[PATCH] D30525: [APInt] Add setLowBits/setHighBits methods to APInt.

[Hans Wennborg via Phabricator via llvm-commits]

hans added inline comments.


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Comment at: lib/Support/APInt.cpp:575
+  if (loWord == hiWord) {
+    // Set bits are all within the same word, create a [loBit,hiBit) mask.
+    loMask >>= (APINT_BITS_PER_WORD - (hiBit - loBit));
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This comment isn't really true anymore since you're only creating loMask (and when it gets left-shifted later, the name loMask isn't really appropriate anymore).

It might make sense to keep these two cases separate and let the compiler handle the redundant instructions.

I see the logic is changing a little, with hiWord now referring to whichWord(hiBit) instead of whichWord(hiBit - 1). Did you find a bug, or is this just trying to make the code clearer?


https://reviews.llvm.org/D30525