Fix issue #32466

[briansull]

Fixes outerloop leg: R2R Windows_NT x86 Checked no_tiered_compilation @ Windows.10.Amd64.Open

Fixes issue #32466

[BruceForstall]

@dotnet/jit-contrib

[CarolEidt]

Nit: With this change, it's not entirely clear that this comment is an extension of the previous comment. Also, while you're here, the previous comment isn't clear about whether this is a statement (i.e. restating the condition of the assert), or describing a condition, e.g. the if statement below).
Could you reword this as a complete statement? Perhaps:

// If we reach here, either:
// - we are not generating relocatable code,
// - the base address is a handle for an integer constant,
// - the base address is a constant zero (which doesn't require a reloc), or
// - the base address is a constant that fits into the memory instruction (this can happen on x86).
//   This last case is captured in the FitsInAddrBase method which is used by Lowering to determine that it can
//   be contained.

Of course, please correct if the above is not correct.

[briansull]

OK can change the comment.

I didn't like the existing comment, It isn't clear to me why we are testing a different set of invariants here than we when originally set the contained flag. And actually all 31 bit constants don't require a relocation, not just zero (for both x84 and x86)

[briansull]

I will use your comment and omit this part (which doesn't require a reloc)

[briansull]

OK, I changed it to:

        // If we reach here, either:
        // - we are not generating relocatable code, (typically the non-AOT JIT case)
        // - the base address is a handle represented by an integer constant,
        // - the base address is a constant zero, or
        // - the base address is a constant that fits into the memory instruction (this can happen on x86).
        //   This last case is captured in the FitsInAddrBase method which is used by Lowering to determine that it can
        //   be contained.
        //

[CarolEidt]

Great, thanks!

[CarolEidt]

LGTM

[briansull]

The last update to this assert was this:

Author: Bruce Forstall <brucefo@microsoft.com>
Date:   Thu Sep 8 16:42:22 2016 -0700

    Fix dotnet/coreclr#7100

    This issue is the following assert:
    ```
    Assert failure '!emitComp->opts.compReloc || memBase->IsIconHandle()'
    ```
    while ngen'ing mscorlib on desktop.

    We're trying to generate
    ```
    cmp ebx, dword ptr [0000H]
    ```
    (due to inlining). But, emitInsBinary() doesn't expect a zero address that
    is not a relocatable handle.

    Simply change the assert to allow this. The code then generates the correct
    zero base address.


    Commit migrated from https://github.com/dotnet/coreclr/commit/08f3ae19c6e07e6772ace96706012ed87e4e6f2e

[sandreenko]

LGTM, thank you