From 92a993683a817dc76d62ee3f53ad2dfac82a6afd Mon Sep 17 00:00:00 2001
From: Larry Ewing <lewing@microsoft.com>
Date: Wed, 19 Feb 2025 15:27:37 -0600
Subject: [PATCH] Revert "[browser][MT] move wasm MT CI legs to extra-platforms
 (#112690)"

This reverts commit 3c97a9040833ab190961e37a86ce5073a932ed9b.
---
 .../runtime-extra-platforms-wasm.yml          | 17 +------------
 eng/pipelines/runtime.yml                     | 25 +++++++++++++++++++
 src/mono/wasm/features.md                     |  2 +-
 3 files changed, 27 insertions(+), 17 deletions(-)

diff --git a/eng/pipelines/extra-platforms/runtime-extra-platforms-wasm.yml b/eng/pipelines/extra-platforms/runtime-extra-platforms-wasm.yml
index dd7f5d2a638203..f0b197b68db9ac 100644
--- a/eng/pipelines/extra-platforms/runtime-extra-platforms-wasm.yml
+++ b/eng/pipelines/extra-platforms/runtime-extra-platforms-wasm.yml
@@ -74,22 +74,6 @@ jobs:
       scenarios:
         - WasmTestOnChrome
 
-  # Library tests with full threading
-  - template: /eng/pipelines/common/templates/wasm-library-tests.yml
-    parameters:
-      platforms:
-        - browser_wasm
-        #- browser_wasm_win
-      nameSuffix: _Threading
-      extraBuildArgs: /p:WasmEnableThreads=true /p:AotHostArchitecture=x64 /p:AotHostOS=$(_hostedOS)
-      extraHelixArguments: /p:WasmEnableThreads=true
-      isExtraPlatformsBuild: ${{ parameters.isExtraPlatformsBuild }}
-      isWasmOnlyBuild: ${{ parameters.isWasmOnlyBuild }}
-      alwaysRun: ${{ parameters.isWasmOnlyBuild }}
-      shouldRunSmokeOnly: onLibrariesAndIllinkChanges
-      scenarios:
-        - WasmTestOnChrome
-
   # EAT Library tests - only run on linux
   - template: /eng/pipelines/common/templates/wasm-library-aot-tests.yml
     parameters:
@@ -178,6 +162,7 @@ jobs:
         - browser_wasm_win
       nameSuffix: MultiThreaded
       extraBuildArgs: /p:WasmEnableThreads=true /p:AotHostArchitecture=x64 /p:AotHostOS=$(_hostedOS)
+      condition: ne(variables['wasmMultiThreadedBuildOnlyNeededOnDefaultPipeline'], true)
       publishArtifactsForWorkload: true
       publishWBT: false
 
diff --git a/eng/pipelines/runtime.yml b/eng/pipelines/runtime.yml
index 7514379d672533..4880c8475743da 100644
--- a/eng/pipelines/runtime.yml
+++ b/eng/pipelines/runtime.yml
@@ -822,6 +822,20 @@ extends:
           scenarios:
             - WasmTestOnChrome
 
+      # Library tests with full threading
+      - template: /eng/pipelines/common/templates/wasm-library-tests.yml
+        parameters:
+          platforms:
+            - browser_wasm
+            #- browser_wasm_win
+          nameSuffix: _Threading
+          extraBuildArgs: /p:WasmEnableThreads=true /p:AotHostArchitecture=x64 /p:AotHostOS=$(_hostedOS)
+          extraHelixArguments: /p:WasmEnableThreads=true
+          alwaysRun: ${{ variables.isRollingBuild }}
+          shouldRunSmokeOnly: onLibrariesAndIllinkChanges
+          scenarios:
+            - WasmTestOnChrome
+
       # EAT Library tests - only run on linux
       - template: /eng/pipelines/common/templates/wasm-library-aot-tests.yml
         parameters:
@@ -857,6 +871,17 @@ extends:
           publishArtifactsForWorkload: true
           publishWBT: true
 
+      - template: /eng/pipelines/common/templates/wasm-build-only.yml
+        parameters:
+          platforms:
+            - browser_wasm
+            - browser_wasm_win
+          condition: or(eq(variables.isRollingBuild, true), eq(variables.wasmSingleThreadedBuildOnlyNeededOnDefaultPipeline, true))
+          nameSuffix: MultiThreaded
+          extraBuildArgs: /p:WasmEnableThreads=true /p:AotHostArchitecture=x64 /p:AotHostOS=$(_hostedOS)
+          publishArtifactsForWorkload: true
+          publishWBT: false
+
       # Browser Wasm.Build.Tests
       - template: /eng/pipelines/common/templates/browser-wasm-build-tests.yml
         parameters:
diff --git a/src/mono/wasm/features.md b/src/mono/wasm/features.md
index ec00eff02e3d6a..c13dde952952c9 100644
--- a/src/mono/wasm/features.md
+++ b/src/mono/wasm/features.md
@@ -23,7 +23,7 @@ Some of these properties require a unique build of the runtime, which means that
 
 ### Multi-threading
 
-Multi-threading experiment is enabled by `<WasmEnableThreads>true</WasmEnableThreads>`, and is currently disabled by default. It requires a unique build of the runtime.
+Multi-threading support is enabled by `<WasmEnableThreads>true</WasmEnableThreads>`, and is currently disabled by default. It requires a unique build of the runtime.
 
 Your HTTPS server and/or proxy must be configured to send HTTP headers similar to `Cross-Origin-Embedder-Policy:require-corp` and `Cross-Origin-Opener-Policy:same-origin` in order to enable multi-threading support in end-user web browsers for security reasons.