrs::{AutoDiffAttrs, DiffActivity, DiffMode}; use rustc_codegen_ssa::common::TypeKind; use rustc_codegen_ssa::traits::{BaseTypeCodegenMethods, BuilderMethods}; -use rustc_errors::FatalError; -use rustc_middle::bug; -use tracing::{debug, trace}; +use rustc_middle::ty::{PseudoCanonicalInput, Ty, TyCtxt, TypingEnv}; +use rustc_middle::{bug, ty}; +use tracing::debug; -use crate::back::write::llvm_err; use crate::builder::{Builder, PlaceRef, UNNAMED}; use crate::context::SimpleCx; use crate::declare::declare_simple_fn; -use crate::errors::{AutoDiffWithoutEnable, LlvmError}; use crate::llvm::AttributePlace::Function; use crate::llvm::{Metadata, True, Type}; use crate::value::Value; -use crate::{CodegenContext, LlvmCodegenBackend, ModuleLlvm, attributes, llvm}; +use crate::{attributes, llvm}; -fn _get_params(fnc: &Value) -> Vec<&Value> { - let param_num = llvm::LLVMCountParams(fnc) as usize; - let mut fnc_args: Vec<&Value> = vec![]; - fnc_args.reserve(param_num); - unsafe { - llvm::LLVMGetParams(fnc, fnc_args.as_mut_ptr()); - fnc_args.set_len(param_num); +pub(crate) fn adjust_activity_to_abi<'tcx>( + tcx: TyCtxt<'tcx>, + fn_ty: Ty<'tcx>, + da: &mut Vec<DiffActivity>, +) { + if !matches!(fn_ty.kind(), ty::FnDef(..)) { + bug!("expected fn def for autodiff, got {:?}", fn_ty); } - fnc_args -} -fn _has_sret(fnc: &Value) -> bool { - let num_args = llvm::LLVMCountParams(fnc) as usize; - if num_args == 0 { - false - } else { - unsafe { llvm::LLVMRustHasAttributeAtIndex(fnc, 0, llvm::AttributeKind::StructRet) } + // We don't actually pass the types back into the type system. + // All we do is decide how to handle the arguments. + let sig = fn_ty.fn_sig(tcx).skip_binder(); + + let mut new_activities = vec![]; + let mut new_positions = vec![]; + for (i, ty) in sig.inputs().iter().enumerate() { + if let Some(inner_ty) = ty.builtin_deref(true) { + if inner_ty.is_slice() { + // Now we need to figure out the size of each slice element in memory to allow + // safety checks and usability improvements in the backend. + let sty = match inner_ty.builtin_index() { + Some(sty) => sty, + None => { + panic!("slice element type unknown"); + } + }; + let pci = PseudoCanonicalInput { + typing_env: TypingEnv::fully_monomorphized(), + value: sty, + }; + + let layout = tcx.layout_of(pci); + let elem_size = match layout { + Ok(layout) => layout.size, + Err(_) => { + bug!("autodiff failed to compute slice element size"); + } + }; + let elem_size: u32 = elem_size.bytes() as u32; + + // We know that the length will be passed as extra arg. + if !da.is_empty() { + // We are looking at a slice. The length of that slice will become an + // extra integer on llvm level. Integers are always const. + // However, if the slice get's duplicated, we want to know to later check the + // size. So we mark the new size argument as FakeActivitySize. + // There is one FakeActivitySize per slice, so for convenience we store the + // slice element size in bytes in it. We will use the size in the backend. + let activity = match da[i] { + DiffActivity::DualOnly + | DiffActivity::Dual + | DiffActivity::Dualv + | DiffActivity::DuplicatedOnly + | DiffActivity::Duplicated => { + DiffActivity::FakeActivitySize(Some(elem_size)) + } + DiffActivity::Const => DiffActivity::Const, + _ => bug!