| pub mod llvm; |
| mod simd; |
| |
| use gccjit::{ComparisonOp, Function, RValue, ToRValue, Type, UnaryOp, FunctionType}; |
| use rustc_codegen_ssa::MemFlags; |
| use rustc_codegen_ssa::base::wants_msvc_seh; |
| use rustc_codegen_ssa::common::IntPredicate; |
| use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue}; |
| use rustc_codegen_ssa::mir::place::PlaceRef; |
| use rustc_codegen_ssa::traits::{ArgAbiMethods, BaseTypeMethods, BuilderMethods, ConstMethods, IntrinsicCallMethods}; |
| use rustc_middle::bug; |
| use rustc_middle::ty::{self, Instance, Ty}; |
| use rustc_middle::ty::layout::LayoutOf; |
| use rustc_span::{Span, Symbol, symbol::kw, sym}; |
| use rustc_target::abi::HasDataLayout; |
| use rustc_target::abi::call::{ArgAbi, FnAbi, PassMode}; |
| use rustc_target::spec::PanicStrategy; |
| |
| use crate::abi::GccType; |
| use crate::builder::Builder; |
| use crate::common::{SignType, TypeReflection}; |
| use crate::context::CodegenCx; |
| use crate::errors::InvalidMonomorphizationBasicInteger; |
| use crate::type_of::LayoutGccExt; |
| use crate::intrinsic::simd::generic_simd_intrinsic; |
| |
| fn get_simple_intrinsic<'gcc, 'tcx>(cx: &CodegenCx<'gcc, 'tcx>, name: Symbol) -> Option<Function<'gcc>> { |
| let gcc_name = match name { |
| sym::sqrtf32 => "sqrtf", |
| sym::sqrtf64 => "sqrt", |
| sym::powif32 => "__builtin_powif", |
| sym::powif64 => "__builtin_powi", |
| sym::sinf32 => "sinf", |
| sym::sinf64 => "sin", |
| sym::cosf32 => "cosf", |
| sym::cosf64 => "cos", |
| sym::powf32 => "powf", |
| sym::powf64 => "pow", |
| sym::expf32 => "expf", |
| sym::expf64 => "exp", |
| sym::exp2f32 => "exp2f", |
| sym::exp2f64 => "exp2", |
| sym::logf32 => "logf", |
| sym::logf64 => "log", |
| sym::log10f32 => "log10f", |
| sym::log10f64 => "log10", |
| sym::log2f32 => "log2f", |
| sym::log2f64 => "log2", |
| sym::fmaf32 => "fmaf", |
| sym::fmaf64 => "fma", |
| sym::fabsf32 => "fabsf", |
| sym::fabsf64 => "fabs", |
| sym::minnumf32 => "fminf", |
| sym::minnumf64 => "fmin", |
| sym::maxnumf32 => "fmaxf", |
| sym::maxnumf64 => "fmax", |
| sym::copysignf32 => "copysignf", |
| sym::copysignf64 => "copysign", |
| sym::floorf32 => "floorf", |
| sym::floorf64 => "floor", |
| sym::ceilf32 => "ceilf", |
| sym::ceilf64 => "ceil", |
| sym::truncf32 => "truncf", |
| sym::truncf64 => "trunc", |
| sym::rintf32 => "rintf", |
| sym::rintf64 => "rint", |
| sym::nearbyintf32 => "nearbyintf", |
| sym::nearbyintf64 => "nearbyint", |
| sym::roundf32 => "roundf", |
| sym::roundf64 => "round", |
| sym::abort => "abort", |
| _ => return None, |
| }; |
| Some(cx.context.get_builtin_function(&gcc_name)) |
| } |
| |
| impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> { |
| fn codegen_intrinsic_call(&mut self, instance: Instance<'tcx>, fn_abi: &FnAbi<'tcx, Ty<'tcx>>, args: &[OperandRef<'tcx, RValue<'gcc>>], llresult: RValue<'gcc>, span: Span) { |
| let tcx = self.tcx; |
| let callee_ty = instance.ty(tcx, ty::ParamEnv::reveal_all()); |
| |
| let (def_id, substs) = match *callee_ty.kind() { |
| ty::FnDef(def_id, substs) => (def_id, substs), |
| _ => 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 name_str = name.as_str(); |
| |
| let llret_ty = self.layout_of(ret_ty).gcc_type(self, true); |
| 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() => { |
| // FIXME(antoyo): remove this cast when the API supports function. |
| let func = unsafe { std::mem::transmute(simple.expect("simple")) }; |
| self.call(self.type_void(), None, func, &args.iter().map(|arg| arg.immediate()).collect::<Vec<_>>(), None) |
| }, |
| sym::likely => { |
| self.expect(args[0].immediate(), true) |
| } |
| sym::unlikely => { |
| self.expect(args[0].immediate(), false) |
| } |
| kw::Try => { |
| try_intrinsic( |
| self, |
| args[0].immediate(), |
| args[1].immediate(), |
| args[2].immediate(), |
| llresult, |
| ); |
| return; |
| } |
| sym::breakpoint => { |
| unimplemented!(); |
| } |
| sym::va_copy => { |
| unimplemented!(); |
| } |
| sym::va_arg => { |
| unimplemented!(); |
| } |
| |
| sym::volatile_load | sym::unaligned_volatile_load => { |
| let tp_ty = substs.type_at(0); |
| let mut ptr = args[0].immediate(); |
| if let PassMode::Cast(ty, _) = &fn_abi.ret.mode { |
| ptr = self.pointercast(ptr, self.type_ptr_to(ty.gcc_type(self))); |
| } |
| let load = self.volatile_load(ptr.get_type(), ptr); |
| // TODO(antoyo): set alignment. |
| 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 => { |
| unimplemented!(); |
| } |
| 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 func = self.current_func.borrow().expect("func"); |
| let then_block = func.new_block("then"); |
| let else_block = func.new_block("else"); |
| let after_block = func.new_block("after"); |
| |
| let arg = args[0].immediate(); |
| let result = func.new_local(None, arg.get_type(), "zeros"); |
| let zero = self.cx.gcc_zero(arg.get_type()); |
| let cond = self.gcc_icmp(IntPredicate::IntEQ, arg, zero); |
| self.llbb().end_with_conditional(None, cond, then_block, else_block); |
| |
| let zero_result = self.cx.gcc_uint(arg.get_type(), width); |
| then_block.add_assignment(None, result, zero_result); |
| then_block.end_with_jump(None, after_block); |
