Make bugpoint *much* more powerful, giving it the capability to delete instructions
out of a large function to reduce it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5408 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/bugpoint/ExtractFunction.cpp b/tools/bugpoint/ExtractFunction.cpp
index 76b2258..9b5440c 100644
--- a/tools/bugpoint/ExtractFunction.cpp
+++ b/tools/bugpoint/ExtractFunction.cpp
@@ -9,7 +9,10 @@
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/Transforms/IPO.h"
+#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/Cloning.h"
+#include "llvm/Type.h"
+#include "llvm/Constant.h"
/// extractFunctionFromModule - This method is used to extract the specified
/// (non-external) function from the current program, slim down the module, and
@@ -19,16 +22,62 @@
Module *Result = CloneModule(Program);
// Translate from the old module to the new copied module...
- F = Result->getFunction(F->getName(), F->getFunctionType());
+ Module::iterator RFI = Result->begin(); // Get iterator to corresponding fn
+ std::advance(RFI, std::distance(Program->begin(), Module::iterator(F)));
// 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(createFunctionExtractionPass(F)); // Extract the function
+ Passes.add(createFunctionExtractionPass(RFI)); // Extract the function
Passes.add(createGlobalDCEPass()); // Delete unreachable globals
Passes.add(createFunctionResolvingPass()); // Delete prototypes
Passes.add(createDeadTypeEliminationPass()); // Remove dead types...
Passes.run(*Result);
return Result;
}
+
+
+/// deleteInstructionFromProgram - This method clones the current Program and
+/// deletes the specified instruction from the cloned module. It then runs a
+/// series of cleanup passes (ADCE and SimplifyCFG) to eliminate any code which
+/// depends on the value. The modified module is then returned.
+///
+Module *BugDriver::deleteInstructionFromProgram(Instruction *I,
+ unsigned Simplification) const {
+ Module *Result = CloneModule(Program);
+
+ BasicBlock *PBB = I->getParent();
+ Function *PF = PBB->getParent();
+
+ Module::iterator RFI = Result->begin(); // Get iterator to corresponding fn
+ std::advance(RFI, std::distance(Program->begin(), Module::iterator(PF)));
+
+ Function::iterator RBI = RFI->begin(); // Get iterator to corresponding BB
+ std::advance(RBI, std::distance(PF->begin(), Function::iterator(PBB)));
+
+ BasicBlock::iterator RI = RBI->begin(); // Get iterator to corresponding inst
+ std::advance(RI, std::distance(PBB->begin(), BasicBlock::iterator(I)));
+ I = RI; // Got the corresponding instruction!
+
+ // If this instruction produces a value, replace any users with null values
+ if (I->getType() != Type::VoidTy)
+ I->replaceAllUsesWith(Constant::getNullValue(I->getType()));
+
+ // Remove the instruction from the program.
+ I->getParent()->getInstList().erase(I);
+
+ // In addition to just parsing the input from GCC, we also want to spiff it up
+ // a little bit. Do this now.
+ //
+ PassManager Passes;
+ if (Simplification > 2)
+ Passes.add(createAggressiveDCEPass()); // Remove dead code...
+ //Passes.add(createInstructionCombiningPass());
+ if (Simplification > 1)
+ Passes.add(createDeadCodeEliminationPass());
+ if (Simplification)
+ Passes.add(createCFGSimplificationPass()); // Delete dead control flow
+ Passes.run(*Result);
+ return Result;
+}