mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-19 17:33:29 +00:00
7e70829632
For details, See: docs/2002-06-25-MegaPatchInfo.txt git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2779 91177308-0d34-0410-b5e6-96231b3b80d8
106 lines
3.6 KiB
C++
106 lines
3.6 KiB
C++
//===----------------------------------------------------------------------===//
|
|
// LLVM extract Utility
|
|
//
|
|
// This utility changes the input module to only contain a single function,
|
|
// which is primarily used for debugging transformations.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Module.h"
|
|
#include "llvm/PassManager.h"
|
|
#include "llvm/Bytecode/Reader.h"
|
|
#include "llvm/Bytecode/WriteBytecodePass.h"
|
|
#include "llvm/GlobalVariable.h"
|
|
#include "llvm/Function.h"
|
|
#include "llvm/Transforms/IPO/GlobalDCE.h"
|
|
#include "llvm/Transforms/ConstantMerge.h"
|
|
#include "llvm/Transforms/CleanupGCCOutput.h"
|
|
#include "Support/CommandLine.h"
|
|
#include <memory>
|
|
|
|
static cl::String InputFilename("", "Specify input bytecode file", 0, "-");
|
|
static cl::String ExtractFunc("func", "Specify function to extract", 0, "main");
|
|
|
|
struct FunctionExtractorPass : public Pass {
|
|
const char *getPassName() const { return "Function Extractor"; }
|
|
|
|
bool run(Module &M) {
|
|
// Mark all global variables to be internal
|
|
for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
|
|
I->setInternalLinkage(true);
|
|
|
|
Function *Named = 0;
|
|
|
|
// Loop over all of the functions in the module, dropping all references in
|
|
// functions that are not the named function.
|
|
for (Module::iterator I = M.begin(), E = M.end(); I != E;)
|
|
// Check to see if this is the named function!
|
|
if (!Named && I->getName() == ExtractFunc) {
|
|
// Yes, it is. Keep track of it...
|
|
Named = I;
|
|
|
|
// Make sure it's globally accessable...
|
|
Named->setInternalLinkage(false);
|
|
|
|
// Remove the named function from the module.
|
|
M.getFunctionList().remove(I);
|
|
} else {
|
|
// Nope it's not the named function, delete the body of the function
|
|
I->dropAllReferences();
|
|
++I;
|
|
}
|
|
|
|
// All of the functions that still have uses now must be used by global
|
|
// variables or the named function. Loop through them and create a new,
|
|
// external function for the used ones... making all uses point to the new
|
|
// functions.
|
|
std::vector<Function*> NewFunctions;
|
|
|
|
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
|
|
if (!I->use_empty()) {
|
|
Function *New = new Function(I->getFunctionType(), false, I->getName());
|
|
I->replaceAllUsesWith(New);
|
|
NewFunctions.push_back(New);
|
|
}
|
|
|
|
// Now the module only has unused functions with their references dropped.
|
|
// Delete them all now!
|
|
M.getFunctionList().clear();
|
|
|
|
// Re-insert the named function...
|
|
if (Named)
|
|
M.getFunctionList().push_back(Named);
|
|
else
|
|
std::cerr << "Warning: Function '" << ExtractFunc << "' not found!\n";
|
|
|
|
// Insert all of the function stubs...
|
|
M.getFunctionList().insert(M.end(), NewFunctions.begin(),
|
|
NewFunctions.end());
|
|
return true;
|
|
}
|
|
};
|
|
|
|
|
|
int main(int argc, char **argv) {
|
|
cl::ParseCommandLineOptions(argc, argv, " llvm extractor\n");
|
|
|
|
std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename));
|
|
if (M.get() == 0) {
|
|
std::cerr << "bytecode didn't read correctly.\n";
|
|
return 1;
|
|
}
|
|
|
|
// In addition to just parsing the input from GCC, we also want to spiff it up
|
|
// a little bit. Do this now.
|
|
//
|
|
PassManager Passes;
|
|
Passes.add(new FunctionExtractorPass());
|
|
Passes.add(createGlobalDCEPass()); // Delete unreachable globals
|
|
Passes.add(createConstantMergePass()); // Merge dup global constants
|
|
Passes.add(createCleanupGCCOutputPass()); // Fix gccisms
|
|
Passes.add(new WriteBytecodePass(&std::cout)); // Write bytecode to file...
|
|
|
|
Passes.run(*M.get());
|
|
return 0;
|
|
}
|