use crate::abi::{Abi, FnAbi, FnAbiLlvmExt, LlvmType, PassMode}; use crate::builder::Builder; use crate::context::CodegenCx; use crate::llvm; use crate::type_::Type; use crate::type_of::LayoutLlvmExt; use crate::va_arg::emit_va_arg; use crate::value::Value; use rustc_codegen_ssa::base::{compare_simd_types, wants_msvc_seh}; use rustc_codegen_ssa::common::span_invalid_monomorphization_error; use rustc_codegen_ssa::common::{IntPredicate, TypeKind}; use rustc_codegen_ssa::mir::operand::OperandRef; use rustc_codegen_ssa::mir::place::PlaceRef; use rustc_codegen_ssa::traits::*; use rustc_hir as hir; use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, LayoutOf}; use rustc_middle::ty::{self, Ty}; use rustc_middle::{bug, span_bug}; use rustc_span::{sym, symbol::kw, Span, Symbol}; use rustc_target::abi::{self, Align, HasDataLayout, Primitive}; use rustc_target::spec::{HasTargetSpec, PanicStrategy}; use std::cmp::Ordering; use std::iter; fn get_simple_intrinsic<'ll>( cx: &CodegenCx<'ll, '_>, name: Symbol, ) -> Option<(&'ll Type, &'ll Value)> { let llvm_name = match name { sym::sqrtf32 => "llvm.sqrt.f32", sym::sqrtf64 => "llvm.sqrt.f64", sym::powif32 => "llvm.powi.f32", sym::powif64 => "llvm.powi.f64", sym::sinf32 => "llvm.sin.f32", sym::sinf64 => "llvm.sin.f64", sym::cosf32 => "llvm.cos.f32", sym::cosf64 => "llvm.cos.f64", sym::powf32 => "llvm.pow.f32", sym::powf64 => "llvm.pow.f64", sym::expf32 => "llvm.exp.f32", sym::expf64 => "llvm.exp.f64", sym::exp2f32 => "llvm.exp2.f32", sym::exp2f64 => "llvm.exp2.f64", sym::logf32 => "llvm.log.f32", sym::logf64 => "llvm.log.f64", sym::log10f32 => "llvm.log10.f32", sym::log10f64 => "llvm.log10.f64", sym::log2f32 => "llvm.log2.f32", sym::log2f64 => "llvm.log2.f64", sym::fmaf32 => "llvm.fma.f32", sym::fmaf64 => "llvm.fma.f64", sym::fabsf32 => "llvm.fabs.f32", sym::fabsf64 => "llvm.fabs.f64", sym::minnumf32 => "llvm.minnum.f32", sym::minnumf64 => "llvm.minnum.f64", sym::maxnumf32 => "llvm.maxnum.f32", sym::maxnumf64 => "llvm.maxnum.f64", sym::copysignf32 => "llvm.copysign.f32", sym::copysignf64 => "llvm.copysign.f64", sym::floorf32 => "llvm.floor.f32", sym::floorf64 => "llvm.floor.f64", sym::ceilf32 => "llvm.ceil.f32", sym::ceilf64 => "llvm.ceil.f64", sym::truncf32 => "llvm.trunc.f32", sym::truncf64 => "llvm.trunc.f64", sym::rintf32 => "llvm.rint.f32", sym::rintf64 => "llvm.rint.f64", sym::nearbyintf32 => "llvm.nearbyint.f32", sym::nearbyintf64 => "llvm.nearbyint.f64", sym::roundf32 => "llvm.round.f32", sym::roundf64 => "llvm.round.f64", sym::ptr_mask => "llvm.ptrmask", _ => return None, }; Some(cx.get_intrinsic(llvm_name)) } impl<'ll, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'_, 'll, 'tcx> { fn codegen_intrinsic_call( &mut self, instance: ty::Instance<'tcx>, fn_abi: &FnAbi<'tcx, Ty<'tcx>>, args: &[OperandRef<'tcx, &'ll Value>], llresult: &'ll Value, span: Span, ) { let tcx = self.tcx; let callee_ty = instance.ty(tcx, ty::ParamEnv::reveal_all()); let ty::FnDef(def_id, substs) = *callee_ty.kind() else { bug!("expected fn item type, found {}", callee_ty); }; let sig = callee_ty.fn_sig(tcx); let sig = tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), sig); let arg_tys = sig.inputs(); let ret_ty = sig.output(); let name = tcx.item_name(def_id); let llret_ty = self.layout_of(ret_ty).llvm_type(self); let result = PlaceRef::new_sized(llresult, fn_abi.ret.layout); let simple = get_simple_intrinsic(self, name); let llval = match name { _ if simple.is_some() => { let (simple_ty, simple_fn) = simple.unwrap(); self.call( simple_ty, None, simple_fn, &args.iter().map(|arg| arg.immediate()).collect::>(), None, ) } sym::likely => { self.call_intrinsic("llvm.expect.i1", &[args[0].immediate(), self.const_bool(true)]) } sym::unlikely => self .call_intrinsic("llvm.expect.i1", &[args[0].immediate(), self.const_bool(false)]), kw::Try => { try_intrinsic( self, args[0].immediate(), args[1].immediate(), args[2].immediate(), llresult, ); return; } sym::breakpoint => self.call_intrinsic("llvm.debugtrap", &[]), sym::va_copy => { self.call_intrinsic("llvm.va_copy", &[args[0].immediate(), args[1].immediate()]) } sym::va_arg => { match fn_abi.ret.layout.abi { abi::Abi::Scalar(scalar) => { match scalar.primitive() { Primitive::Int(..) => { if self.cx().size_of(ret_ty).bytes() < 4 { // `va_arg` should not be called on an integer type // less than 4 bytes in length. If it is, promote // the integer to an `i32` and truncate the result // back to the smaller type. let promoted_result = emit_va_arg(self, args[0], tcx.types.i32); self.trunc(promoted_result, llret_ty) } else { emit_va_arg(self, args[0], ret_ty) } } Primitive::F64 | Primitive::Pointer => { emit_va_arg(self, args[0], ret_ty) } // `va_arg` should never be used with the return type f32. Primitive::F32 => bug!("the va_arg intrinsic does not work with `f32`"), } } _ => bug!("the va_arg intrinsic does not work with non-scalar types"), } } sym::volatile_load | sym::unaligned_volatile_load => { let tp_ty = substs.type_at(0); let ptr = args[0].immediate(); let load = if let PassMode::Cast(ty, _) = &fn_abi.ret.mode { let llty = ty.llvm_type(self); let ptr = self.pointercast(ptr, self.type_ptr_to(llty)); self.volatile_load(llty, ptr) } else { self.volatile_load(self.layout_of(tp_ty).llvm_type(self), ptr) }; let align = if name == sym::unaligned_volatile_load { 1 } else { self.align_of(tp_ty).bytes() as u32 }; unsafe { llvm::LLVMSetAlignment(load, align); } self.to_immediate(load, self.layout_of(tp_ty)) } sym::volatile_store => { let dst = args[0].deref(self.cx()); args[1].val.volatile_store(self, dst); return; } sym::unaligned_volatile_store => { let dst = args[0].deref(self.cx()); args[1].val.unaligned_volatile_store(self, dst); return; } sym::prefetch_read_data | sym::prefetch_write_data | sym::prefetch_read_instruction | sym::prefetch_write_instruction => { let (rw, cache_type) = match name { sym::prefetch_read_data => (0, 1), sym::prefetch_write_data => (1, 1), sym::prefetch_read_instruction => (0, 0), sym::prefetch_write_instruction => (1, 0), _ => bug!(), }; self.call_intrinsic( "llvm.prefetch", &[ args[0].immediate(), self.const_i32(rw), args[1].immediate(), self.const_i32(cache_type), ], ) } sym::ctlz | sym::ctlz_nonzero | sym::cttz | sym::cttz_nonzero | sym::ctpop | sym::bswap | sym::bitreverse | sym::rotate_left | sym::rotate_right | sym::saturating_add | sym::saturating_sub => { let ty = arg_tys[0]; match int_type_width_signed(ty, self) { Some((width, signed)) => match name { sym::ctlz | sym::cttz => { let y = self.const_bool(false); self.call_intrinsic( &format!("llvm.{}.i{}", name, width), &[args[0].immediate(), y], ) } sym::ctlz_nonzero => { let y = self.const_bool(true); let llvm_name = &format!("llvm.ctlz.i{}", width); self.call_intrinsic(llvm_name, &[args[0].immediate(), y]) } sym::cttz_nonzero => { let y = self.const_bool(true); let llvm_name = &format!("llvm.cttz.i{}", width); self.call_intrinsic(llvm_name, &[args[0].immediate(), y]) } sym::ctpop => self.call_intrinsic( &format!("llvm.ctpop.i{}", width), &[args[0].immediate()], ), sym::bswap => { if width == 8 { args[0].immediate() // byte swap a u8/i8 is just a no-op } else { self.call_intrinsic( &format!