Implement allocation and sizeof VLAs. This is very basic for now.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@60943 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index 9352c35..62684ba 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -20,6 +20,7 @@
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/GlobalVariable.h"
+#include "llvm/Intrinsics.h"
#include "llvm/Type.h"
using namespace clang;
using namespace CodeGen;
@@ -160,13 +161,37 @@
DeclPtr = GenerateStaticBlockVarDecl(D, true, Class);
}
} else {
- CGM.ErrorUnsupported(&D, "variable-length array");
+ const VariableArrayType *VAT = getContext().getAsVariableArrayType(Ty);
- // FIXME: VLA: Add VLA support. For now just make up enough to let
- // the compile go through.
- const llvm::Type *LTy = ConvertType(Ty);
+ if (!StackSaveValues.back()) {
+ // Save the stack.
+ const llvm::Type *LTy = llvm::PointerType::getUnqual(llvm::Type::Int8Ty);
+ llvm::Value *Stack = CreateTempAlloca(LTy, "saved_stack");
+
+ llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stacksave);
+ llvm::Value *V = Builder.CreateCall(F);
+
+ Builder.CreateStore(V, Stack);
+
+ StackSaveValues.back() = Stack;
+ }
+ // Get the element type.
+ const llvm::Type *LElemTy = ConvertType(Ty);
+ const llvm::Type *LElemPtrTy =
+ llvm::PointerType::get(LElemTy, D.getType().getAddressSpace());
+
+ llvm::Value *VLASize = GetVLASize(VAT);
+
+ // Allocate memory for the array.
+ llvm::Value *VLA = Builder.CreateAlloca(llvm::Type::Int8Ty, VLASize, "vla");
+ VLA = Builder.CreateBitCast(VLA, LElemPtrTy, "tmp");
+
llvm::AllocaInst *Alloc =
- CreateTempAlloca(LTy, D.getIdentifier()->getName());
+ CreateTempAlloca(LElemPtrTy, D.getIdentifier()->getName());
+
+ // FIXME: Volatile?
+ Builder.CreateStore(VLA, Alloc);
+
DeclPtr = Alloc;
}