tra updated this revision to Diff 44687.
tra added a comment.
Check all variable initializers and only allow 'empty constructors' as Richard
has suggested.
Changed test structure so that we test for allowed/disallowed constructors
separately from testing how we handle initialization of base classes or member
fields.
http://reviews.llvm.org/D15305
Files:
lib/CodeGen/CGDeclCXX.cpp
lib/CodeGen/CodeGenModule.cpp
lib/CodeGen/CodeGenModule.h
test/CodeGenCUDA/device-var-init.cu
Index: test/CodeGenCUDA/device-var-init.cu
===================================================================
--- /dev/null
+++ test/CodeGenCUDA/device-var-init.cu
@@ -0,0 +1,364 @@
+// REQUIRES: nvptx-registered-target
+
+// Make sure we don't allow dynamic initialization for device
+// variables, but accept empty constructors allowed by CUDA.
+
+// RUN: %clang_cc1 -triple nvptx64-nvidia-cuda -fcuda-is-device -std=c++11 \
+// RUN: -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple nvptx64-nvidia-cuda -fcuda-is-device -std=c++11 \
+// RUN: -emit-llvm -DERROR_CASE -verify -o /dev/null %s
+
+#ifdef __clang__
+#include "Inputs/cuda.h"
+#endif
+
+// Base classes with different initializer variants.
+
+// trivial constructor -- allowed
+struct T {
+ int t;
+};
+
+// empty constructor
+struct EC {
+ int ec;
+ __device__ EC() {} // -- allowed
+ __device__ EC(int) {} // -- not allowed
+};
+
+// empty templated constructor -- allowed with no arguments
+struct ETC {
+ template <typename... T> __device__ ETC(T...) {}
+};
+
+// undefined constructor -- not allowed
+struct UC {
+ int uc;
+ __device__ UC();
+};
+
+// empty constructor w/ initializer list -- not allowed
+struct ECI {
+ int eci;
+ __device__ ECI() : eci(1) {}
+};
+
+// non-empty constructor -- not allowed
+struct NEC {
+ int nec;
+ __device__ NEC() { nec = 1; }
+};
+
+// no-constructor, virtual method -- not allowed
+struct NCV {
+ int ncv;
+ __device__ virtual void vm() {}
+};
+
+// dynamic in-class field initializer -- not allowed
+__device__ int f();
+struct NCF {
+ int ncf = f();
+};
+
+// static in-class field initializer -- not allowed by nvcc.
+// NOTE: clang does generate statically initalized field here.
+// So in practice it could be supported.
+struct NCFS {
+ int ncfs = 3;
+};
+
+// undefined templated constructor -- not allowed
+struct UTC {
+ template <typename... T> __device__ UTC(T...);
+};
+
+// non-empty templated constructor -- not allowed
+struct NETC {
+ int netc;
+ template <typename... T> __device__ NETC(T...) { netc = 1; }
+};
+
+__device__ T d_t;
+// CHECK: @d_t = addrspace(1) externally_initialized global %struct.T zeroinitializer
+__shared__ T s_t;
+// CHECK: @s_t = addrspace(3) global %struct.T undef,
+__constant__ T c_t;
+// CHECK: @c_t = addrspace(4) externally_initialized global %struct.T zeroinitializer,
+
+__device__ T d_t_i = {2};
+// CHECKL @d_t_i = addrspace(1) externally_initialized global %struct.T { i32 2 },
+#ifdef ERROR_CASE
+__shared__ T s_t_i = {2};
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+#endif
+__constant__ T c_t_i = {2};
+// CHECK: @c_t_i = addrspace(4) externally_initialized global %struct.T { i32 2 },
+
+__device__ EC d_ec;
+// CHECK: @d_ec = addrspace(1) externally_initialized global %struct.EC zeroinitializer,
+__shared__ EC s_ec;
+// CHECK: @s_ec = addrspace(3) global %struct.EC undef,
+__constant__ EC c_ec;
+// CHECK: @c_ec = addrspace(4) externally_initialized global %struct.EC zeroinitializer,
+
+#if ERROR_CASE
+__device__ EC d_ec_i(3);
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ EC s_ec_i(3);
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ EC c_ec_i(3);
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ EC d_ec_i2 = {3};
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ EC s_ec_i2 = {3};
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ EC c_ec_i2 = {3};
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+#endif
+
+__device__ ETC d_etc;
+// CHETCK: @d_etc = addrspace(1) externally_initialized global %struct.ETC zeroinitializer,
+__shared__ ETC s_etc;
+// CHETCK: @s_etc = addrspace(3) global %struct.ETC undef,
+__constant__ ETC c_etc;
+// CHETCK: @c_etc = addrspace(4) externally_initialized global %struct.ETC zeroinitializer,
+
+#if ERROR_CASE
+__device__ ETC d_etc_i(3);
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ ETC s_etc_i(3);
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ ETC c_etc_i(3);
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ ETC d_etc_i2 = {3};
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ ETC s_etc_i2 = {3};