| |
| // NOTE: since jumps were added in a place |
| // count_leading_zeroes() does not expect, the current block |
| // in the state need to be updated. |
| self.switch_to_block(else_block); |
| |
| let zeros = |
| match name { |
| sym::ctlz => self.count_leading_zeroes(width, arg), |
| sym::cttz => self.count_trailing_zeroes(width, arg), |
| _ => unreachable!(), |
| }; |
| self.llbb().add_assignment(None, result, zeros); |
| self.llbb().end_with_jump(None, after_block); |
| |
| // NOTE: since jumps were added in a place rustc does not |
| // expect, the current block in the state need to be updated. |
| self.switch_to_block(after_block); |
| |
| result.to_rvalue() |
| } |
| sym::ctlz_nonzero => { |
| self.count_leading_zeroes(width, args[0].immediate()) |
| }, |
| sym::cttz_nonzero => { |
| self.count_trailing_zeroes(width, args[0].immediate()) |
| } |
| sym::ctpop => self.pop_count(args[0].immediate()), |
| sym::bswap => { |
| if width == 8 { |
| args[0].immediate() // byte swap a u8/i8 is just a no-op |
| } |
| else { |
| self.gcc_bswap(args[0].immediate(), width) |
| } |
| }, |
| sym::bitreverse => self.bit_reverse(width, args[0].immediate()), |
| sym::rotate_left | sym::rotate_right => { |
| // TODO(antoyo): implement using algorithm from: |
| // https://blog.regehr.org/archives/1063 |
| // for other platforms. |
| let is_left = name == sym::rotate_left; |
| let val = args[0].immediate(); |
| let raw_shift = args[1].immediate(); |
| if is_left { |
| self.rotate_left(val, raw_shift, width) |
| } |
| else { |
| self.rotate_right(val, raw_shift, width) |
| } |
| }, |
| sym::saturating_add => { |
| self.saturating_add(args[0].immediate(), args[1].immediate(), signed, width) |
| }, |
| sym::saturating_sub => { |
| self.saturating_sub(args[0].immediate(), args[1].immediate(), signed, width) |
| }, |
| _ => bug!(), |
| }, |
| None => { |
| tcx.sess.emit_err(InvalidMonomorphizationBasicInteger { span, name, ty }); |
| return; |
| } |
| } |
| } |
| |
| sym::raw_eq => { |
| use rustc_target::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()); // FIXME(antoyo): LLVM creates an integer of 96 bits for [i32; 3], but gcc doesn't support this, so it creates an integer of 128 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 void_ptr_type = self.context.new_type::<*const ()>(); |
| let a_ptr = self.bitcast(a, void_ptr_type); |
| let b_ptr = self.bitcast(b, void_ptr_type); |
| let n = self.context.new_cast(None, self.const_usize(layout.size().bytes()), self.sizet_type); |
| let builtin = self.context.get_builtin_function("memcmp"); |
| let cmp = self.context.new_call(None, builtin, &[a_ptr, b_ptr, n]); |
| self.icmp(IntPredicate::IntEQ, cmp, self.const_i32(0)) |
| } |
| } |
| |
| sym::black_box => { |
| args[0].val.store(self, result); |
| |
| let block = self.llbb(); |
| let extended_asm = block.add_extended_asm(None, ""); |
| extended_asm.add_input_operand(None, "r", result.llval); |
| extended_asm.add_clobber("memory"); |
| extended_asm.set_volatile_flag(true); |
| |
| // We have copied the value to `result` already. |
| return; |
| } |
| |
| sym::ptr_mask => { |
| let usize_type = self.context.new_type::<usize>(); |
| let void_ptr_type = self.context.new_type::<*const ()>(); |
| |
| let ptr = args[0].immediate(); |
| let mask = args[1].immediate(); |
| |
| let addr = self.bitcast(ptr, usize_type); |
| let masked = self.and(addr, mask); |
| self.bitcast(masked, void_ptr_type) |
| }, |
| |
| _ if name_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.gcc_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) { |
| let func = self.context.get_builtin_function("abort"); |
| let func: RValue<'gcc> = unsafe { std::mem::transmute(func) }; |
| self.call(self.type_void(), None, func, &[], None); |
| } |
| |
| fn assume(&mut self, value: Self::Value) { |
| // TODO(antoyo): switch to assume when it exists. |
| // Or use something like this: |
| // #define __assume(cond) do { if (!(cond)) __builtin_unreachable(); } while (0) |
| self.expect(value, true); |
| } |
| |
| fn expect(&mut self, cond: Self::Value, _expected: bool) -> Self::Value { |
| // TODO(antoyo) |
| cond |
| } |
| |
| fn type_test(&mut self, _pointer: Self::Value, _typeid: Self::Value) -> Self::Value { |
| // Unsupported. |
| self.context.new_rvalue_from_int(self.int_type, 0) |
| } |
| |
| fn type_checked_load( |
| &mut self, |
| _llvtable: Self::Value, |
| _vtable_byte_offset: u64, |
| _typeid: Self::Value, |
| ) -> Self::Value { |
| // Unsupported. |
| self.context.new_rvalue_from_int(self.int_type, 0) |
| } |
| |
| fn va_start(&mut self, _va_list: RValue<'gcc>) -> RValue<'gcc> { |
| unimplemented!(); |
| } |
| |
| fn va_end(&mut self, _va_list: RValue<'gcc>) -> RValue<'gcc> { |
| unimplemented!(); |
| } |
| } |
| |
| impl<'a, 'gcc, 'tcx> ArgAbiMethods<'tcx> for Builder<'a, 'gcc, 'tcx> { |
| fn store_fn_arg(&mut self, arg_abi: &ArgAbi<'tcx, Ty<'tcx>>, idx: &mut usize, dst: PlaceRef<'tcx, Self::Value>) { |
| arg_abi.store_fn_arg(self, idx, dst) |
| } |
| |
| fn store_arg(&mut self, arg_abi: &ArgAbi<'tcx, Ty<'tcx>>, val: RValue<'gcc>, dst: PlaceRef<'tcx, RValue<'gcc>>) { |
| arg_abi.store(self, val, dst) |
