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-rw-r--r--lib/Transforms/Utils/LowerAllocations.cpp103
1 files changed, 10 insertions, 93 deletions
diff --git a/lib/Transforms/Utils/LowerAllocations.cpp b/lib/Transforms/Utils/LowerAllocations.cpp
index ff3c29f11a..e5bf88fc00 100644
--- a/lib/Transforms/Utils/LowerAllocations.cpp
+++ b/lib/Transforms/Utils/LowerAllocations.cpp
@@ -1,16 +1,14 @@
-//===- ChangeAllocations.cpp - Modify %malloc & %free calls -----------------=//
+//===- LowerAllocations.cpp - Reduce malloc & free insts to calls ---------===//
//
-// This file defines two passes that convert malloc and free instructions to
-// calls to and from %malloc & %free function calls. The LowerAllocations
-// transformation is a target dependant tranformation because it depends on the
-// size of data types and alignment constraints.
+// The LowerAllocations transformation is a target dependant tranformation
+// because it depends on the size of data types and alignment constraints.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/ChangeAllocations.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Module.h"
#include "llvm/Function.h"
+#include "llvm/BasicBlock.h"
#include "llvm/DerivedTypes.h"
#include "llvm/iMemory.h"
#include "llvm/iOther.h"
@@ -47,29 +45,13 @@ public:
bool runOnBasicBlock(BasicBlock *BB);
};
-// RaiseAllocations - Turn %malloc and %free calls into the appropriate
-// instruction.
-//
-class RaiseAllocations : public BasicBlockPass {
- Function *MallocFunc; // Functions in the module we are processing
- Function *FreeFunc; // Initialized by doPassInitializationVirt
-public:
- inline RaiseAllocations() : MallocFunc(0), FreeFunc(0) {}
-
- const char *getPassName() const { return "Raise Allocations"; }
-
- // doPassInitialization - For the raise allocations pass, this finds a
- // declaration for malloc and free if they exist.
- //
- bool doInitialization(Module *M);
+}
- // runOnBasicBlock - This method does the actual work of converting
- // instructions over, assuming that the pass has already been initialized.
- //
- bool runOnBasicBlock(BasicBlock *BB);
-};
+// createLowerAllocationsPass - Interface to this file...
+Pass *createLowerAllocationsPass(const TargetData &TD) {
+ return new LowerAllocations(TD);
+}
-} // end anonymous namespace
// doInitialization - For the lower allocations pass, this ensures that a
// module contains a declaration for a malloc and a free function.
@@ -88,7 +70,7 @@ bool LowerAllocations::doInitialization(Module *M) {
MallocFunc = M->getOrInsertFunction("malloc", MallocType);
FreeFunc = M->getOrInsertFunction("free" , FreeType);
- return false;
+ return true;
}
// runOnBasicBlock - This method does the actual work of converting
@@ -155,68 +137,3 @@ bool LowerAllocations::runOnBasicBlock(BasicBlock *BB) {
return Changed;
}
-
-bool RaiseAllocations::doInitialization(Module *M) {
- // If the module has a symbol table, they might be referring to the malloc
- // and free functions. If this is the case, grab the method pointers that
- // the module is using.
- //
- // Lookup %malloc and %free in the symbol table, for later use. If they
- // don't exist, or are not external, we do not worry about converting calls
- // to that function into the appropriate instruction.
- //
- const FunctionType *MallocType = // Get the type for malloc
- FunctionType::get(PointerType::get(Type::SByteTy),
- vector<const Type*>(1, Type::UIntTy), false);
-
- const FunctionType *FreeType = // Get the type for free
- FunctionType::get(Type::VoidTy,
- vector<const Type*>(1, PointerType::get(Type::SByteTy)),
- false);
-
- MallocFunc = M->getFunction("malloc", MallocType);
- FreeFunc = M->getFunction("free" , FreeType);
-
- // Don't mess with locally defined versions of these functions...
- if (MallocFunc && !MallocFunc->isExternal()) MallocFunc = 0;
- if (FreeFunc && !FreeFunc->isExternal()) FreeFunc = 0;
- return false;
-}
-
-// doOneCleanupPass - Do one pass over the input method, fixing stuff up.
-//
-bool RaiseAllocations::runOnBasicBlock(BasicBlock *BB) {
- bool Changed = false;
- BasicBlock::InstListType &BIL = BB->getInstList();
-
- for (BasicBlock::iterator BI = BB->begin(); BI != BB->end();) {
- Instruction *I = *BI;
-
- if (CallInst *CI = dyn_cast<CallInst>(I)) {
- if (CI->getCalledValue() == MallocFunc) { // Replace call to malloc?
- const Type *PtrSByte = PointerType::get(Type::SByteTy);
- MallocInst *MallocI = new MallocInst(PtrSByte, CI->getOperand(1),
- CI->getName());
- CI->setName("");
- ReplaceInstWithInst(BIL, BI, MallocI);
- Changed = true;
- continue; // Skip the ++BI
- } else if (CI->getCalledValue() == FreeFunc) { // Replace call to free?
- ReplaceInstWithInst(BIL, BI, new FreeInst(CI->getOperand(1)));
- Changed = true;
- continue; // Skip the ++BI
- }
- }
-
- ++BI;
- }
-
- return Changed;
-}
-
-Pass *createLowerAllocationsPass(const TargetData &TD) {
- return new LowerAllocations(TD);
-}
-Pass *createRaiseAllocationsPass() {
- return new RaiseAllocations();
-}