1 files changed, 207 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Analysis/MemoryBuiltins.cpp b/contrib/llvm/lib/Analysis/MemoryBuiltins.cpp
new file mode 100644
index 0000000..89f9743
--- /dev/null
+++ b/contrib/llvm/lib/Analysis/MemoryBuiltins.cpp
@@ -0,0 +1,207 @@
+//===------ MemoryBuiltins.cpp - Identify calls to memory builtins --------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This family of functions identifies calls to builtin functions that allocate
+// or free memory.  
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/MemoryBuiltins.h"
+#include "llvm/Constants.h"
+#include "llvm/Instructions.h"
+#include "llvm/Module.h"
+#include "llvm/Analysis/ValueTracking.h"
+#include "llvm/Target/TargetData.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+//  malloc Call Utility Functions.
+//
+
+/// isMalloc - Returns true if the value is either a malloc call or a
+/// bitcast of the result of a malloc call.
+bool llvm::isMalloc(const Value *I) {
+  return extractMallocCall(I) || extractMallocCallFromBitCast(I);
+}
+
+static bool isMallocCall(const CallInst *CI) {
+  if (!CI)
+    return false;
+
+  Function *Callee = CI->getCalledFunction();
+  if (Callee == 0 || !Callee->isDeclaration() || Callee->getName() != "malloc")
+    return false;
+
+  // Check malloc prototype.
+  // FIXME: workaround for PR5130, this will be obsolete when a nobuiltin 
+  // attribute will exist.
+  const FunctionType *FTy = Callee->getFunctionType();
+  if (FTy->getNumParams() != 1)
+    return false;
+  if (IntegerType *ITy = dyn_cast<IntegerType>(FTy->param_begin()->get())) {
+    if (ITy->getBitWidth() != 32 && ITy->getBitWidth() != 64)
+      return false;
+    return true;
+  }
+
+  return false;
+}
+
+/// extractMallocCall - Returns the corresponding CallInst if the instruction
+/// is a malloc call.  Since CallInst::CreateMalloc() only creates calls, we
+/// ignore InvokeInst here.
+const CallInst *llvm::extractMallocCall(const Value *I) {
+  const CallInst *CI = dyn_cast<CallInst>(I);
+  return (isMallocCall(CI)) ? CI : NULL;
+}
+
+CallInst *llvm::extractMallocCall(Value *I) {
+  CallInst *CI = dyn_cast<CallInst>(I);
+  return (isMallocCall(CI)) ? CI : NULL;
+}
+
+static bool isBitCastOfMallocCall(const BitCastInst *BCI) {
+  if (!BCI)
+    return false;
+    
+  return isMallocCall(dyn_cast<CallInst>(BCI->getOperand(0)));
+}
+
+/// extractMallocCallFromBitCast - Returns the corresponding CallInst if the
+/// instruction is a bitcast of the result of a malloc call.
+CallInst *llvm::extractMallocCallFromBitCast(Value *I) {
+  BitCastInst *BCI = dyn_cast<BitCastInst>(I);
+  return (isBitCastOfMallocCall(BCI)) ? cast<CallInst>(BCI->getOperand(0))
+                                      : NULL;
+}
+
+const CallInst *llvm::extractMallocCallFromBitCast(const Value *I) {
+  const BitCastInst *BCI = dyn_cast<BitCastInst>(I);
+  return (isBitCastOfMallocCall(BCI)) ? cast<CallInst>(BCI->getOperand(0))
+                                      : NULL;
+}
+
+static Value *computeArraySize(const CallInst *CI, const TargetData *TD,
+                               bool LookThroughSExt = false) {
+  if (!CI)
+    return NULL;
+
+  // The size of the malloc's result type must be known to determine array size.
+  const Type *T = getMallocAllocatedType(CI);
+  if (!T || !T->isSized() || !TD)
+    return NULL;
+
+  unsigned ElementSize = TD->getTypeAllocSize(T);
+  if (const StructType *ST = dyn_cast<StructType>(T))
+    ElementSize = TD->getStructLayout(ST)->getSizeInBytes();
+
+  // If malloc calls' arg can be determined to be a multiple of ElementSize,
+  // return the multiple.  Otherwise, return NULL.
