Move platform abstraction to base library

src/cpu.cc

Index: src/cpu.cc
diff --git a/src/cpu.cc b/src/cpu.cc
deleted file mode 100644
index 6b04e20ed85c28d982771fc7125831f6ca61a3b6..0000000000000000000000000000000000000000
--- a/src/cpu.cc
+++ /dev/null
@@ -1,498 +0,0 @@
-// Copyright 2013 the V8 project authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "src/cpu.h"
-
-#if V8_LIBC_MSVCRT
-#include <intrin.h>  // __cpuid()
-#endif
-#if V8_OS_POSIX
-#include <unistd.h>  // sysconf()
-#endif
-#if V8_OS_QNX
-#include <sys/syspage.h>  // cpuinfo
-#endif
-
-#include <ctype.h>
-#include <limits.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <algorithm>
-
-#include "src/checks.h"
-#if V8_OS_WIN
-#include "src/base/win32-headers.h"  // NOLINT
-#endif
-
-namespace v8 {
-namespace internal {
-
-#if V8_HOST_ARCH_IA32 || V8_HOST_ARCH_X64
-
-// Define __cpuid() for non-MSVC libraries.
-#if !V8_LIBC_MSVCRT
-
-static V8_INLINE void __cpuid(int cpu_info[4], int info_type) {
-#if defined(__i386__) && defined(__pic__)
-  // Make sure to preserve ebx, which contains the pointer
-  // to the GOT in case we're generating PIC.
-  __asm__ volatile (
-    "mov %%ebx, %%edi\n\t"
-    "cpuid\n\t"
-    "xchg %%edi, %%ebx\n\t"
-    : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
-    : "a"(info_type)
-  );
-#else
-  __asm__ volatile (
-    "cpuid \n\t"
-    : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
-    : "a"(info_type)
-  );
-#endif  // defined(__i386__) && defined(__pic__)
-}
-
-#endif  // !V8_LIBC_MSVCRT
-
-#elif V8_HOST_ARCH_ARM || V8_HOST_ARCH_ARM64 || V8_HOST_ARCH_MIPS
-
-#if V8_OS_LINUX
-
-#if V8_HOST_ARCH_ARM
-
-// See <uapi/asm/hwcap.h> kernel header.
-/*
- * HWCAP flags - for elf_hwcap (in kernel) and AT_HWCAP
- */
-#define HWCAP_SWP (1 << 0)
-#define HWCAP_HALF  (1 << 1)
-#define HWCAP_THUMB (1 << 2)
-#define HWCAP_26BIT (1 << 3)  /* Play it safe */
-#define HWCAP_FAST_MULT (1 << 4)
-#define HWCAP_FPA (1 << 5)
-#define HWCAP_VFP (1 << 6)
-#define HWCAP_EDSP  (1 << 7)
-#define HWCAP_JAVA  (1 << 8)
-#define HWCAP_IWMMXT  (1 << 9)
-#define HWCAP_CRUNCH  (1 << 10)
-#define HWCAP_THUMBEE (1 << 11)
-#define HWCAP_NEON  (1 << 12)
-#define HWCAP_VFPv3 (1 << 13)
-#define HWCAP_VFPv3D16  (1 << 14) /* also set for VFPv4-D16 */
-#define HWCAP_TLS (1 << 15)
-#define HWCAP_VFPv4 (1 << 16)
-#define HWCAP_IDIVA (1 << 17)
-#define HWCAP_IDIVT (1 << 18)
-#define HWCAP_VFPD32  (1 << 19) /* set if VFP has 32 regs (not 16) */
-#define HWCAP_IDIV  (HWCAP_IDIVA | HWCAP_IDIVT)
-#define HWCAP_LPAE  (1 << 20)
-
-#define AT_HWCAP 16
-
-// Read the ELF HWCAP flags by parsing /proc/self/auxv.
-static uint32_t ReadELFHWCaps() {
-  uint32_t result = 0;
-  FILE* fp = fopen("/proc/self/auxv", "r");
-  if (fp != NULL) {
-    struct { uint32_t tag; uint32_t value; } entry;
-    for (;;) {
-      size_t n = fread(&entry, sizeof(entry), 1, fp);
-      if (n == 0 || (entry.tag == 0 && entry.value == 0)) {
-        break;
-      }
-      if (entry.tag == AT_HWCAP) {
-        result = entry.value;
-        break;
-      }
-    }
-    fclose(fp);
-  }
-  return result;
-}
-
-#endif  // V8_HOST_ARCH_ARM
-
-// Extract the information exposed by the kernel via /proc/cpuinfo.
