[Support] Handle SPARC in sys::getHostCPUName

[ro]

Summary

While working on D118450, I noticed that sys::getHostCPUName lacks SPARC support.

This patch implements it. The code is taken from/inspired by GCC's gcc/config/sparc/driver-sparc.cc. There's one caveat: since LLVM, unlike GCC, doesn't support the SPARC-M7, -S7, and -M8 CPUs, I map all those to the latest supported one (UltraSparc T5/niagara4).

Tested on sparcv9-sun-solaris2.11 and sparc64-unknown-linux-gnu by running savcov --version on

• Netra SPARC S7-2 (SPARC-S7, Solaris 11.4)
• SPARC T5-2 (SPARC T5, Solaris 11.4)
• SPARC Enterprise T5220 (UltraSPARC T2, Solaris 11.3)
• SPARC T5 (UltraSPARC T5, Debian sid)
• SPARC T3 (UltraSPARC T3, Debian sid)

[ro]

Ping? It's been a week. Thanks.

[efriedma]

LGTM, but I don't really know enough to review the Solaris-specific bits.

[MaskRay]

The code style looks good to me, but I cannot verify the list. @glaubitz should have sparc machines and perform some verification.

[ro]

In D130272#3680084, @efriedma wrote:

LGTM, but I don't really know enough to review the Solaris-specific bits.

They are taken straight from my 2011 GCC patch (and follow-ups) that introduced the code in gcc/config/sparc/driver-sparc.cc. I've just adapted them to match LLVM coding conventions as far as necessary.

In D130272#3680192, @MaskRay wrote:

The code style looks good to me, but I cannot verify the list. @glaubitz should have sparc machines and perform some verification.

Both lists are straight from driver-sparc.cc, with the noted exceptions of not emitting CPU types LLVM doesn't support (yet?). On the Linux/sparc64 side I've meanwhile set up a Debian 11 LDom on a SPARC Enterprise T5220, where the values also match. In addition, I've looked at current Linux kernel sources (arch/sparc/kernel/cpu.c, arch/sparc/include/asm/spitfire.h) and found three unhandled CPUs:

• SPARC-M6: might be handled as niagara4; GCC knows nothing about this
• SPARC-SN: never even heard of this
• SPARC64-X: Fujitsu SPARC CPU, no idea how to handle this either

Unless someone else can chime in on those, I'd leave them alone.

[glaubitz]

In D130272#3680192, @MaskRay wrote:

The code style looks good to me, but I cannot verify the list. @glaubitz should have sparc machines and perform some verification.

@ro tested it on the same machines from the GCC compile farm that I would have used. So I think it's not necessary for me to test the changes as well. :-)

llvm/include/llvm/Support/Host.h

namespace sys {
   int getHostNumPhysicalCores();
 
   namespace detail {
   /// Helper functions to extract HostCPUName from /proc/cpuinfo on linux.
   StringRef getHostCPUNameForPowerPC(StringRef ProcCpuinfoContent);
   StringRef getHostCPUNameForARM(StringRef ProcCpuinfoContent);
   StringRef getHostCPUNameForS390x(StringRef ProcCpuinfoContent);
   StringRef getHostCPUNameForRISCV(StringRef ProcCpuinfoContent);
+  StringRef getHostCPUNameForSPARC(StringRef ProcCpuinfoContent);
   StringRef getHostCPUNameForBPF();
 
   /// Helper functions to extract CPU details from CPUID on x86.
   namespace x86 {
   enum class VendorSignatures {
     UNKNOWN,
     GENUINE_INTEL,
     AUTHENTIC_AMD,

llvm/lib/Support/CMakeLists.txt

elseif( CMAKE_HOST_UNIX )
   endif()
   if( LLVM_ENABLE_THREADS AND (HAVE_LIBATOMIC OR HAVE_CXX_LIBATOMICS64) )
     set(system_libs ${system_libs} atomic)
   endif()
   set(system_libs ${system_libs} ${LLVM_PTHREAD_LIB})
   if( UNIX AND NOT (BEOS OR HAIKU) )
     set(system_libs ${system_libs} m)
   endif()
+  if( UNIX AND ${CMAKE_SYSTEM_NAME} MATCHES "SunOS" )
+    set(system_libs ${system_libs} kstat)
+  endif()
   if( FUCHSIA )
     set(system_libs ${system_libs} zircon)
   endif()
   if ( HAIKU )
     add_definitions(-D_BSD_SOURCE)
     set(system_libs ${system_libs} bsd)
   endif()
 endif( MSVC OR MINGW )

llvm/lib/Support/Host.cpp

 #include <mach/mach_host.h>
 #include <mach/machine.h>
 #include <sys/param.h>
 #include <sys/sysctl.h>
 #endif
 #ifdef _AIX
 #include <sys/systemcfg.h>
 #endif
+#if defined(__sun__) && defined(__svr4__)
+#include <kstat.h>
+#endif
 
 #define DEBUG_TYPE "host-detection"
 
