Further reduce work load for Mac CI pipeline

.github/workflows/mac.yml

@@ -21,6 +21,12 @@ env:
 jobs:
   cpu:
     uses: ./.github/workflows/macos-ci-build-and-test-workflow.yml
+    with:
+      # Only build arm64 for CPU
+      matrix_exclude: >-
+        [
+          {"platform_machine": "x86_64"}
+        ]
 
   coreml:
     uses: ./.github/workflows/macos-ci-build-and-test-workflow.yml
@@ -31,6 +37,12 @@ jobs:
     uses: ./.github/workflows/macos-ci-build-and-test-workflow.yml
     with:
       use_xnnpack: true
+      # only build arm64/Debug for XNNPack
+      matrix_exclude: >-
+        [
+          {"platform_machine": "x86_64"},
+          {"platform_machine": "arm64", "build_config": "Release"}
+        ]
 
   webgpu:
     uses: ./.github/workflows/macos-ci-build-and-test-workflow.yml

.github/workflows/macos-ci-build-and-test-workflow.yml

@@ -20,28 +20,26 @@ on:
         required: false
         type: string
         default: "3.11"
+      matrix_exclude:
+        required: false
+        type: string
+        description: "JSON string specifying combinations to exclude from the matrix"
+        # we do not have enough resources to run all combinations
+        # Exclude x86_64 + Debug combination by default
+        default: >-
+          [
+            {"platform_machine": "x86_64", "build_config": "Debug"}
+          ]
 
 jobs:
   build-and-test:
     strategy:
       matrix:
         platform_machine: ["x86_64", "arm64"]
         build_config: ["Debug", "Release"]
-        exclude:
-          # we do not have enough resources to run all combinations
-          # Exclude x86_64 + Debug combination
-          - platform_machine: "x86_64"
-            build_config: "Debug"
-        include:
-          - platform_machine: "x86_64"
-            runs_on: "macos-13"
-            xcode_version: "14.3.1"
-          - platform_machine: "arm64"
-            runs_on: "macos-15"
-            xcode_version: "16"
-      max-parallel: 1
+        exclude: ${{ fromJSON(inputs.matrix_exclude) }}
 
-    runs-on: ${{ matrix.runs_on }}
+    runs-on: ${{ matrix.platform_machine == 'x86_64' && 'macos-13' || 'macos-15' }}
     env:
       build_flags: >
         --build_dir ./build
@@ -58,6 +56,7 @@ jobs:
         ${{ inputs.use_coreml && '--use_coreml' || '' }}
         --use_vcpkg --use_vcpkg_ms_internal_asset_cache
         --config ${{ matrix.build_config }}
+      xcode_version: ${{ matrix.platform_machine == 'x86_64' && '14.3.1' || '16' }}
 
     steps:
       - name: Checkout code
@@ -68,7 +67,7 @@ jobs:
         with:
           platform_machine: ${{ matrix.platform_machine }}
           python_version: ${{ inputs.python_version }}
-          xcode_version: ${{ matrix.xcode_version }}
+          xcode_version: ${{ env.xcode_version }}
           use_cache: true
 
       - uses: actions/cache@v3