Debug Info: move StripDebugInfo from StripSymbols.cpp to DebugInfo.cpp.

We can share the implementation between StripSymbols and dropping debug info
for metadata versions that do not match.

Also update the comments to match the implementation. A follow-on patch will
drop the "Debug Info Version" module flag in StripDebugInfo.

llvm-svn: 195505

1 files changed, 52 insertions, 0 deletions

diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index 692e236b931..5dcc6f6590b 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -1426,3 +1426,55 @@ DIScopeRef DIDescriptor::getFieldAs<DIScopeRef>(unsigned Elt) const {
 template <> DITypeRef DIDescriptor::getFieldAs<DITypeRef>(unsigned Elt) const {
   return DITypeRef(getField(DbgNode, Elt));
 }
+
+/// Strip debug info in the module if it exists.
+/// To do this, we remove all calls to the debugger intrinsics and any named
+/// metadata for debugging. We also remove debug locations for instructions.
+/// Return true if module is modified.
+bool llvm::StripDebugInfo(Module &M) {
+
+  bool Changed = false;
+
+  // Remove all of the calls to the debugger intrinsics, and remove them from
+  // the module.
+  if (Function *Declare = M.getFunction("llvm.dbg.declare")) {
+    while (!Declare->use_empty()) {
+      CallInst *CI = cast<CallInst>(Declare->use_back());
+      CI->eraseFromParent();
+    }
+    Declare->eraseFromParent();
+    Changed = true;
+  }
+
+  if (Function *DbgVal = M.getFunction("llvm.dbg.value")) {
+    while (!DbgVal->use_empty()) {
+      CallInst *CI = cast<CallInst>(DbgVal->use_back());
+      CI->eraseFromParent();
+    }
+    DbgVal->eraseFromParent();
+    Changed = true;
+  }
+
+  for (Module::named_metadata_iterator NMI = M.named_metadata_begin(),
+         NME = M.named_metadata_end(); NMI != NME;) {
+    NamedMDNode *NMD = NMI;
+    ++NMI;
+    if (NMD->getName().startswith("llvm.dbg.")) {
+      NMD->eraseFromParent();
+      Changed = true;
+    }
+  }
+
+  for (Module::iterator MI = M.begin(), ME = M.end(); MI != ME; ++MI)
+    for (Function::iterator FI = MI->begin(), FE = MI->end(); FI != FE;
+         ++FI)
+      for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); BI != BE;
+           ++BI) {
+        if (!BI->getDebugLoc().isUnknown()) {
+          Changed = true;
+          BI->setDebugLoc(DebugLoc());
+        }
+      }
+
+  return Changed;
+}