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ ETC c_etc_i2 = {3};
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ UC d_uc;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ UC s_uc;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ UC c_uc;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ ECI d_eci;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ ECI s_eci;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ ECI c_eci;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ NEC d_nec;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ NEC s_nec;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ NEC c_nec;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ NCV d_ncv;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ NCV s_ncv;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ NCV c_ncv;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ NCF d_ncf;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ NCF s_ncf;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ NCF c_ncf;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ NCFS d_ncfs;
+// NO_expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ NCFS s_ncfs;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ NCFS c_ncfs;
+// NO_expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ UTC d_utc;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ UTC s_utc;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ UTC c_utc;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ UTC d_utc_i(3);
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ UTC s_utc_i(3);
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ UTC c_utc_i(3);
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ NETC d_netc;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ NETC s_netc;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ NETC c_netc;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ NETC d_netc_i(3);
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ NETC s_netc_i(3);
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ NETC c_netc_i(3);
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+#endif
+
+// Regular base class -- allowed
+struct T_B_T : T {};
+__device__ T_B_T d_t_b_t;
+// CHECK: @d_t_b_t = addrspace(1) externally_initialized global %struct.T_B_T zeroinitializer,
+__shared__ T_B_T s_t_b_t;
+// CHECK: @s_t_b_t = addrspace(3) global %struct.T_B_T undef,
+__constant__ T_B_T c_t_b_t;
+// CHECK: @c_t_b_t = addrspace(4) externally_initialized global %struct.T_B_T zeroinitializer,
+
+// Incapsulated object of allowed class -- allowed
+struct T_F_T {
+ T t;
+};
+__device__ T_F_T d_t_f_t;
+// CHECK: @d_t_f_t = addrspace(1) externally_initialized global %struct.T_F_T zeroinitializer,
+__shared__ T_F_T s_t_f_t;
+// CHECK: @s_t_f_t = addrspace(3) global %struct.T_F_T undef,
+__constant__ T_F_T c_t_f_t;
+// CHECK: @c_t_f_t = addrspace(4) externally_initialized global %struct.T_F_T zeroinitializer,
+
+// array of allowed objects -- allowed
+struct T_FA_T {
+ T t[2];
+};
+__device__ T_FA_T d_t_fa_t;
+// CHECK: @d_t_fa_t = addrspace(1) externally_initialized global %struct.T_FA_T zeroinitializer,
+__shared__ T_FA_T s_t_fa_t;
+// CHECK: @s_t_fa_t = addrspace(3) global %struct.T_FA_T undef,
+__constant__ T_FA_T c_t_fa_t;
+// CHECK: @c_t_fa_t = addrspace(4) externally_initialized global %struct.T_FA_T zeroinitializer,
+
+
+// Calling empty base class initializer is OK
+struct EC_I_EC : EC {
+ __device__ EC_I_EC() : EC() {}
+};
+__device__ EC_I_EC d_ec_i_ec;
+// CHECK: @d_ec_i_ec = addrspace(1) externally_initialized global %struct.EC_I_EC zeroinitializer,
+__shared__ EC_I_EC s_ec_i_ec;
+// CHECK: @s_ec_i_ec = addrspace(3) global %struct.EC_I_EC undef,
+__constant__ EC_I_EC c_ec_i_ec;
+// CHECK: @c_ec_i_ec = addrspace(4) externally_initialized global %struct.EC_I_EC zeroinitializer,
+
+// .. though passing arguments is not allowed.
+struct EC_I_EC1 : EC {
+ __device__ EC_I_EC1() : EC(1) {}
+};
+#if ERROR_CASE
+__device__ EC_I_EC1 d_ec_i_ec1;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ EC_I_EC1 s_ec_i_ec1;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ EC_I_EC1 c_ec_i_ec1;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+#endif
+
+// Virtual base class -- not allowed
+struct T_V_T : virtual T {};
+#if ERROR_CASE
+__device__ T_V_T d_t_v_t;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ T_V_T s_t_v_t;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ T_V_T c_t_v_t;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+#endif
+
+// Make sure that we don't allow if we inherit or incapsulate
+// something with disallowed initializer.
