-/// \brief This returns an integer containing an encoding of all the LLVM
-/// attributes found in the given attribute bitset. Any change to this encoding
-/// is a breaking change to bitcode compatibility.
-/// N.B. This should be used only by the bitcode writer!
-static uint64_t encodeLLVMAttributesForBitcode(AttributeSet Attrs,
- unsigned Index) {
- // FIXME: Remove in 4.0!
-
- // FIXME: It doesn't make sense to store the alignment information as an
- // expanded out value, we should store it as a log2 value. However, we can't
- // just change that here without breaking bitcode compatibility. If this ever
- // becomes a problem in practice, we should introduce new tag numbers in the
- // bitcode file and have those tags use a more efficiently encoded alignment
- // field.
-
- // Store the alignment in the bitcode as a 16-bit raw value instead of a 5-bit
- // log2 encoded value. Shift the bits above the alignment up by 11 bits.
- uint64_t EncodedAttrs = Attrs.Raw(Index) & 0xffff;
- if (Attrs.hasAttribute(Index, Attribute::Alignment))
- EncodedAttrs |= Attrs.getParamAlignment(Index) << 16;
- EncodedAttrs |= (Attrs.Raw(Index) & (0xfffffULL << 21)) << 11;
- return EncodedAttrs;
-}
-