llvm-6502/lib/Transforms/Scalar/SymbolStripping.cpp
Chris Lattner 6e6026b465 - Eliminated the deferred symbol table stuff in Module & Function, it really
wasn't an optimization and it was causing lots of bugs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4779 91177308-0d34-0410-b5e6-96231b3b80d8
2002-11-20 18:36:02 +00:00

70 lines
2.2 KiB
C++

//===- SymbolStripping.cpp - Strip symbols for functions and modules ------===//
//
// This file implements stripping symbols out of symbol tables.
//
// Specifically, this allows you to strip all of the symbols out of:
// * A function
// * All functions in a module
// * All symbols in a module (all function symbols + all module scope symbols)
//
// Notice that:
// * This pass makes code much less readable, so it should only be used in
// situations where the 'strip' utility would be used (such as reducing
// code size, and making it harder to reverse engineer code).
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/Module.h"
#include "llvm/SymbolTable.h"
#include "llvm/Pass.h"
static bool StripSymbolTable(SymbolTable &SymTab) {
bool RemovedSymbol = false;
for (SymbolTable::iterator I = SymTab.begin(); I != SymTab.end(); ++I) {
std::map<const std::string, Value *> &Plane = I->second;
SymbolTable::type_iterator B;
while ((B = Plane.begin()) != Plane.end()) { // Found nonempty type plane!
Value *V = B->second;
if (isa<Constant>(V) || isa<Type>(V))
SymTab.type_remove(B);
else
V->setName("", &SymTab); // Set name to "", removing from symbol table!
RemovedSymbol = true;
assert(Plane.begin() != B && "Symbol not removed from table!");
}
}
return RemovedSymbol;
}
namespace {
struct SymbolStripping : public FunctionPass {
virtual bool runOnFunction(Function &F) {
return StripSymbolTable(F.getSymbolTable());
}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
}
};
RegisterOpt<SymbolStripping> X("strip", "Strip symbols from functions");
struct FullSymbolStripping : public SymbolStripping {
virtual bool doInitialization(Module &M) {
return StripSymbolTable(M.getSymbolTable());
}
};
RegisterOpt<FullSymbolStripping> Y("mstrip",
"Strip symbols from module and functions");
}
Pass *createSymbolStrippingPass() {
return new SymbolStripping();
}
Pass *createFullSymbolStrippingPass() {
return new FullSymbolStripping();
}