[cpu-detection] Naming convention.

[asbirlea]

Summary

Follow-up to D20926 (committed as r271595, r271596).
This patch is in preparation for a substantial refactoring of the code.

No functionality changed.

[asbirlea]

• Update comment after clang format

[echristo]

Can you abandon this revision and start again while remembering to add
llvm-commits as you create the review please? Makes it much easier to make
sure everyone sees the mails.

Thanks!

[llvm-commits]

To elaborate a bit here: what's happening is that the update the list sees
is that you added the list and some reviewers, rather than an initial email
that contains the patch and your description of it so that people can scan
and look at patches without needing to go to phabricator.

• msg-20532-296.txt162 BDownload

lib/Support/Host.cpp

static ssize_t LLVM_ATTRIBUTE_UNUSED readCpuInfo(void *Buf, size_t Size) {
   return Ret;
 }
 #endif
 
 #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
+/// 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,
+static bool getX86CpuIDAndInfo(unsigned value, unsigned *rEAX, unsigned *rEBX,
                                unsigned *rECX, unsigned *rEDX) {
 #if defined(__GNUC__) || defined(__clang__)
 #if defined(__x86_64__) || defined(_M_AMD64) || defined(_M_X64)
   // 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)
#elif defined(_MSC_VER)
   *rECX = registers[2];
   *rEDX = registers[3];
   return false;
 #else
   return true;
 #endif
 }
 
-/// GetX86CpuIDAndInfoEx - Execute the specified cpuid with subleaf and return
+/// getX86CpuIDAndInfoEx - Execute the specified cpuid with subleaf and return
 /// the
 /// 4 values in the specified arguments.  If we can't run cpuid on the host,
 /// return true.
-static bool GetX86CpuIDAndInfoEx(unsigned value, unsigned subleaf,
+static bool getX86CpuIDAndInfoEx(unsigned value, unsigned subleaf,
                                  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"

 #else
   return true;
 #endif
 #else
   return true;
 #endif
 }
 
-static bool GetX86XCR0(unsigned *rEAX, unsigned *rEDX) {
+static bool getX86XCR0(unsigned *rEAX, unsigned *rEDX) {
 #if defined(__GNUC__)
   // Check xgetbv; this uses a .byte sequence instead of the instruction
   // directly because older assemblers do not include support for xgetbv and
   // there is no easy way to conditionally compile based on the assembler used.
   __asm__(".byte 0x0f, 0x01, 0xd0" : "=a"(*rEAX), "=d"(*rEDX) : "c"(0));
   return false;
 #elif defined(_MSC_FULL_VER) && defined(_XCR_XFEATURE_ENABLED_MASK)
   unsigned long long Result = _xgetbv(_XCR_XFEATURE_ENABLED_MASK);
   *rEAX = Result;
   *rEDX = Result >> 32;
   return false;
 #else
   return true;
 #endif
 }
 
-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)
+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
+      *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
+    *Model += ((EAX >> 16) & 0xf) << 4; // Bits 16 - 19
   }
 }
 
 StringRef sys::getHostCPUName() {
   unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
-  if (GetX86CpuIDAndInfo(0x1, &EAX, &EBX, &ECX, &EDX))
+  if (getX86CpuIDAndInfo(0x1, &EAX, &EBX, &ECX, &EDX))
     return "generic";
   unsigned Family = 0;
   unsigned Model = 0;
-  DetectX86FamilyModel(EAX, Family, Model);
+  detectX86FamilyModel(EAX, &Family, &Model);
 
   union {
     unsigned u[3];
     char c[12];
   } text;
 
   unsigned MaxLeaf;
-  GetX86CpuIDAndInfo(0, &MaxLeaf, text.u + 0, text.u + 2, text.u + 1);
+  getX86CpuIDAndInfo(0, &MaxLeaf, text.u + 0, text.u + 2, text.u + 1);
 
   bool HasMMX = (EDX >> 23) & 1;
   bool HasSSE = (EDX >> 25) & 1;
   bool HasSSE2 = (EDX >> 26) & 1;
   bool HasSSE3 = (ECX >> 0) & 1;
   bool HasSSSE3 = (ECX >> 9) & 1;
   bool HasSSE41 = (ECX >> 19) & 1;
   bool HasSSE42 = (ECX >> 20) & 1;
   bool HasMOVBE = (ECX >> 22) & 1;
   // If CPUID indicates support for XSAVE, XRESTORE and AVX, and XGETBV
   // indicates that the AVX registers will be saved and restored on context
   // switch, then we have full AVX support.
   const unsigned AVXBits = (1 << 27) | (1 << 28);
-  bool HasAVX = ((ECX & AVXBits) == AVXBits) && !GetX86XCR0(&EAX, &EDX) &&
+  bool HasAVX = ((ECX & AVXBits) == AVXBits) && !getX86XCR0(&EAX, &EDX) &&
                 ((EAX & 0x6) == 0x6);
   bool HasAVX512Save = HasAVX && ((EAX & 0xe0) == 0xe0);
   bool HasLeaf7 =
-      MaxLeaf >= 0x7 && !GetX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
+      MaxLeaf >= 0x7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
   bool HasADX = HasLeaf7 && ((EBX >> 19) & 1);
   bool HasAVX2 = HasAVX && HasLeaf7 && (EBX & 0x20);
   bool HasAVX512 = HasLeaf7 && HasAVX512Save && ((EBX >> 16) & 1);
 
