Rollup merge of #61532 - wesleywiser:const_prop_more, r=oli-obk

[const-prop] Support Rvalue::{Ref,Len} and Deref

Also fixes an ICE I found in testing.

r? @oli-obk

~~The final commit is just for a perf run. I'll remove it after that is completed.~~

src/test/ui/consts/const-eval/promoted_errors.stderr

@@ -16,6 +16,12 @@ warning: attempt to divide by zero
 LL |     println!("{}", 1/(1-1));
    |                    ^^^^^^^
 
+warning: this expression will panic at runtime
+  --> $DIR/promoted_errors.rs:9:20
+   |
+LL |     println!("{}", 1/(1-1));
+   |                    ^^^^^^^ attempt to divide by zero
+
 warning: attempt to divide by zero
   --> $DIR/promoted_errors.rs:11:14
    |
@@ -34,6 +40,12 @@ warning: attempt to divide by zero
 LL |     println!("{}", 1/(false as u32));
    |                    ^^^^^^^^^^^^^^^^
 
+warning: this expression will panic at runtime
+  --> $DIR/promoted_errors.rs:14:20
+   |
+LL |     println!("{}", 1/(false as u32));
+   |                    ^^^^^^^^^^^^^^^^ attempt to divide by zero
+
 warning: attempt to divide by zero
   --> $DIR/promoted_errors.rs:16:14
    |