[clang] [CUDA][HIP] make trivial ctor/dtor host device (PR #72394)

Yaxun Liu via cfe-commits cfe-commits at lists.llvm.org
Wed Nov 15 19:41:55 PST 2023


https://github.com/yxsamliu updated https://github.com/llvm/llvm-project/pull/72394

>From 0efce26340ce058cd2477f5dccbb6ab35cb1c2a0 Mon Sep 17 00:00:00 2001
From: "Yaxun (Sam) Liu" <yaxun.liu at amd.com>
Date: Tue, 14 Nov 2023 22:08:45 -0500
Subject: [PATCH] [CUDA][HIP] make trivial ctor/dtor host device

Make trivial ctor/dtor implicitly host device functions
so that they can be used to initialize file-scope
device variables to match nvcc behavior.

Fixes: https://github.com/llvm/llvm-project/issues/72261

Fixes: SWDEV-432412
---
 clang/include/clang/Sema/Sema.h               |  4 ++
 clang/lib/Sema/SemaCUDA.cpp                   | 16 ++++++++
 clang/lib/Sema/SemaDecl.cpp                   |  3 ++
 .../test/SemaCUDA/call-host-fn-from-device.cu |  2 +-
 clang/test/SemaCUDA/default-ctor.cu           |  2 +-
 .../implicit-member-target-collision-cxx11.cu |  2 +-
 .../implicit-member-target-collision.cu       |  2 +-
 .../implicit-member-target-inherited.cu       |  4 +-
 clang/test/SemaCUDA/implicit-member-target.cu |  4 +-
 clang/test/SemaCUDA/trivial-ctor-dtor.cu      | 40 +++++++++++++++++++
 10 files changed, 71 insertions(+), 8 deletions(-)
 create mode 100644 clang/test/SemaCUDA/trivial-ctor-dtor.cu

diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index a35a3c2c26c22ad..44dcbbf7605a557 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -13450,6 +13450,10 @@ class Sema final {
   void maybeAddCUDAHostDeviceAttrs(FunctionDecl *FD,
                                    const LookupResult &Previous);
 
+  /// May add implicit CUDAHostAttr and CUDADeviceAttr attributes to a
+  /// trivial cotr/dtor that does not have host and device attributes.
+  void maybeAddCUDAHostDeviceAttrsToTrivialCtorDtor(FunctionDecl *FD);
+
   /// May add implicit CUDAConstantAttr attribute to VD, depending on VD
   /// and current compilation settings.
   void MaybeAddCUDAConstantAttr(VarDecl *VD);
diff --git a/clang/lib/Sema/SemaCUDA.cpp b/clang/lib/Sema/SemaCUDA.cpp
index 318174f7be8fa95..b94f448dabe7517 100644
--- a/clang/lib/Sema/SemaCUDA.cpp
+++ b/clang/lib/Sema/SemaCUDA.cpp
@@ -772,6 +772,22 @@ void Sema::maybeAddCUDAHostDeviceAttrs(FunctionDecl *NewD,
   NewD->addAttr(CUDADeviceAttr::CreateImplicit(Context));
 }
 
+// If a trivial ctor/dtor has no host/device
+// attributes, make it implicitly host device function.
+void Sema::maybeAddCUDAHostDeviceAttrsToTrivialCtorDtor(FunctionDecl *FD) {
+  bool IsTrivialCtor = false;
+  if (auto *CD = dyn_cast<CXXConstructorDecl>(FD))
+    IsTrivialCtor = isEmptyCudaConstructor(SourceLocation(), CD);
+  bool IsTrivialDtor = false;
+  if (auto *DD = dyn_cast<CXXDestructorDecl>(FD))
+    IsTrivialDtor = isEmptyCudaDestructor(SourceLocation(), DD);
+  if ((IsTrivialCtor || IsTrivialDtor) && !FD->hasAttr<CUDAHostAttr>() &&
+      !FD->hasAttr<CUDADeviceAttr>()) {
+    FD->addAttr(CUDAHostAttr::CreateImplicit(Context));
+    FD->addAttr(CUDADeviceAttr::CreateImplicit(Context));
+  }
+}
+
 // TODO: `__constant__` memory may be a limited resource for certain targets.
 // A safeguard may be needed at the end of compilation pipeline if
 // `__constant__` memory usage goes beyond limit.
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 3876eb501083acb..a6cd0bb9ea2a829 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -16232,6 +16232,9 @@ Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
   if (FD && !FD->isDeleted())
     checkTypeSupport(FD->getType(), FD->getLocation(), FD);
 
+  if (LangOpts.CUDA)
+    maybeAddCUDAHostDeviceAttrsToTrivialCtorDtor(FD);
+
   return dcl;
 }
 
diff --git a/clang/test/SemaCUDA/call-host-fn-from-device.cu b/clang/test/SemaCUDA/call-host-fn-from-device.cu
index acdd291b664579b..b62de92db02d6de 100644
--- a/clang/test/SemaCUDA/call-host-fn-from-device.cu
+++ b/clang/test/SemaCUDA/call-host-fn-from-device.cu
@@ -12,7 +12,7 @@ extern "C" void host_fn() {}
 struct Dummy {};
 
