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Diffstat (limited to 'llvm/lib/CodeGen/StackProtector.cpp')
-rw-r--r--llvm/lib/CodeGen/StackProtector.cpp62
1 files changed, 32 insertions, 30 deletions
diff --git a/llvm/lib/CodeGen/StackProtector.cpp b/llvm/lib/CodeGen/StackProtector.cpp
index cb12c7c..9bc0c1f 100644
--- a/llvm/lib/CodeGen/StackProtector.cpp
+++ b/llvm/lib/CodeGen/StackProtector.cpp
@@ -70,6 +70,32 @@ INITIALIZE_PASS_END(StackProtector, DEBUG_TYPE,
FunctionPass *llvm::createStackProtectorPass() { return new StackProtector(); }
+StackProtector::SSPLayoutKind
+StackProtector::getSSPLayout(const AllocaInst *AI) const {
+ return AI ? Layout.lookup(AI) : SSPLK_None;
+}
+
+void StackProtector::adjustForColoring(const AllocaInst *From,
+ const AllocaInst *To) {
+ // When coloring replaces one alloca with another, transfer the SSPLayoutKind
+ // tag from the remapped to the target alloca. The remapped alloca should
+ // have a size smaller than or equal to the replacement alloca.
+ SSPLayoutMap::iterator I = Layout.find(From);
+ if (I != Layout.end()) {
+ SSPLayoutKind Kind = I->second;
+ Layout.erase(I);
+
+ // Transfer the tag, but make sure that SSPLK_AddrOf does not overwrite
+ // SSPLK_SmallArray or SSPLK_LargeArray, and make sure that
+ // SSPLK_SmallArray does not overwrite SSPLK_LargeArray.
+ I = Layout.find(To);
+ if (I == Layout.end())
+ Layout.insert(std::make_pair(To, Kind));
+ else if (I->second != SSPLK_LargeArray && Kind != SSPLK_AddrOf)
+ I->second = Kind;
+ }
+}
+
void StackProtector::getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<TargetPassConfig>();
AU.addPreserved<DominatorTreeWrapperPass>();
@@ -263,21 +289,18 @@ bool StackProtector::RequiresStackProtector() {
if (CI->getLimitedValue(SSPBufferSize) >= SSPBufferSize) {
// A call to alloca with size >= SSPBufferSize requires
// stack protectors.
- Layout.insert(std::make_pair(AI,
- MachineFrameInfo::SSPLK_LargeArray));
+ Layout.insert(std::make_pair(AI, SSPLK_LargeArray));
ORE.emit(RemarkBuilder);
NeedsProtector = true;
} else if (Strong) {
// Require protectors for all alloca calls in strong mode.
- Layout.insert(std::make_pair(AI,
- MachineFrameInfo::SSPLK_SmallArray));
+ Layout.insert(std::make_pair(AI, SSPLK_SmallArray));
ORE.emit(RemarkBuilder);
NeedsProtector = true;
}
} else {
// A call to alloca with a variable size requires protectors.
- Layout.insert(std::make_pair(AI,
- MachineFrameInfo::SSPLK_LargeArray));
+ Layout.insert(std::make_pair(AI, SSPLK_LargeArray));
ORE.emit(RemarkBuilder);
NeedsProtector = true;
}
@@ -286,9 +309,8 @@ bool StackProtector::RequiresStackProtector() {
bool IsLarge = false;
if (ContainsProtectableArray(AI->getAllocatedType(), IsLarge, Strong)) {
- Layout.insert(std::make_pair(AI, IsLarge
- ? MachineFrameInfo::SSPLK_LargeArray
- : MachineFrameInfo::SSPLK_SmallArray));
+ Layout.insert(std::make_pair(AI, IsLarge ? SSPLK_LargeArray
+ : SSPLK_SmallArray));
ORE.emit([&]() {
return OptimizationRemark(DEBUG_TYPE, "StackProtectorBuffer", &I)
<< "Stack protection applied to function "
@@ -302,7 +324,7 @@ bool StackProtector::RequiresStackProtector() {
if (Strong && HasAddressTaken(AI)) {
++NumAddrTaken;
- Layout.insert(std::make_pair(AI, MachineFrameInfo::SSPLK_AddrOf));
+ Layout.insert(std::make_pair(AI, SSPLK_AddrOf));
ORE.emit([&]() {
return OptimizationRemark(DEBUG_TYPE, "StackProtectorAddressTaken",
&I)
@@ -512,23 +534,3 @@ BasicBlock *StackProtector::CreateFailBB() {
bool StackProtector::shouldEmitSDCheck(const BasicBlock &BB) const {
return HasPrologue && !HasIRCheck && dyn_cast<ReturnInst>(BB.getTerminator());
}
-
-void StackProtector::copyToMachineFrameInfo(MachineFrameInfo &MFI) const {
- if (Layout.empty())
- return;
-
- for (int I = 0, E = MFI.getObjectIndexEnd(); I != E; ++I) {
- if (MFI.isDeadObjectIndex(I))
- continue;
-
- const AllocaInst *AI = MFI.getObjectAllocation(I);
- if (!AI)
- continue;
-
- SSPLayoutMap::const_iterator LI = Layout.find(AI);
- if (LI == Layout.end())
- continue;
-
- MFI.setObjectSSPLayout(I, LI->second);
- }
-}