diff options
Diffstat (limited to 'llvm/lib/Analysis')
| -rw-r--r-- | llvm/lib/Analysis/InstructionSimplify.cpp | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index bd42af15da3..1054c7935b5 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -1964,7 +1964,15 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, APInt Val = CI2->getValue().abs(); if (!Val.isMinValue()) { Lower = IntMin.sdiv(Val); - Upper = IntMax.sdiv(Val) + 1; + APInt Rem; + APInt::sdivrem(IntMax, Val, Upper, Rem); + // We may need to round the result of the INT_MAX / CI2 calculation up + // if we see that the division was not exact. + if (Rem.isMinValue()) + Upper = Upper + 1; + else + Upper = Upper + 2; + assert(Upper != Lower && "Upper part of range has wrapped!"); } } else if (match(LHS, m_LShr(m_Value(), m_ConstantInt(CI2)))) { // 'lshr x, CI2' produces [0, UINT_MAX >> CI2]. |
