Fix 32-bit long size check

Originally I changed the isOsWindows check to isWindowsMSVCEnvironment,
but neither of those is correct. The correct check is isOsWindows &&
!isWindowsCygwinEnvironment, because all known Windows environments
except Cygwin use 32-bit long.
I think we don't support SYCL on MinGW or Cygwin, but this is one less
bug to fix if we ever decide to.

Author: Maetveis

clang/lib/Driver/ToolChains/SYCL.cpp

@@ -152,8 +152,12 @@ SYCLInstallationDetector::SYCLInstallationDetector(
 static llvm::SmallString<64>
 getLibSpirvBasename(const llvm::Triple &DeviceTriple,
                     const llvm::Triple &HostTriple) {
-  // Select remangled libclc variant
-  llvm::SmallString<64> Result(HostTriple.isWindowsMSVCEnvironment()
+  // Select remangled libclc variant.
+  // Decide long size based on host triple, because offloading targets are going
+  // to match that.
+  // All known windows environments except Cygwin use 32-bit long.
+  llvm::SmallString<64> Result(HostTriple.isOSWindows() &&
+                                       !HostTriple.isWindowsCygwinEnvironment()
                                    ? "remangled-l32-signed_char.libspirv-"
                                    : "remangled-l64-signed_char.libspirv-");
 

clang/test/Driver/sycl-libspirv-toolchain.cpp

@@ -5,10 +5,14 @@
 
 // RUN: %clang -### -fsycl -fsycl-targets=nvptx64-nvidia-cuda -nocudalib -target x86_64-unknown-windows-msvc %s 2>&1 \
 // RUN: | FileCheck %s --check-prefixes=CHECK-WINDOWS
+// RUN: %clang -### -fsycl -fsycl-targets=nvptx64-nvidia-cuda -nocudalib -target x86_64-unknown-windows-gnu %s 2>&1 \
+// RUN: | FileCheck %s --check-prefixes=CHECK-WINDOWS
 // CHECK-WINDOWS: "-cc1"{{.*}} "-fsycl-is-device"{{.*}} "-mlink-builtin-bitcode" "{{.*[\\/]}}remangled-l32-signed_char.libspirv-nvptx64-nvidia-cuda.bc"
 //
 // RUN: %clang -### -fsycl -fsycl-targets=nvptx64-nvidia-cuda -nocudalib -target x86_64-unknown-linux-gnu %s 2>&1 \
 // RUN: | FileCheck %s --check-prefixes=CHECK-LINUX
+// RUN: %clang -### -fsycl -fsycl-targets=nvptx64-nvidia-cuda -nocudalib -target x86_64-unknown-windows-cygnus %s 2>&1 \
+// RUN: | FileCheck %s --check-prefixes=CHECK-LINUX
 // CHECK-LINUX: "-cc1"{{.*}} "-fsycl-is-device"{{.*}} "-mlink-builtin-bitcode" "{{.*[\\/]}}remangled-l64-signed_char.libspirv-nvptx64-nvidia-cuda.bc"
 //
 // RUN: %clang -### -resource-dir %{resource_dir} -fsycl -fsycl-targets=amdgcn-amd-amdhsa -Xsycl-target-backend --offload-arch=gfx908 -nogpulib -target x86_64-unknown-windows-msvc %s 2>&1 \