chore: import upstream snapshot with attribution

third_party/kissfft/BUILD

@@ -0,0 +1,3 @@
+# This empty BUILD file is required to make Bazel treat this directory as a package.
+
+# copybara:uncomment package(default_applicable_licenses = ["//tensorflow:license"])

third_party/kissfft/kissfft.BUILD

@@ -0,0 +1,30 @@
+package(
+    default_visibility = ["//visibility:public"],
+)
+
+licenses(["notice"])  # Apache 2.0
+
+exports_files(["COPYING"])
+
+cc_library(
+    name = "kiss_fftr_16",
+    srcs = [
+        "kfc.c",
+        "kiss_fft.c",
+        "kiss_fftnd.c",
+        "kiss_fftndr.c",
+        "kiss_fftr.c",
+    ],
+    hdrs = [
+        "_kiss_fft_guts.h",
+        "kfc.h",
+        "kiss_fft.h",
+        "kiss_fft_log.h",
+        "kiss_fftnd.h",
+        "kiss_fftndr.h",
+        "kiss_fftr.h",
+    ],
+    copts = [
+        "-DFIXED_POINT=16",
+    ],
+)

third_party/kissfft/workspace.bzl

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+"""Loads the kissfft library, used by TF Lite."""
+
+load("//third_party:repo.bzl", "tf_http_archive", "tf_mirror_urls")
+
+def repo():
+    tf_http_archive(
+        name = "kissfft",
+        strip_prefix = "kissfft-131.1.0",
+        sha256 = "76c1aac87ddb7258f34b08a13f0eebf9e53afa299857568346aa5c82bcafaf1a",
+        urls = tf_mirror_urls("https://github.com/mborgerding/kissfft/archive/refs/tags/131.1.0.tar.gz"),
+        build_file = "//third_party/kissfft:kissfft.BUILD",
+    )