| } |
| |
| fn arg_memory_ty(&self, arg_abi: &ArgAbi<'tcx, Ty<'tcx>>) -> Type<'gcc> { |
| arg_abi.memory_ty(self) |
| } |
| } |
| |
| pub trait ArgAbiExt<'gcc, 'tcx> { |
| fn memory_ty(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc>; |
| fn store(&self, bx: &mut Builder<'_, 'gcc, 'tcx>, val: RValue<'gcc>, dst: PlaceRef<'tcx, RValue<'gcc>>); |
| fn store_fn_arg(&self, bx: &mut Builder<'_, 'gcc, 'tcx>, idx: &mut usize, dst: PlaceRef<'tcx, RValue<'gcc>>); |
| } |
| |
| impl<'gcc, 'tcx> ArgAbiExt<'gcc, 'tcx> for ArgAbi<'tcx, Ty<'tcx>> { |
| /// Gets the LLVM type for a place of the original Rust type of |
| /// this argument/return, i.e., the result of `type_of::type_of`. |
| fn memory_ty(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc> { |
| self.layout.gcc_type(cx, true) |
| } |
| |
| /// Stores a direct/indirect value described by this ArgAbi into a |
| /// place for the original Rust type of this argument/return. |
| /// Can be used for both storing formal arguments into Rust variables |
| /// or results of call/invoke instructions into their destinations. |
| fn store(&self, bx: &mut Builder<'_, 'gcc, 'tcx>, val: RValue<'gcc>, dst: PlaceRef<'tcx, RValue<'gcc>>) { |
| if self.is_ignore() { |
| return; |
| } |
| if self.is_sized_indirect() { |
| OperandValue::Ref(val, None, self.layout.align.abi).store(bx, dst) |
| } |
| else if self.is_unsized_indirect() { |
| bug!("unsized `ArgAbi` must be handled through `store_fn_arg`"); |
| } |
| else if let PassMode::Cast(ref cast, _) = self.mode { |
| // FIXME(eddyb): Figure out when the simpler Store is safe, clang |
| // uses it for i16 -> {i8, i8}, but not for i24 -> {i8, i8, i8}. |
| let can_store_through_cast_ptr = false; |
| if can_store_through_cast_ptr { |
| let cast_ptr_llty = bx.type_ptr_to(cast.gcc_type(bx)); |
| let cast_dst = bx.pointercast(dst.llval, cast_ptr_llty); |
| bx.store(val, cast_dst, self.layout.align.abi); |
| } |
| else { |
| // The actual return type is a struct, but the ABI |
| // adaptation code has cast it into some scalar type. The |
| // code that follows is the only reliable way I have |
| // found to do a transform like i64 -> {i32,i32}. |
| // Basically we dump the data onto the stack then memcpy it. |
| // |
| // Other approaches I tried: |
| // - Casting rust ret pointer to the foreign type and using Store |
| // is (a) unsafe if size of foreign type > size of rust type and |
| // (b) runs afoul of strict aliasing rules, yielding invalid |
| // assembly under -O (specifically, the store gets removed). |
| // - Truncating foreign type to correct integral type and then |
| // bitcasting to the struct type yields invalid cast errors. |
| |
| // We instead thus allocate some scratch space... |
| let scratch_size = cast.size(bx); |
| let scratch_align = cast.align(bx); |
| let llscratch = bx.alloca(cast.gcc_type(bx), scratch_align); |
| bx.lifetime_start(llscratch, scratch_size); |
| |
| // ... where we first store the value... |
| bx.store(val, llscratch, scratch_align); |
| |
| // ... and then memcpy it to the intended destination. |
| bx.memcpy( |
| dst.llval, |
| self.layout.align.abi, |
| llscratch, |
| scratch_align, |
| bx.const_usize(self.layout.size.bytes()), |
| MemFlags::empty(), |
| ); |
| |
| bx.lifetime_end(llscratch, scratch_size); |
| } |
| } |
| else { |
| OperandValue::Immediate(val).store(bx, dst); |
| } |
| } |
| |
| fn store_fn_arg<'a>(&self, bx: &mut Builder<'a, 'gcc, 'tcx>, idx: &mut usize, dst: PlaceRef<'tcx, RValue<'gcc>>) { |
| let mut next = || { |
| let val = bx.current_func().get_param(*idx as i32); |
| *idx += 1; |
| val.to_rvalue() |
| }; |
| match self.mode { |
| PassMode::Ignore => {}, |
| PassMode::Pair(..) => { |
| OperandValue::Pair(next(), next()).store(bx, dst); |
| }, |
| PassMode::Indirect { extra_attrs: Some(_), .. } => { |
| OperandValue::Ref(next(), Some(next()), self.layout.align.abi).store(bx, dst); |
| }, |
| PassMode::Direct(_) | PassMode::Indirect { extra_attrs: None, .. } | PassMode::Cast(..) => { |
| let next_arg = next(); |
| self.store(bx, next_arg, dst); |
| }, |
| } |
| } |
| } |
| |
| fn int_type_width_signed<'gcc, 'tcx>(ty: Ty<'tcx>, cx: &CodegenCx<'gcc, 'tcx>) -> Option<(u64, bool)> { |
| match ty.kind() { |
| ty::Int(t) => Some(( |
| match t { |
| rustc_middle::ty::IntTy::Isize => u64::from(cx.tcx.sess.target.pointer_width), |
| rustc_middle::ty::IntTy::I8 => 8, |
| rustc_middle::ty::IntTy::I16 => 16, |
| rustc_middle::ty::IntTy::I32 => 32, |
| rustc_middle::ty::IntTy::I64 => 64, |
| rustc_middle::ty::IntTy::I128 => 128, |
| }, |
| true, |
| )), |
| ty::Uint(t) => Some(( |
| match t { |
| rustc_middle::ty::UintTy::Usize => u64::from(cx.tcx.sess.target.pointer_width), |
| rustc_middle::ty::UintTy::U8 => 8, |
| rustc_middle::ty::UintTy::U16 => 16, |
| rustc_middle::ty::UintTy::U32 => 32, |
| rustc_middle::ty::UintTy::U64 => 64, |
| rustc_middle::ty::UintTy::U128 => 128, |
| }, |
| false, |
| )), |
| _ => None, |
| } |
| } |
| |
| impl<'a, 'gcc, 'tcx> Builder<'a, 'gcc, 'tcx> { |
| fn bit_reverse(&mut self, width: u64, value: RValue<'gcc>) -> RValue<'gcc> { |
| let result_type = value.get_type(); |
| let typ = result_type.to_unsigned(self.cx); |
