Import LLVM 10.0.0 release including clang, lld and lldb.

ok hackroom
tested by plenty

1 files changed, 98 insertions, 0 deletions

diff --git a/gnu/llvm/clang/lib/Tooling/Syntax/Mutations.cpp b/gnu/llvm/clang/lib/Tooling/Syntax/Mutations.cpp
new file mode 100644
index 00000000000..72458528202
--- /dev/null
+++ b/gnu/llvm/clang/lib/Tooling/Syntax/Mutations.cpp
@@ -0,0 +1,98 @@
+//===- Mutations.cpp ------------------------------------------*- C++ -*-=====//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include "clang/Tooling/Syntax/Mutations.h"
+#include "clang/Basic/LLVM.h"
+#include "clang/Basic/SourceLocation.h"
+#include "clang/Lex/Token.h"
+#include "clang/Tooling/Core/Replacement.h"
+#include "clang/Tooling/Syntax/BuildTree.h"
+#include "clang/Tooling/Syntax/Nodes.h"
+#include "clang/Tooling/Syntax/Tokens.h"
+#include "clang/Tooling/Syntax/Tree.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/Casting.h"
+#include <cassert>
+#include <string>
+
+using namespace clang;
+
+// This class has access to the internals of tree nodes. Its sole purpose is to
+// define helpers that allow implementing the high-level mutation operations.
+class syntax::MutationsImpl {
+public:
+  /// Add a new node with a specified role.
+  static void addAfter(syntax::Node *Anchor, syntax::Node *New, NodeRole Role) {
+    assert(Anchor != nullptr);
+    assert(New->Parent == nullptr);
+    assert(New->NextSibling == nullptr);
+    assert(!New->isDetached());
+    assert(Role != NodeRole::Detached);
+
+    New->Role = static_cast<unsigned>(Role);
+    auto *P = Anchor->parent();
+    P->replaceChildRangeLowLevel(Anchor, Anchor, New);
+
+    P->assertInvariants();
+  }
+
+  /// Replace the node, keeping the role.
+  static void replace(syntax::Node *Old, syntax::Node *New) {
+    assert(Old != nullptr);
+    assert(Old->Parent != nullptr);
+    assert(Old->canModify());
+    assert(New->Parent == nullptr);
+    assert(New->NextSibling == nullptr);
+    assert(New->isDetached());
+
+    New->Role = Old->Role;
+    auto *P = Old->parent();
+    P->replaceChildRangeLowLevel(findPrevious(Old), Old->nextSibling(), New);
+
+    P->assertInvariants();
+  }
+
+  /// Completely remove the node from its parent.
+  static void remove(syntax::Node *N) {
+    auto *P = N->parent();
+    P->replaceChildRangeLowLevel(findPrevious(N), N->nextSibling(),
+                                 /*New=*/nullptr);
+
+    P->assertInvariants();
+    N->assertInvariants();
+  }
+
+private:
+  static syntax::Node *findPrevious(syntax::Node *N) {
+    if (N->parent()->firstChild() == N)
+      return nullptr;
+    for (syntax::Node *C = N->parent()->firstChild(); C != nullptr;
+         C = C->nextSibling()) {
+      if (C->nextSibling() == N)
+        return C;
+    }
+    llvm_unreachable("could not find a child node");
+  }
+};
+
+void syntax::removeStatement(syntax::Arena &A, syntax::Statement *S) {
+  assert(S);
+  assert(S->canModify());
+
+  if (isa<CompoundStatement>(S->parent())) {
+    // A child of CompoundStatement can just be safely removed.
+    MutationsImpl::remove(S);
+    return;
+  }
+  // For the rest, we have to replace with an empty statement.
+  if (isa<EmptyStatement>(S))
+    return; // already an empty statement, nothing to do.
+
+  MutationsImpl::replace(S, createEmptyStatement(A));
+}