| //! Replaces 128-bit operators with lang item calls where necessary |
| |
| use crate::prelude::*; |
| |
| pub(crate) fn maybe_codegen<'tcx>( |
| fx: &mut FunctionCx<'_, 'tcx, impl Module>, |
| bin_op: BinOp, |
| checked: bool, |
| lhs: CValue<'tcx>, |
| rhs: CValue<'tcx>, |
| ) -> Option<CValue<'tcx>> { |
| if lhs.layout().ty != fx.tcx.types.u128 && lhs.layout().ty != fx.tcx.types.i128 { |
| return None; |
| } |
| |
| let lhs_val = lhs.load_scalar(fx); |
| let rhs_val = rhs.load_scalar(fx); |
| |
| let is_signed = type_sign(lhs.layout().ty); |
| |
| match bin_op { |
| BinOp::BitAnd | BinOp::BitOr | BinOp::BitXor => { |
| assert!(!checked); |
| None |
| } |
| BinOp::Add | BinOp::Sub if !checked => None, |
| BinOp::Add => { |
| let out_ty = fx.tcx.mk_tup([lhs.layout().ty, fx.tcx.types.bool].iter()); |
| return Some(if is_signed { |
| fx.easy_call("__rust_i128_addo", &[lhs, rhs], out_ty) |
| } else { |
| fx.easy_call("__rust_u128_addo", &[lhs, rhs], out_ty) |
| }); |
| } |
| BinOp::Sub => { |
| let out_ty = fx.tcx.mk_tup([lhs.layout().ty, fx.tcx.types.bool].iter()); |
| return Some(if is_signed { |
| fx.easy_call("__rust_i128_subo", &[lhs, rhs], out_ty) |
| } else { |
| fx.easy_call("__rust_u128_subo", &[lhs, rhs], out_ty) |
| }); |
| } |
| BinOp::Offset => unreachable!("offset should only be used on pointers, not 128bit ints"), |
| BinOp::Mul => { |
| let res = if checked { |
| let out_ty = fx.tcx.mk_tup([lhs.layout().ty, fx.tcx.types.bool].iter()); |
| if is_signed { |
| fx.easy_call("__rust_i128_mulo", &[lhs, rhs], out_ty) |
| } else { |
| fx.easy_call("__rust_u128_mulo", &[lhs, rhs], out_ty) |
| } |
| } else { |
| let val_ty = if is_signed { |
| fx.tcx.types.i128 |
| } else { |
| fx.tcx.types.u128 |
| }; |
| fx.easy_call("__multi3", &[lhs, rhs], val_ty) |
| }; |
| Some(res) |
| } |
| BinOp::Div => { |
| assert!(!checked); |
| if is_signed { |
| Some(fx.easy_call("__divti3", &[lhs, rhs], fx.tcx.types.i128)) |
| } else { |
| Some(fx.easy_call("__udivti3", &[lhs, rhs], fx.tcx.types.u128)) |
| } |
| } |
| BinOp::Rem => { |
| assert!(!checked); |
| if is_signed { |
| Some(fx.easy_call("__modti3", &[lhs, rhs], fx.tcx.types.i128)) |
| } else { |
| Some(fx.easy_call("__umodti3", &[lhs, rhs], fx.tcx.types.u128)) |
| } |
| } |
| BinOp::Lt | BinOp::Le | BinOp::Eq | BinOp::Ge | BinOp::Gt | BinOp::Ne => { |
| assert!(!checked); |
| None |
| } |
| BinOp::Shl | BinOp::Shr => { |
| let is_overflow = if checked { |
| // rhs >= 128 |
| |
| // FIXME support non 128bit rhs |
| /*let (rhs_lsb, rhs_msb) = fx.bcx.ins().isplit(rhs_val); |
| let rhs_msb_gt_0 = fx.bcx.ins().icmp_imm(IntCC::NotEqual, rhs_msb, 0); |
| let rhs_lsb_ge_128 = fx.bcx.ins().icmp_imm(IntCC::SignedGreaterThan, rhs_lsb, 127); |
