[RELEASE ONLY CHANGES] Bump release version to 1.3.1 (#19818)

Updates the release branch version marker to 1.3.1 and refreshes the iOS
SwiftPM examples to use swiftpm-1.3.1.

Also fixes the Android APK test setup on the release branch by replacing
the expired fixed XNNPACK golden artifact URL with discovery of the
newest available golden artifact, and by making related downloads fail
fast with retries.

Test Plan:
- `git diff --check`
- `bash -n extension/android/executorch_android/android_test_setup.sh`
- Verified the golden artifact discovery logic finds
`golden_artifacts_26052719.zip`

This PR was authored with Claude.

Author: JacobSzwejbka

docs/source/getting-started.md

@@ -160,7 +160,7 @@ For a full example of running a model on Android, see the [DeepLabV3AndroidDemo]
 #### Installation
 ExecuTorch supports both iOS and macOS via C++, as well as hardware backends for CoreML, MPS, and CPU. The iOS runtime library is provided as a collection of .xcframework targets and are made available as a Swift PM package.
 
-To get started with Xcode, go to File > Add Package Dependencies. Paste the URL of the ExecuTorch repo into the search bar and select it. Make sure to change the branch name to the desired ExecuTorch version in format “swiftpm-”, (e.g. “swiftpm-1.3.0”).  The ExecuTorch dependency can also be added to the package file manually. See [Using ExecuTorch on iOS](using-executorch-ios.md) for more information.
+To get started with Xcode, go to File > Add Package Dependencies. Paste the URL of the ExecuTorch repo into the search bar and select it. Make sure to change the branch name to the desired ExecuTorch version in format “swiftpm-”, (e.g. “swiftpm-1.3.1”).  The ExecuTorch dependency can also be added to the package file manually. See [Using ExecuTorch on iOS](using-executorch-ios.md) for more information.
 
 #### Runtime APIs
 Models can be loaded and run from Objective-C using the C++ APIs.

docs/source/using-executorch-ios.md

@@ -28,7 +28,7 @@ The prebuilt ExecuTorch runtime, backend, and kernels are available as a [Swift
 
 #### Xcode
 
-In Xcode, go to `File > Add Package Dependencies`. Paste the URL of the [ExecuTorch repo](https://github.com/pytorch/executorch) into the search bar and select it. Make sure to change the branch name to the desired ExecuTorch version in format "swiftpm-<version>", (e.g. "swiftpm-1.3.0"), or a branch name in format "swiftpm-<version>.<year_month_date>" (e.g. "swiftpm-1.4.0-20260601") for a [nightly build](https://ossci-ios.s3.amazonaws.com/list.html) on a specific date.
+In Xcode, go to `File > Add Package Dependencies`. Paste the URL of the [ExecuTorch repo](https://github.com/pytorch/executorch) into the search bar and select it. Make sure to change the branch name to the desired ExecuTorch version in format "swiftpm-<version>", (e.g. "swiftpm-1.3.1"), or a branch name in format "swiftpm-<version>.<year_month_date>" (e.g. "swiftpm-1.4.0-20260601") for a [nightly build](https://ossci-ios.s3.amazonaws.com/list.html) on a specific date.
 
 ![](_static/img/swiftpm_xcode1.png)
 
@@ -61,7 +61,7 @@ let package = Package(
   ],
   dependencies: [
     // Use "swiftpm-<version>.<year_month_day>" branch name for a nightly build.
-    .package(url: "https://github.com/pytorch/executorch.git", branch: "swiftpm-1.3.0")
+    .package(url: "https://github.com/pytorch/executorch.git", branch: "swiftpm-1.3.1")
   ],
   targets: [
     .target(

extension/android/executorch_android/android_test_setup.sh

@@ -13,6 +13,10 @@ fi
 which "${PYTHON_EXECUTABLE}"
 