| |
| let value = |
| if result_type.is_signed(self.cx) { |
| self.gcc_int_cast(value, typ) |
| } |
| else { |
| value |
| }; |
| |
| let context = &self.cx.context; |
| let result = |
| match width { |
| 8 => { |
| // First step. |
| let left = self.and(value, context.new_rvalue_from_int(typ, 0xF0)); |
| let left = self.lshr(left, context.new_rvalue_from_int(typ, 4)); |
| let right = self.and(value, context.new_rvalue_from_int(typ, 0x0F)); |
| let right = self.shl(right, context.new_rvalue_from_int(typ, 4)); |
| let step1 = self.or(left, right); |
| |
| // Second step. |
| let left = self.and(step1, context.new_rvalue_from_int(typ, 0xCC)); |
| let left = self.lshr(left, context.new_rvalue_from_int(typ, 2)); |
| let right = self.and(step1, context.new_rvalue_from_int(typ, 0x33)); |
| let right = self.shl(right, context.new_rvalue_from_int(typ, 2)); |
| let step2 = self.or(left, right); |
| |
| // Third step. |
| let left = self.and(step2, context.new_rvalue_from_int(typ, 0xAA)); |
| let left = self.lshr(left, context.new_rvalue_from_int(typ, 1)); |
| let right = self.and(step2, context.new_rvalue_from_int(typ, 0x55)); |
| let right = self.shl(right, context.new_rvalue_from_int(typ, 1)); |
| let step3 = self.or(left, right); |
| |
| step3 |
| }, |
| 16 => { |
| // First step. |
| let left = self.and(value, context.new_rvalue_from_int(typ, 0x5555)); |
| let left = self.shl(left, context.new_rvalue_from_int(typ, 1)); |
| let right = self.and(value, context.new_rvalue_from_int(typ, 0xAAAA)); |
| let right = self.lshr(right, context.new_rvalue_from_int(typ, 1)); |
| let step1 = self.or(left, right); |
| |
| // Second step. |
| let left = self.and(step1, context.new_rvalue_from_int(typ, 0x3333)); |
| let left = self.shl(left, context.new_rvalue_from_int(typ, 2)); |
| let right = self.and(step1, context.new_rvalue_from_int(typ, 0xCCCC)); |
| let right = self.lshr(right, context.new_rvalue_from_int(typ, 2)); |
| let step2 = self.or(left, right); |
| |
| // Third step. |
| let left = self.and(step2, context.new_rvalue_from_int(typ, 0x0F0F)); |
| let left = self.shl(left, context.new_rvalue_from_int(typ, 4)); |
| let right = self.and(step2, context.new_rvalue_from_int(typ, 0xF0F0)); |
| let right = self.lshr(right, context.new_rvalue_from_int(typ, 4)); |
| let step3 = self.or(left, right); |
| |
| // Fourth step. |
| let left = self.and(step3, context.new_rvalue_from_int(typ, 0x00FF)); |
| let left = self.shl(left, context.new_rvalue_from_int(typ, 8)); |
| let right = self.and(step3, context.new_rvalue_from_int(typ, 0xFF00)); |
| let right = self.lshr(right, context.new_rvalue_from_int(typ, 8)); |
| let step4 = self.or(left, right); |
| |
| step4 |
| }, |
| 32 => { |
| // TODO(antoyo): Refactor with other implementations. |
| // First step. |
| let left = self.and(value, context.new_rvalue_from_long(typ, 0x55555555)); |
| let left = self.shl(left, context.new_rvalue_from_long(typ, 1)); |
| let right = self.and(value, context.new_rvalue_from_long(typ, 0xAAAAAAAA)); |
| let right = self.lshr(right, context.new_rvalue_from_long(typ, 1)); |
| let step1 = self.or(left, right); |
| |
| // Second step. |
| let left = self.and(step1, context.new_rvalue_from_long(typ, 0x33333333)); |
| let left = self.shl(left, context.new_rvalue_from_long(typ, 2)); |
| let right = self.and(step1, context.new_rvalue_from_long(typ, 0xCCCCCCCC)); |
| let right = self.lshr(right, context.new_rvalue_from_long(typ, 2)); |
| let step2 = self.or(left, right); |
| |
| // Third step. |
| let left = self.and(step2, context.new_rvalue_from_long(typ, 0x0F0F0F0F)); |
| let left = self.shl(left, context.new_rvalue_from_long(typ, 4)); |
| let right = self.and(step2, context.new_rvalue_from_long(typ, 0xF0F0F0F0)); |
| let right = self.lshr(right, context.new_rvalue_from_long(typ, 4)); |
| let step3 = self.or(left, right); |
| |
| // Fourth step. |
| let left = self.and(step3, context.new_rvalue_from_long(typ, 0x00FF00FF)); |
| let left = self.shl(left, context.new_rvalue_from_long(typ, 8)); |
| let right = self.and(step3, context.new_rvalue_from_long(typ, 0xFF00FF00)); |
| let right = self.lshr(right, context.new_rvalue_from_long(typ, 8)); |
| let step4 = self.or(left, right); |
| |
| // Fifth step. |
| let left = self.and(step4, context.new_rvalue_from_long(typ, 0x0000FFFF)); |
| let left = self.shl(left, context.new_rvalue_from_long(typ, 16)); |
| let right = self.and(step4, context.new_rvalue_from_long(typ, 0xFFFF0000)); |
| let right = self.lshr(right, context.new_rvalue_from_long(typ, 16)); |
| let step5 = self.or(left, right); |
| |
| step5 |
| }, |
| 64 => { |
| // First step. |
| let left = self.shl(value, context.new_rvalue_from_long(typ, 32)); |
| let right = self.lshr(value, context.new_rvalue_from_long(typ, 32)); |
| let step1 = self.or(left, right); |
| |
| // Second step. |
| let left = self.and(step1, context.new_rvalue_from_long(typ, 0x0001FFFF0001FFFF)); |
| let left = self.shl(left, context.new_rvalue_from_long(typ, 15)); |
| let right = self.and(step1, context.new_rvalue_from_long(typ, 0xFFFE0000FFFE0000u64 as i64)); // TODO(antoyo): transmute the number instead? |
