Implement APInt <-> APFloat conversion for IEEE 128-bit floats.
This fixes PR2555
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79677 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/APFloat.cpp b/lib/Support/APFloat.cpp
index a22ec15..2d8df5e 100644
--- a/lib/Support/APFloat.cpp
+++ b/lib/Support/APFloat.cpp
@@ -2710,6 +2710,42 @@
}
APInt
+APFloat::convertQuadrupleAPFloatToAPInt() const
+{
+ assert(semantics == (const llvm::fltSemantics*)&IEEEquad);
+ assert (partCount()==2);
+
+ uint64_t myexponent, mysignificand, mysignificand2;
+
+ if (category==fcNormal) {
+ myexponent = exponent+16383; //bias
+ mysignificand = significandParts()[0];
+ mysignificand2 = significandParts()[1];
+ if (myexponent==1 && !(mysignificand2 & 0x1000000000000LL))
+ myexponent = 0; // denormal
+ } else if (category==fcZero) {
+ myexponent = 0;
+ mysignificand = mysignificand2 = 0;
+ } else if (category==fcInfinity) {
+ myexponent = 0x7fff;
+ mysignificand = mysignificand2 = 0;
+ } else {
+ assert(category == fcNaN && "Unknown category!");
+ myexponent = 0x7fff;
+ mysignificand = significandParts()[0];
+ mysignificand2 = significandParts()[1];
+ }
+
+ uint64_t words[2];
+ words[0] = mysignificand;
+ words[1] = ((uint64_t)(sign & 1) << 63) |
+ ((myexponent & 0x7fff) << 48) |
+ (mysignificand & 0xffffffffffffLL);
+
+ return APInt(128, 2, words);
+}
+
+APInt
APFloat::convertDoubleAPFloatToAPInt() const
{
assert(semantics == (const llvm::fltSemantics*)&IEEEdouble);
@@ -2777,10 +2813,13 @@
{
if (semantics == (const llvm::fltSemantics*)&IEEEsingle)
return convertFloatAPFloatToAPInt();
-
+
if (semantics == (const llvm::fltSemantics*)&IEEEdouble)
return convertDoubleAPFloatToAPInt();
+ if (semantics == (const llvm::fltSemantics*)&IEEEquad)
+ return convertQuadrupleAPFloatToAPInt();
+
if (semantics == (const llvm::fltSemantics*)&PPCDoubleDouble)
return convertPPCDoubleDoubleAPFloatToAPInt();
@@ -2897,6 +2936,46 @@
}
void
+APFloat::initFromQuadrupleAPInt(const APInt &api)
+{
+ assert(api.getBitWidth()==128);
+ uint64_t i1 = api.getRawData()[0];
+ uint64_t i2 = api.getRawData()[1];
+ uint64_t myexponent = (i2 >> 48) & 0x7fff;
+ uint64_t mysignificand = i1;
+ uint64_t mysignificand2 = i2 & 0xffffffffffffLL;
+
+ initialize(&APFloat::IEEEquad);
+ assert(partCount()==2);
+
+ sign = static_cast<unsigned int>(i2>>63);
+ if (myexponent==0 &&
+ (mysignificand==0 && mysignificand2==0)) {
+ // exponent, significand meaningless
+ category = fcZero;
+ } else if (myexponent==0x7fff &&
+ (mysignificand==0 && mysignificand2==0)) {
+ // exponent, significand meaningless
+ category = fcInfinity;
+ } else if (myexponent==0x7fff &&
+ (mysignificand!=0 || mysignificand2 !=0)) {
+ // exponent meaningless
+ category = fcNaN;
+ significandParts()[0] = mysignificand;
+ significandParts()[1] = mysignificand2;
+ } else {
+ category = fcNormal;
+ exponent = myexponent - 16383;
+ significandParts()[0] = mysignificand;
+ significandParts()[1] = mysignificand2;
+ if (myexponent==0) // denormal
+ exponent = -16382;
+ else
+ significandParts()[1] |= 0x1000000000000LL; // integer bit
+ }
+}
+
+void
APFloat::initFromDoubleAPInt(const APInt &api)
{
assert(api.getBitWidth()==64);
@@ -2975,8 +3054,9 @@
return initFromDoubleAPInt(api);
else if (api.getBitWidth()==80)
return initFromF80LongDoubleAPInt(api);
- else if (api.getBitWidth()==128 && !isIEEE)
- return initFromPPCDoubleDoubleAPInt(api);
+ else if (api.getBitWidth()==128)
+ return (isIEEE ?
+ initFromQuadrupleAPInt(api) : initFromPPCDoubleDoubleAPInt(api));
else
llvm_unreachable(0);
}