Auto merge of #99780 - Nilstrieb:mir-opt-test-line-no, r=oli-obk

Use line numbers relative to the function in mir-opt tests

As shown in #99770, the line numbers can be a big source of needless and confusing diffs. This PR adds a new flag `-Zmir-pretty-relative-line-numbers` to make them relative to the function declaration, which avoids most needless diffs from attribute changes.

`@JakobDegen` told me that there has been a zulip conversation about disabling line numbers with mixed opinions, so I'd like to get some feedback here, for this hopefully better solution.

r? rust-lang/wg-mir-opt

1 files changed, 20 insertions, 20 deletions

diff --git a/src/test/mir-opt/simplify_locals.c.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.c.SimplifyLocals.diff
index dd2d7954961..5d7517e4eb4 100644
--- a/src/test/mir-opt/simplify_locals.c.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.c.SimplifyLocals.diff
@@ -2,32 +2,32 @@
 + // MIR for `c` after SimplifyLocals
   
   fn c() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:13:8: 13:8
-      let _1: [u8; 10];                    // in scope 0 at $DIR/simplify-locals.rs:14:9: 14:14
--     let mut _2: &[u8];                   // in scope 0 at $DIR/simplify-locals.rs:16:20: 16:26
--     let mut _3: &[u8; 10];               // in scope 0 at $DIR/simplify-locals.rs:16:20: 16:26
--     let _4: &[u8; 10];                   // in scope 0 at $DIR/simplify-locals.rs:16:20: 16:26
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:8: +0:8
+      let _1: [u8; 10];                    // in scope 0 at $DIR/simplify-locals.rs:+1:9: +1:14
+-     let mut _2: &[u8];                   // in scope 0 at $DIR/simplify-locals.rs:+3:20: +3:26
+-     let mut _3: &[u8; 10];               // in scope 0 at $DIR/simplify-locals.rs:+3:20: +3:26
+-     let _4: &[u8; 10];                   // in scope 0 at $DIR/simplify-locals.rs:+3:20: +3:26
       scope 1 {
-          debug bytes => _1;               // in scope 1 at $DIR/simplify-locals.rs:14:9: 14:14
+          debug bytes => _1;               // in scope 1 at $DIR/simplify-locals.rs:+1:9: +1:14
           scope 2 {
           }
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:14:9: 14:14
-          _1 = [const 0_u8; 10];           // scope 0 at $DIR/simplify-locals.rs:14:17: 14:26
--         StorageLive(_2);                 // scope 1 at $DIR/simplify-locals.rs:16:20: 16:26
--         StorageLive(_3);                 // scope 1 at $DIR/simplify-locals.rs:16:20: 16:26
--         StorageLive(_4);                 // scope 1 at $DIR/simplify-locals.rs:16:20: 16:26
--         _4 = &_1;                        // scope 1 at $DIR/simplify-locals.rs:16:20: 16:26
--         _3 = &(*_4);                     // scope 1 at $DIR/simplify-locals.rs:16:20: 16:26
--         _2 = move _3 as &[u8] (Pointer(Unsize)); // scope 1 at $DIR/simplify-locals.rs:16:20: 16:26
--         StorageDead(_3);                 // scope 1 at $DIR/simplify-locals.rs:16:25: 16:26
--         StorageDead(_4);                 // scope 1 at $DIR/simplify-locals.rs:16:26: 16:27
--         StorageDead(_2);                 // scope 1 at $DIR/simplify-locals.rs:16:26: 16:27
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:13:8: 17:2
-          StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:17:1: 17:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:17:2: 17:2
+          StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:+1:9: +1:14
+          _1 = [const 0_u8; 10];           // scope 0 at $DIR/simplify-locals.rs:+1:17: +1:26
+-         StorageLive(_2);                 // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
+-         StorageLive(_3);                 // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
+-         StorageLive(_4);                 // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
+-         _4 = &_1;                        // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
+-         _3 = &(*_4);                     // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
+-         _2 = move _3 as &[u8] (Pointer(Unsize)); // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
+-         StorageDead(_3);                 // scope 1 at $DIR/simplify-locals.rs:+3:25: +3:26
+-         StorageDead(_4);                 // scope 1 at $DIR/simplify-locals.rs:+3:26: +3:27
+-         StorageDead(_2);                 // scope 1 at $DIR/simplify-locals.rs:+3:26: +3:27
+          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:8: +4:2
+          StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/simplify-locals.rs:+4:2: +4:2
       }
   }