[SYCL] Optionally override addrspace map for SYCL device code

Default address space (applies when no explicit address space was
specified) now maps to generic (4) address space.

Set ENABLE_INFER_AS=1 to enable this mode.

Signed-off-by: Andrew Savonichev <andrew.savonichev@intel.com>

Author: Andrew Savonichev

clang/lib/Basic/Targets/SPIR.h

@@ -38,14 +38,36 @@ static const unsigned SPIRAddrSpaceMap[] = {
     4, // sycl_generic
 };
 
+static const unsigned SYCLAddrSpaceMap[] = {
+    4, // Default
+    1, // opencl_global
+    3, // opencl_local
+    2, // opencl_constant
+    0, // opencl_private
+    4, // opencl_generic
+    0, // cuda_device
+    0, // cuda_constant
+    0, // cuda_shared
+    1, // sycl_global
+    3, // sycl_local
+    2, // sycl_constant
+    0, // sycl_private
+    4, // sycl_generic
+};
+
 class LLVM_LIBRARY_VISIBILITY SPIRTargetInfo : public TargetInfo {
 public:
   SPIRTargetInfo(const llvm::Triple &Triple, const TargetOptions &)
       : TargetInfo(Triple) {
     TLSSupported = false;
     VLASupported = false;
     LongWidth = LongAlign = 64;
-    AddrSpaceMap = &SPIRAddrSpaceMap;
+    if (Triple.getEnvironment() == llvm::Triple::SYCLDevice &&
+        getenv("ENABLE_INFER_AS")) {
+      AddrSpaceMap = &SYCLAddrSpaceMap;
+    } else {
+      AddrSpaceMap = &SPIRAddrSpaceMap;
+    }
     UseAddrSpaceMapMangling = true;
     HasLegalHalfType = true;
     HasFloat16 = true;

clang/lib/CodeGen/CGCall.cpp

@@ -4278,6 +4278,22 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
   if (!CallArgs.getCleanupsToDeactivate().empty())
     deactivateArgCleanupsBeforeCall(*this, CallArgs);
 
+  // Addrspace cast to generic if necessary
+  if (getenv("ENABLE_INFER_AS")) {
+    for (unsigned i = 0; i < IRFuncTy->getNumParams(); ++i) {
+      if (auto *PtrTy = dyn_cast<llvm::PointerType>(IRCallArgs[i]->getType())) {
+        auto *ExpectedPtrType =
+            cast<llvm::PointerType>(IRFuncTy->getParamType(i));
+        unsigned ValueAS = PtrTy->getAddressSpace();
+        unsigned ExpectedAS = ExpectedPtrType->getAddressSpace();
+        if (ValueAS != ExpectedAS) {
+          IRCallArgs[i] = Builder.CreatePointerBitCastOrAddrSpaceCast(
+              IRCallArgs[i], ExpectedPtrType);
+        }
+      }
+    }
+  }
+
   // Assert that the arguments we computed match up.  The IR verifier
   // will catch this, but this is a common enough source of problems
   // during IRGen changes that it's way better for debugging to catch

clang/lib/CodeGen/CGClass.cpp

@@ -316,7 +316,7 @@ Address CodeGenFunction::GetAddressOfBaseClass(
       EmitTypeCheck(TCK_Upcast, Loc, Value.getPointer(),
                     DerivedTy, DerivedAlign, SkippedChecks);
     }
-    return Builder.CreateBitCast(Value, BasePtrTy);
+    return Builder.CreatePointerBitCastOrAddrSpaceCast(Value, BasePtrTy);
   }
 
   llvm::BasicBlock *origBB = nullptr;

clang/lib/CodeGen/CGExpr.cpp

@@ -1089,10 +1089,8 @@ Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
                                       CodeGenFunction::CFITCK_UnrelatedCast,
                                       CE->getBeginLoc());
         }
-        return CE->getCastKind() != CK_AddressSpaceConversion
-                   ? Builder.CreateBitCast(Addr, ConvertType(E->getType()))
-                   : Builder.CreateAddrSpaceCast(Addr,
-                                                 ConvertType(E->getType()));
+        return Builder.CreatePointerBitCastOrAddrSpaceCast(
+            Addr, ConvertType(E->getType()));
       }
       break;
 
@@ -1741,6 +1739,18 @@ void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
     return;
   }
 
+  if (getenv("ENABLE_INFER_AS")) {
+    if (auto *PtrTy = dyn_cast<llvm::PointerType>(Value->getType())) {
+      auto *ExpectedPtrType =
+          cast<llvm::PointerType>(Addr.getType()->getElementType());
+      unsigned ValueAS = PtrTy->getAddressSpace();
+      unsigned ExpectedAS = ExpectedPtrType->getAddressSpace();
+      if (ValueAS != ExpectedAS) {
+        Value =
+            Builder.CreatePointerBitCastOrAddrSpaceCast(Value, ExpectedPtrType);
+      }
+    }
+  }
   llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
   if (isNontemporal) {
     llvm::MDNode *Node =

clang/test/CodeGenSYCL/address-space-new.cpp

@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -triple spir64-unknown-linux-sycldevice  -std=c++11 -fsycl-is-device -disable-llvm-passes -emit-llvm -x c++ %s -o - | FileCheck %s --check-prefix=CHECK-DEFAULT
+// RUN: ENABLE_INFER_AS=1 %clang_cc1 -triple spir64-unknown-linux-sycldevice  -std=c++11 -fsycl-is-device -disable-llvm-passes -emit-llvm -x c++ %s -o - | FileCheck %s --check-prefix=CHECK-NEW
+
+
+void test() {
+  int i = 0;
+  int *pptr = &i;
+  // CHECK-DEFAULT: store i32* %i, i32** %pptr
+  // CHECK-NEW: %[[GEN:[0-9]+]] = addrspacecast i32* %i to i32 addrspace(4)*
+  // CHECK-NEW: store i32 addrspace(4)* %[[GEN]], i32 addrspace(4)** %pptr
+}
+
+
+template <typename name, typename Func>
+__attribute__((sycl_kernel)) void kernel_single_task(Func kernelFunc) {
+  kernelFunc();
+}
+
+
+int main() {
+  kernel_single_task<class fake_kernel>([]() { test(); });
+  return 0;
+}