| let right = self.lshr(right, context.new_rvalue_from_long(typ, 17)); |
| let step2 = self.or(left, right); |
| |
| // Third step. |
| let left = self.lshr(step2, context.new_rvalue_from_long(typ, 10)); |
| let left = self.xor(step2, left); |
| let temp = self.and(left, context.new_rvalue_from_long(typ, 0x003F801F003F801F)); |
| |
| let left = self.shl(temp, context.new_rvalue_from_long(typ, 10)); |
| let left = self.or(temp, left); |
| let step3 = self.xor(left, step2); |
| |
| // Fourth step. |
| let left = self.lshr(step3, context.new_rvalue_from_long(typ, 4)); |
| let left = self.xor(step3, left); |
| let temp = self.and(left, context.new_rvalue_from_long(typ, 0x0E0384210E038421)); |
| |
| let left = self.shl(temp, context.new_rvalue_from_long(typ, 4)); |
| let left = self.or(temp, left); |
| let step4 = self.xor(left, step3); |
| |
| // Fifth step. |
| let left = self.lshr(step4, context.new_rvalue_from_long(typ, 2)); |
| let left = self.xor(step4, left); |
| let temp = self.and(left, context.new_rvalue_from_long(typ, 0x2248884222488842)); |
| |
| let left = self.shl(temp, context.new_rvalue_from_long(typ, 2)); |
| let left = self.or(temp, left); |
| let step5 = self.xor(left, step4); |
| |
| step5 |
| }, |
| 128 => { |
| // TODO(antoyo): find a more efficient implementation? |
| let sixty_four = self.gcc_int(typ, 64); |
| let right_shift = self.gcc_lshr(value, sixty_four); |
| let high = self.gcc_int_cast(right_shift, self.u64_type); |
| let low = self.gcc_int_cast(value, self.u64_type); |
| |
| let reversed_high = self.bit_reverse(64, high); |
| let reversed_low = self.bit_reverse(64, low); |
| |
| let new_low = self.gcc_int_cast(reversed_high, typ); |
| let new_high = self.shl(self.gcc_int_cast(reversed_low, typ), sixty_four); |
| |
| self.gcc_or(new_low, new_high) |
| }, |
| _ => { |
| panic!("cannot bit reverse with width = {}", width); |
| }, |
| }; |
| |
| self.gcc_int_cast(result, result_type) |
| } |
| |
| fn count_leading_zeroes(&mut self, width: u64, arg: RValue<'gcc>) -> RValue<'gcc> { |
| // TODO(antoyo): use width? |
| let arg_type = arg.get_type(); |
| let count_leading_zeroes = |
| // TODO(antoyo): write a new function Type::is_compatible_with(&Type) and use it here |
| // instead of using is_uint(). |
| if arg_type.is_uint(&self.cx) { |
| "__builtin_clz" |
| } |
| else if arg_type.is_ulong(&self.cx) { |
| "__builtin_clzl" |
| } |
| else if arg_type.is_ulonglong(&self.cx) { |
| "__builtin_clzll" |
| } |
| else if width == 128 { |
| // Algorithm from: https://stackoverflow.com/a/28433850/389119 |
| let array_type = self.context.new_array_type(None, arg_type, 3); |
| let result = self.current_func() |
| .new_local(None, array_type, "count_loading_zeroes_results"); |
| |
| let sixty_four = self.const_uint(arg_type, 64); |
| let shift = self.lshr(arg, sixty_four); |
| let high = self.gcc_int_cast(shift, self.u64_type); |
| let low = self.gcc_int_cast(arg, self.u64_type); |
| |
| let zero = self.context.new_rvalue_zero(self.usize_type); |
| let one = self.context.new_rvalue_one(self.usize_type); |
| let two = self.context.new_rvalue_from_long(self.usize_type, 2); |
| |
| let clzll = self.context.get_builtin_function("__builtin_clzll"); |
| |
| let first_elem = self.context.new_array_access(None, result, zero); |
| let first_value = self.gcc_int_cast(self.context.new_call(None, clzll, &[high]), arg_type); |
| self.llbb() |
| .add_assignment(None, first_elem, first_value); |
| |
| let second_elem = self.context.new_array_access(None, result, one); |
| let cast = self.gcc_int_cast(self.context.new_call(None, clzll, &[low]), arg_type); |
| let second_value = self.add(cast, sixty_four); |
| self.llbb() |
| .add_assignment(None, second_elem, second_value); |
| |
| let third_elem = self.context.new_array_access(None, result, two); |
| let third_value = self.const_uint(arg_type, 128); |
| self.llbb() |
| .add_assignment(None, third_elem, third_value); |
| |
| let not_high = self.context.new_unary_op(None, UnaryOp::LogicalNegate, self.u64_type, high); |
| let not_low = self.context.new_unary_op(None, UnaryOp::LogicalNegate, self.u64_type, low); |
| let not_low_and_not_high = not_low & not_high; |
| let index = not_high + not_low_and_not_high; |
| // NOTE: the following cast is necessary to avoid a GIMPLE verification failure in |
| // gcc. |
| // TODO(antoyo): do the correct verification in libgccjit to avoid an error at the |
| // compilation stage. |
| let index = self.context.new_cast(None, index, self.i32_type); |
| |
| let res = self.context.new_array_access(None, result, index); |
| |
| return self.gcc_int_cast(res.to_rvalue(), arg_type); |
| } |
| else { |
| let count_leading_zeroes = self.context.get_builtin_function("__builtin_clzll"); |
| let arg = self.context.new_cast(None, arg, self.ulonglong_type); |
| let diff = self.ulonglong_type.get_size() as i64 - arg_type.get_size() as i64; |
| let diff = self.context.new_rvalue_from_long(self.int_type, diff * 8); |
| let res = self.context.new_call(None, count_leading_zeroes, &[arg]) - diff; |
| return self.context.new_cast(None, res, arg_type); |
| }; |
| let count_leading_zeroes = self.context.get_builtin_function(count_leading_zeroes); |
