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			260 lines
		
	
	
		
			8.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			260 lines
		
	
	
		
			8.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // Copyright 2017 Google Inc.
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| //
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| // Licensed under the Apache License, Version 2.0 (the "License");
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| // you may not use this file except in compliance with the License.
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| // You may obtain a copy of the License at
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| //
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| //    http://www.apache.org/licenses/LICENSE-2.0
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| //
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| // Unless required by applicable law or agreed to in writing, software
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| // distributed under the License is distributed on an "AS IS" BASIS,
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| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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| // See the License for the specific language governing permissions and
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| // limitations under the License.
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| 
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| #include "cpuinfo_arm.h"
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| 
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| #include "internal/bit_utils.h"
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| #include "internal/filesystem.h"
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| #include "internal/hwcaps.h"
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| #include "internal/linux_features_aggregator.h"
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| #include "internal/stack_line_reader.h"
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| #include "internal/string_view.h"
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| 
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| #include <ctype.h>
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| 
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| DECLARE_SETTER(ArmFeatures, vfp)
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| DECLARE_SETTER(ArmFeatures, iwmmxt)
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| DECLARE_SETTER(ArmFeatures, neon)
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| DECLARE_SETTER(ArmFeatures, vfpv3)
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| DECLARE_SETTER(ArmFeatures, vfpv3d16)
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| DECLARE_SETTER(ArmFeatures, vfpv4)
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| DECLARE_SETTER(ArmFeatures, idiva)
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| DECLARE_SETTER(ArmFeatures, idivt)
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| DECLARE_SETTER(ArmFeatures, aes)
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| DECLARE_SETTER(ArmFeatures, pmull)
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| DECLARE_SETTER(ArmFeatures, sha1)
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| DECLARE_SETTER(ArmFeatures, sha2)
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| DECLARE_SETTER(ArmFeatures, crc32)
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| 
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| static const CapabilityConfig kConfigs[] = {
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|     {{ARM_HWCAP_VFP, 0}, "vfp", &set_vfp},                 //
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|     {{ARM_HWCAP_IWMMXT, 0}, "iwmmxt", &set_iwmmxt},        //
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|     {{ARM_HWCAP_NEON, 0}, "neon", &set_neon},              //
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|     {{ARM_HWCAP_VFPV3, 0}, "vfpv3", &set_vfpv3},           //
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|     {{ARM_HWCAP_VFPV3D16, 0}, "vfpv3d16", &set_vfpv3d16},  //
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|     {{ARM_HWCAP_VFPV4, 0}, "vfpv4", &set_vfpv4},           //
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|     {{ARM_HWCAP_IDIVA, 0}, "idiva", &set_idiva},           //
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|     {{ARM_HWCAP_IDIVT, 0}, "idivt", &set_idivt},           //
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|     {{0, ARM_HWCAP2_AES}, "aes", &set_aes},                //
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|     {{0, ARM_HWCAP2_PMULL}, "pmull", &set_pmull},          //
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|     {{0, ARM_HWCAP2_SHA1}, "sha1", &set_sha1},             //
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|     {{0, ARM_HWCAP2_SHA2}, "sha2", &set_sha2},             //
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|     {{0, ARM_HWCAP2_CRC32}, "crc32", &set_crc32},          //
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| };
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| 
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| static const size_t kConfigsSize = sizeof(kConfigs) / sizeof(CapabilityConfig);
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| 
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| typedef struct {
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|   bool processor_reports_armv6;
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|   bool hardware_reports_goldfish;
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| } ProcCpuInfoData;
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| 
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| static int IndexOfNonDigit(StringView str) {
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|   size_t index = 0;
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|   while (str.size && isdigit(CpuFeatures_StringView_Front(str))) {
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|     str = CpuFeatures_StringView_PopFront(str, 1);
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|     ++index;
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|   }
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|   return index;
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| }
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| 
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| static bool HandleArmLine(const LineResult result, ArmInfo* const info,
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|                           ProcCpuInfoData* const proc_info) {
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|   StringView line = result.line;
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|   StringView key, value;
