Reapply "Create a single copy of stub templates

[davidwrighton]

Revert PR #115665 which reverted #114462

• And disable feature on Apple platforms until Fix enumerating loaded process modules on Apple platforms diagnostics#5487 is merged and generally available.

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[Copilot]

Pull Request Overview

This PR reverts previous changes that affected the creation of a single copy of stub templates and disables the feature on Apple platforms pending resolution of dotnet/diagnostics#5487.

• Reintroduces changes to use standard integer types (uint8_t and size_t) in function signatures.
• Integrates a new configuration structure (InterleavedLoaderHeapConfig) for loader heap initialization and code page generation.
• Disables the template mapping feature on Apple platforms and adds related conditional logic.

Reviewed Changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/coreclr/vm/precode.h / precode.cpp	Updated function signatures to use uint8_t* and size_t for improved clarity and consistency.
src/coreclr/vm/loaderallocator.cpp	Replacing function pointer parameters with references to InterleavedLoaderHeapConfig for stub code page generation.
src/coreclr/utilcode/interleavedloaderheap.cpp	Updated allocation paths to support template-based thunk allocation and proper configuration initialization.
src/coreclr/inc/loaderheap.h	Added and updated the configuration structure and its usage in loader heap initialization.
Other files	Adjustments in assembly and executable allocator files to integrate template-based thunk allocation.

Comments suppressed due to low confidence (3)

src/coreclr/utilcode/interleavedloaderheap.cpp:542

• The integration of the new InterleavedLoaderHeapConfig and its initialization via CreateTemplate appears correct. Please ensure that the template-based allocation paths are covered by adequate tests to validate the behavior under both standard and template-enabled environments.

void InitializeLoaderHeapConfig(InterleavedLoaderHeapConfig *pConfig, size_t stubSize, void* templateInImage, void (*codePageGenerator)(uint8_t* pageBase, uint8_t* pageBaseRX, size_t size))

src/coreclr/vm/precode.h:228

• Changing function signatures from BYTE* and SIZE_T to uint8_t* and size_t improves type clarity and portability. Please ensure that all related pointer arithmetic and casting remain consistent across the codebase.

static void GenerateCodePage(uint8_t* pageBase, uint8_t* pageBaseRX, size_t size);

src/coreclr/vm/loaderallocator.cpp:1211

• Replacing the original code page generator function pointer with a reference to the global configuration ensures a centralized management approach. Verify that all caller sites of the loader heap allocation have been updated to work with the new configuration structure.

&s_stubPrecodeHeapConfig

[thaystg]

I think we need to merge and release dbgshim, then bump it everywhere and then merge here. What do you think @tommcdon @davidwrighton ?

[thaystg]

Ah okay, we should enable on Mac after doing what I asked :)

[tommcdon]

Left a minor comment change for your review

[davidwrighton]

/ba-g The build break is unrelated and has already been fixed by #115767