("llvm.bswap.i{}", width), &[args[0].immediate()], ) } } sym::bitreverse => self.call_intrinsic( &format!("llvm.bitreverse.i{}", width), &[args[0].immediate()], ), sym::rotate_left | sym::rotate_right => { let is_left = name == sym::rotate_left; let val = args[0].immediate(); let raw_shift = args[1].immediate(); // rotate = funnel shift with first two args the same let llvm_name = &format!("llvm.fsh{}.i{}", if is_left { 'l' } else { 'r' }, width); self.call_intrinsic(llvm_name, &[val, val, raw_shift]) } sym::saturating_add | sym::saturating_sub => { let is_add = name == sym::saturating_add; let lhs = args[0].immediate(); let rhs = args[1].immediate(); let llvm_name = &format!( "llvm.{}{}.sat.i{}", if signed { 's' } else { 'u' }, if is_add { "add" } else { "sub" }, width ); self.call_intrinsic(llvm_name, &[lhs, rhs]) } _ => bug!(), }, None => { span_invalid_monomorphization_error( tcx.sess, span, &format!( "invalid monomorphization of `{}` intrinsic: \ expected basic integer type, found `{}`", name, ty ), ); return; } } } sym::raw_eq => { use abi::Abi::*; let tp_ty = substs.type_at(0); let layout = self.layout_of(tp_ty).layout; let use_integer_compare = match layout.abi() { Scalar(_) | ScalarPair(_, _) => true, Uninhabited | Vector { .. } => false, Aggregate { .. } => { // For rusty ABIs, small aggregates are actually passed // as `RegKind::Integer` (see `FnAbi::adjust_for_abi`), // so we re-use that same threshold here. layout.size() <= self.data_layout().pointer_size * 2 } }; let a = args[0].immediate(); let b = args[1].immediate(); if layout.size().bytes() == 0 { self.const_bool(true) } else if use_integer_compare { let integer_ty = self.type_ix(layout.size().bits()); let ptr_ty = self.type_ptr_to(integer_ty); let a_ptr = self.bitcast(a, ptr_ty); let a_val = self.load(integer_ty, a_ptr, layout.align().abi); let b_ptr = self.bitcast(b, ptr_ty); let b_val = self.load(integer_ty, b_ptr, layout.align().abi); self.icmp(IntPredicate::IntEQ, a_val, b_val) } else { let i8p_ty = self.type_i8p(); let a_ptr = self.bitcast(a, i8p_ty); let b_ptr = self.bitcast(b, i8p_ty); let n = self.const_usize(layout.size().bytes()); let cmp = self.call_intrinsic("memcmp", &[a_ptr, b_ptr, n]); match self.cx.sess().target.arch.as_ref() { "avr" | "msp430" => self.icmp(IntPredicate::IntEQ, cmp, self.const_i16(0)), _ => self.icmp(IntPredicate::IntEQ, cmp, self.const_i32(0)), } } } sym::black_box => { args[0].val.store(self, result); let result_val_span = [result.llval]; // We need to "use" the argument in some way LLVM can't introspect, and on // targets that support it we can typically leverage inline assembly to do // this. LLVM's interpretation of inline assembly is that it's, well, a black // box. This isn't the greatest implementation since it probably deoptimizes // more than we want, but it's so far good enough. // // For zero-sized types, the location pointed to by the result may be // uninitialized. Do not "use" the result in this case; instead just clobber // the memory. let (constraint, inputs): (&str, &[_]) = if result.layout.is_zst() { ("~{memory}", &[]) } else { ("r,~{memory}", &result_val_span) }; crate::asm::inline_asm_call( self, "", constraint, inputs, self.type_void(), true, false, llvm::AsmDialect::Att, &[span], false, None, ) .unwrap_or_else(|| bug!("failed to generate inline asm call for `black_box`")); // We have copied the value to `result` already. return; } _ if name.as_str().starts_with("simd_") => { match generic_simd_intrinsic(self, name, callee_ty, args, ret_ty, llret_ty, span) { Ok(llval) => llval, Err(()) => return, } } _ => bug!("unknown intrinsic '{}'", name), }; if !fn_abi.ret.is_ignore() { if let PassMode::Cast(ty, _) = &fn_abi.ret.mode { let ptr_llty = self.type_ptr_to(ty.llvm_type(self)); let ptr = self.pointercast(result.llval, ptr_llty); self.store(llval, ptr, result.align); } else { OperandRef::from_immediate_or_packed_pair(self, llval, result.layout) .val .store(self, result); } } } fn abort(&mut self) { self.call_intrinsic("llvm.trap", &[]); } fn assume(&mut self, val: Self::Value) { self.call_intrinsic("llvm.assume", &[val]); } fn expect(&mut self, cond: Self::Value, expected: bool) -> Self::Value { self.call_intrinsic("llvm.expect.i1", &[cond, self.const_bool(expected)]) } fn type_test(&mut self, pointer: Self::Value, typeid: Self::Value) -> Self::Value { // Test the called operand using llvm.type.test intrinsic. The LowerTypeTests link-time // optimization pass replaces calls to this intrinsic with code to test type membership. let i8p_ty = self.type_i8p(); let bitcast = self.bitcast(pointer, i8p_ty); self.call_intrinsic("llvm.type.test", &[bitcast, typeid]) } fn type_checked_load( &mut self, llvtable: &'ll Value, vtable_byte_offset: u64, typeid: &'ll Value, ) -> Self::Value { let vtable_byte_offset = self.const_i32(vtable_byte_offset as i32); self.call_intrinsic("llvm.type.checked.load", &[llvtable, vtable_byte_offset, typeid]) } fn va_start(&mut self, va_list: &'ll Value) -> &'ll Value { self.call_intrinsic("llvm.va_start", &[va_list]) } fn va_end(&mut self, va_list: &'ll Value) -> &'ll Value { self.call_intrinsic("llvm.va_end", &[va_list]) } } fn try_intrinsic<'ll>( bx: &mut Builder<'_, 'll, '_>, try_func: &'ll Value, data: &'ll Value, catch_func: &'ll Value, dest: &'ll Value, ) { if bx.sess().panic_strategy() == PanicStrategy::Abort { let try_func_ty = bx.type_func(&[bx.type_i8p()], bx.type_void()); bx.call(try_func_ty, None, try_func, &[data], None); // Return 0 unconditionally from the intrinsic call; // we can never unwind. let ret_align = bx.tcx().data_layout.i32_align.abi; bx.store(bx.const_i32(0), dest, ret_align); } else if wants_msvc_seh(bx.sess()) { codegen_msvc_try(bx, try_func, data, catch_func, dest); } else if bx.sess().target.os == "emscripten" { codegen_emcc_try(bx, try_func, data, catch_func, dest); } else { codegen_gnu_try(bx, try_func, data, catch_func, dest); } } // MSVC's definition of the `rust_try` function. // // This implementation uses the new exception handling instructions in LLVM // which have support in LLVM for SEH on MSVC targets. Although these // instructions are meant to work for all targets, as of the time of this // writing, however, LLVM does not recommend the usage of these new instructions // as the old ones are still more optimized. fn codegen_msvc_try<'ll>( bx: &mut Builder<'_, 'll, '_>, try_func: &'ll Value, data: &'ll Value, catch_func: &'ll Value, dest: &'ll Value, ) { let (llty, llfn) = get_rust_try_fn(bx, &mut |mut bx| { bx.set_personality_fn(bx.eh_personality()); let normal = bx.append_sibling_block("normal"); let catchswitch = bx.append_sibling_block("catchswitch"); let catchpad_rust = bx.append_sibling_block("catchpad_rust"); let catchpad_foreign = bx.append_sibling_block("catchpad_foreign"); let caught = bx.append_sibling_block("caught"); let try_func = llvm::get_param(bx.llfn(), 0); let data = llvm::get_param(bx.llfn(), 1); let catch_func = llvm::get_param(bx.llfn(), 2); // We're generating an IR snippet that looks like: // // declare i32 @rust_try(%try_func, %data, %catch_func) { // %slot = alloca i8* // invoke %try_func(%data) to label %normal unwind label %catchswitch // // normal: // ret i32 0 // // catchswitch: // %cs = catchswitch within none [%catchpad_rust, %catchpad_foreign] unwind to caller // // catchpad_rust: // %tok = catchpad within %cs [%type_descriptor, 8, %slot] // %ptr = load %slot // call %catch_func(%data, %ptr) // catchret from %tok to label %caught // // catchpad_foreign: // %tok = catchpad within %cs [null, 64, null] // call %catch_func(%data, null) // catchret from %tok to label %caught // // caught: // ret i32 1 // } // // This structure follows the basic usage of throw/try/catch in LLVM. // For example, compile this C++ snippet to see what LLVM generates: // // struct rust_panic { // rust_panic(const rust_panic&); // ~rust_panic(); // // void* x[2]; // }; // // int __rust_try( // void (*try_func)(void*), // void *data, // void (*catch_func)(void*, void*) noexcept // ) { // try { // try_func(data); // return 0; // } catch(rust_panic& a) { // catch_func(data, &a); // return 1; // } catch(...) { // catch_func(data, NULL); // return 1; // } // } // // More information can be found in libstd's seh.rs implementation. let ptr_align = bx.tcx().data_layout.pointer_align.abi; let slot = bx.alloca(bx.type_i8p(), ptr_align); let try_func_ty = bx.type_func(&[bx.type_i8p()], bx.type_void()); bx.invoke(try_func_ty, None, try_func, &[data], normal, catchswitch, None); bx.switch_to_block(normal); bx.ret(bx.const_i32(0)); bx.switch_to_block(catchswitch); let cs = bx.catch_switch(None, None, &[catchpad_rust, catchpad_foreign]); // We can't use the TypeDescriptor defined in libpanic_unwind because it // might be in another DLL and the SEH encoding only supports specifying // a TypeDescriptor from the current module. // // However this isn't an issue since the MSVC runtime uses string // comparison on the type name to match TypeDescriptors rather than // pointer equality. // // So instead we generate a new TypeDescriptor in each module that uses // `try` and let the linker merge duplicate definitions in the same // module. // // When modifying, make sure that the type_name string exactly matches // the one used in src/libpanic_unwind/seh.rs. let type_info_vtable = bx.declare_global("??_7type_info@@6B@", bx.type_i8p()); let type_name = bx.const_bytes(b"rust_panic\0"); let type_info = bx.const_struct(&[type_info_vtable, bx.const_null(bx.type_i8p()), type_name], false); let tydesc = bx.declare_global("__rust_panic_type_info", bx.val_ty(type_info)); unsafe { llvm::LLVMRustSetLinkage(tydesc, llvm::Linkage::LinkOnceODRLinkage); llvm::SetUniqueComdat(bx.llmod, tydesc); llvm::LLVMSetInitializer(tydesc, type_info); } // The flag value of 8 indicates that we are catching the exception by // reference instead of by value. We can't use catch by value because // that requires copying the exception object, which we don't support // since our exception object effectively contains a Box. // // Source: MicrosoftCXXABI::getAddrOfCXXCatchHandlerType in clang bx.switch_to_block(catchpad_rust); let flags = bx.const_i32(8); let funclet = bx.catch_pad(cs, &[tydesc, flags, slot]); let ptr = bx.load(bx.type_i8p(), slot, ptr_align); let catch_ty = bx.type_func(&[bx.type_i8p(), bx.type_i8p()], bx.type_void()); bx.call(catch_ty, None, catch_func, &[data, ptr], Some(&funclet)); bx.catch_ret(&funclet, caught); // The flag value of 64 indicates a "catch-all". bx.switch_to_block(catchpad_foreign); let flags = bx.const_i32(64); let null = bx.const_null(bx.type_i8p()); let funclet = bx.catch_pad(cs, &[null, flags, null]); bx.call(catch_ty, None, catch_func, &[data, null], Some(&funclet)); bx.catch_ret(&funclet, caught); bx.switch_to_block(caught); bx.ret(bx.const_i32(1)); }); // Note that no invoke is used here because by definition this function // can't panic (that's what it's catching). let ret = bx.call(llty, None, llfn, &[try_func, data, catch_func], None); let i32_align = bx.tcx().data_layout.i32_align.abi; bx.store(ret, dest, i32_align); } // Definition of the standard `try` function for Rust using the GNU-like model // of exceptions (e.g., the normal semantics of LLVM's `landingpad` and `invoke` // instructions). // // This codegen is a little surprising because we always call a shim // function instead of inlining the call to `invoke` manually here. This is done // because in LLVM we're only allowed to have one personality per function // definition. The call to the `try` intrinsic is being inlined into the // function calling it, and that function may already have other personality // functions in play. By calling a shim we're guaranteed that our shim will have // the right personality function. fn codegen_gnu_try<'ll>( bx: &mut Builder<'_, 'll, '_>, try_func: &'ll Value, data: &'ll Value, catch_func: &'ll Value, dest: &'ll Value, ) { let (llty, llfn) = get_rust_try_fn(bx, &mut |mut bx| { // Codegens the shims described above: // // bx: // invoke %try_func(%data) normal %normal unwind %catch // // normal: // ret 0 // // catch: // (%ptr, _) = landingpad // call %catch_func(%data, %ptr) // ret 1 let then = bx.append_sibling_block("then"); let catch = bx.append_sibling_block("catch"); let try_func = llvm::get_param(bx.llfn(), 0); let data = llvm::get_param(bx.llfn(), 1); let catch_func = llvm::get_param(bx.llfn(), 2); let try_func_ty = bx.type_func(&[bx.type_i8p()], bx.type_void()); bx.invoke(try_func_ty, None, try_func, &[data], then, catch, None); bx.switch_to_block(then); bx.ret(bx.const_i32(0)); // Type indicator for the exception being thrown. // // The first value in this tuple is a pointer to the exception object // being thrown. The second value is a "selector" indicating which of // the landing pad clauses the exception's type had been matched to. // rust_try ignores the selector. bx.switch_to_block(catch); let lpad_ty = bx.type_struct(&[bx.type_i8p(), bx.type_i32()], false); let vals = bx.landing_pad(lpad_ty, bx.eh_personality(), 1); let tydesc = bx.const_null(bx.type_i8p()); bx.add_clause(vals, tydesc); let ptr = bx.extract_value(vals, 0); let catch_ty = bx.type_func(&[bx.type_i8p(), bx.type_i8p()], bx.type_void()); bx.call(catch_ty, None, catch_func, &[data, ptr], None); bx.ret(bx.const_i32(1)); }); // Note that no invoke is used here because by definition this function // can't panic (that's what it's catching). let ret = bx.call(llty, None, llfn, &[try_func, data, catch_func], None); let i32_align = bx.tcx().data_layout.i32_align.abi; bx.store(ret, dest, i32_align); } // Variant of codegen_gnu_try used for emscripten where Rust panics are // implemented using C++ exceptions. Here we use exceptions of a specific type // (`struct rust_panic`) to represent Rust panics. fn codegen_emcc_try<'ll>( bx: &mut Builder<'_, 'll, '_>, try_func: &'ll Value, data: &'ll Value, catch_func: &'ll Value, dest: &'ll Value, ) { let (llty, llfn) = get_rust_try_fn(bx, &mut |mut bx| { // Codegens the shims described above: // // bx: // invoke %try_func(%data) normal %normal unwind %catch // // normal: // ret 0 // // catch: // (%ptr, %selector) = landingpad // %rust_typeid = @llvm.eh.typeid.for(@_ZTI10rust_panic) // %is_rust_panic = %selector == %rust_typeid // %catch_data = alloca { i8*, i8 } // %catch_data[0] = %ptr // %catch_data[1] = %is_rust_panic // call %catch_func(%data, %catch_data) // ret 