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|   if (CpuFeatures_StringView_GetAttributeKeyValue(line, &key, &value)) {
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|     if (CpuFeatures_StringView_IsEquals(key, str("Features"))) {
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|       CpuFeatures_SetFromFlags(kConfigsSize, kConfigs, value, &info->features);
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|     } else if (CpuFeatures_StringView_IsEquals(key, str("CPU implementer"))) {
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|       info->implementer = CpuFeatures_StringView_ParsePositiveNumber(value);
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|     } else if (CpuFeatures_StringView_IsEquals(key, str("CPU variant"))) {
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|       info->variant = CpuFeatures_StringView_ParsePositiveNumber(value);
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|     } else if (CpuFeatures_StringView_IsEquals(key, str("CPU part"))) {
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|       info->part = CpuFeatures_StringView_ParsePositiveNumber(value);
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|     } else if (CpuFeatures_StringView_IsEquals(key, str("CPU revision"))) {
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|       info->revision = CpuFeatures_StringView_ParsePositiveNumber(value);
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|     } else if (CpuFeatures_StringView_IsEquals(key, str("CPU architecture"))) {
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|       // CPU architecture is a number that may be followed by letters. e.g.
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|       // "6TEJ", "7".
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|       const StringView digits =
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|           CpuFeatures_StringView_KeepFront(value, IndexOfNonDigit(value));
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|       info->architecture = CpuFeatures_StringView_ParsePositiveNumber(digits);
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|     } else if (CpuFeatures_StringView_IsEquals(key, str("Processor"))) {
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|       proc_info->processor_reports_armv6 =
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|           CpuFeatures_StringView_IndexOf(value, str("(v6l)")) >= 0;
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|     } else if (CpuFeatures_StringView_IsEquals(key, str("Hardware"))) {
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|       proc_info->hardware_reports_goldfish =
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|           CpuFeatures_StringView_IsEquals(value, str("Goldfish"));
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|     }
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|   }
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|   return !result.eof;
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| }
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| 
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| static uint32_t GetCpuId(const ArmInfo* const info) {
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|   return (ExtractBitRange(info->implementer, 7, 0) << 24) |
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|          (ExtractBitRange(info->variant, 3, 0) << 20) |
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|          (ExtractBitRange(info->part, 11, 0) << 4) |
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|          (ExtractBitRange(info->revision, 3, 0) << 0);
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| }
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| 
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| static void FixErrors(ArmInfo* const info,
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|                       ProcCpuInfoData* const proc_cpu_info_data) {
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|   // Fixing Samsung kernel reporting invalid cpu architecture.
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|   // http://code.google.com/p/android/issues/detail?id=10812
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|   if (proc_cpu_info_data->processor_reports_armv6 && info->architecture >= 7) {
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|     info->architecture = 6;
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|   }
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| 
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|   // Handle kernel configuration bugs that prevent the correct reporting of CPU
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|   // features.
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|   switch (GetCpuId(info)) {
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|     case 0x4100C080:
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|       // Special case: The emulator-specific Android 4.2 kernel fails to report
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|       // support for the 32-bit ARM IDIV instruction. Technically, this is a
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|       // feature of the virtual CPU implemented by the emulator. Note that it
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|       // could also support Thumb IDIV in the future, and this will have to be
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|       // slightly updated.
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|       if (info->architecture >= 7 &&
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|           proc_cpu_info_data->hardware_reports_goldfish) {
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|         info->features.idiva = true;
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|       }
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|       break;
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|     case 0x511004D0:
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|       // https://crbug.com/341598.
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|       info->features.neon = false;
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|       break;
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|     case 0x510006F2:
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|     case 0x510006F3:
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|       // The Nexus 4 (Qualcomm Krait) kernel configuration forgets to report
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|       // IDIV support.
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|       info->features.idiva = true;
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|       info->features.idivt = true;
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|       break;
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|   }
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| 
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|   // Propagate cpu features.