+  Value *MallocArg = CI->getOperand(1);
+  Value *Multiple = NULL;
+  if (ComputeMultiple(MallocArg, ElementSize, Multiple,
+                      LookThroughSExt))
+    return Multiple;
+
+  return NULL;
+}
+
+/// isArrayMalloc - Returns the corresponding CallInst if the instruction 
+/// is a call to malloc whose array size can be determined and the array size
+/// is not constant 1.  Otherwise, return NULL.
+const CallInst *llvm::isArrayMalloc(const Value *I, const TargetData *TD) {
+  const CallInst *CI = extractMallocCall(I);
+  Value *ArraySize = computeArraySize(CI, TD);
+
+  if (ArraySize &&
+      ArraySize != ConstantInt::get(CI->getOperand(1)->getType(), 1))
+    return CI;
+
+  // CI is a non-array malloc or we can't figure out that it is an array malloc.
+  return NULL;
+}
+
+/// getMallocType - Returns the PointerType resulting from the malloc call.
+/// The PointerType depends on the number of bitcast uses of the malloc call:
+///   0: PointerType is the calls' return type.
+///   1: PointerType is the bitcast's result type.
+///  >1: Unique PointerType cannot be determined, return NULL.
+const PointerType *llvm::getMallocType(const CallInst *CI) {
+  assert(isMalloc(CI) && "getMallocType and not malloc call");
+  
+  const PointerType *MallocType = NULL;
+  unsigned NumOfBitCastUses = 0;
+
+  // Determine if CallInst has a bitcast use.
+  for (Value::const_use_iterator UI = CI->use_begin(), E = CI->use_end();
+       UI != E; )
+    if (const BitCastInst *BCI = dyn_cast<BitCastInst>(*UI++)) {
+      MallocType = cast<PointerType>(BCI->getDestTy());
+      NumOfBitCastUses++;
+    }
+
+  // Malloc call has 1 bitcast use, so type is the bitcast's destination type.
+  if (NumOfBitCastUses == 1)
+    return MallocType;
+
+  // Malloc call was not bitcast, so type is the malloc function's return type.
+  if (NumOfBitCastUses == 0)
+    return cast<PointerType>(CI->getType());
+
+  // Type could not be determined.
+  return NULL;
+}
+
+/// getMallocAllocatedType - Returns the Type allocated by malloc call.
+/// The Type depends on the number of bitcast uses of the malloc call:
+///   0: PointerType is the malloc calls' return type.
+///   1: PointerType is the bitcast's result type.
+///  >1: Unique PointerType cannot be determined, return NULL.
+const Type *llvm::getMallocAllocatedType(const CallInst *CI) {
+  const PointerType *PT = getMallocType(CI);
+  return PT ? PT->getElementType() : NULL;
+}
+
+/// getMallocArraySize - Returns the array size of a malloc call.  If the 
+/// argument passed to malloc is a multiple of the size of the malloced type,
+/// then return that multiple.  For non-array mallocs, the multiple is
+/// constant 1.  Otherwise, return NULL for mallocs whose array size cannot be
+/// determined.
+Value *llvm::getMallocArraySize(CallInst *CI, const TargetData *TD,
+                                bool LookThroughSExt) {
+  assert(isMalloc(CI) && "getMallocArraySize and not malloc call");
+  return computeArraySize(CI, TD, LookThroughSExt);
+}
+
+//===----------------------------------------------------------------------===//
+//  free Call Utility Functions.
+//
+
+/// isFreeCall - Returns true if the value is a call to the builtin free()
+bool llvm::isFreeCall(const Value *I) {
+  const CallInst *CI = dyn_cast<CallInst>(I);
+  if (!CI)
+    return false;
+  Function *Callee = CI->getCalledFunction();
+  if (Callee == 0 || !Callee->isDeclaration() || Callee->getName() != "free")
+    return false;
+
+  // Check free prototype.
+  // FIXME: workaround for PR5130, this will be obsolete when a nobuiltin 
+  // attribute will exist.
+  const FunctionType *FTy = Callee->getFunctionType();
+  if (!FTy->getReturnType()->isVoidTy())
+    return false;
+  if (FTy->getNumParams() != 1)
+    return false;
+  if (FTy->param_begin()->get() != Type::getInt8PtrTy(Callee->getContext()))
+    return false;
+
+  return true;
+}