1 let then = bx.append_sibling_block("then"); let catch = bx.append_sibling_block("catch"); let try_func = llvm::get_param(bx.llfn(), 0); let data = llvm::get_param(bx.llfn(), 1); let catch_func = llvm::get_param(bx.llfn(), 2); let try_func_ty = bx.type_func(&[bx.type_i8p()], bx.type_void()); bx.invoke(try_func_ty, None, try_func, &[data], then, catch, None); bx.switch_to_block(then); bx.ret(bx.const_i32(0)); // Type indicator for the exception being thrown. // // The first value in this tuple is a pointer to the exception object // being thrown. The second value is a "selector" indicating which of // the landing pad clauses the exception's type had been matched to. bx.switch_to_block(catch); let tydesc = bx.eh_catch_typeinfo(); let lpad_ty = bx.type_struct(&[bx.type_i8p(), bx.type_i32()], false); let vals = bx.landing_pad(lpad_ty, bx.eh_personality(), 2); bx.add_clause(vals, tydesc); bx.add_clause(vals, bx.const_null(bx.type_i8p())); let ptr = bx.extract_value(vals, 0); let selector = bx.extract_value(vals, 1); // Check if the typeid we got is the one for a Rust panic. let rust_typeid = bx.call_intrinsic("llvm.eh.typeid.for", &[tydesc]); let is_rust_panic = bx.icmp(IntPredicate::IntEQ, selector, rust_typeid); let is_rust_panic = bx.zext(is_rust_panic, bx.type_bool()); // We need to pass two values to catch_func (ptr and is_rust_panic), so // create an alloca and pass a pointer to that. let ptr_align = bx.tcx().data_layout.pointer_align.abi; let i8_align = bx.tcx().data_layout.i8_align.abi; let catch_data_type = bx.type_struct(&[bx.type_i8p(), bx.type_bool()], false); let catch_data = bx.alloca(catch_data_type, ptr_align); let catch_data_0 = bx.inbounds_gep(catch_data_type, catch_data, &[bx.const_usize(0), bx.const_usize(0)]); bx.store(ptr, catch_data_0, ptr_align); let catch_data_1 = bx.inbounds_gep(catch_data_type, catch_data, &[bx.const_usize(0), bx.const_usize(1)]); bx.store(is_rust_panic, catch_data_1, i8_align); let catch_data = bx.bitcast(catch_data, bx.type_i8p()); let catch_ty = bx.type_func(&[bx.type_i8p(), bx.type_i8p()], bx.type_void()); bx.call(catch_ty, None, catch_func, &[data, catch_data], None); bx.ret(bx.const_i32(1)); }); // Note that no invoke is used here because by definition this function // can't panic (that's what it's catching). let ret = bx.call(llty, None, llfn, &[try_func, data, catch_func], None); let i32_align = bx.tcx().data_layout.i32_align.abi; bx.store(ret, dest, i32_align); } // Helper function to give a Block to a closure to codegen a shim function. // This is currently primarily used for the `try` intrinsic functions above. fn gen_fn<'ll, 'tcx>( cx: &CodegenCx<'ll, 'tcx>, name: &str, rust_fn_sig: ty::PolyFnSig<'tcx>, codegen: &mut dyn FnMut(Builder<'_, 'll, 'tcx>), ) -> (&'ll Type, &'ll Value) { let fn_abi = cx.fn_abi_of_fn_ptr(rust_fn_sig, ty::List::empty()); let llty = fn_abi.llvm_type(cx); let llfn = cx.declare_fn(name, fn_abi); cx.set_frame_pointer_type(llfn); cx.apply_target_cpu_attr(llfn); // FIXME(eddyb) find a nicer way to do this. unsafe { llvm::LLVMRustSetLinkage(llfn, llvm::Linkage::InternalLinkage) }; let llbb = Builder::append_block(cx, llfn, "entry-block"); let bx = Builder::build(cx, llbb); codegen(bx); (llty, llfn) } // Helper function used to get a handle to the `__rust_try` function used to // catch exceptions. // // This function is only generated once and is then cached. fn get_rust_try_fn<'ll, 'tcx>( cx: &CodegenCx<'ll, 'tcx>, codegen: &mut dyn FnMut(Builder<'_, 'll, 'tcx>), ) -> (&'ll Type, &'ll Value) { if let Some(llfn) = cx.rust_try_fn.get() { return llfn; } // Define the type up front for the signature of the rust_try function. let tcx = cx.tcx; let i8p = tcx.mk_mut_ptr(tcx.types.i8); // `unsafe fn(*mut i8) -> ()` let try_fn_ty = tcx.mk_fn_ptr(ty::Binder::dummy(tcx.mk_fn_sig( iter::once(i8p), tcx.mk_unit(), false, hir::Unsafety::Unsafe, Abi::Rust, ))); // `unsafe fn(*mut i8, *mut i8) -> ()` let catch_fn_ty = tcx.mk_fn_ptr(ty::Binder::dummy(tcx.mk_fn_sig( [i8p, i8p].iter().cloned(), tcx.mk_unit(), false, hir::Unsafety::Unsafe, Abi::Rust, ))); // `unsafe fn(unsafe fn(*mut i8) -> (), *mut i8, unsafe fn(*mut i8, *mut i8) -> ()) -> i32` let rust_fn_sig = ty::Binder::dummy(cx.tcx.mk_fn_sig( [try_fn_ty, i8p, catch_fn_ty].into_iter(), tcx.types.i32, false, hir::Unsafety::Unsafe, Abi::Rust, )); let rust_try = gen_fn(cx, "__rust_try", rust_fn_sig, codegen); cx.rust_try_fn.set(Some(rust_try)); rust_try } fn generic_simd_intrinsic<'ll, 'tcx>( bx: &mut Builder<'_, 'll, 'tcx>, name: Symbol, callee_ty: Ty<'tcx>, args: &[OperandRef<'tcx, &'ll Value>], ret_ty: Ty<'tcx>, llret_ty: &'ll Type, span: Span, ) -> Result<&'ll Value, ()> { // macros for error handling: #[allow(unused_macro_rules)] macro_rules! emit_error { ($msg: tt) => { emit_error!($msg, ) }; ($msg: tt, $($fmt: tt)*) => { span_invalid_monomorphization_error( bx.sess(), span, &format!(concat!("invalid monomorphization of `{}` intrinsic: ", $msg), name, $($fmt)*)); } } macro_rules! return_error { ($($fmt: tt)*) => { { emit_error!($($fmt)*); return Err(()); } } } macro_rules! require { ($cond: expr, $($fmt: tt)*) => { if !$cond { return_error!($($fmt)*); } }; } macro_rules! require_simd { ($ty: expr, $position: expr) => { require!($ty.is_simd(), "expected SIMD {} type, found non-SIMD `{}`", $position, $ty) }; } let tcx = bx.tcx(); let sig = tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), callee_ty.fn_sig(tcx)); let arg_tys = sig.inputs(); if name == sym::simd_select_bitmask { require_simd!(arg_tys[1], "argument"); let (len, _) = arg_tys[1].simd_size_and_type(bx.tcx()); let expected_int_bits = (len.max(8) - 1).next_power_of_two(); let expected_bytes = len / 8 + ((len % 8 > 0) as u64); let mask_ty = arg_tys[0]; let mask = match mask_ty.kind() { ty::Int(i) if i.bit_width() == Some(expected_int_bits) => args[0].immediate(), ty::Uint(i) if i.bit_width() == Some(expected_int_bits) => args[0].immediate(), ty::Array(elem, len) if matches!(elem.kind(), ty::Uint(ty::UintTy::U8)) && len.try_eval_usize(bx.tcx, ty::ParamEnv::reveal_all()) == Some(expected_bytes) => { let place = PlaceRef::alloca(bx, args[0].layout); args[0].val.store(bx, place); let int_ty = bx.type_ix(expected_bytes * 8); let ptr = bx.pointercast(place.llval, bx.cx.type_ptr_to(int_ty)); bx.load(int_ty, ptr, Align::ONE) } _ => return_error!( "invalid bitmask `{}`, expected `u{}` or `[u8; {}]`", mask_ty, expected_int_bits, expected_bytes ), }; let i1 = bx.type_i1(); let im = bx.type_ix(len); let i1xn = bx.type_vector(i1, len); let m_im = bx.trunc(mask, im); let m_i1s = bx.bitcast(m_im, i1xn); return Ok(bx.select(m_i1s, args[1].immediate(), args[2].immediate())); } // every intrinsic below takes a SIMD vector as its first argument require_simd!(arg_tys[0], "input"); let in_ty = arg_tys[0]; let comparison = match name { sym::simd_eq => Some(hir::BinOpKind::Eq), sym::simd_ne => Some(hir::BinOpKind::Ne), sym::simd_lt => Some(hir::BinOpKind::Lt), sym::simd_le => Some(hir::BinOpKind::Le), sym::simd_gt => Some(hir::BinOpKind::Gt), sym::simd_ge => Some(hir::BinOpKind::Ge), _ => None, }; let (in_len, in_elem) = arg_tys[0].simd_size_and_type(bx.tcx()); if let Some(cmp_op) = comparison { require_simd!