AltiVec-style vector initializer syntax, vec4 a = (vec4)(a, b, c, d);

In addition to being defined by the AltiVec PIM, this is also the vector
initializer syntax used by OpenCL, so that vector literals are compatible
with macro arguments.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@78535 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 4f7ae7e..e183e3a 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -50,6 +50,7 @@
   class Stmt;
   class Expr;
   class InitListExpr;
+  class ParenListExpr;
   class DesignatedInitExpr;
   class CallExpr;
   class DeclRefExpr;
@@ -1484,7 +1485,10 @@
   virtual OwningExprResult ActOnCharacterConstant(const Token &);
   virtual OwningExprResult ActOnParenExpr(SourceLocation L, SourceLocation R,
                                           ExprArg Val);
-
+  virtual OwningExprResult ActOnParenListExpr(SourceLocation L,
+                                              SourceLocation R,
+                                              MultiExprArg Val);
+  
   /// ActOnStringLiteral - The specified tokens were lexed as pasted string
   /// fragments (e.g. "foo" "bar" L"baz").
   virtual OwningExprResult ActOnStringLiteral(const Token *Toks,
@@ -1545,8 +1549,14 @@
                                          SourceLocation *CommaLocs,
                                          SourceLocation RParenLoc);
 
-  virtual OwningExprResult ActOnCastExpr(SourceLocation LParenLoc, TypeTy *Ty,
-                                         SourceLocation RParenLoc, ExprArg Op);
+  virtual OwningExprResult ActOnCastExpr(Scope *S, SourceLocation LParenLoc,
+                                         TypeTy *Ty, SourceLocation RParenLoc,
+                                         ExprArg Op);
+  
+  OwningExprResult ConvertParenListExpr(Scope *S, ParenListExpr *E);
+  OwningExprResult ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc,
+                                            SourceLocation RParenLoc,
+                                            ParenListExpr *E, QualType Ty);
 
   virtual OwningExprResult ActOnCompoundLiteral(SourceLocation LParenLoc,
                                                 TypeTy *Ty,
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index f00ab54..23e58de 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1918,7 +1918,8 @@
        << LHSExp->getSourceRange() << RHSExp->getSourceRange());
   }
   // C99 6.5.2.1p1
-  if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent())
+  if (!(IndexExpr->getType()->isIntegerType() &&
+        IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent())
     return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer)
                      << IndexExpr->getSourceRange());
 
@@ -2114,6 +2115,11 @@
   Expr *BaseExpr = Base.takeAs<Expr>();
   assert(BaseExpr && "no record expression");
 
+  // If BaseExpr is a ParenListExpr then convert it into a standard
+  // paren expr since this is not an altivec initializer.
+  if (ParenListExpr *PE = dyn_cast<ParenListExpr>(BaseExpr))
+    BaseExpr = ConvertParenListExpr(S, PE).takeAs<Expr>();
+  
   // Perform default conversions.
   DefaultFunctionArrayConversion(BaseExpr);
 
@@ -2689,6 +2695,11 @@
   FunctionDecl *FDecl = NULL;
   NamedDecl *NDecl = NULL;
   DeclarationName UnqualifiedName;
+  
+  // If the function is a ParenListExpr, then convert it into a standard
+  // paren expr since this is not an altivec initializer.
+  if (ParenListExpr *PE = dyn_cast<ParenListExpr>(Fn))
+    Fn = ConvertParenListExpr(S, PE).takeAs<Expr>();
 
   if (getLangOptions().CPlusPlus) {
     // Determine whether this is a dependent call inside a C++ template,
@@ -3090,7 +3101,7 @@
 }
 
 Action::OwningExprResult
-Sema::ActOnCastExpr(SourceLocation LParenLoc, TypeTy *Ty,
+Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty,
                     SourceLocation RParenLoc, ExprArg Op) {
   CastExpr::CastKind Kind = CastExpr::CK_Unknown;
   
@@ -3099,6 +3110,10 @@
 
   Expr *castExpr = Op.takeAs<Expr>();
   QualType castType = QualType::getFromOpaquePtr(Ty);
+  
+  // If the Expr being casted is a ParenListExpr, handle it specially.
+  if (ParenListExpr *PE = dyn_cast<ParenListExpr>(castExpr))
+    return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, PE, castType);
 
   if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr, 
                      Kind))
@@ -3108,6 +3123,68 @@
                                             LParenLoc, RParenLoc));
 }
 
