[wasm] Align the runtime-test call-helper generator override

[radekdoulik]

Addresses review feedback on #131877.

Use PortableCallHelpersGeneratorPath for runtime-test corerun generation and diagnostics, matching browser/WASI app builds. Keep the existing in-repo generator fallback.

Validation

Seven target-level cases covered override precedence, fallback resolution, and diagnostics. Built a test-specific corerun and ran the native NestedStruct test on browser-wasm.

Note

This PR description was drafted with GitHub Copilot.

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[Copilot]

🟢 Approval recommended

The change is localized and consistent with existing browser/WASI targets; only a minor diagnostic ordering nit was found.

Pull request overview

Updates the WASM runtime-test corerun call-helper generation to use the shared PortableCallHelpersGeneratorPath MSBuild property (consistent with browser/WASI CoreCLR app builds), while retaining the in-repo Crossgen2InBuildDir fallback.

Changes:

• Switch generator path override from a private _WasmCorerunGeneratorPath to $(PortableCallHelpersGeneratorPath).
• Update diagnostics and execution (<Exec>) to reference PortableCallHelpersGeneratorPath.
• Keep the in-repo resolution fallback via $(Crossgen2InBuildDir).

File summaries

File	Description
src/tests/Common/CLRTest.WasmCorerun.targets	Use PortableCallHelpersGeneratorPath for generating portable call helpers during test-specific corerun generation, with updated error messages and Exec invocation.

Review details

• Files reviewed: 1/1 changed files
• Comments generated: 1
• Review effort level: Lite

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Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
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[Copilot]

🟡 Changes recommended

Renaming the MSBuild override property from $(PortableCallHelpersGeneratorPath) to $(Crossgen2Path) risks breaking existing out-of-repo builds unless a compatibility alias is retained.

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Review details

• Files reviewed: 3/3 changed files
• Comments generated: 2
• Review effort level: Lite

[Copilot]

🔵 Needs a closer look

The property rename removes prior override entry points (e.g., PortableCallHelpersGeneratorPath / _WasmCorerunGeneratorPath) without a compatibility alias, which can break existing build/test customization.

Review details

Suppressed comments (3)

Previously missed (1) — in code that hasn't changed since the last review.

src/tests/Common/CLRTest.WasmCorerun.targets:327

• This removes the _WasmCorerunGeneratorPath override point and switches to $(Crossgen2Path). If any existing infra is setting _WasmCorerunGeneratorPath (the previous error text suggested it was meant to be configurable), this will stop working. Consider treating _WasmCorerunGeneratorPath as a legacy alias when Crossgen2Path is not set.

src/mono/browser/build/BrowserWasmApp.CoreCLR.targets:703

• This change removes the previously supported $(PortableCallHelpersGeneratorPath) override and only honors $(Crossgen2Path). If any consumers (or existing build scripts) still set PortableCallHelpersGeneratorPath, the override will silently stop working. Consider mapping PortableCallHelpersGeneratorPath into Crossgen2Path as a backwards-compatible alias (with Crossgen2Path taking precedence).

      <_Crossgen2ExeSuffix Condition="'$(OS)' == 'Windows_NT'">.exe</_Crossgen2ExeSuffix>
      <Crossgen2Path Condition="'$(Crossgen2Path)' == '' and '$(Crossgen2InBuildDir)' != ''">$([MSBuild]::NormalizePath('$(Crossgen2InBuildDir)', 'crossgen2$(_Crossgen2ExeSuffix)'))</Crossgen2Path>
      <Crossgen2Path Condition="'$(Crossgen2Path)' == ''">$(Crossgen2ToolPath)</Crossgen2Path>

src/mono/wasi/build/WasiApp.CoreCLR.targets:163

• This renames the crossgen2 override property from $(PortableCallHelpersGeneratorPath) to $(Crossgen2Path) (and removes the former). If PortableCallHelpersGeneratorPath has existing consumers, this is a breaking change. Consider honoring PortableCallHelpersGeneratorPath as an alias when Crossgen2Path is not set.

      <_Crossgen2ExeSuffix Condition="'$(OS)' == 'Windows_NT'">.exe</_Crossgen2ExeSuffix>
      <Crossgen2Path Condition="'$(Crossgen2Path)' == '' and '$(Crossgen2InBuildDir)' != ''">$([MSBuild]::NormalizePath('$(Crossgen2InBuildDir)', 'crossgen2$(_Crossgen2ExeSuffix)'))</Crossgen2Path>
      <Crossgen2Path Condition="'$(Crossgen2Path)' == ''">$(Crossgen2ToolPath)</Crossgen2Path>

• Files reviewed: 3/3 changed files
• Comments generated: 0 new
• Review effort level: Lite