[llvm] InstCombine/Demanded: simplify srem case (NFC) (PR #110260)

[Nikita Popov via llvm-commits]

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@@ -861,30 +861,15 @@ Value *InstCombinerImpl::SimplifyDemandedUseBits(Instruction *I,
     // X % -1 demands all the bits because we don't want to introduce
     // INT_MIN % -1 (== undef) by accident.
     if (match(I->getOperand(1), m_APInt(Rem)) && !Rem->isAllOnes()) {
-      APInt RA = Rem->abs();
-      if (RA.isPowerOf2()) {
-        if (DemandedMask.ult(RA))    // srem won't affect demanded bits
+      if (Rem->isPowerOf2()) {
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nikic wrote:

I'd merge this condition into the preceding if. And actually we can drop `!isAllOnes()` as it's mutually exclusive with `isPowerOf2()`. (But wasn't previously as abs(-1) = 1, which is a power of 2.)

https://github.com/llvm/llvm-project/pull/110260