Remove unchecked_add/sub/mul/shl/shr from CTFE/cg_ssa/cg_clif

Author: scottmcm

compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs

@@ -472,25 +472,11 @@ fn codegen_regular_intrinsic_call<'tcx>(
             ret.write_cvalue(fx, CValue::by_val(align, usize_layout));
         }
 
-        sym::unchecked_add
-        | sym::unchecked_sub
-        | sym::unchecked_mul
-        | sym::exact_div
-        | sym::unchecked_shl
-        | sym::unchecked_shr => {
+        sym::exact_div => {
             intrinsic_args!(fx, args => (x, y); intrinsic);
 
-            // FIXME trap on overflow
-            let bin_op = match intrinsic {
-                sym::unchecked_add => BinOp::Add,
-                sym::unchecked_sub => BinOp::Sub,
-                sym::unchecked_mul => BinOp::Mul,
-                sym::exact_div => BinOp::Div,
-                sym::unchecked_shl => BinOp::Shl,
-                sym::unchecked_shr => BinOp::Shr,
-                _ => unreachable!(),
-            };
-            let res = crate::num::codegen_int_binop(fx, bin_op, x, y);
+            // FIXME trap on inexact
+            let res = crate::num::codegen_int_binop(fx, BinOp::Div, x, y);
             ret.write_cvalue(fx, res);
         }
         sym::saturating_add | sym::saturating_sub => {

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -211,52 +211,15 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 args[1].val.unaligned_volatile_store(bx, dst);
                 return;
             }
-            | sym::unchecked_shl
-            | sym::unchecked_shr
-            | sym::unchecked_add
-            | sym::unchecked_sub
-            | sym::unchecked_mul
-            | sym::exact_div => {
+            sym::exact_div => {
                 let ty = arg_tys[0];
                 match int_type_width_signed(ty, bx.tcx()) {
-                    Some((_width, signed)) => match name {
-                        sym::exact_div => {
-                            if signed {
-                                bx.exactsdiv(args[0].immediate(), args[1].immediate())
-                            } else {
-                                bx.exactudiv(args[0].immediate(), args[1].immediate())
-                            }
-                        }
-                        sym::unchecked_shl => bx.shl(args[0].immediate(), args[1].immediate()),
-                        sym::unchecked_shr => {
-                            if signed {
-                                bx.ashr(args[0].immediate(), args[1].immediate())
-                            } else {
-                                bx.lshr(args[0].immediate(), args[1].immediate())
-                            }
-                        }
-                        sym::unchecked_add => {
-                            if signed {
-                                bx.unchecked_sadd(args[0].immediate(), args[1].immediate())
-                            } else {
-                                bx.unchecked_uadd(args[0].immediate(), args[1].immediate())
-                            }
-                        }
-                        sym::unchecked_sub => {
-                            if signed {
-                                bx.unchecked_ssub(args[0].immediate(), args[1].immediate())
-                            } else {
-                                bx.unchecked_usub(args[0].immediate(), args[1].immediate())
-                            }
-                        }
-                        sym::unchecked_mul => {
-                            if signed {
-                                bx.unchecked_smul(args[0].immediate(), args[1].immediate())
-                            } else {
-                                bx.unchecked_umul(args[0].immediate(), args[1].immediate())
-                            }
+                    Some((_width, signed)) => {
+                        if signed {
+                            bx.exactsdiv(args[0].immediate(), args[1].immediate())
+                        } else {
+                            bx.exactudiv(args[0].immediate(), args[1].immediate())
                         }
-                        _ => bug!(),
                     },
                     None => {
                         bx.tcx().sess.emit_err(InvalidMonomorphization::BasicIntegerType { span, name, ty });

compiler/rustc_const_eval/src/interpret/intrinsics.rs

@@ -234,37 +234,6 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 let r = self.read_immediate(&args[1])?;
                 self.exact_div(&l, &r, dest)?;
             }
-            sym::unchecked_shl
-            | sym::unchecked_shr
-            | sym::unchecked_add
-            | sym::unchecked_sub
-            | sym::unchecked_mul => {
-                let l = self.read_immediate(&args[0])?;
-                let r = self.read_immediate(&args[1])?;
-                let bin_op = match intrinsic_name {
-                    sym::unchecked_shl => BinOp::Shl,
-                    sym::unchecked_shr => BinOp::Shr,
-                    sym::unchecked_add => BinOp::Add,
-                    sym::unchecked_sub => BinOp::Sub,
-                    sym::unchecked_mul => BinOp::Mul,
-                    _ => bug!(),
-                };
-                let (val, overflowed, _ty) = self.overflowing_binary_op(bin_op, &l, &r)?;
-                if overflowed {
-                    let layout = self.layout_of(substs.type_at(0))?;
-                    let r_val = r.to_scalar().to_bits(layout.size)?;
-                    if let sym::unchecked_shl | sym::unchecked_shr = intrinsic_name {
-                        throw_ub_custom!(
-                            fluent::const_eval_overflow_shift,
-                            val = r_val,
-                            name = intrinsic_name
-                        );
-                    } else {
-                        throw_ub_custom!(fluent::const_eval_overflow, name = intrinsic_name);
-                    }
-                }
-                self.write_scalar(val, dest)?;
-            }
             sym::rotate_left | sym::rotate_right => {
                 // rotate_left: (X << (S % BW)) | (X >> ((BW - S) % BW))
                 // rotate_right: (X << ((BW - S) % BW)) | (X >> (S % BW))