+
+// Inherited from or incapsulated class with non-empty constructor --
+// not allowed
+struct T_B_NEC : NEC {};
+struct T_F_NEC {
+ NEC nec;
+};
+struct T_FA_NEC {
+ NEC nec[2];
+};
+
+#if ERROR_CASE
+__device__ T_B_NEC d_t_b_nec;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ T_B_NEC s_t_b_nec;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ T_B_NEC c_t_b_nec;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ T_F_NEC d_t_f_nec;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ T_F_NEC s_t_f_nec;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ T_F_NEC c_t_f_nec;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+
+__device__ T_FA_NEC d_t_fa_nec;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+__shared__ T_FA_NEC s_t_fa_nec;
+// expected-error@-1 {{initialization is not supported for __shared__ variables.}}
+__constant__ T_FA_NEC c_t_fa_nec;
+// expected-error@-1 {{dynamic initialization is not supported for __device__, __constant__ and __shared__ variables.}}
+#endif
+
+// We should not emit global initializers for device-side variables.
+// CHECK-NOT: @__cxx_global_var_init
+
+// Make sure that initialization restrictions do not apply to local
+// variables.
+__device__ void df() {
+ T t;
+ EC ec;
+ ETC etc;
+ UC uc;
+ ECI eci;
+ NEC nec;
+ NCV ncv;
+ NCF ncf;
+ NCFS ncfs;
+ UTC utc;
+ NETC netc;
+ T_B_T t_b_t;
+ T_F_T t_f_t;
+ T_FA_T t_fa_t;
+ EC_I_EC ec_i_ec;
+ EC_I_EC1 ec_i_ec1;
+ T_V_T t_v_t;
+ T_B_NEC t_b_nec;
+ T_F_NEC t_f_nec;
+ T_FA_NEC t_fa_nec;
+}
+
+// CHECK: call void @_ZN2ECC1Ev(%struct.EC* %ec)
+// CHECK: call void @_ZN3ETCC1IJEEEDpT_(%struct.ETC* %etc)
+// CHECK: call void @_ZN2UCC1Ev(%struct.UC* %uc)
+// CHECK: call void @_ZN3ECIC1Ev(%struct.ECI* %eci)
+// CHECK: call void @_ZN3NECC1Ev(%struct.NEC* %nec)
+// CHECK: call void @_ZN3NCVC1Ev(%struct.NCV* %ncv) #3
+// CHECK: call void @_ZN3NCFC1Ev(%struct.NCF* %ncf)
+// CHECK: call void @_ZN4NCFSC1Ev(%struct.NCFS* %ncfs) #3
+// CHECK: call void @_ZN3UTCC1IJEEEDpT_(%struct.UTC* %utc)
+// CHECK: call void @_ZN4NETCC1IJEEEDpT_(%struct.NETC* %netc)
+// CHECK: call void @_ZN7EC_I_ECC1Ev(%struct.EC_I_EC* %ec_i_ec)
+// CHECK: call void @_ZN8EC_I_EC1C1Ev(%struct.EC_I_EC1* %ec_i_ec1)
+// CHECK: call void @_ZN5T_V_TC1Ev(%struct.T_V_T* %t_v_t) #3
+// CHECK: call void @_ZN7T_B_NECC1Ev(%struct.T_B_NEC* %t_b_nec)
+// CHECK: call void @_ZN7T_F_NECC1Ev(%struct.T_F_NEC* %t_f_nec)
+// CHECK: call void @_ZN8T_FA_NECC1Ev(%struct.T_FA_NEC* %t_fa_nec)
+// CHECK: ret void
+
+// We should not emit global init function.
+// CHECK-NOT: @_GLOBAL__sub_I
Index: lib/CodeGen/CodeGenModule.h
===================================================================
--- lib/CodeGen/CodeGenModule.h
+++ lib/CodeGen/CodeGenModule.h
@@ -1126,6 +1126,10 @@
/// \breif Get the declaration of std::terminate for the platform.
llvm::Constant *getTerminateFn();
+ /// Returns whether given CXXConstructorDecl is an empty constructor
+ /// allowed by CUDA (E2.2.1, CUDA 7.5).
