Add FreeBSD Arm64 support

BUILD.bazel

@@ -2,7 +2,7 @@
 
 load("@bazel_skylib//lib:selects.bzl", "selects")
 load("//:bazel/platforms.bzl", "PLATFORM_CPU_ARM", "PLATFORM_CPU_ARM64", "PLATFORM_CPU_MIPS", "PLATFORM_CPU_PPC", "PLATFORM_CPU_RISCV32", "PLATFORM_CPU_RISCV64", "PLATFORM_CPU_X86_64")
-load("//:bazel/platforms.bzl", "PLATFORM_OS_MACOS")
+load("//:bazel/platforms.bzl", "PLATFORM_OS_MACOS", "PLATFORM_OS_LINUX", "PLATFORM_OS_FREEBSD", "PLATFORM_OS_ANDROID")
 
 package(
     default_visibility = ["//visibility:public"],
@@ -169,11 +169,18 @@ cc_library(
 
 cc_library(
     name = "hwcaps",
-    srcs = ["src/hwcaps.c"],
+    srcs = [
+        "src/hwcaps.c",
+        "src/hwcaps_freebsd.c",
+        "src/hwcaps_linux_or_android.c",
+    ],
     copts = C99_FLAGS,
     defines = selects.with_or({
         PLATFORM_OS_MACOS: ["HAVE_DLFCN_H"],
-        "//conditions:default": ["HAVE_STRONG_GETAUXVAL"],
+        PLATFORM_OS_FREEBSD: ["HAVE_STRONG_ELF_AUX_INFO"],
+        PLATFORM_OS_LINUX: ["HAVE_STRONG_GETAUXVAL"],
+        PLATFORM_OS_ANDROID: ["HAVE_STRONG_GETAUXVAL"],
+        "//conditions:default": [],
     }),
     includes = INCLUDES,
     textual_hdrs = ["include/internal/hwcaps.h"],
@@ -189,6 +196,8 @@ cc_library(
     testonly = 1,
     srcs = [
         "src/hwcaps.c",
+        "src/hwcaps_freebsd.c",
+        "src/hwcaps_linux_or_android.c",
         "test/hwcaps_for_testing.cc",
     ],
     hdrs = [
@@ -218,9 +227,11 @@ cc_library(
         ],
         PLATFORM_CPU_ARM: ["src/impl_arm_linux_or_android.c"],
         PLATFORM_CPU_ARM64: [
+            "src/impl_aarch64_cpuid.c",
             "src/impl_aarch64_linux_or_android.c",
             "src/impl_aarch64_macos_or_iphone.c",
             "src/impl_aarch64_windows.c",
+            "src/impl_aarch64_freebsd.c",
         ],
         PLATFORM_CPU_MIPS: ["src/impl_mips_linux_or_android.c"],
         PLATFORM_CPU_PPC: ["src/impl_ppc_linux.c"],
@@ -234,7 +245,10 @@ cc_library(
             "include/internal/windows_utils.h",
         ],
         PLATFORM_CPU_ARM: ["include/cpuinfo_arm.h"],
-        PLATFORM_CPU_ARM64: ["include/cpuinfo_aarch64.h"],
+        PLATFORM_CPU_ARM64: [
+            "include/cpuinfo_aarch64.h",
+            "include/internal/cpuid_aarch64.h",
+        ],
         PLATFORM_CPU_MIPS: ["include/cpuinfo_mips.h"],
         PLATFORM_CPU_PPC: ["include/cpuinfo_ppc.h"],
         PLATFORM_CPU_RISCV32: ["include/cpuinfo_riscv.h"],
@@ -278,9 +292,11 @@ cc_library(
         ],
         PLATFORM_CPU_ARM: ["src/impl_arm_linux_or_android.c"],
         PLATFORM_CPU_ARM64: [
+            "src/impl_aarch64_cpuid.c",
             "src/impl_aarch64_linux_or_android.c",
             "src/impl_aarch64_macos_or_iphone.c",
             "src/impl_aarch64_windows.c",
+            "src/impl_aarch64_freebsd.c",
         ],
         PLATFORM_CPU_MIPS: ["src/impl_mips_linux_or_android.c"],
         PLATFORM_CPU_PPC: ["src/impl_ppc_linux.c"],
@@ -294,7 +310,10 @@ cc_library(
             "include/internal/windows_utils.h",
         ],
         PLATFORM_CPU_ARM: ["include/cpuinfo_arm.h"],
-        PLATFORM_CPU_ARM64: ["include/cpuinfo_aarch64.h"],
+        PLATFORM_CPU_ARM64: [
+            "include/cpuinfo_aarch64.h",
+            "include/internal/cpuid_aarch64.h"
+        ],
         PLATFORM_CPU_MIPS: ["include/cpuinfo_mips.h"],
         PLATFORM_CPU_PPC: ["include/cpuinfo_ppc.h"],
         PLATFORM_CPU_RISCV32: ["include/cpuinfo_riscv.h"],

