Delete ConstDebugInfo pass

Author: scottmcm

compiler/rustc_mir_transform/src/const_debuginfo.rs

@@ -55,7 +55,6 @@ mod remove_place_mention;
 // This pass is public to allow external drivers to perform MIR cleanup
 mod add_subtyping_projections;
 pub mod cleanup_post_borrowck;
-mod const_debuginfo;
 mod copy_prop;
 mod coroutine;
 mod cost_checker;
@@ -595,7 +594,6 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
             &simplify::SimplifyLocals::AfterGVN,
             &dataflow_const_prop::DataflowConstProp,
             &single_use_consts::SingleUseConsts,
-            &const_debuginfo::ConstDebugInfo,
             &o1(simplify_branches::SimplifyConstCondition::AfterConstProp),
             &jump_threading::JumpThreading,
             &early_otherwise_branch::EarlyOtherwiseBranch,

compiler/rustc_mir_transform/src/lib.rs

@@ -1,5 +1,5 @@
-- // MIR for `main` before ConstDebugInfo
-+ // MIR for `main` after ConstDebugInfo
+- // MIR for `main` before SingleUseConsts
++ // MIR for `main` after SingleUseConsts
 
   fn main() -> () {
       let mut _0: ();
@@ -56,39 +56,53 @@
 
       bb0: {
           nop;
-          _1 = const 1_u8;
+-         _1 = const 1_u8;
           nop;
-          _2 = const 2_u8;
+-         _2 = const 2_u8;
           nop;
-          _3 = const 3_u8;
+-         _3 = const 3_u8;
++         nop;
++         nop;
++         nop;
           StorageLive(_4);
           StorageLive(_5);
           StorageLive(_6);
-          _6 = const 1_u8;
+-         _6 = const 1_u8;
++         nop;
           StorageLive(_7);
-          _7 = const 2_u8;
-          _5 = const 3_u8;
+-         _7 = const 2_u8;
+-         _5 = const 3_u8;
++         nop;
++         nop;
           StorageDead(_7);
           StorageDead(_6);
           StorageLive(_8);
-          _8 = const 3_u8;
-          _4 = const 6_u8;
+-         _8 = const 3_u8;
+-         _4 = const 6_u8;
++         nop;
++         nop;
           StorageDead(_8);
           StorageDead(_5);
           StorageLive(_9);
-          _9 = const "hello, world!";
+-         _9 = const "hello, world!";
++         nop;
           StorageLive(_10);
           _10 = (const true, const false, const 123_u32);
           StorageLive(_11);
-          _11 = const Option::<u16>::Some(99_u16);
+-         _11 = const Option::<u16>::Some(99_u16);
++         nop;
           StorageLive(_12);
-          _12 = const Point {{ x: 32_u32, y: 32_u32 }};
+-         _12 = const Point {{ x: 32_u32, y: 32_u32 }};
++         nop;
           StorageLive(_13);
           nop;
-          _14 = const 32_u32;
+-         _14 = const 32_u32;
++         nop;
           StorageLive(_15);
-          _15 = const 32_u32;
-          _13 = const 64_u32;
+-         _15 = const 32_u32;
+-         _13 = const 64_u32;
++         nop;
++         nop;
           StorageDead(_15);
           nop;
           _0 = const ();

tests/mir-opt/const_debuginfo.main.ConstDebugInfo.diff renamed to tests/mir-opt/const_debuginfo.main.SingleUseConsts.diff

@@ -1,12 +1,14 @@
-//@ test-mir-pass: ConstDebugInfo
+//@ test-mir-pass: SingleUseConsts
 //@ compile-flags: -C overflow-checks=no -Zmir-enable-passes=+GVN
 
+#![allow(unused)]
+
 struct Point {
     x: u32,
     y: u32,
 }
 
-// EMIT_MIR const_debuginfo.main.ConstDebugInfo.diff
+// EMIT_MIR const_debuginfo.main.SingleUseConsts.diff
 fn main() {
     // CHECK-LABEL: fn main(
     // CHECK: debug x => const 1_u8;

tests/mir-opt/const_debuginfo.rs

@@ -8,7 +8,7 @@
 +         let mut _2: bool;
 +         let mut _3: bool;
 +         scope 2 {
-+             debug buffer => const inner::promoted[0];
++             debug buffer => _1;
 +             scope 3 {
 +                 debug index => _0;
 +             }

tests/mir-opt/inline/issue_106141.outer.Inline.panic-abort.diff

@@ -8,7 +8,7 @@
 +         let mut _2: bool;
 +         let mut _3: bool;
 +         scope 2 {
-+             debug buffer => const inner::promoted[0];
++             debug buffer => _1;
 +             scope 3 {
 +                 debug index => _0;
 +             }