+ bool isEmptyCudaConstructor(const CXXConstructorDecl *CD);
+
private:
llvm::Constant *
GetOrCreateLLVMFunction(StringRef MangledName, llvm::Type *Ty, GlobalDecl D,
Index: lib/CodeGen/CodeGenModule.cpp
===================================================================
--- lib/CodeGen/CodeGenModule.cpp
+++ lib/CodeGen/CodeGenModule.cpp
@@ -1417,6 +1417,11 @@
if (LangOpts.OpenMP && LangOpts.OpenMPUseTLS &&
getContext().getTargetInfo().isTLSSupported() && isa<VarDecl>(Global))
return false;
+ // Delay codegen for device-side CUDA variables. We need to have all
+ // constructor definitions available before we can determine whether
+ // we can skip them or produce an error.
+ if (LangOpts.CUDA && LangOpts.CUDAIsDevice && isa<VarDecl>(Global))
+ return false;
return true;
}
@@ -2275,9 +2280,9 @@
&& D->hasAttr<CUDASharedAttr>()) {
if (InitExpr) {
const auto *C = dyn_cast<CXXConstructExpr>(InitExpr);
- if (C == nullptr || !C->getConstructor()->hasTrivialBody())
- Error(D->getLocation(),
- "__shared__ variable cannot have an initialization.");
+ if (C == nullptr || !isEmptyCudaConstructor(C->getConstructor()))
+ Error(D->getLocation(), "initialization is not supported for "
+ "__shared__ variables.");
}
Init = llvm::UndefValue::get(getTypes().ConvertType(ASTTy));
} else if (!InitExpr) {
Index: lib/CodeGen/CGDeclCXX.cpp
===================================================================
--- lib/CodeGen/CGDeclCXX.cpp
+++ lib/CodeGen/CGDeclCXX.cpp
@@ -300,10 +300,67 @@
PtrArray->setComdat(C);
}
+bool CodeGenModule::isEmptyCudaConstructor(const CXXConstructorDecl *CD) {
+ // (E.2.3.1, CUDA 7.5) A constructor for a class type is considered
+ // empty at a point in the translation unit, if it is either a
+ // trivial constructor
+ if (CD->isTrivial())
+ return true;
+
+ // ... or it satisfies all of the following conditions:
+ // The constructor function has been defined.
+ // The constructor function has no parameters,
+ // and the function body is an empty compound statement.
+ if (!(CD->isDefined() && CD->getNumParams() == 0 && CD->hasTrivialBody()))
+ return false;
+
+ // The only form of initializer allowed is an empty constructor.
+ // This will recursively checks all base classes and member initializers
+ if (!std::all_of(CD->init_begin(), CD->init_end(),
+ [&](const CXXCtorInitializer *CI) {
+ if (const CXXConstructExpr *CE =
+ dyn_cast<CXXConstructExpr>(CI->getInit()))
+ return isEmptyCudaConstructor(CE->getConstructor());
+ return false;
+ }))
+ return false;
+
+ const CXXRecordDecl *RD = CD->getParent();
+ // Its class has no virtual functions
+ if (std::any_of(
+ RD->method_begin(), RD->method_end(),
+ [](const CXXMethodDecl *Method) { return Method->isVirtual(); }))
+ return false;
+
+ // .. and no virtual base classes.
+ if (RD->getNumVBases() != 0)
+ return false;
+
+ return true;
+}
+
void
CodeGenModule::EmitCXXGlobalVarDeclInitFunc(const VarDecl *D,
llvm::GlobalVariable *Addr,
bool PerformInit) {
+
+ // According to E.2.3.1 in CUDA-7.5 Programming guide:
+ // __device__, __constant__ and __shared__ variables defined in
+ // namespace scope, that are of class type, cannot have a non-empty
+ // constructor...
+ if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice &&
+ (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>() ||
+ D->hasAttr<CUDASharedAttr>())) {
+ if (const Expr *InitExpr = D->getAnyInitializer()) {
+ const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(InitExpr);
+ if (CE == nullptr || !isEmptyCudaConstructor(CE->getConstructor()))
+ Error(D->getLocation(), "dynamic initialization is not supported for "
+ "__device__, __constant__ and __shared__ "
+ "variables.");
+ }
+ return;
+ }
+
// Check if we've already initialized this decl.
auto I = DelayedCXXInitPosition.find(D);
if (I != DelayedCXXInitPosition.end() && I->second == ~0U)
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