CMakeLists.txt

@@ -106,6 +106,7 @@ macro(add_cpu_features_headers_and_sources HDRS_LIST_NAME SRCS_LIST_NAME)
       list(APPEND ${HDRS_LIST_NAME} ${PROJECT_SOURCE_DIR}/include/cpuinfo_arm.h)
   elseif(PROCESSOR_IS_AARCH64)
       list(APPEND ${HDRS_LIST_NAME} ${PROJECT_SOURCE_DIR}/include/cpuinfo_aarch64.h)
+      list(APPEND ${SRCS_LIST_NAME} ${PROJECT_SOURCE_DIR}/include/internal/cpuid_aarch64.h)
       list(APPEND ${SRCS_LIST_NAME} ${PROJECT_SOURCE_DIR}/include/internal/windows_utils.h)
   elseif(PROCESSOR_IS_X86)
       list(APPEND ${HDRS_LIST_NAME} ${PROJECT_SOURCE_DIR}/include/cpuinfo_x86.h)
@@ -146,6 +147,8 @@ setup_include_and_definitions(utils)
 if(UNIX)
   add_library(unix_based_hardware_detection OBJECT
     ${PROJECT_SOURCE_DIR}/include/internal/hwcaps.h
+    ${PROJECT_SOURCE_DIR}/src/hwcaps_linux_or_android.c
+    ${PROJECT_SOURCE_DIR}/src/hwcaps_freebsd.c
     ${PROJECT_SOURCE_DIR}/src/hwcaps.c
   )
   setup_include_and_definitions(unix_based_hardware_detection)
@@ -154,9 +157,13 @@ if(UNIX)
     target_compile_definitions(unix_based_hardware_detection PRIVATE HAVE_DLFCN_H)
   endif()
   check_symbol_exists(getauxval "sys/auxv.h" HAVE_STRONG_GETAUXVAL)
+  check_symbol_exists(elf_aux_info "sys/auxv.h" HAVE_STRONG_ELF_AUX_INFO)
   if(HAVE_STRONG_GETAUXVAL)
     target_compile_definitions(unix_based_hardware_detection PRIVATE HAVE_STRONG_GETAUXVAL)
   endif()
+  if(HAVE_STRONG_ELF_AUX_INFO)
+    target_compile_definitions(unix_based_hardware_detection PUBLIC HAVE_STRONG_ELF_AUX_INFO)
+  endif()
 endif()
 
 #

bazel/platforms.bzl

@@ -16,3 +16,9 @@ PLATFORM_CPU_RISCV64 = ("@platforms//cpu:riscv64")
 
 
 PLATFORM_OS_MACOS = ("@platforms//os:macos")
+
+PLATFORM_OS_LINUX = ("@platforms//os:linux")
+
+PLATFORM_OS_ANDROID = ("@platforms//os:android")
+
+PLATFORM_OS_FREEBSD = ("@platforms//os:freebsd")

include/internal/cpuid_aarch64.h

@@ -0,0 +1,28 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CPU_FEATURES_INCLUDE_CPUID_AARCH64_H_
+#define CPU_FEATURES_INCLUDE_CPUID_AARCH64_H_
+
+#include <stdint.h>
+
+#include "cpu_features_macros.h"
+
+CPU_FEATURES_START_CPP_NAMESPACE
+
+uint64_t GetMidrEl1(void);
+
+CPU_FEATURES_END_CPP_NAMESPACE
+
+#endif  // CPU_FEATURES_INCLUDE_CPUID_AARCH64_H_

src/hwcaps.c

@@ -14,12 +14,7 @@
 
 #include "internal/hwcaps.h"
 
