diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -9569,7 +9569,8 @@
     }
   }
 
-  if (LangOpts.SYCLIsDevice || (LangOpts.OpenMP && LangOpts.OpenMPIsDevice))
+  if (LangOpts.SYCLIsDevice || (LangOpts.OpenMP && LangOpts.OpenMPIsDevice) ||
+      LangOpts.CUDAIsDevice)
     checkDeviceDecl(NewFD, D.getBeginLoc());
 
   if (!getLangOpts().CPlusPlus) {
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -366,7 +366,8 @@
 
   diagnoseUseOfInternalDeclInInlineFunction(*this, D, Loc);
 
-  if (LangOpts.SYCLIsDevice || (LangOpts.OpenMP && LangOpts.OpenMPIsDevice)) {
+  if (LangOpts.SYCLIsDevice || (LangOpts.OpenMP && LangOpts.OpenMPIsDevice) ||
+      LangOpts.CUDAIsDevice) {
     if (auto *VD = dyn_cast<ValueDecl>(D))
       checkDeviceDecl(VD, Loc);
 
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -1496,7 +1496,7 @@
   }
   case DeclSpec::TST_int128:
     if (!S.Context.getTargetInfo().hasInt128Type() &&
-        !S.getLangOpts().SYCLIsDevice &&
+        !S.getLangOpts().SYCLIsDevice && !S.getLangOpts().CUDAIsDevice &&
         !(S.getLangOpts().OpenMP && S.getLangOpts().OpenMPIsDevice))
       S.Diag(DS.getTypeSpecTypeLoc(), diag::err_type_unsupported)
         << "__int128";
diff --git a/clang/test/SemaCUDA/allow-int128.cu b/clang/test/SemaCUDA/allow-int128.cu
new file mode 100644
--- /dev/null
+++ b/clang/test/SemaCUDA/allow-int128.cu
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa \
+// RUN:   -aux-triple x86_64-unknown-linux-gnu \
+// RUN:   -fcuda-is-device -verify -fsyntax-only %s
+// RUN: %clang_cc1 -triple nvptx \
+// RUN:   -aux-triple x86_64-unknown-linux-gnu \
+// RUN:   -fcuda-is-device -verify -fsyntax-only %s
+
+// expected-no-diagnostics
+#define __device__ __attribute__((device))
+
+__int128 h_glb;
+__device__ __int128 d_unused;
+__device__ __int128 d_glb;
+__device__ __int128 bar() {
+  return d_glb;
+}
diff --git a/clang/test/SemaCUDA/spirv-int128.cu b/clang/test/SemaCUDA/spirv-int128.cu
new file mode 100644
--- /dev/null
+++ b/clang/test/SemaCUDA/spirv-int128.cu
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -triple spirv64 -aux-triple x86_64-unknown-linux-gnu \
+// RUN:   -fcuda-is-device -verify -fsyntax-only %s
+
+#define __device__ __attribute__((device))
+
+__int128 h_glb;
+
+__device__ __int128 d_unused;
+
+// expected-note@+1 {{'d_glb' defined here}}
+__device__ __int128 d_glb;
+
+__device__ __int128 bar() {
+  // expected-error@+1 {{'d_glb' requires 128 bit size '__int128' type support, but device 'spirv64' does not support it}}
+  return d_glb;
+}