CUDA target attributes are used for function overloading and must not be merged.
This fixes a bug where attributes were inherited during function template
specialization in CUDA and made it impossible for specialized function
to provide its own target attributes.
Differential Revision: https://reviews.llvm.org/D24522
llvm-svn: 281406
NewAttr = S.mergeAlwaysInlineAttr(D, AA->getRange(),
&S.Context.Idents.get(AA->getSpelling()),
AttrSpellingListIndex);
- else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
+ else if (S.getLangOpts().CUDA && isa<FunctionDecl>(D) &&
+ (isa<CUDAHostAttr>(Attr) || isa<CUDADeviceAttr>(Attr) ||
+ isa<CUDAGlobalAttr>(Attr))) {
+ // CUDA target attributes are part of function signature for
+ // overloading purposes and must not be merged.
+ return false;
+ } else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
NewAttr = S.mergeMinSizeAttr(D, MA->getRange(), AttrSpellingListIndex);
else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr))
NewAttr = S.mergeOptimizeNoneAttr(D, OA->getRange(), AttrSpellingListIndex);
HostReturnTy ret3 = host_only_function(1);
HostReturnTy2 ret4 = host_only_function(1.0f);
}
+
+// Verify that we allow overloading function templates.
+template <typename T> __host__ T template_overload(const T &a) { return a; };
+template <typename T> __device__ T template_overload(const T &a) { return a; };
+
+__host__ void test_host_template_overload() {
+ template_overload(1); // OK. Attribute-based overloading picks __host__ variant.
+}
+__device__ void test_device_template_overload() {
+ template_overload(1); // OK. Attribute-based overloading picks __device__ variant.
+}
--- /dev/null
+// Verifies correct inheritance of target attributes during template
+// instantiation and specialization.
+
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple nvptx64-nvidia-cuda -fsyntax-only -fcuda-is-device -verify %s
+
+#include "Inputs/cuda.h"
+
+// Function must inherit target attributes during instantiation, but not during
+// specialization.
+template <typename T> __host__ __device__ T function_template(const T &a);
+
+// Specialized functions have their own attributes.
+// expected-note@+1 {{candidate function not viable: call to __host__ function from __device__ function}}
+template <> __host__ float function_template<float>(const float &from);
+
+// expected-note@+1 {{candidate function not viable: call to __device__ function from __host__ function}}
+template <> __device__ double function_template<double>(const double &from);
+
+__host__ void hf() {
+ function_template<float>(1.0f); // OK. Specialization is __host__.
+ function_template<double>(2.0); // expected-error {{no matching function for call to 'function_template'}}
+ function_template(1); // OK. Instantiated function template is HD.
+}
+__device__ void df() {
+ function_template<float>(3.0f); // expected-error {{no matching function for call to 'function_template'}}
+ function_template<double>(4.0); // OK. Specialization is __device__.
+ function_template(1); // OK. Instantiated function template is HD.
+}