("unexpected activity for ptr/ref"), + }; + new_activities.push(activity); + new_positions.push(i + 1); + } + + continue; + } + } + } + // now add the extra activities coming from slices + // Reverse order to not invalidate the indices + for _ in 0..new_activities.len() { + let pos = new_positions.pop().unwrap(); + let activity = new_activities.pop().unwrap(); + da.insert(pos, activity); } } @@ -66,12 +119,12 @@ fn match_args_from_caller_to_enzyme<'ll, 'tcx>( let mut outer_pos: usize = 0; let mut activity_pos = 0; - let enzyme_const = cx.create_metadata("enzyme_const".to_string()).unwrap(); - let enzyme_out = cx.create_metadata("enzyme_out".to_string()).unwrap(); - let enzyme_dup = cx.create_metadata("enzyme_dup".to_string()).unwrap(); - let enzyme_dupv = cx.create_metadata("enzyme_dupv".to_string()).unwrap(); - let enzyme_dupnoneed = cx.create_metadata("enzyme_dupnoneed".to_string()).unwrap(); - let enzyme_dupnoneedv = cx.create_metadata("enzyme_dupnoneedv".to_string()).unwrap(); + let enzyme_const = cx.create_metadata(b"enzyme_const"); + let enzyme_out = cx.create_metadata(b"enzyme_out"); + let enzyme_dup = cx.create_metadata(b"enzyme_dup"); + let enzyme_dupv = cx.create_metadata(b"enzyme_dupv"); + let enzyme_dupnoneed = cx.create_metadata(b"enzyme_dupnoneed"); + let enzyme_dupnoneedv = cx.create_metadata(b"enzyme_dupnoneedv"); while activity_pos < inputs.len() { let diff_activity = inputs[activity_pos as usize]; @@ -223,7 +276,7 @@ pub(crate) fn generate_enzyme_call<'ll, 'tcx>( // %0 = fmul double %x, %x // ret double %0 // } - // ``` + // // define double @dsquare(double %x) { // return 0.0; // } @@ -245,8 +298,7 @@ pub(crate) fn generate_enzyme_call<'ll, 'tcx>( // FIXME(ZuseZ4): the CC/Addr/Vis values are best effort guesses, we should look at tests and // think a bit more about what should go here. - // FIXME(Sa4dUs): have to find a way to get the cc, using `FastCallConv` for now - let cc = 8; + let cc = unsafe { llvm::LLVMGetFunctionCallConv(fn_to_diff) }; let ad_fn = declare_simple_fn( cx, &ad_name, @@ -265,12 +317,12 @@ pub(crate) fn generate_enzyme_call<'ll, 'tcx>( let mut args = Vec::with_capacity(num_args as usize + 1); args.push(fn_to_diff); - let enzyme_primal_ret = cx.create_metadata("enzyme_primal_return".to_string()).unwrap(); + let enzyme_primal_ret = cx.create_metadata(b"enzyme_primal_return"); if matches!(attrs.ret_activity, DiffActivity::Dual | DiffActivity::Active) { args.push(cx.get_metadata_value(enzyme_primal_ret)); } if attrs.width > 1 { - let enzyme_width = cx.create_metadata("enzyme_width".to_string()).unwrap(); + let enzyme_width = cx.create_metadata(b"enzyme_width"); args.push(cx.get_metadata_value(enzyme_width)); args.push(cx.get_const_int(cx.type_i64(), attrs.width as u64)); } @@ -288,61 +340,3 @@ pub(crate) fn generate_enzyme_call<'ll, 'tcx>( builder.store_to_place(call, dest.val); } - -pub(crate) fn differentiate<'ll>( - module: &'ll ModuleCodegen<ModuleLlvm>, - cgcx: &CodegenContext<LlvmCodegenBackend>, - diff_items: Vec<AutoDiffItem>, -) -> Result<(), FatalError> { - // TODO(Sa4dUs): delete all this logic - for item in &diff_items { - trace!("{}", item); - } - - let diag_handler = cgcx.create_dcx(); - - let cx = SimpleCx::new(module.module_llvm.llmod(), module.module_llvm.llcx, cgcx.pointer_size); - - // First of all, did the user try to use autodiff without using the -Zautodiff=Enable flag? - if !diff_items.is_empty() - && !cgcx.opts.unstable_opts.autodiff.contains(&rustc_session::config::AutoDiff::Enable) - { - return Err(diag_handler.handle().emit_almost_fatal(AutoDiffWithoutEnable)); - } - - // Here we replace the placeholder code with the actual autodiff code, which calls Enzyme. - for item in diff_items.iter() { - let name = item.source.clone(); - let fn_def: Option<&llvm::Value> = cx.get_function(&name); - let Some(_fn_def) = fn_def else { - return Err(llvm_err( - diag_handler.handle(), - LlvmError::PrepareAutoDiff { - src: item.source.clone(), - target: item.target.clone(), - error: "could not find source function".to_owned(), - }, - )); - }; - debug!