[ASan] Fix PR17867 - make sure ASan doesn't crash if use-after-scope and use-after-return are combined.

llvm-svn: 195014

1 files changed, 6 insertions, 6 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index d8c3f8eafb7..d731ec5499e 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -426,6 +426,7 @@ struct FunctionStackPoisoner : public InstVisitor<FunctionStackPoisoner> {
   // Stores a place and arguments of poisoning/unpoisoning call for alloca.
   struct AllocaPoisonCall {
     IntrinsicInst *InsBefore;
+    AllocaInst *AI;
     uint64_t Size;
     bool DoPoison;
   };
@@ -504,7 +505,7 @@ struct FunctionStackPoisoner : public InstVisitor<FunctionStackPoisoner> {
     AllocaInst *AI = findAllocaForValue(II.getArgOperand(1));
     if (!AI) return;
     bool DoPoison = (ID == Intrinsic::lifetime_end);
-    AllocaPoisonCall APC = {&II, SizeValue, DoPoison};
+    AllocaPoisonCall APC = {&II, AI, SizeValue, DoPoison};
     AllocaPoisonCallVec.push_back(APC);
   }
 
@@ -1523,11 +1524,10 @@ void FunctionStackPoisoner::poisonStack() {
   bool HavePoisonedAllocas = false;
   for (size_t i = 0, n = AllocaPoisonCallVec.size(); i < n; i++) {
     const AllocaPoisonCall &APC = AllocaPoisonCallVec[i];
-    IntrinsicInst *II = APC.InsBefore;
-    AllocaInst *AI = findAllocaForValue(II->getArgOperand(1));
-    assert(AI);
-    IRBuilder<> IRB(II);
-    poisonAlloca(AI, APC.Size, IRB, APC.DoPoison);
+    assert(APC.InsBefore);
+    assert(APC.AI);
+    IRBuilder<> IRB(APC.InsBefore);
+    poisonAlloca(APC.AI, APC.Size, IRB, APC.DoPoison);
     HavePoisonedAllocas |= APC.DoPoison;
   }