6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-02-21 21:29:41 +00:00
Code Issues Projects Releases Wiki Activity

Avoid allocating a value of zero in a register if the initial formula

Browse Source 
inputs happen to negate each other.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100828 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2010-04-08 23:36:27 +00:00
parent dd98c4d185
commit e60bb15982
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
lib/Transforms/Scalar/LoopStrengthReduce.cpp
View File

@ -262,11 +262,15 @@ void Formula::InitialMatch(const SCEV *S, Loop *L,
SmallVector<const SCEV *, 4> Bad;
DoInitialMatch(S, L, Good, Bad, SE, DT);
if (!Good.empty()) {
BaseRegs.push_back(SE.getAddExpr(Good));
const SCEV *Sum = SE.getAddExpr(Good);
if (!Sum->isZero())
BaseRegs.push_back(Sum);
AM.HasBaseReg = true;
}
if (!Bad.empty()) {
BaseRegs.push_back(SE.getAddExpr(Bad));
const SCEV *Sum = SE.getAddExpr(Bad);
if (!Sum->isZero())
BaseRegs.push_back(Sum);
AM.HasBaseReg = true;
}
}