Issue with getting unsigned Constant from APInt

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1

Hi there,

I have been trying to obtain a Constant from an APInt using

auto maskConstant = llvm::ConstantInt::get(intTy, maskPiece);

where intTy is a IntergerType pointer (64-bit) and maskPiece is an APInt object. However, if maskPiece has the a big value say
18374686479671623680, which is 1111111100000000000000000000000000000000000000000000000000000000. The constant will return a negative value -72057594037927936, which looks it is always converted to a signed integer. How can i keep it as unsigned?

I have also tried maskConstant = llvm::ConstantInt::get(intTy, maskPiece.getZExtValue(), false); or maskConstant = llvm::ConstantInt::get(intTy, maskPiece.getZExtValue(), false);, both returned the same negative value. Any help will be appreciated.

Best regards,

Leo Z

2

"i64 18374686479671623680" and "i64 -72057594037927936" are actually the same value in LLVM IR. dump() prints the signed version, but that's just for convenience (since "i64 -1" is easier to read). Integer operations have separate signed and unsigned versions where it's relevant (e.g. sdiv vs. udiv).

-Eli