Experiment: remove hack

Author: Nadrieril

compiler/rustc_mir_build/src/build/matches/test.rs

@@ -216,6 +216,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
             target_blocks
         };
+        let target_blocks = make_target_blocks(self);
 
         let place = place_builder.to_place(self);
         let place_ty = place.ty(&self.local_decls, self.tcx);
@@ -224,7 +225,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         let source_info = self.source_info(test.span);
         match test.kind {
             TestKind::Switch { adt_def, ref variants } => {
-                let target_blocks = make_target_blocks(self);
                 // Variants is a BitVec of indexes into adt_def.variants.
                 let num_enum_variants = adt_def.variants().len();
                 debug_assert_eq!(target_blocks.len(), num_enum_variants + 1);
@@ -270,7 +270,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             }
 
             TestKind::SwitchInt { switch_ty, ref options } => {
-                let target_blocks = make_target_blocks(self);
                 let terminator = if *switch_ty.kind() == ty::Bool {
                     assert!(!options.is_empty() && options.len() <= 2);
                     let [first_bb, second_bb] = *target_blocks else {
@@ -340,7 +339,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     );
                     self.non_scalar_compare(
                         eq_block,
-                        make_target_blocks,
+                        target_blocks,
                         source_info,
                         value,
                         ref_str,
@@ -351,15 +350,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 if !ty.is_scalar() {
                     // Use `PartialEq::eq` instead of `BinOp::Eq`
                     // (the binop can only handle primitives)
-                    self.non_scalar_compare(
-                        block,
-                        make_target_blocks,
-                        source_info,
-                        value,
-                        place,
-                        ty,
-                    );
-                } else if let [success, fail] = *make_target_blocks(self) {
+                    self.non_scalar_compare(block, target_blocks, source_info, value, place, ty);
+                } else if let [success, fail] = *target_blocks {
                     assert_eq!(value.ty(), ty);
                     let expect = self.literal_operand(test.span, value);
                     let val = Operand::Copy(place);
@@ -371,7 +363,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
             TestKind::Range(ref range) => {
                 let lower_bound_success = self.cfg.start_new_block();
-                let target_blocks = make_target_blocks(self);
 
                 // Test `val` by computing `lo <= val && val <= hi`, using primitive comparisons.
                 // FIXME: skip useless comparison when the range is half-open.
@@ -401,8 +392,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             }
 
             TestKind::Len { len, op } => {
-                let target_blocks = make_target_blocks(self);
-
                 let usize_ty = self.tcx.types.usize;
                 let actual = self.temp(usize_ty, test.span);
 
@@ -466,7 +455,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
     fn non_scalar_compare(
         &mut self,
         block: BasicBlock,
-        make_target_blocks: impl FnOnce(&mut Self) -> Vec<BasicBlock>,
+        target_blocks: Vec<BasicBlock>,
         source_info: SourceInfo,
         value: Const<'tcx>,
         mut val: Place<'tcx>,
@@ -591,7 +580,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         );
         self.diverge_from(block);
 
-        let [success_block, fail_block] = *make_target_blocks(self) else {
+        let [success_block, fail_block] = *target_blocks else {
             bug!("`TestKind::Eq` should have two target blocks")
         };
         // check the result

tests/mir-opt/exponential_or.match_tuple.SimplifyCfg-initial.after.mir

@@ -38,22 +38,22 @@ fn match_tuple(_1: (u32, bool, Option<i32>, u32)) -> u32 {
 
     bb4: {
         _5 = Le(const 6_u32, (_1.3: u32));
-        switchInt(move _5) -> [0: bb6, otherwise: bb5];
+        switchInt(move _5) -> [0: bb5, otherwise: bb7];
     }
 
     bb5: {
-        _6 = Le((_1.3: u32), const 9_u32);
-        switchInt(move _6) -> [0: bb6, otherwise: bb8];
+        _3 = Le(const 13_u32, (_1.3: u32));
+        switchInt(move _3) -> [0: bb1, otherwise: bb6];
     }
 
     bb6: {
-        _3 = Le(const 13_u32, (_1.3: u32));
-        switchInt(move _3) -> [0: bb1, otherwise: bb7];
+        _4 = Le((_1.3: u32), const 16_u32);
+        switchInt(move _4) -> [0: bb1, otherwise: bb8];
     }
 
     bb7: {
-        _4 = Le((_1.3: u32), const 16_u32);
-        switchInt(move _4) -> [0: bb1, otherwise: bb8];
+        _6 = Le((_1.3: u32), const 9_u32);
+        switchInt(move _6) -> [0: bb5, otherwise: bb8];
     }
 
     bb8: {

tests/mir-opt/match_test.main.SimplifyCfg-initial.after.mir

@@ -28,43 +28,43 @@ fn main() -> () {
         StorageLive(_3);
         PlaceMention(_1);
         _6 = Le(const 0_i32, _1);
-        switchInt(move _6) -> [0: bb4, otherwise: bb1];
+        switchInt(move _6) -> [0: bb3, otherwise: bb8];
     }
 
     bb1: {
-        _7 = Lt(_1, const 10_i32);
-        switchInt(move _7) -> [0: bb4, otherwise: bb2];
+        falseEdge -> [real: bb9, imaginary: bb4];
     }
 
     bb2: {
-        falseEdge -> [real: bb9, imaginary: bb6];
+        _3 = const 3_i32;
+        goto -> bb14;
     }
 
     bb3: {
-        _3 = const 3_i32;
-        goto -> bb14;
+        _4 = Le(const 10_i32, _1);
+        switchInt(move _4) -> [0: bb5, otherwise: bb7];
     }
 
     bb4: {
-        _4 = Le(const 10_i32, _1);
-        switchInt(move _4) -> [0: bb7, otherwise: bb5];
+        falseEdge -> [real: bb12, imaginary: bb6];
     }
 
     bb5: {
-        _5 = Le(_1, const 20_i32);
-        switchInt(move _5) -> [0: bb7, otherwise: bb6];
+        switchInt(_1) -> [4294967295: bb6, otherwise: bb2];
     }
 
     bb6: {
-        falseEdge -> [real: bb12, imaginary: bb8];
+        falseEdge -> [real: bb13, imaginary: bb2];
     }
 
     bb7: {
-        switchInt(_1) -> [4294967295: bb8, otherwise: bb3];
+        _5 = Le(_1, const 20_i32);
+        switchInt(move _5) -> [0: bb5, otherwise: bb4];
     }
 
     bb8: {
-        falseEdge -> [real: bb13, imaginary: bb3];
+        _7 = Lt(_1, const 10_i32);
+        switchInt(move _7) -> [0: bb3, otherwise: bb1];
     }
 
     bb9: {
@@ -83,7 +83,7 @@ fn main() -> () {
 
     bb11: {
         StorageDead(_9);
-        falseEdge -> [real: bb3, imaginary: bb6];
+        falseEdge -> [real: bb2, imaginary: bb4];
     }
 
     bb12: {