Revert "Teach the IR verifier to reject conflicting debug info for function arguments."

This reverts commit r295749 while investigating PR32042.

It looks like this check uncovered a problem in the frontend that
needs to be fixed before the check can be enabled again.

llvm-svn: 296005

1 files changed, 0 insertions, 38 deletions

diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 4dd18797a95..7d0bfd7270c 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -297,9 +297,6 @@ class Verifier : public InstVisitor<Verifier>, VerifierSupport {
   // constant expressions, we can arrive at a particular user many times.
   SmallPtrSet<const Value *, 32> GlobalValueVisited;
 
-  // Keeps track of duplicate function argument debug info.
-  SmallVector<const DILocalVariable *, 16> DebugFnArgs;
-
   TBAAVerifier TBAAVerifyHelper;
 
   void checkAtomicMemAccessSize(Type *Ty, const Instruction *I);
@@ -501,7 +498,6 @@ private:
   void verifySiblingFuncletUnwinds();
 
   void verifyFragmentExpression(const DbgInfoIntrinsic &I);
-  void verifyFnArgs(const DbgInfoIntrinsic &I);
 
   /// Module-level debug info verification...
   void verifyCompileUnits();
@@ -1950,8 +1946,6 @@ void Verifier::verifySiblingFuncletUnwinds() {
 // visitFunction - Verify that a function is ok.
 //
 void Verifier::visitFunction(const Function &F) {
-  DebugFnArgs.clear();
-
   visitGlobalValue(F);
 
   // Check function arguments.
@@ -4354,8 +4348,6 @@ void Verifier::visitDbgIntrinsic(StringRef Kind, DbgIntrinsicTy &DII) {
                                " variable and !dbg attachment",
            &DII, BB, F, Var, Var->getScope()->getSubprogram(), Loc,
            Loc->getScope()->getSubprogram());
-
-  verifyFnArgs(DII);
 }
 
 static uint64_t getVariableSize(const DILocalVariable &V) {
@@ -4424,36 +4416,6 @@ void Verifier::verifyFragmentExpression(const DbgInfoIntrinsic &I) {
   AssertDI(FragSize != VarSize, "fragment covers entire variable", &I, V, E);
 }
 
-void Verifier::verifyFnArgs(const DbgInfoIntrinsic &I) {
-  DILocalVariable *Var;
-  if (auto *DV = dyn_cast<DbgValueInst>(&I)) {
-    // For performance reasons only check non-inlined ones.
-    if (DV->getDebugLoc()->getInlinedAt())
-      return;
-    Var = DV->getVariable();
-  } else {
-    auto *DD = cast<DbgDeclareInst>(&I);
-    if (DD->getDebugLoc()->getInlinedAt())
-      return;
-    Var = DD->getVariable();
-  }
-  AssertDI(Var, "dbg intrinsic without variable");
-
-  unsigned ArgNo = Var->getArg();
-  if (!ArgNo)
-    return;
-
-  // Verify there are no duplicate function argument debug info entries.
-  // These will cause hard-to-debug assertions in the DWARF backend.
-  if (DebugFnArgs.size() < ArgNo)
-    DebugFnArgs.resize(ArgNo, nullptr);
-
-  auto *Prev = DebugFnArgs[ArgNo - 1];
-  DebugFnArgs[ArgNo - 1] = Var;
-  AssertDI(!Prev || (Prev == Var), "conflicting debug info for argument", &I,
-           Prev, Var);
-}
-
 void Verifier::verifyCompileUnits() {
   auto *CUs = M.getNamedMetadata("llvm.dbg.cu");
   SmallPtrSet<const Metadata *, 2> Listed;