[ProfileData] Remove getHostEndianness (NFC)

With the recent redefinition of llvm::endianness::native, it is equal
to either llvm::endianness::big or llvm::endianness::little depending
on the host endianness.  Since getHostEndianness just returns
llvm::endianness::native, this patch removes the function and
"constant propagates" llvm::endianness:native.

Author: kazutakahirata

llvm/include/llvm/ProfileData/InstrProf.h

@@ -949,10 +949,6 @@ void InstrProfRecord::reserveSites(uint32_t ValueKind, uint32_t NumValueSites) {
   getOrCreateValueSitesForKind(ValueKind).reserve(NumValueSites);
 }
 
-inline support::endianness getHostEndianness() {
-  return sys::IsLittleEndianHost ? support::little : support::big;
-}
-
 // Include definitions for value profile data
 #define INSTR_PROF_VALUE_PROF_DATA
 #include "llvm/ProfileData/InstrProfData.inc"

llvm/include/llvm/ProfileData/InstrProfReader.h

@@ -413,10 +413,9 @@ class RawInstrProfReader : public InstrProfReader {
   }
 
   support::endianness getDataEndianness() const {
-    support::endianness HostEndian = getHostEndianness();
     if (!ShouldSwapBytes)
-      return HostEndian;
-    if (HostEndian == support::little)
+      return llvm::endianness::native;
+    if (llvm::endianness::native == llvm::endianness::little)
       return support::big;
     else
       return support::little;

llvm/lib/ProfileData/InstrProf.cpp

@@ -989,7 +989,7 @@ void ValueProfRecord::swapBytes(support::endianness Old,
   if (Old == New)
     return;
 
-  if (getHostEndianness() != Old) {
+  if (llvm::endianness::native != Old) {
     sys::swapByteOrder<uint32_t>(NumValueSites);
     sys::swapByteOrder<uint32_t>(Kind);
   }
@@ -1001,7 +1001,7 @@ void ValueProfRecord::swapBytes(support::endianness Old,
     sys::swapByteOrder<uint64_t>(VD[I].Value);
     sys::swapByteOrder<uint64_t>(VD[I].Count);
   }
-  if (getHostEndianness() == Old) {
+  if (llvm::endianness::native == Old) {
     sys::swapByteOrder<uint32_t>(NumValueSites);
     sys::swapByteOrder<uint32_t>(Kind);
   }
@@ -1086,29 +1086,29 @@ ValueProfData::getValueProfData(const unsigned char *D,
 void ValueProfData::swapBytesToHost(support::endianness Endianness) {
   using namespace support;
 
-  if (Endianness == getHostEndianness())
+  if (Endianness == llvm::endianness::native)
     return;
 
   sys::swapByteOrder<uint32_t>(TotalSize);
   sys::swapByteOrder<uint32_t>(NumValueKinds);
 
   ValueProfRecord *VR = getFirstValueProfRecord(this);
   for (uint32_t K = 0; K < NumValueKinds; K++) {
-    VR->swapBytes(Endianness, getHostEndianness());
+    VR->swapBytes(Endianness, llvm::endianness::native);
     VR = getValueProfRecordNext(VR);
   }
 }
 
 void ValueProfData::swapBytesFromHost(support::endianness Endianness) {
   using namespace support;
 
-  if (Endianness == getHostEndianness())
+  if (Endianness == llvm::endianness::native)
     return;
 
   ValueProfRecord *VR = getFirstValueProfRecord(this);
   for (uint32_t K = 0; K < NumValueKinds; K++) {
     ValueProfRecord *NVR = getValueProfRecordNext(VR);
-    VR->swapBytes(getHostEndianness(), Endianness);
+    VR->swapBytes(llvm::endianness::native, Endianness);
     VR = NVR;
   }
   sys::swapByteOrder<uint32_t>(TotalSize);