Allow getting all source locations of selector identifiers in a ObjCMessageExpr.

Instead of always storing all source locations for the selector identifiers
we check whether all the identifiers are in a "standard" position; "standard" position is

  -Immediately before the arguments: [foo first:1 second:2]
  -With a space between the arguments: [foo first: 1 second: 2]
  -For nullary selectors, immediately before ']': [foo release]

In such cases we infer the locations instead of storing them.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@140987 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 102 insertions, 0 deletions

diff --git a/lib/AST/SelectorLocationsKind.cpp b/lib/AST/SelectorLocationsKind.cpp
new file mode 100644
index 0000000000..cafb105e99
--- /dev/null
+++ b/lib/AST/SelectorLocationsKind.cpp
@@ -0,0 +1,102 @@
+//===--- SelectorLocationsKind.cpp - Kind of selector locations -*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Describes whether the identifier locations for a selector are "standard"
+// or not.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/SelectorLocationsKind.h"
+#include "clang/AST/Expr.h"
+
+using namespace clang;
+
+static SourceLocation getStandardSelLoc(unsigned Index,
+                                        Selector Sel,
+                                        bool WithArgSpace,
+                                        SourceLocation ArgLoc,
+                                        SourceLocation EndLoc) {
+  unsigned NumSelArgs = Sel.getNumArgs();
+  if (NumSelArgs == 0) {
+    assert(Index == 0);
+    if (EndLoc.isInvalid())
+      return SourceLocation();
+    IdentifierInfo *II = Sel.getIdentifierInfoForSlot(0);
+    unsigned Len = II ? II->getLength() : 0;
+    return EndLoc.getLocWithOffset(-Len);
+  }
+
+  assert(Index < NumSelArgs);
+  if (ArgLoc.isInvalid())
+    return SourceLocation();
+  IdentifierInfo *II = Sel.getIdentifierInfoForSlot(Index);
+  unsigned Len = /* selector id */ (II ? II->getLength() : 0) + /* ':' */ 1;
+  if (WithArgSpace)
+    ++Len;
+  return ArgLoc.getLocWithOffset(-Len);
+}
+
+namespace {
+
+template <typename T>
+SourceLocation getArgLoc(T* Arg);
+
+template <>
+SourceLocation getArgLoc<Expr>(Expr *Arg) {
+  return Arg->getLocStart();
+}
+
+template <typename T>
+SourceLocation getArgLoc(unsigned Index, ArrayRef<T*> Args) {
+  return Index < Args.size() ? getArgLoc(Args[Index]) : SourceLocation();
+}
+
+template <typename T>
+SelectorLocationsKind hasStandardSelLocs(Selector Sel,
+                                         ArrayRef<SourceLocation> SelLocs,
+                                         ArrayRef<T *> Args,
+                                         SourceLocation EndLoc) {
+  // Are selector locations in standard position with no space between args ?
+  unsigned i;
+  for (i = 0; i != SelLocs.size(); ++i) {
+    if (SelLocs[i] != getStandardSelectorLoc(i, Sel, /*WithArgSpace=*/false,
+                                             Args, EndLoc))
+      break;
+  }
+  if (i == SelLocs.size())
+    return SelLoc_StandardNoSpace;
+
+  // Are selector locations in standard position with space between args ?
+  for (i = 0; i != SelLocs.size(); ++i) {
+    if (SelLocs[i] != getStandardSelectorLoc(i, Sel, /*WithArgSpace=*/true,
+                                             Args, EndLoc))
+      return SelLoc_NonStandard;
+  }
+
+  return SelLoc_StandardWithSpace;
+}
+
+} // anonymous namespace
+
+SelectorLocationsKind
+clang::hasStandardSelectorLocs(Selector Sel,
+                               ArrayRef<SourceLocation> SelLocs,
+                               ArrayRef<Expr *> Args,
+                               SourceLocation EndLoc) {
+  return hasStandardSelLocs(Sel, SelLocs, Args, EndLoc);
+}
+
+SourceLocation clang::getStandardSelectorLoc(unsigned Index,
+                                             Selector Sel,
+                                             bool WithArgSpace,
+                                             ArrayRef<Expr *> Args,
+                                             SourceLocation EndLoc) {
+  return getStandardSelLoc(Index, Sel, WithArgSpace,
+                           getArgLoc(Index, Args), EndLoc);
+}