-class CPUInfo V8_FINAL BASE_EMBEDDED {
- public:
-  CPUInfo() : datalen_(0) {
-    // Get the size of the cpuinfo file by reading it until the end. This is
-    // required because files under /proc do not always return a valid size
-    // when using fseek(0, SEEK_END) + ftell(). Nor can the be mmap()-ed.
-    static const char PATHNAME[] = "/proc/cpuinfo";
-    FILE* fp = fopen(PATHNAME, "r");
-    if (fp != NULL) {
-      for (;;) {
-        char buffer[256];
-        size_t n = fread(buffer, 1, sizeof(buffer), fp);
-        if (n == 0) {
-          break;
-        }
-        datalen_ += n;
-      }
-      fclose(fp);
-    }
-
-    // Read the contents of the cpuinfo file.
-    data_ = new char[datalen_ + 1];
-    fp = fopen(PATHNAME, "r");
-    if (fp != NULL) {
-      for (size_t offset = 0; offset < datalen_; ) {
-        size_t n = fread(data_ + offset, 1, datalen_ - offset, fp);
-        if (n == 0) {
-          break;
-        }
-        offset += n;
-      }
-      fclose(fp);
-    }
-
-    // Zero-terminate the data.
-    data_[datalen_] = '\0';
-  }
-
-  ~CPUInfo() {
-    delete[] data_;
-  }
-
-  // Extract the content of a the first occurence of a given field in
-  // the content of the cpuinfo file and return it as a heap-allocated
-  // string that must be freed by the caller using delete[].
-  // Return NULL if not found.
-  char* ExtractField(const char* field) const {
-    ASSERT(field != NULL);
-
-    // Look for first field occurence, and ensure it starts the line.
-    size_t fieldlen = strlen(field);
-    char* p = data_;
-    for (;;) {
-      p = strstr(p, field);
-      if (p == NULL) {
-        return NULL;
-      }
-      if (p == data_ || p[-1] == '\n') {
-        break;
-      }
-      p += fieldlen;
-    }
-
-    // Skip to the first colon followed by a space.
-    p = strchr(p + fieldlen, ':');
-    if (p == NULL || !isspace(p[1])) {
-      return NULL;
-    }
-    p += 2;
-
-    // Find the end of the line.
-    char* q = strchr(p, '\n');
-    if (q == NULL) {
-      q = data_ + datalen_;
-    }
-
-    // Copy the line into a heap-allocated buffer.
-    size_t len = q - p;
-    char* result = new char[len + 1];
-    if (result != NULL) {
-      memcpy(result, p, len);
-      result[len] = '\0';
-    }
-    return result;
-  }
-
- private:
-  char* data_;
-  size_t datalen_;
-};
-
-#if V8_HOST_ARCH_ARM || V8_HOST_ARCH_MIPS
-
-// Checks that a space-separated list of items contains one given 'item'.
-static bool HasListItem(const char* list, const char* item) {
-  ssize_t item_len = strlen(item);
-  const char* p = list;
-  if (p != NULL) {
-    while (*p != '\0') {
-      // Skip whitespace.
-      while (isspace(*p)) ++p;
-
-      // Find end of current list item.
-      const char* q = p;
-      while (*q != '\0' && !isspace(*q)) ++q;
-
-      if (item_len == q - p && memcmp(p, item, item_len) == 0) {
-        return true;
-      }
-
-      // Skip to next item.
-      p = q;
-    }
-  }
-  return false;
-}
-
-#endif  // V8_HOST_ARCH_ARM || V8_HOST_ARCH_MIPS
-
-#endif  // V8_OS_LINUX
-
-#endif  // V8_HOST_ARCH_IA32 || V8_HOST_ARCH_X64
-
-CPU::CPU() : stepping_(0),
-             model_(0),
-             ext_model_(0),
-             family_(0),
-             ext_family_(0),
-             type_(0),
-             implementer_(0),
-             architecture_(0),
-             part_(0),
-             has_fpu_(false),
-             has_cmov_(false),
-             has_sahf_(false),
-             has_mmx_(false),
-             has_sse_(false),
-             has_sse2_(false),
-             has_sse3_(false),
-             has_ssse3_(false),
-             has_sse41_(false),
-             has_sse42_(false),
-             has_idiva_(false),
-             has_neon_(false),
-             has_thumb2_(false),
-             has_vfp_(false),
-             has_vfp3_(false),
-             has_vfp3_d32_(false) {
-  memcpy(vendor_, "Unknown", 8);
-#if V8_HOST_ARCH_IA32 || V8_HOST_ARCH_X64
-  int cpu_info[4];
-
-  // __cpuid with an InfoType argument of 0 returns the number of
-  // valid Ids in CPUInfo[0] and the CPU identification string in
-  // the other three array elements. The CPU identification string is
-  // not in linear order. The code below arranges the information
-  // in a human readable form. The human readable order is CPUInfo[1] |
-  // CPUInfo[3] | CPUInfo[2]. CPUInfo[2] and CPUInfo[3] are swapped
-  // before using memcpy to copy these three array elements to cpu_string.
