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Remove dead code 

llvm-svn: 4952
This commit is contained in:
Chris Lattner 2002-12-07 18:42:13 +00:00
parent 55dfb8230e
commit 688ac5b723
1 changed files with 0 additions and 32 deletions
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32
llvm/lib/Transforms/Scalar/GCSE.cpp
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@ -25,9 +25,6 @@ namespace {
class GCSE : public FunctionPass {
std::set<Instruction*> WorkList;
DominatorSet *DomSetInfo;
#if 0
ImmediateDominators *ImmDominator;
#endif
ValueNumbering *VN;
public:
virtual bool runOnFunction(Function &F);
@ -61,9 +58,6 @@ bool GCSE::runOnFunction(Function &F) {
// Get pointers to the analysis results that we will be using...
DomSetInfo = &getAnalysis<DominatorSet>();
#if 0
ImmDominator = &getAnalysis<ImmediateDominators>();
#endif
VN = &getAnalysis<ValueNumbering>();
// Step #1: Add all instructions in the function to the worklist for
@ -254,32 +248,6 @@ Instruction *GCSE::EliminateCSE(Instruction *I, Instruction *Other) {
// PRE than GCSE.
//
return 0;
#if 0
// Handle the most general case now. In this case, neither I dom Other nor
// Other dom I. Because we are in SSA form, we are guaranteed that the
// operands of the two instructions both dominate the uses, so we _know_
// that there must exist a block that dominates both instructions (if the
// operands of the instructions are globals or constants, worst case we
// would get the entry node of the function). Search for this block now.
//
// Search up the immediate dominator chain of BB1 for the shared dominator
BasicBlock *SharedDom = (*ImmDominator)[BB1];
while (!DomSetInfo->dominates(SharedDom, BB2))
SharedDom = (*ImmDominator)[SharedDom];
// At this point, shared dom must dominate BOTH BB1 and BB2...
assert(SharedDom && DomSetInfo->dominates(SharedDom, BB1) &&
DomSetInfo->dominates(SharedDom, BB2) && "Dominators broken!");
// Rip 'I' out of BB1, and move it to the end of SharedDom.
BB1->getInstList().remove(I);
SharedDom->getInstList().insert(--SharedDom->end(), I);
// Eliminate 'Other' now.
ReplaceInstWithInst(I, Other);
#endif
}
if (isa<LoadInst>(Ret))