| let res = self.context.new_call(None, count_leading_zeroes, &[arg]); |
| self.context.new_cast(None, res, arg_type) |
| } |
| |
| fn count_trailing_zeroes(&mut self, _width: u64, arg: RValue<'gcc>) -> RValue<'gcc> { |
| let result_type = arg.get_type(); |
| let arg = |
| if result_type.is_signed(self.cx) { |
| let new_type = result_type.to_unsigned(self.cx); |
| self.gcc_int_cast(arg, new_type) |
| } |
| else { |
| arg |
| }; |
| let arg_type = arg.get_type(); |
| let (count_trailing_zeroes, expected_type) = |
| // TODO(antoyo): write a new function Type::is_compatible_with(&Type) and use it here |
| // instead of using is_uint(). |
| if arg_type.is_uchar(&self.cx) || arg_type.is_ushort(&self.cx) || arg_type.is_uint(&self.cx) { |
| // NOTE: we don't need to & 0xFF for uchar because the result is undefined on zero. |
| ("__builtin_ctz", self.cx.uint_type) |
| } |
| else if arg_type.is_ulong(&self.cx) { |
| ("__builtin_ctzl", self.cx.ulong_type) |
| } |
| else if arg_type.is_ulonglong(&self.cx) { |
| ("__builtin_ctzll", self.cx.ulonglong_type) |
| } |
| else if arg_type.is_u128(&self.cx) { |
| // Adapted from the algorithm to count leading zeroes from: https://stackoverflow.com/a/28433850/389119 |
| let array_type = self.context.new_array_type(None, arg_type, 3); |
| let result = self.current_func() |
| .new_local(None, array_type, "count_loading_zeroes_results"); |
| |
| let sixty_four = self.gcc_int(arg_type, 64); |
| let shift = self.gcc_lshr(arg, sixty_four); |
| let high = self.gcc_int_cast(shift, self.u64_type); |
| let low = self.gcc_int_cast(arg, self.u64_type); |
| |
| let zero = self.context.new_rvalue_zero(self.usize_type); |
| let one = self.context.new_rvalue_one(self.usize_type); |
| let two = self.context.new_rvalue_from_long(self.usize_type, 2); |
| |
| let ctzll = self.context.get_builtin_function("__builtin_ctzll"); |
| |
| let first_elem = self.context.new_array_access(None, result, zero); |
| let first_value = self.gcc_int_cast(self.context.new_call(None, ctzll, &[low]), arg_type); |
| self.llbb() |
| .add_assignment(None, first_elem, first_value); |
| |
| let second_elem = self.context.new_array_access(None, result, one); |
| let second_value = self.gcc_add(self.gcc_int_cast(self.context.new_call(None, ctzll, &[high]), arg_type), sixty_four); |
| self.llbb() |
| .add_assignment(None, second_elem, second_value); |
| |
| let third_elem = self.context.new_array_access(None, result, two); |
| let third_value = self.gcc_int(arg_type, 128); |
| self.llbb() |
| .add_assignment(None, third_elem, third_value); |
| |
| let not_low = self.context.new_unary_op(None, UnaryOp::LogicalNegate, self.u64_type, low); |
| let not_high = self.context.new_unary_op(None, UnaryOp::LogicalNegate, self.u64_type, high); |
| let not_low_and_not_high = not_low & not_high; |
| let index = not_low + not_low_and_not_high; |
| // NOTE: the following cast is necessary to avoid a GIMPLE verification failure in |
| // gcc. |
| // TODO(antoyo): do the correct verification in libgccjit to avoid an error at the |
| // compilation stage. |
| let index = self.context.new_cast(None, index, self.i32_type); |
| |
| let res = self.context.new_array_access(None, result, index); |
| |
| return self.gcc_int_cast(res.to_rvalue(), result_type); |
| } |
| else { |
| let count_trailing_zeroes = self.context.get_builtin_function("__builtin_ctzll"); |
| let arg_size = arg_type.get_size(); |
| let casted_arg = self.context.new_cast(None, arg, self.ulonglong_type); |
| let byte_diff = self.ulonglong_type.get_size() as i64 - arg_size as i64; |
| let diff = self.context.new_rvalue_from_long(self.int_type, byte_diff * 8); |
| let mask = self.context.new_rvalue_from_long(arg_type, -1); // To get the value with all bits set. |
| let masked = mask & self.context.new_unary_op(None, UnaryOp::BitwiseNegate, arg_type, arg); |
| let cond = self.context.new_comparison(None, ComparisonOp::Equals, masked, mask); |
| let diff = diff * self.context.new_cast(None, cond, self.int_type); |
| let res = self.context.new_call(None, count_trailing_zeroes, &[casted_arg]) - diff; |
| return self.context.new_cast(None, res, result_type); |
| }; |
| let count_trailing_zeroes = self.context.get_builtin_function(count_trailing_zeroes); |
| let arg = |
| if arg_type != expected_type { |
| self.context.new_cast(None, arg, expected_type) |
| } |
| else { |
| arg |
| }; |
| let res = self.context.new_call(None, count_trailing_zeroes, &[arg]); |
| self.context.new_cast(None, res, result_type) |
| } |
| |
| fn pop_count(&mut self, value: RValue<'gcc>) -> RValue<'gcc> { |
| // TODO(antoyo): use the optimized version with fewer operations. |
| let result_type = value.get_type(); |
| let value_type = result_type.to_unsigned(self.cx); |
| |
| let value = |
| if result_type.is_signed(self.cx) { |
| self.gcc_int_cast(value, value_type) |
| } |
| else { |
| value |
| }; |
| |
| if value_type.is_u128(&self.cx) { |
| // TODO(antoyo): implement in the normal algorithm below to have a more efficient |
| // implementation (that does not require a call to __popcountdi2). |
| let popcount = self.context.get_builtin_function("__builtin_popcountll"); |