-  __cpuid(cpu_info, 0);
-  unsigned num_ids = cpu_info[0];
-  std::swap(cpu_info[2], cpu_info[3]);
-  memcpy(vendor_, cpu_info + 1, 12);
-  vendor_[12] = '\0';
-
-  // Interpret CPU feature information.
-  if (num_ids > 0) {
-    __cpuid(cpu_info, 1);
-    stepping_ = cpu_info[0] & 0xf;
-    model_ = ((cpu_info[0] >> 4) & 0xf) + ((cpu_info[0] >> 12) & 0xf0);
-    family_ = (cpu_info[0] >> 8) & 0xf;
-    type_ = (cpu_info[0] >> 12) & 0x3;
-    ext_model_ = (cpu_info[0] >> 16) & 0xf;
-    ext_family_ = (cpu_info[0] >> 20) & 0xff;
-    has_fpu_ = (cpu_info[3] & 0x00000001) != 0;
-    has_cmov_ = (cpu_info[3] & 0x00008000) != 0;
-    has_mmx_ = (cpu_info[3] & 0x00800000) != 0;
-    has_sse_ = (cpu_info[3] & 0x02000000) != 0;
-    has_sse2_ = (cpu_info[3] & 0x04000000) != 0;
-    has_sse3_ = (cpu_info[2] & 0x00000001) != 0;
-    has_ssse3_ = (cpu_info[2] & 0x00000200) != 0;
-    has_sse41_ = (cpu_info[2] & 0x00080000) != 0;
-    has_sse42_ = (cpu_info[2] & 0x00100000) != 0;
-  }
-
-#if V8_HOST_ARCH_IA32
-  // SAHF is always available in compat/legacy mode,
-  has_sahf_ = true;
-#else
-  // Query extended IDs.
-  __cpuid(cpu_info, 0x80000000);
-  unsigned num_ext_ids = cpu_info[0];
-
-  // Interpret extended CPU feature information.
-  if (num_ext_ids > 0x80000000) {
-    __cpuid(cpu_info, 0x80000001);
-    // SAHF must be probed in long mode.
-    has_sahf_ = (cpu_info[2] & 0x00000001) != 0;
-  }
-#endif
-
-#elif V8_HOST_ARCH_ARM
-
-#if V8_OS_LINUX
-
-  CPUInfo cpu_info;
-
-  // Extract implementor from the "CPU implementer" field.
-  char* implementer = cpu_info.ExtractField("CPU implementer");
-  if (implementer != NULL) {
-    char* end ;
-    implementer_ = strtol(implementer, &end, 0);
-    if (end == implementer) {
-      implementer_ = 0;
-    }
-    delete[] implementer;
-  }
-
-  // Extract part number from the "CPU part" field.
-  char* part = cpu_info.ExtractField("CPU part");
-  if (part != NULL) {
-    char* end ;
-    part_ = strtol(part, &end, 0);
-    if (end == part) {
-      part_ = 0;
-    }
-    delete[] part;
-  }
-
-  // Extract architecture from the "CPU Architecture" field.
-  // The list is well-known, unlike the the output of
-  // the 'Processor' field which can vary greatly.
-  // See the definition of the 'proc_arch' array in
-  // $KERNEL/arch/arm/kernel/setup.c and the 'c_show' function in
-  // same file.
-  char* architecture = cpu_info.ExtractField("CPU architecture");
-  if (architecture != NULL) {
-    char* end;
-    architecture_ = strtol(architecture, &end, 10);
-    if (end == architecture) {
-      architecture_ = 0;
-    }
-    delete[] architecture;
-
-    // Unfortunately, it seems that certain ARMv6-based CPUs
-    // report an incorrect architecture number of 7!
-    //
-    // See http://code.google.com/p/android/issues/detail?id=10812
-    //
-    // We try to correct this by looking at the 'elf_format'
-    // field reported by the 'Processor' field, which is of the
-    // form of "(v7l)" for an ARMv7-based CPU, and "(v6l)" for
-    // an ARMv6-one. For example, the Raspberry Pi is one popular
-    // ARMv6 device that reports architecture 7.
-    if (architecture_ == 7) {
-      char* processor = cpu_info.ExtractField("Processor");
-      if (HasListItem(processor, "(v6l)")) {
-        architecture_ = 6;
-      }
-      delete[] processor;
-    }
-  }
-
-  // Try to extract the list of CPU features from ELF hwcaps.