 //===----------------------------------------------------------------------===//
 //
 //  Implementations of the CPU detection routines
 //
 //===----------------------------------------------------------------------===//
#if __riscv_xlen == 64
   return "generic-rv64";
 #elif __riscv_xlen == 32
   return "generic-rv32";
 #else
 #error "Unhandled value of __riscv_xlen"
 #endif
 #endif
 }
+#elif defined(__sparc__)
+#if defined(__linux__)
+StringRef sys::detail::getHostCPUNameForSPARC(StringRef ProcCpuinfoContent) {
+  SmallVector<StringRef> Lines;
+  ProcCpuinfoContent.split(Lines, "\n");
+
+  // Look for cpu line to determine cpu name
+  StringRef Cpu;
+  for (unsigned I = 0, E = Lines.size(); I != E; ++I) {
+    if (Lines[I].startswith("cpu")) {
+      Cpu = Lines[I].substr(5).ltrim("\t :");
+      break;
+    }
+  }
+
+  return StringSwitch<const char *>(Cpu)
+      .StartsWith("SuperSparc", "supersparc")
+      .StartsWith("HyperSparc", "hypersparc")
+      .StartsWith("SpitFire", "ultrasparc")
+      .StartsWith("BlackBird", "ultrasparc")
+      .StartsWith("Sabre", " ultrasparc")
+      .StartsWith("Hummingbird", "ultrasparc")
+      .StartsWith("Cheetah", "ultrasparc3")
+      .StartsWith("Jalapeno", "ultrasparc3")
+      .StartsWith("Jaguar", "ultrasparc3")
+      .StartsWith("Panther", "ultrasparc3")
+      .StartsWith("Serrano", "ultrasparc3")
+      .StartsWith("UltraSparc T1", "niagara")
+      .StartsWith("UltraSparc T2", "niagara2")
+      .StartsWith("UltraSparc T3", "niagara3")
+      .StartsWith("UltraSparc T4", "niagara4")
+      .StartsWith("UltraSparc T5", "niagara4")
+      .StartsWith("LEON", "leon3")
+      // niagara7/m8 not supported by LLVM yet.
+      .StartsWith("SPARC-M7", "niagara4" /* "niagara7" */)
+      .StartsWith("SPARC-S7", "niagara4" /* "niagara7" */)
+      .StartsWith("SPARC-M8", "niagara4" /* "m8" */)
+      .Default("generic");
+}
+#endif
+
+StringRef sys::getHostCPUName() {
+#if defined(__linux__)
+  std::unique_ptr<llvm::MemoryBuffer> P = getProcCpuinfoContent();
+  StringRef Content = P ? P->getBuffer() : "";
+  return detail::getHostCPUNameForSPARC(Content);
+#elif defined(__sun__) && defined(__svr4__)
+  char *buf = NULL;
+  kstat_ctl_t *kc;
+  kstat_t *ksp;
+  kstat_named_t *brand = NULL;
+
+  kc = kstat_open();
+  if (kc != NULL) {
+    ksp = kstat_lookup(kc, const_cast<char *>("cpu_info"), -1, NULL);
+    if (ksp != NULL && kstat_read(kc, ksp, NULL) != -1 &&
+        ksp->ks_type == KSTAT_TYPE_NAMED)
+      brand =
+          (kstat_named_t *)kstat_data_lookup(ksp, const_cast<char *>("brand"));
+    if (brand != NULL && brand->data_type == KSTAT_DATA_STRING)
+      buf = KSTAT_NAMED_STR_PTR(brand);
+  }
+  kstat_close(kc);
+
+  return StringSwitch<const char *>(buf)
+      .Case("TMS390S10", "supersparc") // Texas Instruments microSPARC I
+      .Case("TMS390Z50", "supersparc") // Texas Instruments SuperSPARC I
+      .Case("TMS390Z55",
+            "supersparc") // Texas Instruments SuperSPARC I with SuperCache
+      .Case("MB86904", "supersparc") // Fujitsu microSPARC II
+      .Case("MB86907", "supersparc") // Fujitsu TurboSPARC
+      .Case("RT623", "hypersparc")   // Ross hyperSPARC
+      .Case("RT625", "hypersparc")
+      .Case("RT626", "hypersparc")
+      .Case("UltraSPARC-I", "ultrasparc")
+      .Case("UltraSPARC-II", "ultrasparc")
+      .Case("UltraSPARC-IIe", "ultrasparc")
+      .Case("UltraSPARC-IIi", "ultrasparc")
+      .Case("SPARC64-III", "ultrasparc")
+      .Case("SPARC64-IV", "ultrasparc")
+      .Case("UltraSPARC-III", "ultrasparc3")
+      .Case("UltraSPARC-III+", "ultrasparc3")
+      .Case("UltraSPARC-IIIi", "ultrasparc3")
+      .Case("UltraSPARC-IIIi+", "ultrasparc3")
+      .Case("UltraSPARC-IV", "ultrasparc3")
+      .Case("UltraSPARC-IV+", "ultrasparc3")
+      .Case("SPARC64-V", "ultrasparc3")
+      .Case("SPARC64-VI", "ultrasparc3")
+      .Case("SPARC64-VII", "ultrasparc3")
+      .Case("UltraSPARC-T1", "niagara")
+      .Case("UltraSPARC-T2", "niagara2")
+      .Case("UltraSPARC-T2", "niagara2")
+      .Case("UltraSPARC-T2+", "niagara2")
+      .Case("SPARC-T3", "niagara3")
+      .Case("SPARC-T4", "niagara4")
+      .Case("SPARC-T5", "niagara4")
+      // niagara7/m8 not supported by LLVM yet.
+      .Case("SPARC-M7", "niagara4" /* "niagara7" */)
+      .Case("SPARC-S7", "niagara4" /* "niagara7" */)
+      .Case("SPARC-M8", "niagara4" /* "m8" */)
+      .Default("generic");
+#else
+  return "generic";
+#endif
+}
 #else
 StringRef sys::getHostCPUName() { return "generic"; }
 namespace llvm {
 namespace sys {
 namespace detail {
 namespace x86 {
 
 VendorSignatures getVendorSignature(unsigned *MaxLeaf) {