From 55a6fed35ec2c8a234784726c16e8c19b2fd0434 Mon Sep 17 00:00:00 2001
From: Han-Chung Wang <hanhan0912@gmail.com>
Date: Mon, 3 Feb 2025 09:17:57 -0800
Subject: [PATCH] [CPU] Add support for parsing AArch64 cpu features. (#19881)

A step towards https://github.com/iree-org/iree/issues/19873

---------

Signed-off-by: hanhanW <hanhan0912@gmail.com>
Signed-off-by: Hyunsung Lee <ita9naiwa@gmail.com>
---
 .../plugins/target/LLVMCPU/ResolveCPUAndCPUFeatures.cpp  | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/compiler/plugins/target/LLVMCPU/ResolveCPUAndCPUFeatures.cpp b/compiler/plugins/target/LLVMCPU/ResolveCPUAndCPUFeatures.cpp
index 552b0b5621464..5850be4babba4 100644
--- a/compiler/plugins/target/LLVMCPU/ResolveCPUAndCPUFeatures.cpp
+++ b/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;
   }