| let sixty_four = self.gcc_int(value_type, 64); |
| let right_shift = self.gcc_lshr(value, sixty_four); |
| let high = self.gcc_int_cast(right_shift, self.cx.ulonglong_type); |
| let high = self.context.new_call(None, popcount, &[high]); |
| let low = self.gcc_int_cast(value, self.cx.ulonglong_type); |
| let low = self.context.new_call(None, popcount, &[low]); |
| let res = high + low; |
| return self.gcc_int_cast(res, result_type); |
| } |
| |
| // First step. |
| let mask = self.context.new_rvalue_from_long(value_type, 0x5555555555555555); |
| let left = value & mask; |
| let shifted = value >> self.context.new_rvalue_from_int(value_type, 1); |
| let right = shifted & mask; |
| let value = left + right; |
| |
| // Second step. |
| let mask = self.context.new_rvalue_from_long(value_type, 0x3333333333333333); |
| let left = value & mask; |
| let shifted = value >> self.context.new_rvalue_from_int(value_type, 2); |
| let right = shifted & mask; |
| let value = left + right; |
| |
| // Third step. |
| let mask = self.context.new_rvalue_from_long(value_type, 0x0F0F0F0F0F0F0F0F); |
| let left = value & mask; |
| let shifted = value >> self.context.new_rvalue_from_int(value_type, 4); |
| let right = shifted & mask; |
| let value = left + right; |
| |
| if value_type.is_u8(&self.cx) { |
| return self.context.new_cast(None, value, result_type); |
| } |
| |
| // Fourth step. |
| let mask = self.context.new_rvalue_from_long(value_type, 0x00FF00FF00FF00FF); |
| let left = value & mask; |
| let shifted = value >> self.context.new_rvalue_from_int(value_type, 8); |
| let right = shifted & mask; |
| let value = left + right; |
| |
| if value_type.is_u16(&self.cx) { |
| return self.context.new_cast(None, value, result_type); |
| } |
| |
| // Fifth step. |
| let mask = self.context.new_rvalue_from_long(value_type, 0x0000FFFF0000FFFF); |
| let left = value & mask; |
| let shifted = value >> self.context.new_rvalue_from_int(value_type, 16); |
| let right = shifted & mask; |
| let value = left + right; |
| |
| if value_type.is_u32(&self.cx) { |
| return self.context.new_cast(None, value, result_type); |
| } |
| |
| // Sixth step. |
| let mask = self.context.new_rvalue_from_long(value_type, 0x00000000FFFFFFFF); |
| let left = value & mask; |
| let shifted = value >> self.context.new_rvalue_from_int(value_type, 32); |
| let right = shifted & mask; |
| let value = left + right; |
| |
| self.context.new_cast(None, value, result_type) |
| } |
| |
| // Algorithm from: https://blog.regehr.org/archives/1063 |
| fn rotate_left(&mut self, value: RValue<'gcc>, shift: RValue<'gcc>, width: u64) -> RValue<'gcc> { |
| let max = self.const_uint(shift.get_type(), width); |
| let shift = self.urem(shift, max); |
| let lhs = self.shl(value, shift); |
| let result_neg = self.neg(shift); |
| let result_and = |
| self.and( |
| result_neg, |
| self.const_uint(shift.get_type(), width - 1), |
| ); |
| let rhs = self.lshr(value, result_and); |
| self.or(lhs, rhs) |
| } |
| |
| // Algorithm from: https://blog.regehr.org/archives/1063 |
| fn rotate_right(&mut self, value: RValue<'gcc>, shift: RValue<'gcc>, width: u64) -> RValue<'gcc> { |
| let max = self.const_uint(shift.get_type(), width); |
| let shift = self.urem(shift, max); |
| let lhs = self.lshr(value, shift); |
| let result_neg = self.neg(shift); |
| let result_and = |
| self.and( |
| result_neg, |
| self.const_uint(shift.get_type(), width - 1), |
| ); |
| let rhs = self.shl(value, result_and); |
| self.or(lhs, rhs) |
| } |
| |
| fn saturating_add(&mut self, lhs: RValue<'gcc>, rhs: RValue<'gcc>, signed: bool, width: u64) -> RValue<'gcc> { |
| let result_type = lhs.get_type(); |
| if signed { |
| // Based on algorithm from: https://stackoverflow.com/a/56531252/389119 |
| let func = self.current_func.borrow().expect("func"); |
| let res = func.new_local(None, result_type, "saturating_sum"); |
| let supports_native_type = self.is_native_int_type(result_type); |
| let overflow = |
| if supports_native_type { |
| let func_name = |
| match width { |
| 8 => "__builtin_add_overflow", |
| 16 => "__builtin_add_overflow", |
| 32 => "__builtin_sadd_overflow", |
| 64 => "__builtin_saddll_overflow", |
| 128 => "__builtin_add_overflow", |
| _ => unreachable!(), |
| }; |
| let overflow_func = self.context.get_builtin_function(func_name); |
| self.overflow_call(overflow_func, &[lhs, rhs, res.get_address(None)], None) |
| } |
| else { |
| let func_name = |
| match width { |
| 128 => "__rust_i128_addo", |
| _ => unreachable!(), |
| }; |
| let param_a = self.context.new_parameter(None, result_type, "a"); |
| let param_b = self.context.new_parameter(None, result_type, "b"); |
| let result_field = self.context.new_field(None, result_type, "result"); |
| let overflow_field = self.context.new_field(None, self.bool_type, "overflow"); |
| let return_type = self.context.new_struct_type(None, "result_overflow", &[result_field, overflow_field]); |
| let func = self.context.new_function(None, FunctionType::Extern, return_type.as_type(), &[param_a, param_b], func_name, false); |
| let result = self.context.new_call(None, func, &[lhs, rhs]); |