-  uint32_t hwcaps = ReadELFHWCaps();
-  if (hwcaps != 0) {
-    has_idiva_ = (hwcaps & HWCAP_IDIVA) != 0;
-    has_neon_ = (hwcaps & HWCAP_NEON) != 0;
-    has_vfp_ = (hwcaps & HWCAP_VFP) != 0;
-    has_vfp3_ = (hwcaps & (HWCAP_VFPv3 | HWCAP_VFPv3D16 | HWCAP_VFPv4)) != 0;
-    has_vfp3_d32_ = (has_vfp3_ && ((hwcaps & HWCAP_VFPv3D16) == 0 ||
-                                   (hwcaps & HWCAP_VFPD32) != 0));
-  } else {
-    // Try to fallback to "Features" CPUInfo field.
-    char* features = cpu_info.ExtractField("Features");
-    has_idiva_ = HasListItem(features, "idiva");
-    has_neon_ = HasListItem(features, "neon");
-    has_thumb2_ = HasListItem(features, "thumb2");
-    has_vfp_ = HasListItem(features, "vfp");
-    if (HasListItem(features, "vfpv3d16")) {
-      has_vfp3_ = true;
-    } else if (HasListItem(features, "vfpv3")) {
-      has_vfp3_ = true;
-      has_vfp3_d32_ = true;
-    }
-    delete[] features;
-  }
-
-  // Some old kernels will report vfp not vfpv3. Here we make an attempt
-  // to detect vfpv3 by checking for vfp *and* neon, since neon is only
-  // available on architectures with vfpv3. Checking neon on its own is
-  // not enough as it is possible to have neon without vfp.
-  if (has_vfp_ && has_neon_) {
-    has_vfp3_ = true;
-  }
-
-  // VFPv3 implies ARMv7, see ARM DDI 0406B, page A1-6.
-  if (architecture_ < 7 && has_vfp3_) {
-    architecture_ = 7;
-  }
-
-  // ARMv7 implies Thumb2.
-  if (architecture_ >= 7) {
-    has_thumb2_ = true;
-  }
-
-  // The earliest architecture with Thumb2 is ARMv6T2.
-  if (has_thumb2_ && architecture_ < 6) {
-    architecture_ = 6;
-  }
-
-  // We don't support any FPUs other than VFP.
-  has_fpu_ = has_vfp_;
-
-#elif V8_OS_QNX
-
-  uint32_t cpu_flags = SYSPAGE_ENTRY(cpuinfo)->flags;
-  if (cpu_flags & ARM_CPU_FLAG_V7) {
-    architecture_ = 7;
-    has_thumb2_ = true;
-  } else if (cpu_flags & ARM_CPU_FLAG_V6) {
-    architecture_ = 6;
-    // QNX doesn't say if Thumb2 is available.
-    // Assume false for the architectures older than ARMv7.
-  }
-  ASSERT(architecture_ >= 6);
-  has_fpu_ = (cpu_flags & CPU_FLAG_FPU) != 0;
-  has_vfp_ = has_fpu_;
-  if (cpu_flags & ARM_CPU_FLAG_NEON) {
-    has_neon_ = true;
-    has_vfp3_ = has_vfp_;
-#ifdef ARM_CPU_FLAG_VFP_D32
-    has_vfp3_d32_ = (cpu_flags & ARM_CPU_FLAG_VFP_D32) != 0;
-#endif
-  }
-  has_idiva_ = (cpu_flags & ARM_CPU_FLAG_IDIV) != 0;
-
-#endif  // V8_OS_LINUX
-
-#elif V8_HOST_ARCH_MIPS
-
-  // Simple detection of FPU at runtime for Linux.
-  // It is based on /proc/cpuinfo, which reveals hardware configuration
-  // to user-space applications.  According to MIPS (early 2010), no similar
-  // facility is universally available on the MIPS architectures,
-  // so it's up to individual OSes to provide such.
-  CPUInfo cpu_info;
-  char* cpu_model = cpu_info.ExtractField("cpu model");
-  has_fpu_ = HasListItem(cpu_model, "FPU");
-  delete[] cpu_model;
-
-#elif V8_HOST_ARCH_ARM64
-
-  CPUInfo cpu_info;
-
-  // Extract implementor from the "CPU implementer" field.
-  char* implementer = cpu_info.ExtractField("CPU implementer");
-  if (implementer != NULL) {
-    char* end ;
-    implementer_ = strtol(implementer, &end, 0);
-    if (end == implementer) {
-      implementer_ = 0;
-    }
-    delete[] implementer;
-  }
-
-  // Extract part number from the "CPU part" field.
-  char* part = cpu_info.ExtractField("CPU part");
-  if (part != NULL) {
-    char* end ;
-    part_ = strtol(part, &end, 0);
-    if (end == part) {
-      part_ = 0;
-    }
-    delete[] part;
-  }
-
-#endif
-}
-
-} }  // namespace v8::internal