6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-01-14 00:32:55 +00:00
Code Issues Projects Releases Wiki Activity

Start generating arbitrary precision integer SCEVs. This removes the temporary

Browse Source 
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
This commit is contained in:
Nick Lewycky 2009-01-25 08:16:27 +00:00
parent 67e1f49a50
commit 237d873439
1 changed files with 1 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
lib/Analysis/ScalarEvolution.cpp
View File

@ -585,17 +585,7 @@ static SCEVHandle BinomialCoefficient(SCEVHandle It, unsigned K,
} }
// We need at least W + T bits for the multiplication step // We need at least W + T bits for the multiplication step
// FIXME: A temporary hack; we round up the bitwidths unsigned CalculationBits = W + T;
// 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();
// Calcuate 2^T, at width T+W. // Calcuate 2^T, at width T+W.
APInt DivFactor = APInt(CalculationBits, 1).shl(T); APInt DivFactor = APInt(CalculationBits, 1).shl(T);