Reverting back to the fallback instead of using popcnt; this instruction doesn't exist on all CPU architectures. Fixes PR14982

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172734 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Aaron Ballman 2013-01-17 18:27:30 +00:00
parent 792b123338
commit 67828056dd

View File

@ -303,8 +303,6 @@ inline unsigned CountTrailingOnes_64(uint64_t Value) {
inline unsigned CountPopulation_32(uint32_t Value) {
#if __GNUC__ >= 4
return __builtin_popcount(Value);
#elif defined(_MSC_VER)
return __popcnt(Value);
#else
uint32_t v = Value - ((Value >> 1) & 0x55555555);
v = (v & 0x33333333) + ((v >> 2) & 0x33333333);