Re-land r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare"

The fix is to avoid invalidating our insertion point in
replaceDbgDeclare:
     Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore);
+    if (DII == InsertBefore)
+      InsertBefore = &*std::next(InsertBefore->getIterator());
     DII->eraseFromParent();

I had to write a unit tests for this instead of a lit test because the
use list order matters in order to trigger the bug.

The reduced C test case for this was:
  void useit(int*);
  static inline void inlineme() {
    int x[2];
    useit(x);
  }
  void f() {
    inlineme();
    inlineme();
  }

llvm-svn: 313905

2 files changed, 14 insertions, 2 deletions

diff --git a/llvm/lib/IR/DIBuilder.cpp b/llvm/lib/IR/DIBuilder.cpp
index 1a40d5ce13d..88f5b36dd58 100644
--- a/llvm/lib/IR/DIBuilder.cpp
+++ b/llvm/lib/IR/DIBuilder.cpp
@@ -24,6 +24,11 @@
 using namespace llvm;
 using namespace llvm::dwarf;
 
+cl::opt<bool>
+    UseDbgAddr("use-dbg-addr",
+                llvm::cl::desc("Use llvm.dbg.addr for all local variables"),
+                cl::init(false));
+
 DIBuilder::DIBuilder(Module &m, bool AllowUnresolvedNodes)
   : M(m), VMContext(M.getContext()), CUNode(nullptr),
       DeclareFn(nullptr), ValueFn(nullptr),
@@ -776,6 +781,11 @@ static Instruction *withDebugLoc(Instruction *I, const DILocation *DL) {
   return I;
 }
 
+static Function *getDeclareIntrin(Module &M) {
+  return Intrinsic::getDeclaration(&M, UseDbgAddr ? Intrinsic::dbg_addr
+                                                  : Intrinsic::dbg_declare);
+}
+
 Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
                                       DIExpression *Expr, const DILocation *DL,
                                       Instruction *InsertBefore) {
@@ -785,7 +795,7 @@ Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
              VarInfo->getScope()->getSubprogram() &&
          "Expected matching subprograms");
   if (!DeclareFn)
-    DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
+    DeclareFn = getDeclareIntrin(M);
 
   trackIfUnresolved(VarInfo);
   trackIfUnresolved(Expr);
@@ -804,7 +814,7 @@ Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
              VarInfo->getScope()->getSubprogram() &&
          "Expected matching subprograms");
   if (!DeclareFn)
-    DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
+    DeclareFn = getDeclareIntrin(M);
 
   trackIfUnresolved(VarInfo);
   trackIfUnresolved(Expr);
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index c875e302188..9f671e41a18 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -4001,6 +4001,8 @@ void Verifier::visitIntrinsicCallSite(Intrinsic::ID ID, CallSite CS) {
            "invalid llvm.dbg.declare intrinsic call 1", CS);
     visitDbgIntrinsic("declare", cast<DbgInfoIntrinsic>(*CS.getInstruction()));
     break;
+  case Intrinsic::dbg_addr: // llvm.dbg.addr
+    visitDbgIntrinsic("addr", cast<DbgInfoIntrinsic>(*CS.getInstruction()));
   case Intrinsic::dbg_value: // llvm.dbg.value
     visitDbgIntrinsic("value", cast<DbgInfoIntrinsic>(*CS.getInstruction()));
     break;