(ret_ty, "return"); let (out_len, out_ty) = ret_ty.simd_size_and_type(bx.tcx()); require!( in_len == out_len, "expected return type with length {} (same as input type `{}`), \ found `{}` with length {}", in_len, in_ty, ret_ty, out_len ); require!( bx.type_kind(bx.element_type(llret_ty)) == TypeKind::Integer, "expected return type with integer elements, found `{}` with non-integer `{}`", ret_ty, out_ty ); return Ok(compare_simd_types( bx, args[0].immediate(), args[1].immediate(), in_elem, llret_ty, cmp_op, )); } if let Some(stripped) = name.as_str().strip_prefix("simd_shuffle") { // If this intrinsic is the older "simd_shuffleN" form, simply parse the integer. // If there is no suffix, use the index array length. let n: u64 = if stripped.is_empty() { // Make sure this is actually an array, since typeck only checks the length-suffixed // version of this intrinsic. match args[2].layout.ty.kind() { ty::Array(ty, len) if matches!(ty.kind(), ty::Uint(ty::UintTy::U32)) => { len.try_eval_usize(bx.cx.tcx, ty::ParamEnv::reveal_all()).unwrap_or_else(|| { span_bug!(span, "could not evaluate shuffle index array length") }) } _ => return_error!( "simd_shuffle index must be an array of `u32`, got `{}`", args[2].layout.ty ), } } else { stripped.parse().unwrap_or_else(|_| { span_bug!(span, "bad `simd_shuffle` instruction only caught in codegen?") }) }; require_simd!(ret_ty, "return"); let (out_len, out_ty) = ret_ty.simd_size_and_type(bx.tcx()); require!( out_len == n, "expected return type of length {}, found `{}` with length {}", n, ret_ty, out_len ); require!( in_elem == out_ty, "expected return element type `{}` (element of input `{}`), \ found `{}` with element type `{}`", in_elem, in_ty, ret_ty, out_ty ); let total_len = u128::from(in_len) * 2; let vector = args[2].immediate(); let indices: Option> = (0..n) .map(|i| { let arg_idx = i; let val = bx.const_get_elt(vector, i as u64); match bx.const_to_opt_u128(val, true) { None => { emit_error!("shuffle index #{} is not a constant", arg_idx); None } Some(idx) if idx >= total_len => { emit_error!( "shuffle index #{} is out of bounds (limit {})", arg_idx, total_len ); None } Some(idx) => Some(bx.const_i32(idx as i32)), } }) .collect(); let Some(indices) = indices else { return Ok(bx.const_null(llret_ty)); }; return Ok(bx.shuffle_vector( args[0].immediate(), args[1].immediate(), bx.const_vector(&indices), )); } if name == sym::simd_insert { require!( in_elem == arg_tys[2], "expected inserted type `{}` (element of input `{}`), found `{}`", in_elem, in_ty, arg_tys[2] ); return Ok(bx.insert_element( args[0].immediate(), args[2].immediate(), args[1].immediate(), )); } if name == sym::simd_extract { require!( ret_ty == in_elem, "expected return type `{}` (element of input `{}`), found `{}`", in_elem, in_ty, ret_ty ); return Ok(bx.extract_element(args[0].immediate(), args[1].immediate())); } if name == sym::simd_select { let m_elem_ty = in_elem; let m_len = in_len; require_simd!(arg_tys[1], "argument"); let (v_len, _) = arg_tys[1].simd_size_and_type(bx.tcx()); require!( m_len == v_len, "mismatched lengths: mask length `{}` != other vector length `{}`", m_len, v_len ); match m_elem_ty.kind() { ty::Int(_) => {} _ => return_error!("mask element type is `{}`, expected `i_`", m_elem_ty), } // truncate the mask to a vector of i1s let i1 = bx.type_i1(); let i1xn = bx.type_vector(i1, m_len as u64); let m_i1s = bx.trunc(args[0].immediate(), i1xn); return Ok(bx.select(m_i1s, args[1].immediate(), args[2].immediate())); } if name == sym::simd_bitmask { // The `fn simd_bitmask(vector) -> unsigned integer` intrinsic takes a // vector mask and returns the most significant bit (MSB) of each lane in the form // of either: // * an unsigned integer // * an array of `u8` // If the vector has less than 8 lanes, a u8 is returned with zeroed trailing bits. // // The bit order of the result depends on the byte endianness, LSB-first for little // endian and MSB-first for big endian. let expected_int_bits = in_len.max(8); let expected_bytes = expected_int_bits / 8 + ((expected_int_bits % 8 > 0) as u64); // Integer vector : let (i_xn, in_elem_bitwidth) = match in_elem.kind() { ty::Int(i) => ( args[0].immediate(), i.bit_width().unwrap_or_else(|| bx.data_layout().pointer_size.bits()), ), ty::Uint(i) => ( args[0].immediate(), i.bit_width().unwrap_or_else(|| bx.data_layout().pointer_size.bits()), ), _ => return_error!( "vector argument `{}`'s element type `{}`, expected integer element type", in_ty, in_elem ), }; // Shift the MSB to the right by "in_elem_bitwidth - 1" into the first bit position. let shift_indices = vec![ bx.cx.const_int(bx.type_ix(in_elem_bitwidth), (in_elem_bitwidth - 1) as _); in_len as _ ]; let i_xn_msb = bx.lshr(i_xn, bx.const_vector(shift_indices.as_slice())); // Truncate vector to an let i1xn = bx.trunc(i_xn_msb, bx.type_vector(bx.type_i1(), in_len)); // Bitcast to iN: let i_ = bx.bitcast(i1xn, bx.type_ix(in_len)); match ret_ty.kind() { ty::Uint(i) if i.bit_width() == Some(expected_int_bits) => { // Zero-extend iN to the bitmask type: return Ok(bx.zext(i_, bx.type_ix(expected_int_bits))); } ty::Array(elem, len) if matches!(elem.kind(), ty::Uint(ty::UintTy::U8)) && len.try_eval_usize(bx.tcx, ty::ParamEnv::reveal_all()) == Some(expected_bytes) => { // Zero-extend iN to the array length: let ze = bx.zext(i_, bx.type_ix(expected_bytes * 8)); // Convert the integer to a byte array let ptr = bx.alloca(bx.type_ix(expected_bytes * 8), Align::ONE); bx.store(ze, ptr, Align::ONE); let array_ty = bx.type_array(bx.type_i8(), expected_bytes); let ptr = bx.pointercast(ptr, bx.cx.type_ptr_to(array_ty)); return Ok(bx.load(array_ty, ptr, Align::ONE)); } _ => return_error!( "cannot return `{}`, expected `u{}` or `[u8; {}]`", ret_ty, expected_int_bits, expected_bytes ), } } fn simd_simple_float_intrinsic<'ll, 'tcx>( name: Symbol, in_elem: Ty<'_>, in_ty: Ty<'_>, in_len: u64, bx: &mut Builder<'_, 'll, 'tcx>, span: Span, args: &[OperandRef<'tcx, &'ll Value>], ) -> Result<&'ll Value, ()> { #[allow(unused_macro_rules)] macro_rules! emit_error { ($msg: tt) => { emit_error!($msg, ) }; ($msg: tt, $($fmt: tt)*) => { span_invalid_monomorphization_error( bx.sess(), span, &format!(concat!("invalid monomorphization of `{}` intrinsic: ", $msg), name, $($fmt)*)); } } macro_rules! return_error { ($($fmt: tt)*) => { { emit_error!($($fmt)*); return Err(()); } } } let (elem_ty_str, elem_ty) = if let ty::Float(f) = in_elem.kind() { let elem_ty = bx.cx.type_float_from_ty(*f); match f.bit_width() { 32 => ("f32", elem_ty), 64 => ("f64", elem_ty), _ => { return_error!( "unsupported element type `{}` of floating-point vector `{}`", f.name_str(), in_ty ); } } } else { return_error!