-#include <stdlib.h>
-#include <string.h>
-
-#include "cpu_features_macros.h"
-#include "internal/filesystem.h"
-#include "internal/string_view.h"
+#include <stdbool.h>
 
 static bool IsSet(const uint32_t mask, const uint32_t value) {
   if (mask == 0) return false;
@@ -31,139 +26,3 @@ bool CpuFeatures_IsHwCapsSet(const HardwareCapabilities hwcaps_mask,
   return IsSet(hwcaps_mask.hwcaps, hwcaps.hwcaps) ||
          IsSet(hwcaps_mask.hwcaps2, hwcaps.hwcaps2);
 }
-
-#ifdef CPU_FEATURES_TEST
-// In test mode, hwcaps_for_testing will define the following functions.
-HardwareCapabilities CpuFeatures_GetHardwareCapabilities(void);
-const char* CpuFeatures_GetPlatformPointer(void);
-const char* CpuFeatures_GetBasePlatformPointer(void);
-#else
-
-// Debug facilities
-#if defined(NDEBUG)
-#define D(...)
-#else
-#include <stdio.h>
-#define D(...)           \
-  do {                   \
-    printf(__VA_ARGS__); \
-    fflush(stdout);      \
-  } while (0)
-#endif
-
-////////////////////////////////////////////////////////////////////////////////
-// Implementation of GetElfHwcapFromGetauxval
-////////////////////////////////////////////////////////////////////////////////
-
-#define AT_HWCAP 16
-#define AT_HWCAP2 26
-#define AT_PLATFORM 15
-#define AT_BASE_PLATFORM 24
-
-#if defined(HAVE_STRONG_GETAUXVAL)
-#include <sys/auxv.h>
-static unsigned long GetElfHwcapFromGetauxval(uint32_t hwcap_type) {
-  return getauxval(hwcap_type);
-}
-#elif defined(HAVE_DLFCN_H)
-// On Android we probe the system's C library for a 'getauxval' function and
-// call it if it exits, or return 0 for failure. This function is available
-// since API level 18.
-//
-// Note that getauxval() can't really be re-implemented here, because its
-// implementation does not parse /proc/self/auxv. Instead it depends on values
-// that are passed by the kernel at process-init time to the C runtime
-// initialization layer.
-
-#include <dlfcn.h>
-
-typedef unsigned long getauxval_func_t(unsigned long);
-
-static uint32_t GetElfHwcapFromGetauxval(uint32_t hwcap_type) {
-  uint32_t ret = 0;
-  void *libc_handle = NULL;
-  getauxval_func_t *func = NULL;
-
-  dlerror();  // Cleaning error state before calling dlopen.
-  libc_handle = dlopen("libc.so", RTLD_NOW);
-  if (!libc_handle) {
-    D("Could not dlopen() C library: %s\n", dlerror());
-    return 0;
-  }
-  func = (getauxval_func_t *)dlsym(libc_handle, "getauxval");
-  if (!func) {
-    D("Could not find getauxval() in C library\n");
-  } else {
-    // Note: getauxval() returns 0 on failure. Doesn't touch errno.
-    ret = (uint32_t)(*func)(hwcap_type);
-  }
-  dlclose(libc_handle);
-  return ret;
-}
-#else
-#error "This platform does not provide hardware capabilities."
-#endif
-
-// Implementation of GetHardwareCapabilities for OS that provide
-// GetElfHwcapFromGetauxval().
-
-// Fallback when getauxval is not available, retrieves hwcaps from
-// "/proc/self/auxv".
-static uint32_t GetElfHwcapFromProcSelfAuxv(uint32_t hwcap_type) {
-  struct {
-    uint32_t tag;
-    uint32_t value;
-  } entry;
-  uint32_t result = 0;
-  const char filepath[] = "/proc/self/auxv";
-  const int fd = CpuFeatures_OpenFile(filepath);
-  if (fd < 0) {
-    D("Could not open %s\n", filepath);
-    return 0;
-  }
-  for (;;) {
-    const int ret = CpuFeatures_ReadFile(fd, (char *)&entry, sizeof entry);
-    if (ret < 0) {
-      D("Error while reading %s\n", filepath);
-      break;
-    }
-    // Detect end of list.
-    if (ret == 0 || (entry.tag == 0 && entry.value == 0)) {
-      break;
-    }
-    if (entry.tag == hwcap_type) {
-      result = entry.value;
-      break;
-    }
-  }
-  CpuFeatures_CloseFile(fd);
-  return result;
-}
-
-// Retrieves hardware capabilities by first trying to call getauxval, if not
-// available falls back to reading "/proc/self/auxv".
-static unsigned long GetHardwareCapabilitiesFor(uint32_t type) {
-  unsigned long hwcaps = GetElfHwcapFromGetauxval(type);
-  if (!hwcaps) {
-    D("Parsing /proc/self/auxv to extract ELF hwcaps!\n");
-    hwcaps = GetElfHwcapFromProcSelfAuxv(type);
-  }
-  return hwcaps;
-}
-
-HardwareCapabilities CpuFeatures_GetHardwareCapabilities(void) {
-  HardwareCapabilities capabilities;
-  capabilities.hwcaps = GetHardwareCapabilitiesFor(AT_HWCAP);
-  capabilities.hwcaps2 = GetHardwareCapabilitiesFor(AT_HWCAP2);
-  return capabilities;
-}
-
-const char *CpuFeatures_GetPlatformPointer(void) {
-  return (const char *)GetHardwareCapabilitiesFor(AT_PLATFORM);
-}
-
-const char *CpuFeatures_GetBasePlatformPointer(void) {
-  return (const char *)GetHardwareCapabilitiesFor(AT_BASE_PLATFORM);
-}
-
-#endif  // CPU_FEATURES_TEST