+/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence
+/// of comma binary operators.
+Action::OwningExprResult
+Sema::ConvertParenListExpr(Scope *S, ParenListExpr *E) {
+  OwningExprResult Result(*this, E->getExpr(0));
+  
+  for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i)
+    Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result),
+                        Owned(E->getExpr(i)));
+  return move(Result);
+}
+
+Action::OwningExprResult
+Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc,
+                               SourceLocation RParenLoc,
+                               ParenListExpr *E, QualType Ty) {
+  // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 
+  // then handle it as such.
+  if (getLangOptions().AltiVec && Ty->isVectorType()) {
+    if (E->getNumExprs() == 0) {
+      Diag(E->getExprLoc(), diag::err_altivec_empty_initializer);
+      return ExprError();
+    }
+
+    llvm::SmallVector<Expr *, 8> initExprs;
+    for (unsigned i = 0, e = E->getNumExprs(); i != e; ++i)
+      initExprs.push_back(E->getExpr(i));
+
+    // FIXME: This means that pretty-printing the final AST will produce curly
+    // braces instead of the original commas.
+    InitListExpr *E = new (Context) InitListExpr(LParenLoc, &initExprs[0], 
+                                                 initExprs.size(), RParenLoc);
+    E->setType(Ty);
+    return ActOnCompoundLiteral(LParenLoc, Ty.getAsOpaquePtr(), RParenLoc, 
+                                Owned(E));
+  } else {
+    // This is not an AltiVec-style cast, so turn the ParenListExpr into a 
+    // sequence of BinOp comma operators.
+    OwningExprResult Result = ConvertParenListExpr(S, E);
+    Expr *castExpr = (Expr *)Result.get();
+    CastExpr::CastKind Kind = CastExpr::CK_Unknown;
+
+    if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty, castExpr, Kind))
+      return ExprError();
+    
+    return Owned(new (Context) CStyleCastExpr(Ty.getNonReferenceType(),
+                                              CastExpr::CK_Unknown, 
+                                              Result.takeAs<Expr>(), Ty,
+                                              LParenLoc, RParenLoc));
+  }
+}
+
+Action::OwningExprResult Sema::ActOnParenListExpr(SourceLocation L,
+                                                  SourceLocation R,
+                                                  MultiExprArg Val) {
+  unsigned nexprs = Val.size();
+  Expr **exprs = reinterpret_cast<Expr**>(Val.release());
+  assert((exprs != 0) && "ActOnParenListExpr() missing expr list");
+  Expr *expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R);
+  return Owned(expr);
+}
+
 /// Note that lhs is not null here, even if this is the gnu "x ?: y" extension.
 /// In that case, lhs = cond.
 /// C99 6.5.15
@@ -3132,6 +3209,8 @@
   }
 
   // Now check the two expressions.
+  if (LHSTy->isVectorType() || RHSTy->isVectorType())
+    return CheckVectorOperands(QuestionLoc, LHS, RHS);
 
   // If both operands have arithmetic type, do the usual arithmetic conversions
   // to find a common type: C99 6.5.15p3,5.
diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index 2911382..1e564ce 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -805,16 +805,47 @@
                                       unsigned &StructuredIndex) {
   if (Index < IList->getNumInits()) {
     const VectorType *VT = DeclType->getAsVectorType();
-    int maxElements = VT->getNumElements();
+    unsigned maxElements = VT->getNumElements();
+    unsigned numEltsInit = 0;
     QualType elementType = VT->getElementType();
     
-    for (int i = 0; i < maxElements; ++i) {
-      // Don't attempt to go past the end of the init list
-      if (Index >= IList->getNumInits())
-        break;
-      CheckSubElementType(IList, elementType, Index,
-                          StructuredList, StructuredIndex);
+    if (!SemaRef.getLangOptions().OpenCL) {
+      for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) {
+        // Don't attempt to go past the end of the init list
+        if (Index >= IList->getNumInits())
+          break;
+        CheckSubElementType(IList, elementType, Index,
+                            StructuredList, StructuredIndex);
+      }
+    } else {
+      // OpenCL initializers allows vectors to be constructed from vectors.
+      for (unsigned i = 0; i < maxElements; ++i) {
+        // Don't attempt to go past the end of the init list
+        if (Index >= IList->getNumInits())
+          break;
+        QualType IType = IList->getInit(Index)->getType();
+        if (!IType->isVectorType()) {
+          CheckSubElementType(IList, elementType, Index,
+                              StructuredList, StructuredIndex);
+          ++numEltsInit;
+        } else {
+          const VectorType *IVT = IType->getAsVectorType();
+          unsigned numIElts = IVT->getNumElements();
+          QualType VecType = SemaRef.Context.getExtVectorType(elementType,
+                                                              numIElts);
+          CheckSubElementType(IList, VecType, Index,
+                              StructuredList, StructuredIndex);
+          numEltsInit += numIElts;
+        }
+      }
     }
+    
+    // OpenCL & AltiVec require all elements to be initialized.
+    if (numEltsInit != maxElements)
+      if (SemaRef.getLangOptions().OpenCL || SemaRef.getLangOptions().AltiVec)
+        SemaRef.Diag(IList->getSourceRange().getBegin(),
+                     diag::err_vector_incorrect_num_initializers)
+          << (numEltsInit < maxElements) << maxElements << numEltsInit;
   }
 }
 
diff --git a/lib/Sema/SemaTemplateInstantiateExpr.cpp b/lib/Sema/SemaTemplateInstantiateExpr.cpp
index 186c98c..7a09210 100644
--- a/lib/Sema/SemaTemplateInstantiateExpr.cpp
+++ b/lib/Sema/SemaTemplateInstantiateExpr.cpp
@@ -639,6 +639,20 @@
 }
 
 Sema::OwningExprResult 
+TemplateExprInstantiator::VisitParenListExpr(ParenListExpr *E) {
+  ASTOwningVector<&ActionBase::DeleteExpr, 4> Inits(SemaRef);
+  for (unsigned I = 0, N = E->getNumExprs(); I != N; ++I) {
+    OwningExprResult Init = Visit(E->getExpr(I));
+    if (Init.isInvalid())
+      return SemaRef.ExprError();
+    Inits.push_back(Init.takeAs<Expr>());
+  }
+
+  return SemaRef.ActOnParenListExpr(E->getLParenLoc(), E->getRParenLoc(),
+                                    move_arg(Inits));
+}
+
+Sema::OwningExprResult 
 TemplateExprInstantiator::VisitDesignatedInitExpr(DesignatedInitExpr *E) {
   Designation Desig;
 
@@ -886,7 +900,7 @@
   if (SubExpr.isInvalid())
     return SemaRef.ExprError();
   
-  return SemaRef.ActOnCastExpr(E->getLParenLoc(), 
+  return SemaRef.ActOnCastExpr(/*Scope=*/0, E->getLParenLoc(), 
                                ExplicitTy.getAsOpaquePtr(),
                                E->getRParenLoc(),
                                move(SubExpr));