//===-- Host.cpp - Implement OS Host Concept --------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//  This header file implements the operating system Host concept.
//
//===----------------------------------------------------------------------===//

#include "llvm/System/Host.h"
#include "llvm/Config/config.h"
#include <string.h>

// Include the platform-specific parts of this class.
#ifdef LLVM_ON_UNIX
#include "Unix/Host.inc"
#endif
#ifdef LLVM_ON_WIN32
#include "Win32/Host.inc"
#endif

//===----------------------------------------------------------------------===//
//
//  Implementations of the CPU detection routines
//
//===----------------------------------------------------------------------===//

using namespace llvm;

#if defined(i386) || defined(__i386__) || defined(__x86__) || defined(_M_IX86)\
 || defined(__x86_64__) || defined(_M_AMD64) || defined (_M_X64)

/// GetX86CpuIDAndInfo - Execute the specified cpuid and return the 4 values in the
/// specified arguments.  If we can't run cpuid on the host, return true.
static bool GetX86CpuIDAndInfo(unsigned value, unsigned *rEAX,
                            unsigned *rEBX, unsigned *rECX, unsigned *rEDX) {
#if defined(__x86_64__) || defined(_M_AMD64) || defined (_M_X64)
  #if defined(__GNUC__)
    // gcc doesn't know cpuid would clobber ebx/rbx. Preseve it manually.
    asm ("movq\t%%rbx, %%rsi\n\t"
         "cpuid\n\t"
         "xchgq\t%%rbx, %%rsi\n\t"
         : "=a" (*rEAX),
           "=S" (*rEBX),
           "=c" (*rECX),
           "=d" (*rEDX)
         :  "a" (value));
    return false;
  #elif defined(_MSC_VER)
    int registers[4];
    __cpuid(registers, value);
    *rEAX = registers[0];
    *rEBX = registers[1];
    *rECX = registers[2];
    *rEDX = registers[3];
    return false;
  #endif
#elif defined(i386) || defined(__i386__) || defined(__x86__) || defined(_M_IX86)
  #if defined(__GNUC__)
    asm ("movl\t%%ebx, %%esi\n\t"
         "cpuid\n\t"
         "xchgl\t%%ebx, %%esi\n\t"
         : "=a" (*rEAX),
           "=S" (*rEBX),
           "=c" (*rECX),
           "=d" (*rEDX)
         :  "a" (value));
    return false;
  #elif defined(_MSC_VER)
    __asm {
      mov   eax,value
      cpuid
      mov   esi,rEAX
      mov   dword ptr [esi],eax
      mov   esi,rEBX
      mov   dword ptr [esi],ebx
      mov   esi,rECX
      mov   dword ptr [esi],ecx
      mov   esi,rEDX
      mov   dword ptr [esi],edx
    }
    return false;
  #endif
#endif
  return true;
}

static void DetectX86FamilyModel(unsigned EAX, unsigned &Family, unsigned &Model) {
  Family = (EAX >> 8) & 0xf; // Bits 8 - 11
  Model  = (EAX >> 4) & 0xf; // Bits 4 - 7
  if (Family == 6 || Family == 0xf) {
    if (Family == 0xf)
      // Examine extended family ID if family ID is F.
      Family += (EAX >> 20) & 0xff;    // Bits 20 - 27
    // Examine extended model ID if family ID is 6 or F.
    Model += ((EAX >> 16) & 0xf) << 4; // Bits 16 - 19
  }
}
#endif


std::string sys::getHostCPUName() {
#if defined(__x86_64__) || defined(__i386__)
  unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
  if (GetX86CpuIDAndInfo(0x1, &EAX, &EBX, &ECX, &EDX))
    return "generic";
  unsigned Family = 0;
  unsigned Model  = 0;
  DetectX86FamilyModel(EAX, Family, Model);

  GetX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
  bool Em64T = (EDX >> 29) & 0x1;
  bool HasSSE3 = (ECX & 0x1);

  union {
    unsigned u[3];
    char     c[12];
  } text;

  GetX86CpuIDAndInfo(0, &EAX, text.u+0, text.u+2, text.u+1);
  if (memcmp(text.c, "GenuineIntel", 12) == 0) {
    switch (Family) {
      case 3:
        return "i386";
      case 4:
        return "i486";
      case 5:
        switch (Model) {
        case 4:  return "pentium-mmx";
        default: return "pentium";
        }
      case 6:
        switch (Model) {
        case 1:  return "pentiumpro";
        case 3:
        case 5:
        case 6:  return "pentium2";
        case 7:
        case 8:
        case 10:
        case 11: return "pentium3";
        case 9:
        case 13: return "pentium-m";
        case 14: return "yonah";
        case 15:
        case 22: // Celeron M 540
          return "core2";
        case 23: // 45nm: Penryn , Wolfdale, Yorkfield (XE)
          return "penryn";
        default: return "i686";
        }
      case 15: {
        switch (Model) {
        case 3:  
        case 4:
        case 6: // same as 4, but 65nm
          return (Em64T) ? "nocona" : "prescott";
        case 26:
          return "corei7";
        case 28:
          return "atom";
        default:
          return (Em64T) ? "x86-64" : "pentium4";
        }
      }
        
    default:
      return "generic";
    }
  } else if (memcmp(text.c, "AuthenticAMD", 12) == 0) {
    // FIXME: this poorly matches the generated SubtargetFeatureKV table.  There
    // appears to be no way to generate the wide variety of AMD-specific targets
    // from the information returned from CPUID.
    switch (Family) {
      case 4:
        return "i486";
      case 5:
        switch (Model) {
        case 6:
        case 7:  return "k6";
        case 8:  return "k6-2";
        case 9:
        case 13: return "k6-3";
        default: return "pentium";
        }
      case 6:
        switch (Model) {
        case 4:  return "athlon-tbird";
        case 6:
        case 7:
        case 8:  return "athlon-mp";
        case 10: return "athlon-xp";
        default: return "athlon";
        }
      case 15:
        if (HasSSE3) {
          return "k8-sse3";
        } else {
          switch (Model) {
          case 1:  return "opteron";
          case 5:  return "athlon-fx"; // also opteron
          default: return "athlon64";
          }
        }
      case 16:
        return "amdfam10";
    default:
      return "generic";
    }
  } else {
    return "generic";
  }
#else
  return "generic";
#endif
}