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|   if (info->features.vfpv4) info->features.vfpv3 = true;
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|   if (info->features.neon) info->features.vfpv3 = true;
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|   if (info->features.vfpv3) info->features.vfp = true;
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| }
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| 
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| static void FillProcCpuInfoData(ArmInfo* const info,
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|                                 ProcCpuInfoData* proc_cpu_info_data) {
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|   const int fd = CpuFeatures_OpenFile("/proc/cpuinfo");
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|   if (fd >= 0) {
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|     StackLineReader reader;
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|     StackLineReader_Initialize(&reader, fd);
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|     for (;;) {
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|       if (!HandleArmLine(StackLineReader_NextLine(&reader), info,
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|                          proc_cpu_info_data)) {
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|         break;
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|       }
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|     }
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|     CpuFeatures_CloseFile(fd);
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|   }
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| }
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| 
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| static const ArmInfo kEmptyArmInfo;
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| 
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| static const ProcCpuInfoData kEmptyProcCpuInfoData;
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| 
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| ArmInfo GetArmInfo(void) {
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|   // capabilities are fetched from both getauxval and /proc/cpuinfo so we can
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|   // have some information if the executable is sandboxed (aka no access to
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|   // /proc/cpuinfo).
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|   ArmInfo info = kEmptyArmInfo;
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|   ProcCpuInfoData proc_cpu_info_data = kEmptyProcCpuInfoData;
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| 
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|   FillProcCpuInfoData(&info, &proc_cpu_info_data);
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|   CpuFeatures_OverrideFromHwCaps(kConfigsSize, kConfigs,
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|                                  CpuFeatures_GetHardwareCapabilities(),
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|                                  &info.features);
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| 
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|   FixErrors(&info, &proc_cpu_info_data);
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| 
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|   return info;
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| }
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| 
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| ////////////////////////////////////////////////////////////////////////////////
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| // Introspection functions
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| 
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| int GetArmFeaturesEnumValue(const ArmFeatures* features,
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|                             ArmFeaturesEnum value) {
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|   switch (value) {
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|     case ARM_VFP:
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|       return features->vfp;
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|     case ARM_IWMMXT:
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|       return features->iwmmxt;
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|     case ARM_NEON:
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|       return features->neon;
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|     case ARM_VFPV3:
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|       return features->vfpv3;
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|     case ARM_VFPV3D16:
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|       return features->vfpv3d16;
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|     case ARM_VFPV4:
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|       return features->vfpv4;
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|     case ARM_IDIVA:
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|       return features->idiva;
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|     case ARM_IDIVT:
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|       return features->idivt;
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|     case ARM_AES:
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|       return features->aes;
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|     case ARM_PMULL:
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|       return features->pmull;
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|     case ARM_SHA1:
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|       return features->sha1;
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|     case ARM_SHA2:
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|       return features->sha2;
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|     case ARM_CRC32:
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|       return features->crc32;
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|     case ARM_LAST_:
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|       break;
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|   }
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|   return false;
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| }
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| 
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| const char* GetArmFeaturesEnumName(ArmFeaturesEnum value) {
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|   switch (value) {
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|     case ARM_VFP:
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|       return "vfp";
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|     case ARM_IWMMXT:
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|       return "iwmmxt";
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|     case ARM_NEON:
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|       return "neon";
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|     case ARM_VFPV3:
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|       return "vfpv3";
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|     case ARM_VFPV3D16:
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|       return "vfpv3d16";
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|     case ARM_VFPV4:
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|       return "vfpv4";
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|     case ARM_IDIVA:
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|       return "idiva";
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|     case ARM_IDIVT:
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|       return "idivt";
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|     case ARM_AES:
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|       return "aes";
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|     case ARM_PMULL:
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|       return "pmull";
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|     case ARM_SHA1:
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|       return "sha1";
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|     case ARM_SHA2:
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|       return "sha2";
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|     case ARM_CRC32:
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|       return "crc32";
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|     case ARM_LAST_:
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|       break;
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|   }
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|   return "unknown feature";
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| }
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