 BASEDIR=$(dirname "$(realpath $0)")
+DEFAULT_GOLDEN_ARTIFACTS_BASE_URL="https://gha-artifacts.s3.amazonaws.com/pytorch/executorch" # @lint-ignore
+DEFAULT_GOLDEN_ARTIFACTS_BASE_URL+="/test-backend-artifacts/golden-artifacts-xnnpack"
+GOLDEN_ARTIFACTS_BASE_URL="${GOLDEN_ARTIFACTS_BASE_URL:-${DEFAULT_GOLDEN_ARTIFACTS_BASE_URL}}"
+export GOLDEN_ARTIFACTS_BASE_URL
 
 prepare_xor() {
   pushd "${BASEDIR}/../../training/"
@@ -24,13 +28,58 @@ prepare_xor() {
 
 prepare_tinyllama() {
   local S3_BASE="https://ossci-android.s3.amazonaws.com/executorch/stories/snapshot-20260114"
-  curl -C - -Ls "${S3_BASE}/stories110M.pte" --output "${BASEDIR}/src/androidTest/resources/stories.pte"
-  curl -C - -Ls "${S3_BASE}/tokenizer.model" --output "${BASEDIR}/src/androidTest/resources/tokenizer.bin"
+  curl -fL --retry 3 --retry-all-errors -C - \
+    "${S3_BASE}/stories110M.pte" \
+    --output "${BASEDIR}/src/androidTest/resources/stories.pte"
+  curl -fL --retry 3 --retry-all-errors -C - \
+    "${S3_BASE}/tokenizer.model" \
+    --output "${BASEDIR}/src/androidTest/resources/tokenizer.bin"
+}
+
+find_latest_golden_artifacts_url() {
+  "${PYTHON_EXECUTABLE}" <<'PY'
+from datetime import datetime, timedelta, timezone
+import os
+import sys
+import urllib.error
+import urllib.request
+
+base_url = os.environ["GOLDEN_ARTIFACTS_BASE_URL"]
+lookback_days = int(os.environ.get("GOLDEN_ARTIFACT_LOOKBACK_DAYS", "14"))
+
+for hours_ago in range(lookback_days * 24):
+    timestamp = (datetime.now(timezone.utc) - timedelta(hours=hours_ago)).strftime(
+        "%y%m%d%H"
+    )
+    url = f"{base_url}/golden_artifacts_{timestamp}.zip"
+    request = urllib.request.Request(url, method="HEAD")
+    try:
+        with urllib.request.urlopen(request, timeout=10) as response:
+            if 200 <= response.status < 300:
+                print(url)
+                sys.exit(0)
+    except urllib.error.HTTPError as error:
+        if error.code not in (403, 404):
+            print(f"Skipping {url}: HTTP {error.code}", file=sys.stderr)
+    except Exception as error:
+        print(f"Skipping {url}: {error}", file=sys.stderr)
+
+print(
+    f"No XNNPACK golden artifact found under {base_url} from the last {lookback_days} days",
+    file=sys.stderr,
+)
+sys.exit(1)
+PY
 }
 
 prepare_golden() {
-  local url="https://gha-artifacts.s3.amazonaws.com/pytorch/executorch/test-backend-artifacts/golden-artifacts-xnnpack/golden_artifacts_26022500.zip"
-  curl -sL -o /tmp/golden.zip "$url"
+  local url="${GOLDEN_ARTIFACTS_URL:-}"
+  if [[ -z "${url}" ]]; then
+    url=$(find_latest_golden_artifacts_url)
+  fi
+  echo "Downloading XNNPACK golden artifacts from ${url}"
+  rm -rf /tmp/golden /tmp/golden.zip
+  curl -fL --retry 3 --retry-all-errors -o /tmp/golden.zip "$url"
   unzip -o /tmp/golden.zip -d /tmp/golden/
   for model in mobilenet_v2 vit_b_16; do
     cp "/tmp/golden/xnnpack/${model}.pte" "${BASEDIR}/src/androidTest/resources/"

version.txt

@@ -1 +1 @@
-1.3.0
+1.3.1