From 237d873439ed170e0d9608920d45d11d05bb5e5f Mon Sep 17 00:00:00 2001 From: Nick Lewycky Date: Sun, 25 Jan 2009 08:16:27 +0000 Subject: [PATCH] Start generating arbitrary precision integer SCEVs. This removes the temporary code that rounded up and capped the size. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62958 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Analysis/ScalarEvolution.cpp | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-) diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp index ca16a755dca..c05ba8d0ef2 100644 --- a/lib/Analysis/ScalarEvolution.cpp +++ b/lib/Analysis/ScalarEvolution.cpp @@ -585,17 +585,7 @@ static SCEVHandle BinomialCoefficient(SCEVHandle It, unsigned K, } // We need at least W + T bits for the multiplication step - // FIXME: A temporary hack; we round up the bitwidths - // to the nearest power of 2 to be nice to the code generator. - unsigned CalculationBits = 1U << Log2_32_Ceil(W + T); - // FIXME: Temporary hack to avoid generating integers that are too wide. - // Although, it's not completely clear how to determine how much - // widening is safe; for example, on X86, we can't really widen - // beyond 64 because we need to be able to do multiplication - // that's CalculationBits wide, but on X86-64, we can safely widen up to - // 128 bits. - if (CalculationBits > 64) - return new SCEVCouldNotCompute(); + unsigned CalculationBits = W + T; // Calcuate 2^T, at width T+W. APInt DivFactor = APInt(CalculationBits, 1).shl(T);