6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-15 04:30:12 +00:00
Code Issues Projects Releases Wiki Activity

Take advantage of undefined behavior if the source program tries to GEP

Browse Source 
beyond the end of an alloca to make FastDSE faster and more aggressive.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39945 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2007-07-16 23:34:39 +00:00
parent 162c518286
commit ce17b1c1f8
1 changed files with 4 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
lib/Transforms/Scalar/FastDSE.cpp
View File

@ -61,17 +61,10 @@ namespace {
// See through pointer-to-pointer bitcasts
while (isa<BitCastInst>(v) || isa<GetElementPtrInst>(v))
if (BitCastInst* C = dyn_cast<BitCastInst>(v)) {
if (isa<PointerType>(C->getSrcTy()))
v = C->getOperand(0);
else
break;
} else if (GetElementPtrInst* G = dyn_cast<GetElementPtrInst>(v)) {
if (G->hasAllZeroIndices())
v = G->getOperand(0);
else
break;
}
if (BitCastInst* C = dyn_cast<BitCastInst>(v))
v = C->getOperand(0);
else if (GetElementPtrInst* G = dyn_cast<GetElementPtrInst>(v))
v = G->getOperand(0);
}
// getAnalysisUsage - We require post dominance frontiers (aka Control