("`{}` is not a floating-point type", in_ty); }; let vec_ty = bx.type_vector(elem_ty, in_len); let (intr_name, fn_ty) = match name { sym::simd_ceil => ("ceil", bx.type_func(&[vec_ty], vec_ty)), sym::simd_fabs => ("fabs", bx.type_func(&[vec_ty], vec_ty)), sym::simd_fcos => ("cos", bx.type_func(&[vec_ty], vec_ty)), sym::simd_fexp2 => ("exp2", bx.type_func(&[vec_ty], vec_ty)), sym::simd_fexp => ("exp", bx.type_func(&[vec_ty], vec_ty)), sym::simd_flog10 => ("log10", bx.type_func(&[vec_ty], vec_ty)), sym::simd_flog2 => ("log2", bx.type_func(&[vec_ty], vec_ty)), sym::simd_flog => ("log", bx.type_func(&[vec_ty], vec_ty)), sym::simd_floor => ("floor", bx.type_func(&[vec_ty], vec_ty)), sym::simd_fma => ("fma", bx.type_func(&[vec_ty, vec_ty, vec_ty], vec_ty)), sym::simd_fpowi => ("powi", bx.type_func(&[vec_ty, bx.type_i32()], vec_ty)), sym::simd_fpow => ("pow", bx.type_func(&[vec_ty, vec_ty], vec_ty)), sym::simd_fsin => ("sin", bx.type_func(&[vec_ty], vec_ty)), sym::simd_fsqrt => ("sqrt", bx.type_func(&[vec_ty], vec_ty)), sym::simd_round => ("round", bx.type_func(&[vec_ty], vec_ty)), sym::simd_trunc => ("trunc", bx.type_func(&[vec_ty], vec_ty)), _ => return_error!("unrecognized intrinsic `{}`", name), }; let llvm_name = &format!("llvm.{0}.v{1}{2}", intr_name, in_len, elem_ty_str); let f = bx.declare_cfn(llvm_name, llvm::UnnamedAddr::No, fn_ty); let c = bx.call( fn_ty, None, f, &args.iter().map(|arg| arg.immediate()).collect::>(), None, ); Ok(c) } if std::matches!( name, sym::simd_ceil | sym::simd_fabs | sym::simd_fcos | sym::simd_fexp2 | sym::simd_fexp | sym::simd_flog10 | sym::simd_flog2 | sym::simd_flog | sym::simd_floor | sym::simd_fma | sym::simd_fpow | sym::simd_fpowi | sym::simd_fsin | sym::simd_fsqrt | sym::simd_round | sym::simd_trunc ) { return simd_simple_float_intrinsic(name, in_elem, in_ty, in_len, bx, span, args); } // FIXME: use: // https://github.com/llvm-mirror/llvm/blob/master/include/llvm/IR/Function.h#L182 // https://github.com/llvm-mirror/llvm/blob/master/include/llvm/IR/Intrinsics.h#L81 fn llvm_vector_str( elem_ty: Ty<'_>, vec_len: u64, no_pointers: usize, bx: &Builder<'_, '_, '_>, ) -> String { let p0s: String = "p0".repeat(no_pointers); match *elem_ty.kind() { ty::Int(v) => format!( "v{}{}i{}", vec_len, p0s, // Normalize to prevent crash if v: IntTy::Isize v.normalize(bx.target_spec().pointer_width).bit_width().unwrap() ), ty::Uint(v) => format!( "v{}{}i{}", vec_len, p0s, // Normalize to prevent crash if v: UIntTy::Usize v.normalize(bx.target_spec().pointer_width).bit_width().unwrap() ), ty::Float(v) => format!("v{}{}f{}", vec_len, p0s, v.bit_width()), _ => unreachable!(), } } fn llvm_vector_ty<'ll>( cx: &CodegenCx<'ll, '_>, elem_ty: Ty<'_>, vec_len: u64, mut no_pointers: usize, ) -> &'ll Type { // FIXME: use cx.layout_of(ty).llvm_type() ? let mut elem_ty = match *elem_ty.kind() { ty::Int(v) => cx.type_int_from_ty(v), ty::Uint(v) => cx.type_uint_from_ty(v), ty::Float(v) => cx.type_float_from_ty(v), _ => unreachable!(), }; while no_pointers > 0 { elem_ty = cx.type_ptr_to(elem_ty); no_pointers -= 1; } cx.type_vector(elem_ty, vec_len) } if name == sym::simd_gather { // simd_gather(values: , pointers: , // mask: ) -> // * N: number of elements in the input vectors // * T: type of the element to load // * M: any integer width is supported, will be truncated to i1 // All types must be simd vector types require_simd!(in_ty, "first"); require_simd!(arg_tys[1], "second"); require_simd!(arg_tys[2], "third"); require_simd!(ret_ty, "return"); // Of the same length: let (out_len, _) = arg_tys[1].simd_size_and_type(bx.tcx()); let (out_len2, _) = arg_tys[2].simd_size_and_type(bx.tcx()); require!( in_len == out_len, "expected {} argument with length {} (same as input type `{}`), \ found `{}` with length {}", "second", in_len, in_ty, arg_tys[1], out_len ); require!( in_len == out_len2, "expected {} argument with length {} (same as input type `{}`), \ found `{}` with length {}", "third", in_len, in_ty, arg_tys[2], out_len2 ); // The return type must match the first argument type require!(ret_ty == in_ty, "expected return type `{}`, found `{}`", in_ty, ret_ty); // This counts how many pointers fn ptr_count(t: Ty<'_>) -> usize { match t.kind() { ty::RawPtr(p) => 1 + ptr_count(p.ty), _ => 0, } } // Non-ptr type fn non_ptr(t: Ty<'_>) -> Ty<'_> { match t.kind() { ty::RawPtr(p) => non_ptr(p.ty), _ => t, } } // The second argument must be a simd vector with an element type that's a pointer // to the element type of the first argument let (_, element_ty0) = arg_tys[0].simd_size_and_type(bx.tcx()); let (_, element_ty1) = arg_tys[1].simd_size_and_type(bx.tcx()); let (pointer_count, underlying_ty) = match element_ty1.kind() { ty::RawPtr(p) if p.ty == in_elem => (ptr_count(element_ty1), non_ptr(element_ty1)), _ => { require!( false, "expected element type `{}` of second argument `{}` \ to be a pointer to the element type `{}` of the first \ argument `{}`, found `{}` != `*_ {}`", element_ty1, arg_tys[1], in_elem, in_ty, element_ty1, in_elem ); unreachable!(); } }; assert!(pointer_count > 0); assert_eq!(pointer_count - 1, ptr_count(element_ty0)); assert_eq!(underlying_ty, non_ptr(element_ty0)); // The element type of the third argument must be a signed integer type of any width: let (_, element_ty2) = arg_tys[2].simd_size_and_type(bx.tcx()); match element_ty2.kind() { ty::Int(_) => (), _ => { require!( false, "expected element type `{}` of third argument `{}` \ to be a signed integer type", element_ty2, arg_tys[2] ); } } // Alignment of T, must be a constant integer value: let alignment_ty = bx.type_i32(); let alignment = bx.const_i32(bx.align_of(in_elem).bytes() as i32); // Truncate the mask vector to a vector of i1s: let (mask, mask_ty) = { let i1 = bx.type_i1(); let i1xn = bx.type_vector(i1, in_len); (bx.trunc(args[2].immediate(), i1xn), i1xn) }; // Type of the vector of pointers: let llvm_pointer_vec_ty = llvm_vector_ty(bx, underlying_ty, in_len, pointer_count); let llvm_pointer_vec_str = llvm_vector_str(underlying_ty, in_len, pointer_count, bx); // Type of the vector of elements: let llvm_elem_vec_ty = llvm_vector_ty(bx, underlying_ty, in_len, pointer_count - 1); let llvm_elem_vec_str = llvm_vector_str(underlying_ty, in_len, pointer_count - 1, bx); let llvm_intrinsic = format!("llvm.masked.gather.{}.{}", llvm_elem_vec_str, llvm_pointer_vec_str); let fn_ty = bx.type_func( &[llvm_pointer_vec_ty, alignment_ty, mask_ty, llvm_elem_vec_ty], llvm_elem_vec_ty, ); let f = bx.declare_cfn(&llvm_intrinsic, llvm::UnnamedAddr::No, fn_ty); let v = bx.call( fn_ty, None, f, &[args[1].immediate(), alignment, mask, args[0].immediate()], None, ); return Ok(v); } if name == sym::simd_scatter { // simd_scatter(values: , pointers: , // mask: ) -> () // * N: number of elements in the input vectors // * T: type of the element to load // * M: any integer width is supported, will be truncated to i1 // All types must be simd vector types require_simd!(in_ty, "first"); require_simd!(arg_tys[1], "second"); require_simd!(arg_tys[2], "third"); // Of the same length: let (element_len1, _) = arg_tys[1].simd_size_and_type(bx.tcx()); let (element_len2, _) = arg_tys[2].simd_size_and_type(bx.tcx()); require!( in_len == element_len1, "expected {} argument with length {} (same as input type `{}`), \ found `{}` with length {}", "second", in_len, in_ty, arg_tys[1], element_len1 ); require!