pkg/highway: expand detection to all platforms not just darwin

pkg/highway/src/cpp/targets.cpp

@@ -0,0 +1,61 @@
+#include <hwy/base.h>
+#include <hwy/detect_targets.h>
+#include <hwy/highway.h>
+#include <hwy/targets.h>
+
+namespace hwy {
+
+extern "C" int64_t ghostty_hwy_detect_targets();
+
+static int64_t DetectTargets() {
+  int64_t bits = HWY_SCALAR | HWY_EMU128;
+
+#if (HWY_ARCH_X86 || HWY_ARCH_ARM) && HWY_HAVE_RUNTIME_DISPATCH
+  bits |= ghostty_hwy_detect_targets();
+#else
+  bits |= HWY_ENABLED_BASELINE;
+#endif
+
+  if ((bits & HWY_ENABLED_BASELINE) != HWY_ENABLED_BASELINE) {
+    const uint64_t bits_u = static_cast<uint64_t>(bits);
+    const uint64_t enabled = static_cast<uint64_t>(HWY_ENABLED_BASELINE);
+    HWY_WARN("CPU supports 0x%08x%08x, software requires 0x%08x%08x\n",
+             static_cast<uint32_t>(bits_u >> 32),
+             static_cast<uint32_t>(bits_u & 0xFFFFFFFF),
+             static_cast<uint32_t>(enabled >> 32),
+             static_cast<uint32_t>(enabled & 0xFFFFFFFF));
+  }
+
+  return bits;
+}
+
+static int64_t supported_targets_for_test_ = 0;
+static int64_t supported_mask_ = LimitsMax<int64_t>();
+
+HWY_DLLEXPORT void DisableTargets(int64_t disabled_targets) {
+  supported_mask_ = static_cast<int64_t>(~disabled_targets);
+  GetChosenTarget().DeInit();
+}
+
+HWY_DLLEXPORT void SetSupportedTargetsForTest(int64_t targets) {
+  supported_targets_for_test_ = targets;
+  GetChosenTarget().DeInit();
+}
+
+HWY_DLLEXPORT int64_t SupportedTargets() {
+  int64_t targets = supported_targets_for_test_;
+  if (HWY_LIKELY(targets == 0)) {
+    targets = DetectTargets();
+    GetChosenTarget().Update(targets);
+  }
+
+  targets &= supported_mask_;
+  return targets == 0 ? HWY_STATIC_TARGET : targets;
+}
+
+HWY_DLLEXPORT ChosenTarget& GetChosenTarget() {
+  static ChosenTarget chosen_target;
+  return chosen_target;
+}
+
+}  // namespace hwy