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-rw-r--r--contrib/llvm/lib/CodeGen/StackProtector.cpp69
1 files changed, 44 insertions, 25 deletions
diff --git a/contrib/llvm/lib/CodeGen/StackProtector.cpp b/contrib/llvm/lib/CodeGen/StackProtector.cpp
index f1eab1f..31e9ec0 100644
--- a/contrib/llvm/lib/CodeGen/StackProtector.cpp
+++ b/contrib/llvm/lib/CodeGen/StackProtector.cpp
@@ -26,18 +26,12 @@
#include "llvm/Module.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
-#include "llvm/Target/TargetData.h"
+#include "llvm/DataLayout.h"
#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/Triple.h"
using namespace llvm;
-// SSPBufferSize - The lower bound for a buffer to be considered for stack
-// smashing protection.
-static cl::opt<unsigned>
-SSPBufferSize("stack-protector-buffer-size", cl::init(8),
- cl::desc("Lower bound for a buffer to be considered for "
- "stack protection"));
-
namespace {
class StackProtector : public FunctionPass {
/// TLI - Keep a pointer of a TargetLowering to consult for determining
@@ -61,6 +55,11 @@ namespace {
/// check fails.
BasicBlock *CreateFailBB();
+ /// ContainsProtectableArray - Check whether the type either is an array or
+ /// contains an array of sufficient size so that we need stack protectors
+ /// for it.
+ bool ContainsProtectableArray(Type *Ty, bool InStruct = false) const;
+
/// RequiresStackProtector - Check whether or not this function needs a
/// stack protector based upon the stack protector level.
bool RequiresStackProtector() const;
@@ -100,21 +99,50 @@ bool StackProtector::runOnFunction(Function &Fn) {
return InsertStackProtectors();
}
+/// ContainsProtectableArray - Check whether the type either is an array or
+/// contains a char array of sufficient size so that we need stack protectors
+/// for it.
+bool StackProtector::ContainsProtectableArray(Type *Ty, bool InStruct) const {
+ if (!Ty) return false;
+ if (ArrayType *AT = dyn_cast<ArrayType>(Ty)) {
+ const TargetMachine &TM = TLI->getTargetMachine();
+ if (!AT->getElementType()->isIntegerTy(8)) {
+ Triple Trip(TM.getTargetTriple());
+
+ // If we're on a non-Darwin platform or we're inside of a structure, don't
+ // add stack protectors unless the array is a character array.
+ if (InStruct || !Trip.isOSDarwin())
+ return false;
+ }
+
+ // If an array has more than SSPBufferSize bytes of allocated space, then we
+ // emit stack protectors.
+ if (TM.Options.SSPBufferSize <= TLI->getDataLayout()->getTypeAllocSize(AT))
+ return true;
+ }
+
+ const StructType *ST = dyn_cast<StructType>(Ty);
+ if (!ST) return false;
+
+ for (StructType::element_iterator I = ST->element_begin(),
+ E = ST->element_end(); I != E; ++I)
+ if (ContainsProtectableArray(*I, true))
+ return true;
+
+ return false;
+}
+
/// RequiresStackProtector - Check whether or not this function needs a stack
/// protector based upon the stack protector level. The heuristic we use is to
/// add a guard variable to functions that call alloca, and functions with
/// buffers larger than SSPBufferSize bytes.
bool StackProtector::RequiresStackProtector() const {
- if (F->hasFnAttr(Attribute::StackProtectReq))
+ if (F->getFnAttributes().hasAttribute(Attributes::StackProtectReq))
return true;
- if (!F->hasFnAttr(Attribute::StackProtect))
+ if (!F->getFnAttributes().hasAttribute(Attributes::StackProtect))
return false;
- const TargetData *TD = TLI->getTargetData();
- const TargetMachine &TM = TLI->getTargetMachine();
- Triple Trip(TM.getTargetTriple());
-
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
BasicBlock *BB = I;
@@ -126,17 +154,8 @@ bool StackProtector::RequiresStackProtector() const {
// protectors.
return true;
- if (ArrayType *AT = dyn_cast<ArrayType>(AI->getAllocatedType())) {
- // If we're on a non-Darwin platform, don't add stack protectors
- // unless the array is a character array.
- if (!Trip.isOSDarwin() && !AT->getElementType()->isIntegerTy(8))
- continue;
-
- // If an array has more than SSPBufferSize bytes of allocated space,
- // then we emit stack protectors.
- if (SSPBufferSize <= TD->getTypeAllocSize(AT))
- return true;
- }
+ if (ContainsProtectableArray(AI->getAllocatedType()))
+ return true;
}
}
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