1 //===-- X86Subtarget.cpp - X86 Subtarget Information ------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Nate Begeman and is distributed under the
6 // University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the X86 specific subclass of TargetSubtarget.
12 //===----------------------------------------------------------------------===//
14 #include "X86Subtarget.h"
15 #include "llvm/Module.h"
16 #include "X86GenSubtarget.inc"
19 /// GetCpuIDAndInfo - Execute the specified cpuid and return the 4 values in the
20 /// specified arguments. If we can't run cpuid on the host, return true.
21 static bool GetCpuIDAndInfo(unsigned value, unsigned *rEAX, unsigned *rEBX,
22 unsigned *rECX, unsigned *rEDX) {
23 #if defined(i386) || defined(__i386__) || defined(__x86__) || defined(_M_IX86)
25 asm ("pushl\t%%ebx\n\t"
27 "movl\t%%ebx, %%esi\n\t"
35 #elif defined(_MSC_VER)
40 mov dword ptr [esi],eax
42 mov dword ptr [esi],ebx
44 mov dword ptr [esi],ecx
46 mov dword ptr [esi],edx
54 static const char *GetCurrentX86CPU() {
55 unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
56 if (GetCpuIDAndInfo(0x1, &EAX, &EBX, &ECX, &EDX))
58 unsigned Family = (EAX & (0xffffffff >> (32 - 4)) << 8) >> 8; // Bits 8 - 11
59 unsigned Model = (EAX & (0xffffffff >> (32 - 4)) << 4) >> 4; // Bits 4 - 7
60 GetCpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
61 bool Em64T = EDX & (1 << 29);
68 GetCpuIDAndInfo(0, &EAX, text.u+0, text.u+2, text.u+1);
69 if (memcmp(text.c, "GenuineIntel", 12) == 0) {
77 case 4: return "pentium-mmx";
78 default: return "pentium";
82 case 1: return "pentiumpro";
85 case 6: return "pentium2";
89 case 11: return "pentium3";
91 case 13: return "pentium-m";
92 case 14: return "yonah";
93 default: return "i686";
99 return (Em64T) ? "nocona" : "prescott";
101 return (Em64T) ? "x86-64" : "pentium4";
108 } else if (memcmp(text.c, "AuthenticAMD", 12) == 0) {
109 // FIXME: this poorly matches the generated SubtargetFeatureKV table. There
110 // appears to be no way to generate the wide variety of AMD-specific targets
111 // from the information returned from CPUID.
119 case 8: return "k6-2";
121 case 13: return "k6-3";
122 default: return "pentium";
126 case 4: return "athlon-tbird";
129 case 8: return "athlon-mp";
130 case 10: return "athlon-xp";
131 default: return "athlon";
135 case 5: return "athlon-fx"; // also opteron
136 default: return "athlon64";
147 X86Subtarget::X86Subtarget(const Module &M, const std::string &FS) {
149 // FIXME: this is a known good value for Yonah. Not sure about others.
150 MinRepStrSizeThreshold = 128;
151 X86SSELevel = NoMMXSSE;
152 X863DNowLevel = NoThreeDNow;
155 // Determine default and user specified characteristics
156 std::string CPU = GetCurrentX86CPU();
158 // Parse features string.
159 ParseSubtargetFeatures(FS, CPU);
161 // Default to ELF unless otherwise specified.
164 // Set the boolean corresponding to the current target triple, or the default
165 // if one cannot be determined, to true.
166 const std::string& TT = M.getTargetTriple();
167 if (TT.length() > 5) {
168 if (TT.find("cygwin") != std::string::npos ||
169 TT.find("mingw") != std::string::npos)
170 TargetType = isCygwin;
171 else if (TT.find("darwin") != std::string::npos)
172 TargetType = isDarwin;
173 else if (TT.find("win32") != std::string::npos)
174 TargetType = isWindows;
175 } else if (TT.empty()) {
176 #if defined(__CYGWIN__) || defined(__MINGW32__)
177 TargetType = isCygwin;
178 #elif defined(__APPLE__)
179 TargetType = isDarwin;
180 #elif defined(_WIN32)
181 TargetType = isWindows;
185 if (TargetType == isDarwin)