The powers that be have decided that LLVM IR should now support 16-bit
"half precision" floating-point with a first-class type.
This patch adds basic IR support (but not codegen support).
llvm-svn: 146786
diff --git a/llvm/lib/VMCore/AsmWriter.cpp b/llvm/lib/VMCore/AsmWriter.cpp
index 4fb5fd3..3da47744 100644
--- a/llvm/lib/VMCore/AsmWriter.cpp
+++ b/llvm/lib/VMCore/AsmWriter.cpp
@@ -189,6 +189,7 @@
void TypePrinting::print(Type *Ty, raw_ostream &OS) {
switch (Ty->getTypeID()) {
case Type::VoidTyID: OS << "void"; break;
+ case Type::HalfTyID: OS << "half"; break;
case Type::FloatTyID: OS << "float"; break;
case Type::DoubleTyID: OS << "double"; break;
case Type::X86_FP80TyID: OS << "x86_fp80"; break;
@@ -708,31 +709,35 @@
}
if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
- if (&CFP->getValueAPF().getSemantics() == &APFloat::IEEEdouble ||
- &CFP->getValueAPF().getSemantics() == &APFloat::IEEEsingle) {
+ if (&CFP->getValueAPF().getSemantics() == &APFloat::IEEEhalf ||
+ &CFP->getValueAPF().getSemantics() == &APFloat::IEEEsingle ||
+ &CFP->getValueAPF().getSemantics() == &APFloat::IEEEdouble) {
// We would like to output the FP constant value in exponential notation,
// but we cannot do this if doing so will lose precision. Check here to
// make sure that we only output it in exponential format if we can parse
// the value back and get the same value.
//
bool ignored;
+ bool isHalf = &CFP->getValueAPF().getSemantics()==&APFloat::IEEEhalf;
bool isDouble = &CFP->getValueAPF().getSemantics()==&APFloat::IEEEdouble;
- double Val = isDouble ? CFP->getValueAPF().convertToDouble() :
- CFP->getValueAPF().convertToFloat();
- SmallString<128> StrVal;
- raw_svector_ostream(StrVal) << Val;
+ if (!isHalf) {
+ double Val = isDouble ? CFP->getValueAPF().convertToDouble() :
+ CFP->getValueAPF().convertToFloat();
+ SmallString<128> StrVal;
+ raw_svector_ostream(StrVal) << Val;
- // Check to make sure that the stringized number is not some string like
- // "Inf" or NaN, that atof will accept, but the lexer will not. Check
- // that the string matches the "[-+]?[0-9]" regex.
- //
- if ((StrVal[0] >= '0' && StrVal[0] <= '9') ||
- ((StrVal[0] == '-' || StrVal[0] == '+') &&
- (StrVal[1] >= '0' && StrVal[1] <= '9'))) {
- // Reparse stringized version!
- if (atof(StrVal.c_str()) == Val) {
- Out << StrVal.str();
- return;
+ // Check to make sure that the stringized number is not some string like
+ // "Inf" or NaN, that atof will accept, but the lexer will not. Check
+ // that the string matches the "[-+]?[0-9]" regex.
+ //
+ if ((StrVal[0] >= '0' && StrVal[0] <= '9') ||
+ ((StrVal[0] == '-' || StrVal[0] == '+') &&
+ (StrVal[1] >= '0' && StrVal[1] <= '9'))) {
+ // Reparse stringized version!
+ if (atof(StrVal.c_str()) == Val) {
+ Out << StrVal.str();
+ return;
+ }
}
}
// Otherwise we could not reparse it to exactly the same value, so we must
@@ -743,7 +748,7 @@
"assuming that double is 64 bits!");
char Buffer[40];
APFloat apf = CFP->getValueAPF();
- // Floats are represented in ASCII IR as double, convert.
+ // Halves and floats are represented in ASCII IR as double, convert.
if (!isDouble)
apf.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
&ignored);