-  GetX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
+  getX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
   bool Em64T = (EDX >> 29) & 0x1;
   bool HasTBM = (ECX >> 21) & 0x1;
 
   if (memcmp(text.c, "GenuineIntel", 12) == 0) {
     switch (Family) {
     case 3:
       return "i386";
     case 4:

 bool sys::getHostCPUFeatures(StringMap<bool> &Features) {
   unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
   unsigned MaxLevel;
   union {
     unsigned u[3];
     char c[12];
   } text;
 
-  if (GetX86CpuIDAndInfo(0, &MaxLevel, text.u + 0, text.u + 2, text.u + 1) ||
+  if (getX86CpuIDAndInfo(0, &MaxLevel, text.u + 0, text.u + 2, text.u + 1) ||
       MaxLevel < 1)
     return false;
 
-  GetX86CpuIDAndInfo(1, &EAX, &EBX, &ECX, &EDX);
+  getX86CpuIDAndInfo(1, &EAX, &EBX, &ECX, &EDX);
 
   Features["cmov"] = (EDX >> 15) & 1;
   Features["mmx"] = (EDX >> 23) & 1;
   Features["sse"] = (EDX >> 25) & 1;
   Features["sse2"] = (EDX >> 26) & 1;
   Features["sse3"] = (ECX >> 0) & 1;
   Features["ssse3"] = (ECX >> 9) & 1;
   Features["sse4.1"] = (ECX >> 19) & 1;
   Features["sse4.2"] = (ECX >> 20) & 1;
 
   Features["pclmul"] = (ECX >> 1) & 1;
   Features["cx16"] = (ECX >> 13) & 1;
   Features["movbe"] = (ECX >> 22) & 1;
   Features["popcnt"] = (ECX >> 23) & 1;
   Features["aes"] = (ECX >> 25) & 1;
   Features["rdrnd"] = (ECX >> 30) & 1;
 
   // If CPUID indicates support for XSAVE, XRESTORE and AVX, and XGETBV
   // indicates that the AVX registers will be saved and restored on context
   // switch, then we have full AVX support.
   bool HasAVXSave = ((ECX >> 27) & 1) && ((ECX >> 28) & 1) &&
-                    !GetX86XCR0(&EAX, &EDX) && ((EAX & 0x6) == 0x6);
+                    !getX86XCR0(&EAX, &EDX) && ((EAX & 0x6) == 0x6);
   Features["avx"] = HasAVXSave;
   Features["fma"] = HasAVXSave && (ECX >> 12) & 1;
   Features["f16c"] = HasAVXSave && (ECX >> 29) & 1;
 
   // Only enable XSAVE if OS has enabled support for saving YMM state.
   Features["xsave"] = HasAVXSave && (ECX >> 26) & 1;
 
   // AVX512 requires additional context to be saved by the OS.
   bool HasAVX512Save = HasAVXSave && ((EAX & 0xe0) == 0xe0);
 
   unsigned MaxExtLevel;
-  GetX86CpuIDAndInfo(0x80000000, &MaxExtLevel, &EBX, &ECX, &EDX);
+  getX86CpuIDAndInfo(0x80000000, &MaxExtLevel, &EBX, &ECX, &EDX);
 
   bool HasExtLeaf1 = MaxExtLevel >= 0x80000001 &&
-                     !GetX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
+                     !getX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
   Features["lzcnt"] = HasExtLeaf1 && ((ECX >> 5) & 1);
   Features["sse4a"] = HasExtLeaf1 && ((ECX >> 6) & 1);
   Features["prfchw"] = HasExtLeaf1 && ((ECX >> 8) & 1);
   Features["xop"] = HasExtLeaf1 && ((ECX >> 11) & 1) && HasAVXSave;
   Features["fma4"] = HasExtLeaf1 && ((ECX >> 16) & 1) && HasAVXSave;
   Features["tbm"] = HasExtLeaf1 && ((ECX >> 21) & 1);
   Features["mwaitx"] = HasExtLeaf1 && ((ECX >> 29) & 1);
 
   bool HasLeaf7 =
-      MaxLevel >= 7 && !GetX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
+      MaxLevel >= 7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
 
   // AVX2 is only supported if we have the OS save support from AVX.
   Features["avx2"] = HasAVXSave && HasLeaf7 && ((EBX >> 5) & 1);
 
   Features["fsgsbase"] = HasLeaf7 && ((EBX >> 0) & 1);
   Features["sgx"] = HasLeaf7 && ((EBX >> 2) & 1);
   Features["bmi"] = HasLeaf7 && ((EBX >> 3) & 1);
   Features["hle"] = HasLeaf7 && ((EBX >> 4) & 1);
bool sys::getHostCPUFeatures(StringMap<bool> &Features) {
   Features["avx512vl"] = HasLeaf7 && ((EBX >> 31) & 1) && HasAVX512Save;
 
   Features["prefetchwt1"] = HasLeaf7 && (ECX & 1);
   Features["avx512vbmi"] = HasLeaf7 && ((ECX >> 1) & 1) && HasAVX512Save;
   // Enable protection keys
   Features["pku"] = HasLeaf7 && ((ECX >> 4) & 1);
 
   bool HasLeafD = MaxLevel >= 0xd &&
-                  !GetX86CpuIDAndInfoEx(0xd, 0x1, &EAX, &EBX, &ECX, &EDX);
+                  !getX86CpuIDAndInfoEx(0xd, 0x1, &EAX, &EBX, &ECX, &EDX);
 
   // Only enable XSAVE if OS has enabled support for saving YMM state.
   Features["xsaveopt"] = HasAVXSave && HasLeafD && ((EAX >> 0) & 1);
   Features["xsavec"] = HasAVXSave && HasLeafD && ((EAX >> 1) & 1);
   Features["xsaves"] = HasAVXSave && HasLeafD && ((EAX >> 3) & 1);
 
   return true;
 }