Reapply r158337, this time properly protect Darwin/PPC host CPU use with __ppc__.

Original commit message:
Move PPC host-CPU detection logic from PPCSubtarget into sys::getHostCPUName().

Both the new Linux functionality and the old Darwin functions have been moved.
This change also allows this information to be queried directly by clang and
other frontends (clang, for example, will now have real -mcpu=native support).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158349 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 130 insertions, 0 deletions

diff --git a/lib/Support/Host.cpp b/lib/Support/Host.cpp
index 1ad7852dd9..d48c5265a4 100644
--- a/lib/Support/Host.cpp
+++ b/lib/Support/Host.cpp
@@ -11,7 +11,12 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Support/DataStream.h"
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/Host.h"
+#include "llvm/Support/raw_ostream.h"
 #include "llvm/Config/config.h"
 #include <string.h>
 
@@ -25,6 +30,12 @@
 #ifdef _MSC_VER
 #include <intrin.h>
 #endif
+#if defined(__APPLE__) && (defined(__ppc__) || defined(__powerpc__))
+#include <mach/mach.h>
+#include <mach/mach_host.h>
+#include <mach/host_info.h>
+#include <mach/machine.h>
+#endif
 
 //===----------------------------------------------------------------------===//
 //
@@ -320,6 +331,125 @@ std::string sys::getHostCPUName() {
   }
   return "generic";
 }
+#elif defined(__APPLE__) && (defined(__ppc__) || defined(__powerpc__))
+std::string sys::getHostCPUName() {
+  host_basic_info_data_t hostInfo;
+  mach_msg_type_number_t infoCount;
+
+  infoCount = HOST_BASIC_INFO_COUNT;
+  host_info(mach_host_self(), HOST_BASIC_INFO, (host_info_t)&hostInfo, 
+            &infoCount);
+            
+  if (hostInfo.cpu_type != CPU_TYPE_POWERPC) return "generic";
+
+  switch(hostInfo.cpu_subtype) {
+  case CPU_SUBTYPE_POWERPC_601:   return "601";
+  case CPU_SUBTYPE_POWERPC_602:   return "602";
+  case CPU_SUBTYPE_POWERPC_603:   return "603";
+  case CPU_SUBTYPE_POWERPC_603e:  return "603e";
+  case CPU_SUBTYPE_POWERPC_603ev: return "603ev";
+  case CPU_SUBTYPE_POWERPC_604:   return "604";
+  case CPU_SUBTYPE_POWERPC_604e:  return "604e";
+  case CPU_SUBTYPE_POWERPC_620:   return "620";
+  case CPU_SUBTYPE_POWERPC_750:   return "750";
+  case CPU_SUBTYPE_POWERPC_7400:  return "7400";
+  case CPU_SUBTYPE_POWERPC_7450:  return "7450";
+  case CPU_SUBTYPE_POWERPC_970:   return "970";
+  default: ;
+  }
+  
+  return "generic";
+}
+#elif defined(__linux__) && (defined(__ppc__) || defined(__powerpc__))
+std::string sys::getHostCPUName() {
+  // Access to the Processor Version Register (PVR) on PowerPC is privileged,
+  // and so we must use an operating-system interface to determine the current
+  // processor type. On Linux, this is exposed through the /proc/cpuinfo file.
+  const char *generic = "generic";
+
+  // Note: We cannot mmap /proc/cpuinfo here and then process the resulting
+  // memory buffer because the 'file' has 0 size (it can be read from only
+  // as a stream).
+
+  std::string Err;
+  DataStreamer *DS = getDataFileStreamer("/proc/cpuinfo", &Err);
+  if (!DS) {
+    DEBUG(dbgs() << "Unable to open /proc/cpuinfo: " << Err << "\n");
+    return generic;
+  }
+
+  // The cpu line is second (after the 'processor: 0' line), so if this
+  // buffer is too small then something has changed (or is wrong).
+  char buffer[1024];
+  size_t CPUInfoSize = DS->GetBytes((unsigned char*) buffer, sizeof(buffer));
+  delete DS;
+
+  const char *CPUInfoStart = buffer;
+  const char *CPUInfoEnd = buffer + CPUInfoSize;
+
+  const char *CIP = CPUInfoStart;
+
+  const char *CPUStart = 0;
+  size_t CPULen = 0;
+
+  // We need to find the first line which starts with cpu, spaces, and a colon.
+  // After the colon, there may be some additional spaces and then the cpu type.
+  while (CIP < CPUInfoEnd && CPUStart == 0) {
+    if (CIP < CPUInfoEnd && *CIP == '\n')
+      ++CIP;
+
+    if (CIP < CPUInfoEnd && *CIP == 'c') {
+      ++CIP;
+      if (CIP < CPUInfoEnd && *CIP == 'p') {
+        ++CIP;
+        if (CIP < CPUInfoEnd && *CIP == 'u') {
+          ++CIP;
+          while (CIP < CPUInfoEnd && (*CIP == ' ' || *CIP == '\t'))
+            ++CIP;
+  
+          if (CIP < CPUInfoEnd && *CIP == ':') {
+            ++CIP;
+            while (CIP < CPUInfoEnd && (*CIP == ' ' || *CIP == '\t'))
+              ++CIP;
+  
+            if (CIP < CPUInfoEnd) {
+              CPUStart = CIP;
+              while (CIP < CPUInfoEnd && (*CIP != ' ' && *CIP != '\t' &&
+                                          *CIP != ',' && *CIP != '\n'))
+                ++CIP;
+              CPULen = CIP - CPUStart;
+            }
+          }
+        }
+      }
+    }
+
+    if (CPUStart == 0)
+      while (CIP < CPUInfoEnd && *CIP != '\n')
+        ++CIP;
+  }
+
+  if (CPUStart == 0)
+    return generic;
+
+  return StringSwitch<const char *>(StringRef(CPUStart, CPULen))
+    .Case("604e", "604e")
+    .Case("604", "604")
+    .Case("7400", "7400")
+    .Case("7410", "7400")
+    .Case("7447", "7400")
+    .Case("7455", "7450")
+    .Case("G4", "g4")
+    .Case("POWER4", "g4")
+    .Case("PPC970FX", "970")
+    .Case("PPC970MP", "970")
+    .Case("G5", "g5")
+    .Case("POWER5", "g5")
+    .Case("A2", "a2")
+    .Case("POWER6", "pwr6")
+    .Case("POWER7", "pwr7")
+    .Default(generic);
+}
 #else
 std::string sys::getHostCPUName() {
   return "generic";