(?item.target); - let fn_target: Option<&llvm::Value> = cx.get_function(&item.target); - let Some(_fn_target) = fn_target else { - return Err(llvm_err( - diag_handler.handle(), - LlvmError::PrepareAutoDiff { - src: item.source.clone(), - target: item.target.clone(), - error: "could not find target function".to_owned(), - }, - )); - }; - - // generate_enzyme_call(&cx, fn_def, fn_target, item.attrs.clone()); - } - - // FIXME(ZuseZ4): support SanitizeHWAddress and prevent illegal/unsupported opts - - trace!("done with differentiate()"); - - Ok(()) -} diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs index 8eb15571e82..da8c1e5f47b 100644 --- a/compiler/rustc_codegen_llvm/src/context.rs +++ b/compiler/rustc_codegen_llvm/src/context.rs @@ -8,7 +8,6 @@ use std::str; use rustc_abi::{HasDataLayout, Size, TargetDataLayout, VariantIdx}; use rustc_codegen_ssa::back::versioned_llvm_target; use rustc_codegen_ssa::base::{wants_msvc_seh, wants_wasm_eh}; -use rustc_codegen_ssa::common::TypeKind; use rustc_codegen_ssa::errors as ssa_errors; use rustc_codegen_ssa::traits::*; use rustc_data_structures::base_n::{ALPHANUMERIC_ONLY, ToBaseN}; @@ -660,10 +659,6 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> { } } impl<'ll> SimpleCx<'ll> { - pub(crate) fn _get_return_type(&self, ty: &'ll Type) -> &'ll Type { - assert_eq!(self.type_kind(ty), TypeKind::Function); - unsafe { llvm::LLVMGetReturnType(ty) } - } pub(crate) fn get_type_of_global(&self, val: &'ll Value) -> &'ll Type { unsafe { llvm::LLVMGlobalGetValueType(val) } } diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs index 1102fc1d0c8..4935f8d7dff 100644 --- a/compiler/rustc_codegen_llvm/src/intrinsic.rs +++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs @@ -9,21 +9,23 @@ use rustc_codegen_ssa::errors::{ExpectedPointerMutability, InvalidMonomorphizati use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue}; use rustc_codegen_ssa::mir::place::{PlaceRef, PlaceValue}; use rustc_codegen_ssa::traits::*; -use rustc_hir as hir; use rustc_hir::def_id::LOCAL_CRATE; +use rustc_hir::{self as hir}; use rustc_middle::mir::BinOp; use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv, LayoutOf}; -use rustc_middle::ty::{self, GenericArgsRef, Instance, Ty}; +use rustc_middle::ty::{self, GenericArgsRef, Instance, Ty, TyCtxt, TypingEnv}; use rustc_middle::{bug, span_bug}; use rustc_span::{Span, Symbol, sym}; use rustc_symbol_mangling::{mangle_internal_symbol, symbol_name_for_instance_in_crate}; +use rustc_target::callconv::PassMode; use rustc_target::spec::PanicStrategy; use tracing::debug; use crate::abi::FnAbiLlvmExt; use crate::builder::Builder; -use crate::builder::autodiff::generate_enzyme_call; +use crate::builder::autodiff::{adjust_activity_to_abi, generate_enzyme_call}; use crate::context::CodegenCx; +use crate::errors::AutoDiffWithoutEnable; use crate::llvm::{self, Metadata}; use crate::type_::Type; use crate::type_of::LayoutLlvmExt; @@ -177,16 +179,9 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> { span: Span, ) -> Result<(), ty::Instance<'tcx>> { let tcx = self.tcx; - let callee_ty = instance.ty(tcx, self.typing_env()); - let fn_args = instance.args; - - let sig = callee_ty.fn_sig(tcx); - let sig = tcx.normalize_erasing_late_bound_regions(self.typing_env(), sig); - let ret_ty = sig.output(); let name = tcx.item_name(instance.def_id()); - - let llret_ty = self.layout_of(ret_ty).llvm_type(self); + let fn_args = instance.args; let simple = call_simple_intrinsic(self, name, args); let llval = match name { @@ -200,63 +195,7 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> { ) } sym::autodiff => { - let val_arr: Vec<&'ll Value> = match args[2].val { - crate::intrinsic::OperandValue::Ref(ref place_value) => { - let mut ret_arr = vec![]; - let tuple_place = PlaceRef { val: *place_value, layout: args[2].layout }; - - for i in 0..tuple_place.layout.layout.0.fields.count() { - let field_place = tuple_place.project_field(self, i); - let field_layout = tuple_place.layout.field(self, i); - let llvm_ty = field_layout.llvm_type(self.cx); - - let field_val = - self.load(llvm_ty, field_place.val.llval, field_place.val.align); - - ret_arr.push(field_val) - } - - ret_arr - } - crate::intrinsic::OperandValue::Pair(v1, v2) => vec![v1, v2], - OperandValue::Immediate(v) => vec![v], - OperandValue::ZeroSized => bug!("unexpected `ZeroSized` arg"), - }; - - // Get source, diff, and attrs - let source_id = match fn_args.into_type_list(tcx)[0].kind() { - ty::FnDef(def_id, _) => def_id, - _ => bug!("invalid args"), - }; - let fn_source = Instance::mono(tcx, *source_id); - let source_symbol = - symbol_name_for_instance_in_crate(tcx, fn_source.clone(), LOCAL_CRATE); - let fn_to_diff: Option<&'ll llvm::Value> = self.cx.get_function(&source_symbol); - let Some(fn_to_diff) = fn_to_diff else { bug!("could not find source function") }; - - let diff_id = match fn_args.into_type_list(tcx)[1].kind() { - ty::FnDef(def_id, _) => def_id, - _ => bug!("invalid args"), - }; - let fn_diff = Instance::mono(tcx, *diff_id); - let diff_symbol = - symbol_name_for_instance_in_crate(tcx, fn_diff.clone(), LOCAL_CRATE); - - let diff_attrs = autodiff_attrs(tcx, *diff_id); - let Some(diff_attrs) = diff_attrs else { bug!("could not find autodiff attrs") }; - - // Build body - generate_enzyme_call( - self, - self.cx, - fn_to_diff, - &diff_symbol, - llret_ty, - &val_arr, - diff_attrs.clone(), - result, - ); - + codegen_autodiff(self, tcx, instance, args, result); return Ok(()); } sym::is_val_statically_known => { @@ -1183,6 +1122,143 @@ fn get_rust_try_fn<'a, 'll, 'tcx>( rust_try } +fn codegen_autodiff<'ll, 'tcx>( + bx: &mut Builder<'_, 'll, 'tcx>, + tcx: TyCtxt<'tcx>, + instance: ty::Instance<'tcx>, + args: &[OperandRef<'tcx, &'ll Value>], + result: PlaceRef<'tcx, &'ll Value>, +) { + if !tcx.sess.opts.unstable_opts.autodiff.contains(&rustc_session::config::AutoDiff::Enable) { + let _ = tcx.dcx().emit_almost_fatal(AutoDiffWithoutEnable); + } + + let fn_args = instance.args; + let callee_ty = instance.ty(tcx, bx.typing_env()); + + let sig = callee_ty.fn_sig(tcx).skip_binder(); + + let ret_ty = sig.output(); + let llret_ty = bx.layout_of(ret_ty).llvm_type(bx); + + // Get source, diff, and attrs + let (source_id, source_args) = match fn_args.into_type_list(tcx)[0].kind() { + ty::FnDef(def_id, source_params) => (def_id, source_params), + _ => bug!("invalid autodiff intrinsic args"), + }; + + let fn_source = match Instance::try_resolve(tcx, bx.cx.typing_env(), *source_id, source_args) { + Ok(Some(instance)) => instance, + Ok(None) => bug!( + "could not resolve ({:?}, {:?}) to a specific autodiff instance", + source_id, + source_args + ), + Err(_) => { + // An error has already been emitted + return; + } + }; + + let source_symbol = symbol_name_for_instance_in_crate(tcx, fn_source.clone(), LOCAL_CRATE); + let Some(fn_to_diff) = bx.cx.get_function(&source_symbol) else { + bug!("could not find source function") + }; + + let (diff_id, diff_args) = match fn_args.into_type_list(tcx)[1].kind() { + ty::FnDef(def_id, diff_args) => (def_id, diff_args), + _ => bug!