Delete GT_ADDR

[SingleAccretion]

The real work has at this point been done, so this just deletes the oper and its last use as a sentinel. No diffs.

Some TODO-ADDRs in source still remain, but they can be addressed separately.

Closes #11057.

With this legacy IR construct gone, let's see how much time will it take to delete its ASG cousin :).

[ghost]

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Issue Details

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The real work has at this point been done, so this just deletes the oper and its last use as a sentinel.

Some TODO-ADDRs in source still remain, but they can be addresses separately.

Closes #11057. No diffs expected.

With one legacy IR construct gone, let's see how much time will it take to delete its ASG cousin :).

Depends on #79722.

Author:	SingleAccretion
Assignees:	-
Labels:	area-CodeGen-coreclr, community-contribution
Milestone:	-

[AndyAyersMS]

And they said this day would never come...

Glad to see this at long last.

[SingleAccretion]

@dotnet/jit-contrib

[EgorBo]

will leave it open for someone else to take another look

[am11]

Congrats! 🎉

@SingleAccretion, design docs also mention GT_ADDR in a few places:

$ git grep GT_ADDR
docs/design/coreclr/jit/ryujit-overview.md:| [Rationalization](#rationalization) | Flowgraph order changes from `FGOrderTree` to `FGOrderLinear`. All `GT_COMMA`, `GT_ASG` and `GT_ADDR` nodes are transformed. |
docs/design/coreclr/jit/ryujit-overview.md:* Elimination of address nodes (`GT_ADDR`). These are problematic because of the need for parent context to analyze the child.
docs/design/coreclr/jit/ryujit-overview.md:  * All `GT_ADDR` nodes are eliminated (e.g. with `GT_LCL_VAR_ADDR`).
docs/design/coreclr/jit/ryujit-tutorial.md:    - Eliminate GT_ADDR: Need parent context to analyze child
docs/design/coreclr/jit/ryujit-tutorial.md:We would like to ensure that all data flows are from child to parent. Examples where this is currently violated are in the assignment, or GT_ASG node, where the data flows from the right hand side of the assignment "over" the parent assignment, to the value being defined on the left hand side. Similarly, the child of a GT_ADDR node may appear to be a use or a definition of the value, when instead its address is being taken.
docs/design/coreclr/jit/ryujit-tutorial.md:- All GT_ADDR nodes are eliminated (e.g. with GT_LCL_VAR_ADDR)

[SingleAccretion]

Thank you :). ADDR is not the only obsolete concept they mention - #69988.