maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[InstCombine] Use APInt::getBitsSetFrom instead of inverting the result of getLowBitsSet. NFC 

llvm-svn: 300265
This commit is contained in:
Craig Topper 2017-04-13 21:49:48 +00:00
parent cf681266e6
commit e7563f8dda
1 changed files with 2 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
View File

@ -3810,16 +3810,14 @@ static APInt getDemandedBitsLHSMask(ICmpInst &I, unsigned BitWidth,
// greater than the RHS must differ in a bit higher than these due to carry.
case ICmpInst::ICMP_UGT: {
unsigned trailingOnes = RHS.countTrailingOnes();
APInt lowBitsSet = APInt::getLowBitsSet(BitWidth, trailingOnes);
return ~lowBitsSet;
return APInt::getBitsSetFrom(BitWidth, trailingOnes);
}
// Similarly, for a ULT comparison, we don't care about the trailing zeros.
// Any value less than the RHS must differ in a higher bit because of carries.
case ICmpInst::ICMP_ULT: {
unsigned trailingZeros = RHS.countTrailingZeros();
APInt lowBitsSet = APInt::getLowBitsSet(BitWidth, trailingZeros);
return ~lowBitsSet;
return APInt::getBitsSetFrom(BitWidth, trailingZeros);
}
default: