Merge commit 'ef3526facfc0' from apple/stable/20200714 into swift/main

Author: git apple-llvm automerger

clang/lib/Driver/ToolChains/Darwin.cpp

@@ -2098,21 +2098,42 @@ void DarwinClang::AddClangCXXStdlibIncludeArgs(
 
   switch (GetCXXStdlibType(DriverArgs)) {
   case ToolChain::CST_Libcxx: {
-    // On Darwin, libc++ is installed alongside the compiler in
-    // include/c++/v1, so get from '<install>/bin' to '<install>/include/c++/v1'.
-    {
-      llvm::SmallString<128> P = llvm::StringRef(getDriver().getInstalledDir());
-      // Note that P can be relative, so we have to '..' and not parent_path.
-      llvm::sys::path::append(P, "..", "include", "c++", "v1");
-      addSystemInclude(DriverArgs, CC1Args, P);
+    // On Darwin, libc++ can be installed in one of the following two places:
+    // 1. Alongside the compiler in         <install>/include/c++/v1
+    // 2. In a SDK (or a custom sysroot) in <sysroot>/usr/include/c++/v1
+    //
+    // The precendence of paths is as listed above, i.e. we take the first path
+    // that exists. Also note that we never include libc++ twice -- we take the
+    // first path that exists and don't send the other paths to CC1 (otherwise
+    // include_next could break).
+
+    // Check for (1)
+    // Get from '<install>/bin' to '<install>/include/c++/v1'.
+    // Note that InstallBin can be relative, so we use '..' instead of
+    // parent_path.
+    llvm::SmallString<128> InstallBin =
+        llvm::StringRef(getDriver().getInstalledDir()); // <install>/bin
+    llvm::sys::path::append(InstallBin, "..", "include", "c++", "v1");
+    if (getVFS().exists(InstallBin)) {
+      addSystemInclude(DriverArgs, CC1Args, InstallBin);
+      return;
+    } else if (DriverArgs.hasArg(options::OPT_v)) {
+      llvm::errs() << "ignoring nonexistent directory \"" << InstallBin
+                   << "\"\n";
     }
-    // Also add <sysroot>/usr/include/c++/v1 unless -nostdinc is used,
-    // to match the legacy behavior in CC1.
-    if (!DriverArgs.hasArg(options::OPT_nostdinc)) {
-      llvm::SmallString<128> P = Sysroot;
-      llvm::sys::path::append(P, "usr", "include", "c++", "v1");
-      addSystemInclude(DriverArgs, CC1Args, P);
+
+    // Otherwise, check for (2)
+    llvm::SmallString<128> SysrootUsr = Sysroot;
+    llvm::sys::path::append(SysrootUsr, "usr", "include", "c++", "v1");
+    if (getVFS().exists(SysrootUsr)) {
+      addSystemInclude(DriverArgs, CC1Args, SysrootUsr);
+      return;
+    } else if (DriverArgs.hasArg(options::OPT_v)) {
+      llvm::errs() << "ignoring nonexistent directory \"" << SysrootUsr
+                   << "\"\n";
     }
+
+    // Otherwise, don't add any path.
     break;
   }
 

clang/test/Driver/Inputs/basic_darwin_sdk_usr_cxx_v1/usr/include/c++/v1/.keep

@@ -13,39 +13,57 @@
 // RUN:   | FileCheck --check-prefix=CHECK-LIBCXX-NONE %s
 // CHECK-LIBCXX-NONE: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
 
-// Check with only headers alongside the installation (those should be used,
-// but we should still add /usr/include/c++/v1 after to preserve legacy).
+// Check with only headers alongside the installation (those should be used).
 //
 // RUN: %clang -no-canonical-prefixes %s -### -fsyntax-only 2>&1 \
 // RUN:     -target x86_64-apple-darwin \
 // RUN:     -stdlib=libc++ \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin \
 // RUN:     --sysroot="" \
-// RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain --check-prefix=CHECK-LIBCXX-TOOLCHAIN-1 %s
+// RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain \
+// RUN:               --check-prefix=CHECK-LIBCXX-TOOLCHAIN-1 %s
 // CHECK-LIBCXX-TOOLCHAIN-1: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
 // CHECK-LIBCXX-TOOLCHAIN-1: "-internal-isystem" "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
-// CHECK-LIBCXX-TOOLCHAIN-1: "-internal-isystem" "/usr/include/c++/v1"
+// CHECK-LIBCXX-TOOLCHAIN-1-NOT: "-internal-isystem" "/usr/include/c++/v1"
 //
 // RUN: %clang -no-canonical-prefixes %s -### -fsyntax-only 2>&1 \
 // RUN:     -target x86_64-apple-darwin \
 // RUN:     -stdlib=libc++ \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin \
 // RUN:     -isysroot %S/Inputs/basic_darwin_sdk_no_libcxx \
-// RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain --check-prefix=CHECK-LIBCXX-TOOLCHAIN-2 %s
+// RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain \
+// RUN:               -DSYSROOT=%S/Inputs/basic_darwin_sdk_no_libcxx \
+// RUN:               --check-prefix=CHECK-LIBCXX-TOOLCHAIN-2 %s
 // CHECK-LIBCXX-TOOLCHAIN-2: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
 // CHECK-LIBCXX-TOOLCHAIN-2: "-internal-isystem" "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
+// CHECK-LIBCXX-TOOLCHAIN-2-NOT: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
+
+// Check with only headers in the sysroot (those should be used).
+//
+// RUN: %clang -no-canonical-prefixes %s -### -fsyntax-only 2>&1 \
+// RUN:     -target x86_64-apple-darwin \
+// RUN:     -stdlib=libc++ \
+// RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain_no_libcxx/usr/bin \
+// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
+// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
+// RUN:               -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain_no_libcxx \
+// RUN:               --check-prefix=CHECK-LIBCXX-SYSROOT-1 %s
+// CHECK-LIBCXX-SYSROOT-1: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
+// CHECK-LIBCXX-SYSROOT-1: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
+// CHECK-LIBCXX-SYSROOT-1-NOT: "-internal-isystem" "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
 
 // Check with both headers in the sysroot and headers alongside the installation
-// (the headers in <sysroot> should be added after the toolchain headers).
-// Ensure that both -isysroot and --sysroot work, and that isysroot has precedence.
+// (the headers in the toolchain should be preferred over the <sysroot> headers).
+// Ensure that both -isysroot and --sysroot work, and that isysroot has precedence
+// over --sysroot.
 //
 // RUN: %clang -no-canonical-prefixes %s -### -fsyntax-only 2>&1 \
 // RUN:     -target x86_64-apple-darwin \
 // RUN:     -stdlib=libc++ \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
-// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr \
-// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr \
+// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
+// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
 // RUN:               -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain \
 // RUN:               --check-prefix=CHECK-LIBCXX-SYSROOT_AND_TOOLCHAIN-1 %s
 //
@@ -54,8 +72,8 @@
 // RUN:     -stdlib=libc++ \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
-// RUN:     --sysroot %S/Inputs/basic_darwin_sdk_usr \
-// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr \
+// RUN:     --sysroot %S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
+// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
 // RUN:               -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain \
 // RUN:               --check-prefix=CHECK-LIBCXX-SYSROOT_AND_TOOLCHAIN-1 %s
 //
@@ -64,32 +82,46 @@
 // RUN:     -stdlib=libc++ \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
-// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr \
+// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
 // RUN:     --sysroot %S/Inputs/basic_darwin_sdk_no_libcxx \
-// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr \
+// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
 // RUN:               -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain \
 // RUN:               --check-prefix=CHECK-LIBCXX-SYSROOT_AND_TOOLCHAIN-1 %s
 //
 // CHECK-LIBCXX-SYSROOT_AND_TOOLCHAIN-1: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
 // CHECK-LIBCXX-SYSROOT_AND_TOOLCHAIN-1: "-internal-isystem" "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
-// CHECK-LIBCXX-SYSROOT_AND_TOOLCHAIN-1: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
+// CHECK-LIBCXX-SYSROOT_AND_TOOLCHAIN-1-NOT: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
 
-// Make sure that using -nostdinc will drop the sysroot C++ library include
-// path, but not the toolchain one.
+// Make sure that using -nostdinc does not drop any C++ library include path.
+// This behavior is strange, but it is compatible with the legacy CC1 behavior.
 //
 // RUN: %clang -no-canonical-prefixes %s -### -fsyntax-only 2>&1 \
 // RUN:     -target x86_64-apple-darwin16 \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
-// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr \
+// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
 // RUN:     -stdlib=platform \
 // RUN:     -nostdinc \
-// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr \
+// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
 // RUN:               -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain \
-// RUN:               --check-prefix=CHECK-LIBCXX-NOSTDINC %s
-// CHECK-LIBCXX-NOSTDINC: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
-// CHECK-LIBCXX-NOSTDINC: "-internal-isystem" "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
-// CHECK-LIBCXX-NOSTDINC-NOT: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
+// RUN:               --check-prefix=CHECK-LIBCXX-NOSTDINC-1 %s
+// CHECK-LIBCXX-NOSTDINC-1: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
+// CHECK-LIBCXX-NOSTDINC-1-NOT: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
+// CHECK-LIBCXX-NOSTDINC-1: "-internal-isystem" "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
+//
+// RUN: %clang -no-canonical-prefixes %s -### -fsyntax-only 2>&1 \
+// RUN:     -target x86_64-apple-darwin16 \
+// RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin \
+// RUN:     -resource-dir=%S/Inputs/resource_dir \
+// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_no_libcxx \
+// RUN:     -stdlib=platform \
+// RUN:     -nostdinc \
+// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_no_libcxx \
+// RUN:               -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain \
+// RUN:               --check-prefix=CHECK-LIBCXX-NOSTDINC-2 %s
+// CHECK-LIBCXX-NOSTDINC-2: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
+// CHECK-LIBCXX-NOSTDINC-2: "-internal-isystem" "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
+// CHECK-LIBCXX-NOSTDINC-2-NOT: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
 
 // Make sure that using -nostdinc++ or -nostdlib will drop both the toolchain
 // C++ include path and the sysroot one.
@@ -98,7 +130,7 @@
 // RUN:     -target x86_64-apple-darwin16 \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir \
-// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr \
+// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_usr_cxx_v1 \
 // RUN:     -stdlib=platform \
 // RUN:     -nostdinc++ \
 // RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_usr \
@@ -121,3 +153,26 @@
 // CHECK-LIBCXX-NOSTDLIBINC: "{{[^"]*}}clang{{[^"]*}}" "-cc1"
 // CHECK-LIBCXX-NOSTDLIBINC-NOT: "-internal-isystem" "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
 // CHECK-LIBCXX-NOSTDLIBINC-NOT: "-internal-isystem" "[[SYSROOT]]/usr/include/c++/v1"
+
+// Make sure we explain that we considered a path but didn't add it when it
+// doesn't exist.
+//
+// RUN: %clang -no-canonical-prefixes %s -fsyntax-only -v 2>&1 \
+// RUN:     -target x86_64-apple-darwin \
+// RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain_no_libcxx/usr/bin \
+// RUN:     -isysroot %S/Inputs/basic_darwin_sdk \
+// RUN:     -stdlib=libc++ \
+// RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain_no_libcxx \
+// RUN:               --check-prefix=CHECK-LIBCXX-MISSING-TOOLCHAIN %s
+// CHECK-LIBCXX-MISSING-TOOLCHAIN: ignoring nonexistent directory "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
+//
+// RUN: %clang -no-canonical-prefixes %s -fsyntax-only -v 2>&1 \
+// RUN:     -target x86_64-apple-darwin \
+// RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain_no_libcxx/usr/bin \
+// RUN:     -isysroot %S/Inputs/basic_darwin_sdk_no_libcxx \
+// RUN:     -stdlib=libc++ \
+// RUN:   | FileCheck -DSYSROOT=%S/Inputs/basic_darwin_sdk_no_libcxx \
+// RUN:               -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain_no_libcxx \
+// RUN:               --check-prefix=CHECK-LIBCXX-MISSING-BOTH %s
+// CHECK-LIBCXX-MISSING-BOTH: ignoring nonexistent directory "[[TOOLCHAIN]]/usr/bin/../include/c++/v1"
+// CHECK-LIBCXX-MISSING-BOTH: ignoring nonexistent directory "[[SYSROOT]]/usr/include/c++/v1"

