diff options
| -rw-r--r-- | lib/Support/APFloat.cpp | 33 |
1 files changed, 14 insertions, 19 deletions
diff --git a/lib/Support/APFloat.cpp b/lib/Support/APFloat.cpp index 388bbd7..d05c24e 100644 --- a/lib/Support/APFloat.cpp +++ b/lib/Support/APFloat.cpp @@ -1556,32 +1556,27 @@ APFloat::convertFromUnsignedParts(const integerPart *src, unsigned int srcCount, roundingMode rounding_mode) { - unsigned int dstCount; - lostFraction lost_fraction; + unsigned int omsb, precision, dstCount; integerPart *dst; + lostFraction lost_fraction; category = fcNormal; - exponent = semantics->precision - 1; - + omsb = APInt::tcMSB(src, srcCount) + 1; dst = significandParts(); dstCount = partCount(); + precision = semantics->precision; - /* We need to capture the non-zero most significant parts. */ - while (srcCount > dstCount && src[srcCount - 1] == 0) - srcCount--; - - /* Copy the bit image of as many parts as we can. If we are wider, - zero-out remaining parts. */ - if (dstCount >= srcCount) { - APInt::tcAssign(dst, src, srcCount); - while (srcCount < dstCount) - dst[srcCount++] = 0; - lost_fraction = lfExactlyZero; - } else { - exponent += (srcCount - dstCount) * integerPartWidth; - APInt::tcAssign(dst, src + (srcCount - dstCount), dstCount); + /* We want the most significant PRECISON bits of SRC. There may not + be that many; extract what we can. */ + if (precision <= omsb) { + exponent = omsb - 1; lost_fraction = lostFractionThroughTruncation(src, srcCount, - dstCount * integerPartWidth); + omsb - precision); + APInt::tcExtract(dst, dstCount, src, precision, omsb - precision); + } else { + exponent = precision - 1; + lost_fraction = lfExactlyZero; + APInt::tcExtract(dst, dstCount, src, omsb, 0); } return normalize(rounding_mode, lost_fraction); |