1 files changed, 94 insertions, 3 deletions

diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 6eac5b6a936..d6e6ab4ec86 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -4608,6 +4608,83 @@ static bool checkArgsForPlaceholders(Sema &S, MultiExprArg args) {
   return hasInvalid;
 }
 
+/// If a builtin function has a pointer argument with no explicit address
+/// space, than it should be able to accept a pointer to any address
+/// space as input.  In order to do this, we need to replace the
+/// standard builtin declaration with one that uses the same address space
+/// as the call.
+///
+/// \returns nullptr If this builtin is not a candidate for a rewrite i.e.
+///                  it does not contain any pointer arguments without
+///                  an address space qualifer.  Otherwise the rewritten
+///                  FunctionDecl is returned.
+/// TODO: Handle pointer return types.
+static FunctionDecl *rewriteBuiltinFunctionDecl(Sema *Sema, ASTContext &Context,
+                                                const FunctionDecl *FDecl,
+                                                MultiExprArg ArgExprs) {
+
+  QualType DeclType = FDecl->getType();
+  const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(DeclType);
+
+  if (!Context.BuiltinInfo.hasPtrArgsOrResult(FDecl->getBuiltinID()) ||
+      !FT || FT->isVariadic() || ArgExprs.size() != FT->getNumParams())
+    return nullptr;
+
+  bool NeedsNewDecl = false;
+  unsigned i = 0;
+  SmallVector<QualType, 8> OverloadParams;
+
+  for (QualType ParamType : FT->param_types()) {
+
+    // Convert array arguments to pointer to simplify type lookup.
+    Expr *Arg = Sema->DefaultFunctionArrayLvalueConversion(ArgExprs[i++]).get();
+    QualType ArgType = Arg->getType();
+    if (!ParamType->isPointerType() ||
+        ParamType.getQualifiers().hasAddressSpace() ||
+        !ArgType->isPointerType() ||
+        !ArgType->getPointeeType().getQualifiers().hasAddressSpace()) {
+      OverloadParams.push_back(ParamType);
+      continue;
+    }
+
+    NeedsNewDecl = true;
+    unsigned AS = ArgType->getPointeeType().getQualifiers().getAddressSpace();
+
+    QualType PointeeType = ParamType->getPointeeType();
+    PointeeType = Context.getAddrSpaceQualType(PointeeType, AS);
+    OverloadParams.push_back(Context.getPointerType(PointeeType));
+  }
+
+  if (!NeedsNewDecl)
+    return nullptr;
+
+  FunctionProtoType::ExtProtoInfo EPI;
+  QualType OverloadTy = Context.getFunctionType(FT->getReturnType(),
+                                                OverloadParams, EPI);
+  DeclContext *Parent = Context.getTranslationUnitDecl();
+  FunctionDecl *OverloadDecl = FunctionDecl::Create(Context, Parent,
+                                                    FDecl->getLocation(),
+                                                    FDecl->getLocation(),
+                                                    FDecl->getIdentifier(),
+                                                    OverloadTy,
+                                                    /*TInfo=*/nullptr,
+                                                    SC_Extern, false,
+                                                    /*hasPrototype=*/true);
+  SmallVector<ParmVarDecl*, 16> Params;
+  FT = cast<FunctionProtoType>(OverloadTy);
+  for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
+    QualType ParamType = FT->getParamType(i);
+    ParmVarDecl *Parm =
+        ParmVarDecl::Create(Context, OverloadDecl, SourceLocation(),
+                                SourceLocation(), nullptr, ParamType,
+                                /*TInfo=*/nullptr, SC_None, nullptr);
+    Parm->setScopeInfo(0, i);
+    Params.push_back(Parm);
+  }
+  OverloadDecl->setParams(Params);
+  return OverloadDecl;
+}
+
 /// ActOnCallExpr - Handle a call to Fn with the specified array of arguments.
 /// This provides the location of the left/right parens and a list of comma
 /// locations.
@@ -4711,10 +4788,24 @@ Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc,
   if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn))
     if (UnOp->getOpcode() == UO_AddrOf)
       NakedFn = UnOp->getSubExpr()->IgnoreParens();
-  
-  if (isa<DeclRefExpr>(NakedFn))
+
+  if (isa<DeclRefExpr>(NakedFn)) {
     NDecl = cast<DeclRefExpr>(NakedFn)->getDecl();
-  else if (isa<MemberExpr>(NakedFn))
+
+    FunctionDecl *FDecl = dyn_cast<FunctionDecl>(NDecl);
+    if (FDecl && FDecl->getBuiltinID()) {
+      // Rewrite the function decl for this builtin by replacing paramaters
+      // with no explicit address space with the address space of the arguments
+      // in ArgExprs.
+      if ((FDecl = rewriteBuiltinFunctionDecl(this, Context, FDecl, ArgExprs))) {
+        NDecl = FDecl;
+        Fn = DeclRefExpr::Create(Context, FDecl->getQualifierLoc(),
+                           SourceLocation(), FDecl, false,
+                           SourceLocation(), FDecl->getType(),
+                           Fn->getValueKind(), FDecl);
+      }
+    }
+  } else if (isa<MemberExpr>(NakedFn))
     NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl();
 
   if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(NDecl)) {