kill temp early

Author: ouz-a

compiler/rustc_mir_transform/src/deref_separator.rs

@@ -8,7 +8,6 @@ pub fn deref_finder<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
     let mut patch = MirPatch::new(body);
     let (basic_blocks, local_decl) = body.basic_blocks_and_local_decls_mut();
     for (block, data) in basic_blocks.iter_enumerated_mut() {
-        let statement_len = data.statements.len();
         for (i, stmt) in data.statements.iter_mut().enumerate() {
             match stmt.kind {
                 StatementKind::Assign(box (og_place, Rvalue::Ref(region, borrow_knd, place))) => {
@@ -49,7 +48,7 @@ pub fn deref_finder<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
                             *stmt = new_stmt;
 
                             // Since our job with the temp is done it should be gone
-                            let loc = Location { block: block, statement_index: statement_len };
+                            let loc = Location { block: block, statement_index: i + 1 };
                             patch.add_statement(loc, StatementKind::StorageDead(temp));
 
                             // As all projections are off the base projection, if there are

src/test/mir-opt/derefer_test.main.Derefer.diff

@@ -38,18 +38,18 @@
 +         StorageLive(_6);                 // scope 2 at $DIR/derefer_test.rs:5:13: 5:26
 +         _6 = move (_2.1: &mut (i32, i32)); // scope 2 at $DIR/derefer_test.rs:5:13: 5:26
 +         _4 = &mut ((*_6).0: i32);        // scope 2 at $DIR/derefer_test.rs:5:13: 5:26
++         StorageDead(_6);                 // scope 3 at $DIR/derefer_test.rs:6:9: 6:10
           StorageLive(_5);                 // scope 3 at $DIR/derefer_test.rs:6:9: 6:10
 -         _5 = &mut ((*(_2.1: &mut (i32, i32))).1: i32); // scope 3 at $DIR/derefer_test.rs:6:13: 6:26
 +         StorageLive(_7);                 // scope 3 at $DIR/derefer_test.rs:6:13: 6:26
 +         _7 = move (_2.1: &mut (i32, i32)); // scope 3 at $DIR/derefer_test.rs:6:13: 6:26
 +         _5 = &mut ((*_7).1: i32);        // scope 3 at $DIR/derefer_test.rs:6:13: 6:26
++         StorageDead(_7);                 // scope 0 at $DIR/derefer_test.rs:2:11: 7:2
           _0 = const ();                   // scope 0 at $DIR/derefer_test.rs:2:11: 7:2
           StorageDead(_5);                 // scope 3 at $DIR/derefer_test.rs:7:1: 7:2
           StorageDead(_4);                 // scope 2 at $DIR/derefer_test.rs:7:1: 7:2
           StorageDead(_2);                 // scope 1 at $DIR/derefer_test.rs:7:1: 7:2
           StorageDead(_1);                 // scope 0 at $DIR/derefer_test.rs:7:1: 7:2
-+         StorageDead(_6);                 // scope 0 at $DIR/derefer_test.rs:7:2: 7:2
-+         StorageDead(_7);                 // scope 0 at $DIR/derefer_test.rs:7:2: 7:2
           return;                          // scope 0 at $DIR/derefer_test.rs:7:2: 7:2
 +     }
 + 

src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir

@@ -23,11 +23,11 @@ fn b(_1: &mut Box<T>) -> &mut T {
         StorageLive(_7);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _7 = move (*_4);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _6 = &mut (*_7);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
+        StorageDead(_7);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _5 = &mut (*_6);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _3 = &mut (*_5);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         StorageDead(_6);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         StorageDead(_5);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        StorageDead(_7);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _2 = &mut (*_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:8:5: 8:15
         StorageDead(_4);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:8:14: 8:15
         _0 = &mut (*_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:8:5: 8:15