( in_len == element_len2, "expected {} argument with length {} (same as input type `{}`), \ found `{}` with length {}", "third", in_len, in_ty, arg_tys[2], element_len2 ); // This counts how many pointers fn ptr_count(t: Ty<'_>) -> usize { match t.kind() { ty::RawPtr(p) => 1 + ptr_count(p.ty), _ => 0, } } // Non-ptr type fn non_ptr(t: Ty<'_>) -> Ty<'_> { match t.kind() { ty::RawPtr(p) => non_ptr(p.ty), _ => t, } } // The second argument must be a simd vector with an element type that's a pointer // to the element type of the first argument let (_, element_ty0) = arg_tys[0].simd_size_and_type(bx.tcx()); let (_, element_ty1) = arg_tys[1].simd_size_and_type(bx.tcx()); let (_, element_ty2) = arg_tys[2].simd_size_and_type(bx.tcx()); let (pointer_count, underlying_ty) = match element_ty1.kind() { ty::RawPtr(p) if p.ty == in_elem && p.mutbl.is_mut() => { (ptr_count(element_ty1), non_ptr(element_ty1)) } _ => { require!( false, "expected element type `{}` of second argument `{}` \ to be a pointer to the element type `{}` of the first \ argument `{}`, found `{}` != `*mut {}`", element_ty1, arg_tys[1], in_elem, in_ty, element_ty1, in_elem ); unreachable!(); } }; assert!(pointer_count > 0); assert_eq!(pointer_count - 1, ptr_count(element_ty0)); assert_eq!(underlying_ty, non_ptr(element_ty0)); // The element type of the third argument must be a signed integer type of any width: match element_ty2.kind() { ty::Int(_) => (), _ => { require!( false, "expected element type `{}` of third argument `{}` \ be a signed integer type", element_ty2, arg_tys[2] ); } } // Alignment of T, must be a constant integer value: let alignment_ty = bx.type_i32(); let alignment = bx.const_i32(bx.align_of(in_elem).bytes() as i32); // Truncate the mask vector to a vector of i1s: let (mask, mask_ty) = { let i1 = bx.type_i1(); let i1xn = bx.type_vector(i1, in_len); (bx.trunc(args[2].immediate(), i1xn), i1xn) }; let ret_t = bx.type_void(); // Type of the vector of pointers: let llvm_pointer_vec_ty = llvm_vector_ty(bx, underlying_ty, in_len, pointer_count); let llvm_pointer_vec_str = llvm_vector_str(underlying_ty, in_len, pointer_count, bx); // Type of the vector of elements: let llvm_elem_vec_ty = llvm_vector_ty(bx, underlying_ty, in_len, pointer_count - 1); let llvm_elem_vec_str = llvm_vector_str(underlying_ty, in_len, pointer_count - 1, bx); let llvm_intrinsic = format!("llvm.masked.scatter.{}.{}", llvm_elem_vec_str, llvm_pointer_vec_str); let fn_ty = bx.type_func(&[llvm_elem_vec_ty, llvm_pointer_vec_ty, alignment_ty, mask_ty], ret_t); let f = bx.declare_cfn(&llvm_intrinsic, llvm::UnnamedAddr::No, fn_ty); let v = bx.call( fn_ty, None, f, &[args[0].immediate(), args[1].immediate(), alignment, mask], None, ); return Ok(v); } macro_rules! arith_red { ($name:ident : $integer_reduce:ident, $float_reduce:ident, $ordered:expr, $op:ident, $identity:expr) => { if name == sym::$name { require!( ret_ty == in_elem, "expected return type `{}` (element of input `{}`), found `{}`", in_elem, in_ty, ret_ty ); return match in_elem.kind() { ty::Int(_) | ty::Uint(_) => { let r = bx.$integer_reduce(args[0].immediate()); if $ordered { // if overflow occurs, the result is the // mathematical result modulo 2^n: Ok(bx.$op(args[1].immediate(), r)) } else { Ok(bx.$integer_reduce(args[0].immediate())) } } ty::Float(f) => { let acc = if $ordered { // ordered arithmetic reductions take an accumulator args[1].immediate() } else { // unordered arithmetic reductions use the identity accumulator match f.bit_width() { 32 => bx.const_real(bx.type_f32(), $identity), 64 => bx.const_real(bx.type_f64(), $identity), v => return_error!( r#" unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#, sym::$name, in_ty, in_elem, v, ret_ty ), } }; Ok(bx.$float_reduce(acc, args[0].immediate())) } _ => return_error!( "unsupported {} from `{}` with element `{}` to `{}`", sym::$name, in_ty, in_elem, ret_ty ), }; } }; } arith_red!(simd_reduce_add_ordered: vector_reduce_add, vector_reduce_fadd, true, add, 0.0); arith_red!(simd_reduce_mul_ordered: vector_reduce_mul, vector_reduce_fmul, true, mul, 1.0); arith_red!( simd_reduce_add_unordered: vector_reduce_add, vector_reduce_fadd_fast, false, add, 0.0 ); arith_red!( simd_reduce_mul_unordered: vector_reduce_mul, vector_reduce_fmul_fast, false, mul, 1.0 ); macro_rules! minmax_red { ($name:ident: $int_red:ident, $float_red:ident) => { if name == sym::$name { require!( ret_ty == in_elem, "expected return type `{}` (element of input `{}`), found `{}`", in_elem, in_ty, ret_ty ); return match in_elem.kind() { ty::Int(_i) => Ok(bx.$int_red(args[0].immediate(), true)), ty::Uint(_u) => Ok(bx.$int_red(args[0].immediate(), false)), ty::Float(_f) => Ok(bx.$float_red(args[0].immediate())), _ => return_error!( "unsupported {} from `{}` with element `{}` to `{}`", sym::$name, in_ty, in_elem, ret_ty ), }; } }; } minmax_red!(simd_reduce_min: vector_reduce_min, vector_reduce_fmin); minmax_red!(simd_reduce_max: vector_reduce_max, vector_reduce_fmax); minmax_red!(simd_reduce_min_nanless: vector_reduce_min, vector_reduce_fmin_fast); minmax_red!(simd_reduce_max_nanless: vector_reduce_max, vector_reduce_fmax_fast); macro_rules! bitwise_red { ($name:ident : $red:ident, $boolean:expr) => { if name == sym::$name { let input = if !$boolean { require!( ret_ty == in_elem, "expected return type `{}` (element of input `{}`), found `{}`", in_elem, in_ty, ret_ty ); args[0].immediate() } else { match in_elem.kind() { ty::Int(_) | ty::Uint(_) => {} _ => return_error!( "unsupported {} from `{}` with element `{}` to `{}`", sym::$name, in_ty, in_elem, ret_ty ), } // boolean reductions operate on vectors of i1s: let i1 = bx.type_i1(); let i1xn = bx.type_vector(i1, in_len as u64); bx.trunc(args[0].immediate(), i1xn) }; return match in_elem.kind() { ty::Int(_) | ty::Uint(_) => { let r = bx.$red(input); Ok(if !$boolean { r } else { bx.zext(r, bx.type_bool()) }) } _ => return_error!( "unsupported {} from `{}` with element `{}` to `{}`", sym::$name, in_ty, in_elem, ret_ty ), }; } }; } bitwise_red!(simd_reduce_and: vector_reduce_and, false); bitwise_red!(simd_reduce_or: vector_reduce_or, false); bitwise_red!(simd_reduce_xor: vector_reduce_xor, false); bitwise_red!(simd_reduce_all: vector_reduce_and, true); bitwise_red!(simd_reduce_any: vector_reduce_or, true); if name == sym::simd_cast_ptr { require_simd!(ret_ty, "return"); let (out_len, out_elem) = ret_ty.simd_size_and_type(bx.tcx()); require!( in_len == out_len, "expected return type with length {} (same as input type `{}`), \ found `{}` with length {}", in_len, in_ty, ret_ty, out_len ); match in_elem.kind() { ty::RawPtr(p) => { let (metadata, check_sized) = p.ty.ptr_metadata_ty(bx.tcx, |ty| { bx.tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), ty) }); assert!(!check_sized); // we are in codegen, so we shouldn't see these types require!(metadata.is_unit(), "cannot cast fat pointer `{}`", in_elem) } _ => return_error!("expected pointer, got `{}`", in_elem), } match out_elem.kind() { ty::RawPtr(p) => { let (metadata, check_sized) = p.ty.ptr_metadata_ty(bx.tcx, |ty| { bx.tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), ty) }); assert!(!check_sized); // we are in codegen, so we shouldn't see these types require!(metadata.is_unit(), "cannot cast to fat pointer `{}`", out_elem) } _ => return_error!("expected pointer, got `{}`", out_elem), } if in_elem == out_elem { return Ok(args[0].immediate()); } else { return Ok(bx.pointercast(args[0].immediate(), llret_ty)); } } if name == sym::simd_expose_addr { require_simd!