src/hwcaps_freebsd.c

@@ -0,0 +1,54 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "cpu_features_macros.h"
+
+#ifdef CPU_FEATURES_OS_FREEBSD
+
+#include "internal/hwcaps.h"
+
+#ifdef CPU_FEATURES_TEST
+// In test mode, hwcaps_for_testing will define the following functions.
+HardwareCapabilities CpuFeatures_GetHardwareCapabilities(void);
+const char* CpuFeatures_GetPlatformPointer(void);
+const char* CpuFeatures_GetBasePlatformPointer(void);
+#else
+
+#ifdef HAVE_STRONG_ELF_AUX_INFO
+#include <stddef.h>
+#include <sys/auxv.h>
+
+static unsigned long GetElfHwcapFromElfAuxInfo(int hwcap_type) {
+  unsigned long hwcap;
+  elf_aux_info(hwcap_type, &hwcap, sizeof(hwcap));
+  return hwcap;
+}
+
+HardwareCapabilities CpuFeatures_GetHardwareCapabilities(void) {
+  HardwareCapabilities capabilities;
+  capabilities.hwcaps = GetElfHwcapFromElfAuxInfo(AT_HWCAP);
+  capabilities.hwcaps2 = GetElfHwcapFromElfAuxInfo(AT_HWCAP2);
+  return capabilities;
+}
+
+const char *CpuFeatures_GetPlatformPointer(void) { return NULL; }
+
+const char *CpuFeatures_GetBasePlatformPointer(void) { return NULL; }
+
+#else
+#error "FreeBSD needs support for elf_aux_info"
+#endif  // HAVE_STRONG_ELF_AUX_INFO
+
+#endif  // CPU_FEATURES_TEST
+#endif  // CPU_FEATURES_OS_FREEBSD