Make VLAs usable, and make basic usage work correctly. Also, add a
simple test that actually does VLA codegen.
Note that despite the fact that the alloca isn't in the entry block, it
should dominate all uses; this is guaranteed by the restrictions on goto
into VLA scope in C99.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@61291 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprScalar.cpp b/lib/CodeGen/CGExprScalar.cpp
index ffb5164..4984d0d 100644
--- a/lib/CodeGen/CGExprScalar.cpp
+++ b/lib/CodeGen/CGExprScalar.cpp
@@ -513,16 +513,14 @@
// FIXME: For now we assume that all source arrays map to LLVM arrays. This
// will not true when we add support for VLAs.
Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays.
-
- if (!(isa<llvm::PointerType>(V->getType()) &&
- isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType())
- ->getElementType()))) {
- CGF.ErrorUnsupported(E, "variable-length array cast", true);
- if (E->getType()->isVoidType())
- return 0;
- return llvm::UndefValue::get(CGF.ConvertType(E->getType()));
+
+ if (!Op->getType()->isVariableArrayType()) {
+ assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer");
+ assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType())
+ ->getElementType()) &&
+ "Expected pointer to array");
+ V = Builder.CreateStructGEP(V, 0, "arraydecay");
}
- V = Builder.CreateStructGEP(V, 0, "arraydecay");
// The resultant pointer type can be implicitly casted to other pointer
// types as well (e.g. void*) and can be implicitly converted to integer.