(ret_ty, "return"); let (out_len, out_elem) = ret_ty.simd_size_and_type(bx.tcx()); require!( in_len == out_len, "expected return type with length {} (same as input type `{}`), \ found `{}` with length {}", in_len, in_ty, ret_ty, out_len ); match in_elem.kind() { ty::RawPtr(_) => {} _ => return_error!("expected pointer, got `{}`", in_elem), } match out_elem.kind() { ty::Uint(ty::UintTy::Usize) => {} _ => return_error!("expected `usize`, got `{}`", out_elem), } return Ok(bx.ptrtoint(args[0].immediate(), llret_ty)); } if name == sym::simd_from_exposed_addr { require_simd!(ret_ty, "return"); let (out_len, out_elem) = ret_ty.simd_size_and_type(bx.tcx()); require!( in_len == out_len, "expected return type with length {} (same as input type `{}`), \ found `{}` with length {}", in_len, in_ty, ret_ty, out_len ); match in_elem.kind() { ty::Uint(ty::UintTy::Usize) => {} _ => return_error!("expected `usize`, got `{}`", in_elem), } match out_elem.kind() { ty::RawPtr(_) => {} _ => return_error!("expected pointer, got `{}`", out_elem), } return Ok(bx.inttoptr(args[0].immediate(), llret_ty)); } if name == sym::simd_cast || name == sym::simd_as { require_simd!(ret_ty, "return"); let (out_len, out_elem) = ret_ty.simd_size_and_type(bx.tcx()); require!( in_len == out_len, "expected return type with length {} (same as input type `{}`), \ found `{}` with length {}", in_len, in_ty, ret_ty, out_len ); // casting cares about nominal type, not just structural type if in_elem == out_elem { return Ok(args[0].immediate()); } enum Style { Float, Int(/* is signed? */ bool), Unsupported, } let (in_style, in_width) = match in_elem.kind() { // vectors of pointer-sized integers should've been // disallowed before here, so this unwrap is safe. ty::Int(i) => ( Style::Int(true), i.normalize(bx.tcx().sess.target.pointer_width).bit_width().unwrap(), ), ty::Uint(u) => ( Style::Int(false), u.normalize(bx.tcx().sess.target.pointer_width).bit_width().unwrap(), ), ty::Float(f) => (Style::Float, f.bit_width()), _ => (Style::Unsupported, 0), }; let (out_style, out_width) = match out_elem.kind() { ty::Int(i) => ( Style::Int(true), i.normalize(bx.tcx().sess.target.pointer_width).bit_width().unwrap(), ), ty::Uint(u) => ( Style::Int(false), u.normalize(bx.tcx().sess.target.pointer_width).bit_width().unwrap(), ), ty::Float(f) => (Style::Float, f.bit_width()), _ => (Style::Unsupported, 0), }; match (in_style, out_style) { (Style::Int(in_is_signed), Style::Int(_)) => { return Ok(match in_width.cmp(&out_width) { Ordering::Greater => bx.trunc(args[0].immediate(), llret_ty), Ordering::Equal => args[0].immediate(), Ordering::Less => { if in_is_signed { bx.sext(args[0].immediate(), llret_ty) } else { bx.zext(args[0].immediate(), llret_ty) } } }); } (Style::Int(in_is_signed), Style::Float) => { return Ok(if in_is_signed { bx.sitofp(args[0].immediate(), llret_ty) } else { bx.uitofp(args[0].immediate(), llret_ty) }); } (Style::Float, Style::Int(out_is_signed)) => { return Ok(match (out_is_signed, name == sym::simd_as) { (false, false) => bx.fptoui(args[0].immediate(), llret_ty), (true, false) => bx.fptosi(args[0].immediate(), llret_ty), (_, true) => bx.cast_float_to_int(out_is_signed, args[0].immediate(), llret_ty), }); } (Style::Float, Style::Float) => { return Ok(match in_width.cmp(&out_width) { Ordering::Greater => bx.fptrunc(args[0].immediate(), llret_ty), Ordering::Equal => args[0].immediate(), Ordering::Less => bx.fpext(args[0].immediate(), llret_ty), }); } _ => { /* Unsupported. Fallthrough. */ } } require!( false, "unsupported cast from `{}` with element `{}` to `{}` with element `{}`", in_ty, in_elem, ret_ty, out_elem ); } macro_rules! arith_binary { ($($name: ident: $($($p: ident),* => $call: ident),*;)*) => { $(if name == sym::$name { match in_elem.kind() { $($(ty::$p(_))|* => { return Ok(bx.$call(args[0].immediate(), args[1].immediate())) })* _ => {}, } require!(false, "unsupported operation on `{}` with element `{}`", in_ty, in_elem) })* } } arith_binary! { simd_add: Uint, Int => add, Float => fadd; simd_sub: Uint, Int => sub, Float => fsub; simd_mul: Uint, Int => mul, Float => fmul; simd_div: Uint => udiv, Int => sdiv, Float => fdiv; simd_rem: Uint => urem, Int => srem, Float => frem; simd_shl: Uint, Int => shl; simd_shr: Uint => lshr, Int => ashr; simd_and: Uint, Int => and; simd_or: Uint, Int => or; simd_xor: Uint, Int => xor; simd_fmax: Float => maxnum; simd_fmin: Float => minnum; } macro_rules! arith_unary { ($($name: ident: $($($p: ident),* => $call: ident),*;)*) => { $(if name == sym::$name { match in_elem.kind() { $($(ty::$p(_))|* => { return Ok(bx.$call(args[0].immediate())) })* _ => {}, } require!(false, "unsupported operation on `{}` with element `{}`", in_ty, in_elem) })* } } arith_unary! { simd_neg: Int => neg, Float => fneg; } if name == sym::simd_arith_offset { // This also checks that the first operand is a ptr type. let pointee = in_elem.builtin_deref(true).unwrap_or_else(|| { span_bug!(span, "must be called with a vector of pointer types as first argument") }); let layout = bx.layout_of(pointee.ty); let ptrs = args[0].immediate(); // The second argument must be a ptr-sized integer. // (We don't care about the signedness, this is wrapping anyway.) let (_offsets_len, offsets_elem) = arg_tys[1].simd_size_and_type(bx.tcx()); if !matches!(offsets_elem.kind(), ty::Int(ty::IntTy::Isize) | ty::Uint(ty::UintTy::Usize)) { span_bug!( span, "must be called with a vector of pointer-sized integers as second argument" ); } let offsets = args[1].immediate(); return Ok(bx.gep(bx.backend_type(layout), ptrs, &[offsets])); } if name == sym::simd_saturating_add || name == sym::simd_saturating_sub { let lhs = args[0].immediate(); let rhs = args[1].immediate(); let is_add = name == sym::simd_saturating_add; let ptr_bits = bx.tcx().data_layout.pointer_size.bits() as _; let (signed, elem_width, elem_ty) = match *in_elem.kind() { ty::Int(i) => (true, i.bit_width().unwrap_or(ptr_bits), bx.cx.type_int_from_ty(i)), ty::Uint(i) => (false, i.bit_width().unwrap_or(ptr_bits), bx.cx.type_uint_from_ty(i)), _ => { return_error!( "expected element type `{}` of vector type `{}` \ to be a signed or unsigned integer type", arg_tys[0].simd_size_and_type(bx.tcx()).1, arg_tys[0] ); } }; let llvm_intrinsic = &format!( "llvm.{}{}.sat.v{}i{}", if signed { 's' } else { 'u' }, if is_add { "add" } else { "sub" }, in_len, elem_width ); let vec_ty = bx.cx.type_vector(elem_ty, in_len as u64); let fn_ty = bx.type_func(&[vec_ty, vec_ty], vec_ty); let f = bx.declare_cfn(llvm_intrinsic, llvm::UnnamedAddr::No, fn_ty); let v = bx.call(fn_ty, None, f, &[lhs, rhs], None); return Ok(v); } span_bug!(span, "unknown SIMD intrinsic"); } // Returns the width of an int Ty, and if it's signed or not // Returns None if the type is not an integer // FIXME: there’s multiple of this functions, investigate using some of the already existing // stuffs. fn int_type_width_signed(ty: Ty<'_>, cx: &CodegenCx<'_, '_>) -> Option<(u64, bool)> { match ty.kind() { ty::Int(t) => { Some((t.bit_width().unwrap_or(u64::from(cx.tcx.sess.target.pointer_width)), true)) } ty::Uint(t) => { Some((t.bit_width().unwrap_or(u64::from(cx.tcx.sess.target.pointer_width)), false)) } _ => None, } }