| let overflow = result.access_field(None, overflow_field); |
| let int_result = result.access_field(None, result_field); |
| self.llbb().add_assignment(None, res, int_result); |
| overflow |
| }; |
| |
| let then_block = func.new_block("then"); |
| let after_block = func.new_block("after"); |
| |
| // Return `result_type`'s maximum or minimum value on overflow |
| // NOTE: convert the type to unsigned to have an unsigned shift. |
| let unsigned_type = result_type.to_unsigned(&self.cx); |
| let shifted = self.gcc_lshr(self.gcc_int_cast(lhs, unsigned_type), self.gcc_int(unsigned_type, width as i64 - 1)); |
| let uint_max = self.gcc_not(self.gcc_int(unsigned_type, 0)); |
| let int_max = self.gcc_lshr(uint_max, self.gcc_int(unsigned_type, 1)); |
| then_block.add_assignment(None, res, self.gcc_int_cast(self.gcc_add(shifted, int_max), result_type)); |
| then_block.end_with_jump(None, after_block); |
| |
| self.llbb().end_with_conditional(None, overflow, then_block, after_block); |
| |
| // NOTE: since jumps were added in a place rustc does not |
| // expect, the current block in the state need to be updated. |
| self.switch_to_block(after_block); |
| |
| res.to_rvalue() |
| } |
| else { |
| // Algorithm from: http://locklessinc.com/articles/sat_arithmetic/ |
| let res = self.gcc_add(lhs, rhs); |
| let cond = self.gcc_icmp(IntPredicate::IntULT, res, lhs); |
| let value = self.gcc_neg(self.gcc_int_cast(cond, result_type)); |
| self.gcc_or(res, value) |
| } |
| } |
| |
| // Algorithm from: https://locklessinc.com/articles/sat_arithmetic/ |
| fn saturating_sub(&mut self, lhs: RValue<'gcc>, rhs: RValue<'gcc>, signed: bool, width: u64) -> RValue<'gcc> { |
| let result_type = lhs.get_type(); |
| if signed { |
| // Based on algorithm from: https://stackoverflow.com/a/56531252/389119 |
| let func = self.current_func.borrow().expect("func"); |
| let res = func.new_local(None, result_type, "saturating_diff"); |
| let supports_native_type = self.is_native_int_type(result_type); |
| let overflow = |
| if supports_native_type { |
| let func_name = |
| match width { |
| 8 => "__builtin_sub_overflow", |
| 16 => "__builtin_sub_overflow", |
| 32 => "__builtin_ssub_overflow", |
| 64 => "__builtin_ssubll_overflow", |
| 128 => "__builtin_sub_overflow", |
| _ => unreachable!(), |
| }; |
| let overflow_func = self.context.get_builtin_function(func_name); |
| self.overflow_call(overflow_func, &[lhs, rhs, res.get_address(None)], None) |
| } |
| else { |
| let func_name = |
| match width { |
| 128 => "__rust_i128_subo", |
| _ => unreachable!(), |
| }; |
| let param_a = self.context.new_parameter(None, result_type, "a"); |
| let param_b = self.context.new_parameter(None, result_type, "b"); |
| let result_field = self.context.new_field(None, result_type, "result"); |
| let overflow_field = self.context.new_field(None, self.bool_type, "overflow"); |
| let return_type = self.context.new_struct_type(None, "result_overflow", &[result_field, overflow_field]); |
| let func = self.context.new_function(None, FunctionType::Extern, return_type.as_type(), &[param_a, param_b], func_name, false); |
| let result = self.context.new_call(None, func, &[lhs, rhs]); |
| let overflow = result.access_field(None, overflow_field); |
| let int_result = result.access_field(None, result_field); |
| self.llbb().add_assignment(None, res, int_result); |
| overflow |
| }; |
| |
| let then_block = func.new_block("then"); |
| let after_block = func.new_block("after"); |
| |
| // Return `result_type`'s maximum or minimum value on overflow |
| // NOTE: convert the type to unsigned to have an unsigned shift. |
| let unsigned_type = result_type.to_unsigned(&self.cx); |
| let shifted = self.gcc_lshr(self.gcc_int_cast(lhs, unsigned_type), self.gcc_int(unsigned_type, width as i64 - 1)); |
| let uint_max = self.gcc_not(self.gcc_int(unsigned_type, 0)); |
| let int_max = self.gcc_lshr(uint_max, self.gcc_int(unsigned_type, 1)); |
| then_block.add_assignment(None, res, self.gcc_int_cast(self.gcc_add(shifted, int_max), result_type)); |
| then_block.end_with_jump(None, after_block); |
| |
| self.llbb().end_with_conditional(None, overflow, then_block, after_block); |
| |
| // NOTE: since jumps were added in a place rustc does not |
| // expect, the current block in the state need to be updated. |
| self.switch_to_block(after_block); |
| |
| res.to_rvalue() |
| } |
| else { |
| let res = self.gcc_sub(lhs, rhs); |
| let comparison = self.gcc_icmp(IntPredicate::IntULE, res, lhs); |
| let value = self.gcc_neg(self.gcc_int_cast(comparison, result_type)); |
| self.gcc_and(res, value) |
| } |
| } |
| } |
| |
| fn try_intrinsic<'gcc, 'tcx>(bx: &mut Builder<'_, 'gcc, 'tcx>, try_func: RValue<'gcc>, data: RValue<'gcc>, _catch_func: RValue<'gcc>, dest: RValue<'gcc>) { |
| // NOTE: the `|| true` here is to use the panic=abort strategy with panic=unwind too |
| if bx.sess().panic_strategy() == PanicStrategy::Abort || true { |
| // TODO(bjorn3): Properly implement unwinding and remove the `|| true` once this is done. |
| bx.call(bx.type_void(), 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()) { |
| unimplemented!(); |
| } |
| else { |
| unimplemented!(); |
| } |
| } |