| let is_overflow = fx.bcx.ins().bor(rhs_msb_gt_0, rhs_lsb_ge_128);*/ |
| let is_overflow = fx.bcx.ins().bconst(types::B1, false); |
| |
| Some(fx.bcx.ins().bint(types::I8, is_overflow)) |
| } else { |
| None |
| }; |
| |
| // Optimize `val >> 64`, because compiler_builtins uses it to deconstruct an 128bit |
| // integer into its lsb and msb. |
| // https://github.com/rust-lang-nursery/compiler-builtins/blob/79a6a1603d5672cbb9187ff41ff4d9b5048ac1cb/src/int/mod.rs#L217 |
| if resolve_value_imm(fx.bcx.func, rhs_val) == Some(64) { |
| let (lhs_lsb, lhs_msb) = fx.bcx.ins().isplit(lhs_val); |
| let all_zeros = fx.bcx.ins().iconst(types::I64, 0); |
| let val = match (bin_op, is_signed) { |
| (BinOp::Shr, false) => { |
| let val = fx.bcx.ins().iconcat(lhs_msb, all_zeros); |
| Some(CValue::by_val(val, fx.layout_of(fx.tcx.types.u128))) |
| } |
| (BinOp::Shr, true) => { |
| let sign = fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, lhs_msb, 0); |
| let all_ones = fx.bcx.ins().iconst(types::I64, u64::MAX as i64); |
| let all_sign_bits = fx.bcx.ins().select(sign, all_zeros, all_ones); |
| |
| let val = fx.bcx.ins().iconcat(lhs_msb, all_sign_bits); |
| Some(CValue::by_val(val, fx.layout_of(fx.tcx.types.i128))) |
| } |
| (BinOp::Shl, _) => { |
| let val_ty = if is_signed { |
| fx.tcx.types.i128 |
| } else { |
| fx.tcx.types.u128 |
| }; |
| let val = fx.bcx.ins().iconcat(all_zeros, lhs_lsb); |
| Some(CValue::by_val(val, fx.layout_of(val_ty))) |
| } |
| _ => None, |
| }; |
| if let Some(val) = val { |
| if let Some(is_overflow) = is_overflow { |
| let out_ty = fx.tcx.mk_tup([lhs.layout().ty, fx.tcx.types.bool].iter()); |
| let val = val.load_scalar(fx); |
| return Some(CValue::by_val_pair(val, is_overflow, fx.layout_of(out_ty))); |
| } else { |
| return Some(val); |
| } |
| } |
| } |
| |
| let truncated_rhs = clif_intcast(fx, rhs_val, types::I32, false); |
| let truncated_rhs = CValue::by_val(truncated_rhs, fx.layout_of(fx.tcx.types.u32)); |
| let val = match (bin_op, is_signed) { |
| (BinOp::Shl, false) => { |
| fx.easy_call("__ashlti3", &[lhs, truncated_rhs], fx.tcx.types.u128) |
| } |
| (BinOp::Shl, true) => { |
| fx.easy_call("__ashlti3", &[lhs, truncated_rhs], fx.tcx.types.i128) |
| } |
| (BinOp::Shr, false) => { |
| fx.easy_call("__lshrti3", &[lhs, truncated_rhs], fx.tcx.types.u128) |
| } |
| (BinOp::Shr, true) => { |
| fx.easy_call("__ashrti3", &[lhs, truncated_rhs], fx.tcx.types.i128) |
| } |
| (_, _) => unreachable!(), |
| }; |
| if let Some(is_overflow) = is_overflow { |
| let out_ty = fx.tcx.mk_tup([lhs.layout().ty, fx.tcx.types.bool].iter()); |
| let val = val.load_scalar(fx); |
| Some(CValue::by_val_pair(val, is_overflow, fx.layout_of(out_ty))) |
| } else { |
| Some(val) |
| } |
| } |
| } |
| } |
