llvm

75a354ba - [InstCombine] Use ComputeNumSignBits in isKnownExactCastIntToFP (#190235)

[InstCombine] Use ComputeNumSignBits in isKnownExactCastIntToFP (#190235) For signed int-to-FP casts, ComputeNumSignBits can prove exactness where computeKnownBits cannot -- e.g. through ashr(shl x, a), b where sign propagation is tracked precisely but individual known bits are all unknown.