r361994 - [CUDA][HIP] Skip setting `externally_initialized` for static device variables.

[Michael Liao via cfe-commits]

Author: hliao
Date: Wed May 29 10:23:27 2019
New Revision: 361994

URL: http://llvm.org/viewvc/llvm-project?rev=361994&view=rev
Log:
[CUDA][HIP] Skip setting `externally_initialized` for static device variables.

Summary:
- By declaring device variables as `static`, we assume they won't be
  addressable from the host side. Thus, no `externally_initialized` is
  required.

Reviewers: yaxunl

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62603

Modified:
    cfe/trunk/lib/CodeGen/CodeGenModule.cpp
    cfe/trunk/test/CodeGenCUDA/device-var-init.cu

Modified: cfe/trunk/lib/CodeGen/CodeGenModule.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.cpp?rev=361994&r1=361993&r2=361994&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenModule.cpp Wed May 29 10:23:27 2019
@@ -3869,7 +3869,8 @@ void CodeGenModule::EmitGlobalVarDefinit
   // / cudaMemcpyToSymbol() / cudaMemcpyFromSymbol())."
   if (GV && LangOpts.CUDA) {
     if (LangOpts.CUDAIsDevice) {
-      if (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>())
+      if (Linkage != llvm::GlobalValue::InternalLinkage &&
+          (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>()))
         GV->setExternallyInitialized(true);
     } else {
       // Host-side shadows of external declarations of device-side

Modified: cfe/trunk/test/CodeGenCUDA/device-var-init.cu
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCUDA/device-var-init.cu?rev=361994&r1=361993&r2=361994&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCUDA/device-var-init.cu (original)
+++ cfe/trunk/test/CodeGenCUDA/device-var-init.cu Wed May 29 10:23:27 2019
@@ -33,6 +33,16 @@ __device__ int d_v_i = 1;
 // DEVICE: @d_v_i = addrspace(1) externally_initialized global i32 1,
 // HOST:   @d_v_i = internal global i32 undef,
 
+// For `static` device variables, assume they won't be addressed from the host
+// side.
+static __device__ int d_s_v_i = 1;
+// DEVICE: @_ZL7d_s_v_i = internal addrspace(1) global i32 1,
+
+// Dummy function to keep static variables referenced.
+__device__ int foo() {
+  return d_s_v_i;
+}
+
 // trivial constructor -- allowed
 __device__ T d_t;
 // DEVICE: @d_t = addrspace(1) externally_initialized global %struct.T zeroinitializer