 struct S {
-  S() {}
+  S() { static int nontrivial_ctor = 1; }
   // expected-note at -1 2 {{'S' declared here}}
   ~S() { host_fn(); }
   // expected-note at -1 {{'~S' declared here}}
diff --git a/clang/test/SemaCUDA/default-ctor.cu b/clang/test/SemaCUDA/default-ctor.cu
index cbad7a1774c1501..31971fe6b3863c7 100644
--- a/clang/test/SemaCUDA/default-ctor.cu
+++ b/clang/test/SemaCUDA/default-ctor.cu
@@ -25,7 +25,7 @@ __device__ void fd() {
   InD ind;
   InH inh; // expected-error{{no matching constructor for initialization of 'InH'}}
   InHD inhd;
-  Out out; // expected-error{{no matching constructor for initialization of 'Out'}}
+  Out out;
   OutD outd;
   OutH outh; // expected-error{{no matching constructor for initialization of 'OutH'}}
   OutHD outhd;
diff --git a/clang/test/SemaCUDA/implicit-member-target-collision-cxx11.cu b/clang/test/SemaCUDA/implicit-member-target-collision-cxx11.cu
index 06015ed0d6d8edc..edb543f637ccc18 100644
--- a/clang/test/SemaCUDA/implicit-member-target-collision-cxx11.cu
+++ b/clang/test/SemaCUDA/implicit-member-target-collision-cxx11.cu
@@ -6,7 +6,7 @@
 // Test 1: collision between two bases
 
 struct A1_with_host_ctor {
-  A1_with_host_ctor() {}
+  A1_with_host_ctor() { static int nontrivial_ctor = 1; }
 };
 
 struct B1_with_device_ctor {
diff --git a/clang/test/SemaCUDA/implicit-member-target-collision.cu b/clang/test/SemaCUDA/implicit-member-target-collision.cu
index a50fddaa4615b22..16b5978af40872b 100644
--- a/clang/test/SemaCUDA/implicit-member-target-collision.cu
+++ b/clang/test/SemaCUDA/implicit-member-target-collision.cu
@@ -6,7 +6,7 @@
 // Test 1: collision between two bases
 
 struct A1_with_host_ctor {
-  A1_with_host_ctor() {}
+  A1_with_host_ctor() { static int nontrivial_ctor = 1; }
 };
 
 struct B1_with_device_ctor {
diff --git a/clang/test/SemaCUDA/implicit-member-target-inherited.cu b/clang/test/SemaCUDA/implicit-member-target-inherited.cu
index 2178172ed01930d..781199bba6b5a11 100644
--- a/clang/test/SemaCUDA/implicit-member-target-inherited.cu
+++ b/clang/test/SemaCUDA/implicit-member-target-inherited.cu
@@ -6,7 +6,7 @@
 // Test 1: infer inherited default ctor to be host.
 
 struct A1_with_host_ctor {
-  A1_with_host_ctor() {}
+  A1_with_host_ctor() { static int nontrivial_ctor = 1; }
 };
 // expected-note at -3 {{candidate constructor (the implicit copy constructor) not viable}}
 // expected-note at -4 {{candidate constructor (the implicit move constructor) not viable}}
@@ -83,7 +83,7 @@ void hostfoo3() {
 // Test 4: infer inherited default ctor from a field, not a base
 
 struct A4_with_host_ctor {
-  A4_with_host_ctor() {}
+  A4_with_host_ctor() { static int nontrivial_ctor = 1; }
 };
 
 struct B4_with_inherited_host_ctor : A4_with_host_ctor{
diff --git a/clang/test/SemaCUDA/implicit-member-target.cu b/clang/test/SemaCUDA/implicit-member-target.cu
index d87e69624043419..552f8f2ebd94fd5 100644
--- a/clang/test/SemaCUDA/implicit-member-target.cu
+++ b/clang/test/SemaCUDA/implicit-member-target.cu
@@ -6,7 +6,7 @@
 // Test 1: infer default ctor to be host.
 
 struct A1_with_host_ctor {
-  A1_with_host_ctor() {}
+  A1_with_host_ctor() { static int nontrivial_ctor = 1; }
 };
 
 // The implicit default constructor is inferred to be host because it only needs
@@ -75,7 +75,7 @@ void hostfoo3() {
 // Test 4: infer default ctor from a field, not a base
 
 struct A4_with_host_ctor {
-  A4_with_host_ctor() {}
+  A4_with_host_ctor() { static int nontrivial_ctor = 1; }
 };
 
 struct B4_with_implicit_default_ctor {
diff --git a/clang/test/SemaCUDA/trivial-ctor-dtor.cu b/clang/test/SemaCUDA/trivial-ctor-dtor.cu
new file mode 100644
index 000000000000000..1df8adc62bab590
--- /dev/null
+++ b/clang/test/SemaCUDA/trivial-ctor-dtor.cu
@@ -0,0 +1,40 @@
+// RUN: %clang_cc1 -isystem %S/Inputs  -fsyntax-only -verify %s
+// RUN: %clang_cc1 -isystem %S/Inputs -fcuda-is-device -fsyntax-only -verify %s
+
+#include <cuda.h>
+
+// Check trivial ctor/dtor
+struct A {
+  int x;
+  A() {}
+  ~A() {}
+};
+
+__device__ A a;
+
+// Check trivial ctor/dtor of template class
+template<typename T>
+struct TA {
+  T x;
+  TA() {}
+  ~TA() {}
+};
+
+__device__ TA<int> ta;
+
+// Check non-trivial ctor/dtor in parent template class
+template<typename T>
+struct TB {
+  T x;
+  TB() { static int nontrivial_ctor = 1; }
+  ~TB() {}
+};
+
+template<typename T>
+struct TC : TB<T> {
+  T x;
+  TC() {}
+  ~TC() {}
+};
+
+__device__ TC<int> tc; //expected-error {{dynamic initialization is not supported for __device__, __constant__, __shared__, and __managed__ variables}}



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