[CPU] Add support for parsing AArch64 cpu features. (iree-org#19881)

A step towards iree-org#19873

---------

Signed-off-by: hanhanW <hanhan0912@gmail.com>
Signed-off-by: Hyunsung Lee <ita9naiwa@gmail.com>

compiler/plugins/target/LLVMCPU/ResolveCPUAndCPUFeatures.cpp

@@ -6,6 +6,7 @@
 
 #include "compiler/plugins/target/LLVMCPU/ResolveCPUAndCPUFeatures.h"
 
+#include "llvm/TargetParser/AArch64TargetParser.h"
 #include "llvm/TargetParser/Host.h"
 #include "llvm/TargetParser/RISCVTargetParser.h"
 #include "llvm/TargetParser/SubtargetFeature.h"
@@ -61,6 +62,14 @@ resolveCPUFeaturesForCPU(const llvm::Triple &triple, std::string &cpu,
   } else if (triple.isRISCV64()) {
     llvm::SmallVector<std::string> cpuFeatureList;
     addCpuFeatures(llvm::RISCV::getFeaturesForCPU, cpuFeatureList);
+  } else if (triple.isAArch64()) {
+    std::vector<llvm::StringRef> cpuFeatureList;
+    const llvm::AArch64::ArchInfo *cpuArch = llvm::AArch64::getArchForCpu(cpu);
+    llvm::AArch64::getExtensionFeatures(cpuArch->DefaultExts, cpuFeatureList);
+    targetCpuFeatures.AddFeature(cpuArch->ArchFeature);
+    for (const auto &feature : cpuFeatureList) {
+      targetCpuFeatures.AddFeature(feature);
+    }
   } else {
     return ResolveCPUAndCPUFeaturesStatus::UnimplementedMapping;
   }