enable hardware intrinsics for libaom

src/SPC/builder/unix/library/libaom.php

@@ -7,6 +7,7 @@ namespace SPC\builder\unix\library;
 use SPC\toolchain\ToolchainManager;
 use SPC\toolchain\ZigToolchain;
 use SPC\util\executor\UnixCMakeExecutor;
+use SPC\util\SPCTarget;
 
 trait libaom
 {
@@ -17,9 +18,16 @@ trait libaom
             $new = trim($extra . ' -D_GNU_SOURCE');
             f_putenv("SPC_COMPILER_EXTRA={$new}");
         }
+        $targetCpu = SPCTarget::getTargetArch();
+        if (str_starts_with($targetCpu, 'aarch')) {
+            $targetCpu = str_replace($targetCpu, 'aarch', 'arm');
+        }
         UnixCMakeExecutor::create($this)
             ->setBuildDir("{$this->source_dir}/builddir")
-            ->addConfigureArgs('-DAOM_TARGET_CPU=generic')
+            ->addConfigureArgs(
+                "-DAOM_TARGET_CPU={$targetCpu}",
+                '-DCONFIG_RUNTIME_CPU_DETECT=1'
+            )
             ->build();
         f_putenv("SPC_COMPILER_EXTRA={$extra}");
         $this->patchPkgconfPrefix(['aom.pc']);

src/SPC/util/SPCTarget.php

@@ -127,4 +127,19 @@ class SPCTarget
             default => PHP_OS_FAMILY,
         };
     }
+
+    /**
+     * Returns the target OS arch, e.g. x86_64, aarch64, arm, x86.
+     */
+    public static function getTargetArch(): string
+    {
+        $target = (string) getenv('SPC_TARGET');
+        return match (true) {
+            str_starts_with($target, 'aarch64') => 'aarch64',
+            str_starts_with($target, 'arm-') => 'arm',
+            str_starts_with($target, 'x86_64-') => 'x86_64',
+            str_starts_with($target, 'x86-') => 'x86',
+            default => GNU_ARCH,
+        };
+    }
 }