("invalid args"), + }; + + let fn_diff = match Instance::try_resolve(tcx, bx.cx.typing_env(), *diff_id, diff_args) { + Ok(Some(instance)) => instance, + Ok(None) => bug!( + "could not resolve ({:?}, {:?}) to a specific autodiff instance", + diff_id, + diff_args + ), + Err(_) => { + // An error has already been emitted + return; + } + }; + + let val_arr = get_args_from_tuple(bx, args[2], fn_diff); + let diff_symbol = symbol_name_for_instance_in_crate(tcx, fn_diff.clone(), LOCAL_CRATE); + + let Some(mut diff_attrs) = autodiff_attrs(tcx, fn_diff.def_id()) else { + bug!("could not find autodiff attrs") + }; + + adjust_activity_to_abi( + tcx, + fn_source.ty(tcx, TypingEnv::fully_monomorphized()), + &mut diff_attrs.input_activity, + ); + + // Build body + generate_enzyme_call( + bx, + bx.cx, + fn_to_diff, + &diff_symbol, + llret_ty, + &val_arr, + diff_attrs.clone(), + result, + ); +} + +fn get_args_from_tuple<'ll, 'tcx>( + bx: &mut Builder<'_, 'll, 'tcx>, + tuple_op: OperandRef<'tcx, &'ll Value>, + fn_instance: Instance<'tcx>, +) -> Vec<&'ll Value> { + let cx = bx.cx; + let fn_abi = cx.fn_abi_of_instance(fn_instance, ty::List::empty()); + + match tuple_op.val { + OperandValue::Immediate(val) => vec![val], + OperandValue::Pair(v1, v2) => vec![v1, v2], + OperandValue::Ref(ptr) => { + let tuple_place = PlaceRef { val: ptr, layout: tuple_op.layout }; + + let mut result = Vec::with_capacity(fn_abi.args.len()); + let mut tuple_index = 0; + + for arg in &fn_abi.args { + match arg.mode { + PassMode::Ignore => {} + PassMode::Direct(_) | PassMode::Cast { .. } => { + let field = tuple_place.project_field(bx, tuple_index); + let llvm_ty = field.layout.llvm_type(bx.cx); + let val = bx.load(llvm_ty, field.val.llval, field.val.align); + result.push(val); + tuple_index += 1; + } + PassMode::Pair(_, _) => { + let field = tuple_place.project_field(bx, tuple_index); + let llvm_ty = field.layout.llvm_type(bx.cx); + let pair_val = bx.load(llvm_ty, field.val.llval, field.val.align); + result.push(bx.extract_value(pair_val, 0)); + result.push(bx.extract_value(pair_val, 1)); + tuple_index += 1; + } + PassMode::Indirect { .. } => { + let field = tuple_place.project_field(bx, tuple_index); + result.push(field.val.llval); + tuple_index += 1; + } + } + } + + result + } + + OperandValue::ZeroSized => vec![], + } +} + fn generic_simd_intrinsic<'ll, 'tcx>( bx: &mut Builder<'_, 'll, 'tcx>, name: Symbol, diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs index ca84b6de8b1..79e80db6f55 100644 --- a/compiler/rustc_codegen_llvm/src/lib.rs +++ b/compiler/rustc_codegen_llvm/src/lib.rs @@ -30,7 +30,6 @@ use context::SimpleCx; use errors::ParseTargetMachineConfig; use llvm_util::target_config; use rustc_ast::expand::allocator::AllocatorKind; -use rustc_ast::expand::autodiff_attrs::AutoDiffItem; use rustc_codegen_ssa::back::lto::{SerializedModule, ThinModule}; use rustc_codegen_ssa::back::write::{ CodegenContext, FatLtoInput, ModuleConfig, TargetMachineFactoryConfig, TargetMachineFactoryFn, @@ -173,15 +172,10 @@ impl WriteBackendMethods for LlvmCodegenBackend { exported_symbols_for_lto: &[String], each_linked_rlib_for_lto: &[PathBuf], modules: Vec<FatLtoInput<Self>>, - diff_fncs: Vec<AutoDiffItem>, ) -> Result<ModuleCodegen<Self::Module>, FatalError> { let mut module = back::lto::run_fat(cgcx, exported_symbols_for_lto, each_linked_rlib_for_lto, modules)?; - if !diff_fncs.is_empty() { - builder::autodiff::differentiate(&module, cgcx, diff_fncs)?; - } - let dcx = cgcx.create_dcx(); let dcx = dcx.handle(); back::lto::run_pass_manager(cgcx, dcx, &mut module, false)?; |