Strip invalid TBAA when reading bitcode
This ensures backward compatibility on bitcode loading.
Differential Revision: https://reviews.llvm.org/D27839
llvm-svn: 289977
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 36f3239..ad4d9ce 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -48,6 +48,7 @@
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/GVMaterializer.h"
#include "llvm/IR/InlineAsm.h"
+#include "llvm/IR/InstIterator.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
@@ -60,6 +61,7 @@
#include "llvm/IR/TrackingMDRef.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/ValueHandle.h"
+#include "llvm/IR/Verifier.h"
#include "llvm/Support/AtomicOrdering.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
@@ -148,6 +150,16 @@
return false;
}
+// Strip all the TBAA attachment for the module.
+void stripTBAA(Module *M) {
+ for (auto &F : *M) {
+ if (F.isMaterializable())
+ continue;
+ for (auto &I : instructions(F))
+ I.setMetadata(LLVMContext::MD_tbaa, nullptr);
+ }
+}
+
/// Read the "IDENTIFICATION_BLOCK_ID" block, do some basic enforcement on the
/// "epoch" encoded in the bitcode, and return the producer name if any.
Expected<std::string> readIdentificationBlock(BitstreamCursor &Stream) {
@@ -460,6 +472,7 @@
bool WillMaterializeAllForwardRefs = false;
bool StripDebugInfo = false;
+ TBAAVerifier TBAAVerifyHelper;
std::vector<std::string> BundleTags;
@@ -4449,6 +4462,17 @@
if (DISubprogram *SP = MDLoader->lookupSubprogramForFunction(F))
F->setSubprogram(SP);
+ // Check if the TBAA Metadata are valid, otherwise we will need to strip them.
+ if (!MDLoader->isStrippingTBAA()) {
+ for (auto &I : instructions(F)) {
+ MDNode *TBAA = I.getMetadata(LLVMContext::MD_tbaa);
+ if (!TBAA || TBAAVerifyHelper.visitTBAAMetadata(I, TBAA))
+ continue;
+ MDLoader->setStripTBAA(true);
+ stripTBAA(F->getParent());
+ }
+ }
+
// Bring in any functions that this function forward-referenced via
// blockaddresses.
return materializeForwardReferencedFunctions();