clang/test/Driver/Inputs/basic_darwin_sdk_usr_cxx_v1/usr/lib/.keep

@@ -9700,14 +9700,15 @@ GetSpecializedASTName(ScratchTypeSystemClang::IsolatedASTKind feature) {
 }
 
 TypeSystemClang &ScratchTypeSystemClang::GetIsolatedAST(
-    ScratchTypeSystemClang::IsolatedASTKind feature) {
+    ScratchTypeSystemClang::IsolatedASTKind feature_enum) {
+  int feature = static_cast<int>(feature_enum);
   auto found_ast = m_isolated_asts.find(feature);
   if (found_ast != m_isolated_asts.end())
     return *found_ast->second;
 
   // Couldn't find the requested sub-AST, so create it now.
   std::unique_ptr<TypeSystemClang> new_ast;
-  new_ast.reset(new SpecializedScratchAST(GetSpecializedASTName(feature),
+  new_ast.reset(new SpecializedScratchAST(GetSpecializedASTName(feature_enum),
                                           m_triple, CreateASTSource()));
   m_isolated_asts[feature] = std::move(new_ast);
   return *m_isolated_asts[feature];

clang/test/Driver/darwin-header-search-libcxx.cpp

@@ -1237,7 +1237,7 @@ class ScratchTypeSystemClang : public TypeSystemClang {
   /// Map from IsolatedASTKind to their actual TypeSystemClang instance.
   /// This map is lazily filled with sub-ASTs and should be accessed via
   /// `GetSubAST` (which lazily fills this map).
-  std::unordered_map<IsolatedASTKind, std::unique_ptr<TypeSystemClang>>
+  std::unordered_map<int, std::unique_ptr<TypeSystemClang>>
       m_isolated_asts;
 };
 

lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp

@@ -804,6 +804,7 @@ static Instruction *insertSpills(const SpillInfo &Spills, coro::Shape &Shape) {
                                     CurrentValue->getName() + Twine(".reload"));
   };
 
+  SmallDenseMap<llvm::Value *, llvm::AllocaInst *, 4> DbgPtrAllocaCache;
   Value *GEP = nullptr, *CurrentGEP = nullptr;
   for (auto const &E : Spills) {
     // If we have not seen the value, generate a spill.
@@ -896,12 +897,21 @@ static Instruction *insertSpills(const SpillInfo &Spills, coro::Shape &Shape) {
     if (CurrentGEP != GEP) {
       CurrentGEP = GEP;
       TinyPtrVector<DbgDeclareInst *> DIs = FindDbgDeclareUses(CurrentValue);
-      if (!DIs.empty())
-        DIBuilder(*CurrentBlock->getParent()->getParent(),
-                  /*AllowUnresolved*/ false)
-            .insertDeclare(CurrentGEP, DIs.front()->getVariable(),
-                           DIs.front()->getExpression(),
-                           DIs.front()->getDebugLoc(), DIs.front());
+      if (!DIs.empty()) {
+        auto *DDI = DIs.front();
+        bool AllowUnresolved = false;
+        // This dbg.declare is preserved for all coro-split function
+        // fragments. It will be unreachable in the main function, and
+        // processed by coro::salvageDebugInfo() by CoroCloner.
+        DIBuilder(*CurrentBlock->getParent()->getParent(), AllowUnresolved)
+            .insertDeclare(CurrentGEP, DDI->getVariable(),
+                           DDI->getExpression(),
+                           DDI->getDebugLoc(),
+                           &*Builder.GetInsertPoint());
+        // This dbg.declare is for the main function entry point.  It
+        // will be deleted in all coro-split functions.
+        coro::salvageDebugInfo(DbgPtrAllocaCache, DDI);
+      }
     }
 
