From d8e0ae9a76a62bdc6117630d59bf9967ac9bb4ea Mon Sep 17 00:00:00 2001
From: Erich Keane <erich.keane@intel.com>
Date: Wed, 2 Jun 2021 12:50:52 -0700
Subject: [PATCH] [SYCL] Fix __builtin_sycl_unique_stable_name to work on
 windows/spir

In the case where the device is an itanium target, and the host is a
windows target, we were getting the names wrong, since in the itanium
case we filter by lambda-signature.

The fix is to always filter by the signature rather than just on
non-windows builds. I considered doing the reverse (that is, checking
the aux-triple), but doing so would result in duplicate lambda mangling
numbers (from linux reusing the same number for different signatures).
---
 clang/lib/AST/ASTContext.cpp                  |  7 +--
 .../unique_stable_name_windows_diff.cpp       | 44 +++++++++++++++++++
 2 files changed, 45 insertions(+), 6 deletions(-)
 create mode 100644 clang/test/CodeGenSYCL/unique_stable_name_windows_diff.cpp

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index e96f52920521..76f84c728bc6 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -11750,12 +11750,7 @@ unsigned ASTContext::GetSYCLKernelNamingIndex(const NamedDecl *ND) {
 
   llvm::SmallVector<const CXXRecordDecl *> Decls{Set.begin(), Set.end()};
 
-  // If we are in an itanium situation, the mangling-numbers for a lambda depend
-  // on the mangled signature, so sort by that. Only TargetCXXABI::Microsoft
-  // doesn't use the itanium mangler, and just sets the lambda mangling number
-  // incrementally, with no consideration to the signature.
-  if (Target->getCXXABI().getKind() != TargetCXXABI::Microsoft)
-    FilterSYCLKernelNamingDecls(RD, Decls);
+  FilterSYCLKernelNamingDecls(RD, Decls);
 
   llvm::sort(Decls, [](const CXXRecordDecl *LHS, const CXXRecordDecl *RHS) {
     return LHS->getLambdaManglingNumber() < RHS->getLambdaManglingNumber();
diff --git a/clang/test/CodeGenSYCL/unique_stable_name_windows_diff.cpp b/clang/test/CodeGenSYCL/unique_stable_name_windows_diff.cpp
new file mode 100644
index 000000000000..ecdc1d50abbe
--- /dev/null
+++ b/clang/test/CodeGenSYCL/unique_stable_name_windows_diff.cpp
@@ -0,0 +1,44 @@
+// RUN: %clang_cc1 -triple spir64-unknown-unknown-sycldevice -aux-triple x86_64-pc-windows-msvc -fsycl-is-device -disable-llvm-passes -fsycl-is-device -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-pc-windows-msvc -fsycl-is-device -disable-llvm-passes -fsycl-is-device -emit-llvm %s -o - | FileCheck %s
+
+
+template<typename KN, typename Func>
+__attribute__((sycl_kernel)) void kernel(Func F){
+  F();
+}
+
+template<typename KN, typename Func>
+__attribute__((sycl_kernel)) void kernel2(Func F){
+  F(1);
+}
+
+template<typename KN, typename Func>
+__attribute__((sycl_kernel)) void kernel3(Func F){
+  F(1.1);
+}
+
+int main() {
+  int i;
+  double d;
+  float f;
+  auto lambda1 = [](){};
+  auto lambda2 = [](int){};
+  auto lambda3 = [](double){};
+
+  kernel<class K1>(lambda1);
+  kernel2<class K2>(lambda2);
+  kernel3<class K3>(lambda3);
+
+  // Ensure the kernels are named the same between the device and host
+  // invocations.
+  (void)__builtin_sycl_unique_stable_name(decltype(lambda1));
+  (void)__builtin_sycl_unique_stable_name(decltype(lambda2));
+  (void)__builtin_sycl_unique_stable_name(decltype(lambda3));
+
+  // Make sure the following 3 are the same between the host and device compile.
+  // Note that these are NOT the same value as eachother, they differ by the
+  // signature.
+  // CHECK: private unnamed_addr constant [22 x i8] c"_ZTSZ4mainEUlvE10000_\00"
+  // CHECK: private unnamed_addr constant [22 x i8] c"_ZTSZ4mainEUliE10000_\00"
+  // CHECK: private unnamed_addr constant [22 x i8] c"_ZTSZ4mainEUldE10000_\00"
+}