     // Replace all uses of CurrentValue in the current instruction with reload.
@@ -1633,6 +1643,55 @@ static void sinkLifetimeStartMarkers(Function &F, coro::Shape &Shape,
   }
 }
 
+void coro::salvageDebugInfo(
+    SmallDenseMap<llvm::Value *, llvm::AllocaInst *, 4> &DbgPtrAllocaCache,
+    DbgDeclareInst *DDI, bool LoadFromFramePtr) {
+  Function *F = DDI->getFunction();
+  IRBuilder<> Builder(F->getContext());
+  auto InsertPt = F->getEntryBlock().getFirstInsertionPt();
+  while (isa<IntrinsicInst>(InsertPt))
+    ++InsertPt;
+  Builder.SetInsertPoint(&F->getEntryBlock(), InsertPt);
+  DIExpression *Expr = DDI->getExpression();
+  // Follow the pointer arithmetic all the way to the incoming
+  // function argument and convert into a DIExpression.
+  Value *Storage = DDI->getAddress();
+  while (Storage) {
+    if (auto *LdInst = dyn_cast<LoadInst>(Storage)) {
+      Storage = LdInst->getOperand(0);
+    } else if (auto *GEPInst = dyn_cast<GetElementPtrInst>(Storage)) {
+      Expr = llvm::salvageDebugInfoImpl(*GEPInst, Expr,
+                                        /*WithStackValue=*/false);
+      Storage = GEPInst->getOperand(0);
+    } else if (auto *BCInst = dyn_cast<llvm::BitCastInst>(Storage))
+      Storage = BCInst->getOperand(0);
+    else
+      break;
+  }
+  // Store a pointer to the coroutine frame object in an alloca so it
+  // is available throughout the function when producing unoptimized
+  // code. Extending the lifetime this way is correct because the
+  // variable has been declared by a dbg.declare intrinsic.
+  if (auto Arg = dyn_cast_or_null<llvm::Argument>(Storage)) {
+    auto &Cached = DbgPtrAllocaCache[Storage];
+    if (!Cached) {
+      Cached = Builder.CreateAlloca(Storage->getType(), 0, nullptr,
+                                    Arg->getName() + ".debug");
+      Builder.CreateStore(Storage, Cached);
+    }
+    Storage = Cached;
+    Expr = DIExpression::prepend(Expr, DIExpression::DerefBefore);
+  }
+  // The FramePtr object adds one extra layer of indirection that
+  // needs to be unwrapped.
+  if (LoadFromFramePtr)
+    Expr = DIExpression::prepend(Expr, DIExpression::DerefBefore);
+  auto &VMContext = DDI->getFunction()->getContext();
+  DDI->setOperand(
+      0, MetadataAsValue::get(VMContext, ValueAsMetadata::get(Storage)));
+  DDI->setOperand(2, MetadataAsValue::get(VMContext, Expr));
+}
+
 void coro::buildCoroutineFrame(Function &F, Shape &Shape) {
   eliminateSwiftError(F, Shape);
 

lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h

@@ -52,6 +52,11 @@ void replaceAllCoroFrees(CoroBeginInst *CB, Value *Replacement);
 void replaceCoroFree(CoroIdInst *CoroId, bool Elide);
 void updateCallGraph(Function &Caller, ArrayRef<Function *> Funcs,
                      CallGraph &CG, CallGraphSCC &SCC);
+/// Recover a dbg.declare prepared by the frontend and emit an alloca
+/// holding a pointer to the coroutine frame.
+void salvageDebugInfo(
+    SmallDenseMap<llvm::Value *, llvm::AllocaInst *, 4> &DbgPtrAllocaCache,
+    DbgDeclareInst *DDI, bool LoadFromCoroFrame = false);
 
 // Keeps data and helper functions for lowering coroutine intrinsics.
 struct LowererBase {