[Clang] Link ITT libraries in device code by default (#16094)

Fixes: CMPLRLLVM-63157

**Problem**
Consider the following case:
```
clang++ -fsycl -c testFile.cpp -o obj1.o
clang++ -fsycl -c testFile2.cpp -o obj2.o -fsycl-instrument-device-code
clang++ -fsycl obj1.o obj2.o -o test.exe

// test.exe fails with:
JIT session error: Symbols not found: [ __itt_offload_wi_finish_wrapper, __itt_offload_wi_start_wrapper ]
```
This issue was observed while using MKL static libraries built with
`-fsycl-instrument-device-code` with the latest compiler that does not
link ITT annotations by default.

With this change, we link in ITT libraries by default to stays ABI
compliant with the previous release. During device code linking, if the
device code is not instrumented with ITT annotations, this library will
be omitted. Note that, even with this change, we are not instrumenting
device code with ITT annotations by default.

clang/lib/Driver/ToolChains/SYCL.cpp

@@ -650,8 +650,11 @@ SYCL::getDeviceLibraries(const Compilation &C, const llvm::Triple &TargetTriple,
       addLibraries(SYCLDeviceBfloat16FallbackLib);
   }
 
+  // Link in ITT annotations library unless fsycl-no-instrument-device-code
+  // is specified. This ensures that we are ABI-compatible with the
+  // instrumented device code, which was the default not so long ago.
   if (Args.hasFlag(options::OPT_fsycl_instrument_device_code,
-                   options::OPT_fno_sycl_instrument_device_code, false))
+                   options::OPT_fno_sycl_instrument_device_code, true))
     addLibraries(SYCLDeviceAnnotationLibs);
 
 #if !defined(_WIN32)

clang/test/Driver/sycl-instrumentation-old-model.c

@@ -20,12 +20,16 @@
 // CHECK-SPIRV-SAME: "{{.*}}libsycl-itt-stubs.bc"
 // CHECK-HOST-NOT: "-cc1"{{.*}} "-fsycl-is-host"{{.*}} "-fsycl-instrument-device-code"
 
-// ITT annotations in device code are disabled by default.
+// ITT annotations in device code are disabled by default. However, for SYCL offloading,
+// we still link ITT annotations libraries to ensure ABI compatibility with previous release.
 // RUN: %clangxx -fsycl --no-offload-new-driver -fsycl-targets=spir64 -### %s 2>&1 \
-// RUN: | FileCheck -check-prefixes=CHECK-NONPASSED %s
+// RUN: | FileCheck -check-prefixes=CHECK-ITT-LINK-ONLY %s
 // RUN: %clangxx -fsycl --no-offload-new-driver -fsycl-targets=nvptx64-nvidia-cuda -nocudalib -### %s 2>&1 \
 // RUN: | FileCheck -check-prefixes=CHECK-NONPASSED %s
 
+// CHECK-ITT-LINK-ONLY-NOT: "-fsycl-instrument-device-code"
+// CHECK-ITT-LINK-ONLY: llvm-link{{.*}} {{.*}}libsycl-itt-{{.*}}
+
 // RUN: %clangxx -fsycl --no-offload-new-driver -fno-sycl-instrument-device-code -fsycl-targets=spir64 -### %s 2>&1 \
 // RUN: | FileCheck -check-prefixes=CHECK-NONPASSED %s
 // RUN: %clangxx -fsycl --no-offload-new-driver -fsycl-targets=nvptx64-nvidia-cuda -fno-sycl-instrument-device-code -nocudalib -### %s 2>&1 \

clang/test/Driver/sycl-instrumentation.c

@@ -19,12 +19,16 @@
 // CHECK-SPIRV-SAME: libsycl-itt-compiler-wrappers.new.o
 // CHECK-SPIRV-SAME: libsycl-itt-stubs.new.o
 
-// ITT annotations in device code are disabled by default.
+// ITT annotations in device code are disabled by default. However, for SYCL offloading,
+// we still link ITT annotations libraries to ensure ABI compatibility with previous release.
 // RUN: %clangxx -fsycl --offload-new-driver -fsycl-targets=spir64 -### %s 2>&1 \
-// RUN: | FileCheck -check-prefixes=CHECK-NONPASSED %s
+// RUN: | FileCheck -check-prefixes=CHECK-ITT-LINK-ONLY %s
 // RUN: %clangxx -fsycl --offload-new-driver -fsycl-targets=nvptx64-nvidia-cuda -nocudalib -### %s 2>&1 \
 // RUN: | FileCheck -check-prefixes=CHECK-NONPASSED %s
 
+// CHECK-ITT-LINK-ONLY-NOT: "-fsycl-instrument-device-code"
+// CHECK-ITT-LINK-ONLY: clang-linker-wrapper{{.*}} {{.*}}libsycl-itt-{{.*}}
+
 // RUN: %clangxx -fsycl --offload-new-driver -fno-sycl-instrument-device-code -fsycl-targets=spir64 -### %s 2>&1 \
 // RUN: | FileCheck -check-prefixes=CHECK-NONPASSED %s
 // RUN: %clangxx -fsycl --offload-new-driver -fsycl-targets=nvptx64-nvidia-cuda -fno-sycl-instrument-device-code -nocudalib -### %s 2>&1 \

clang/test/Driver/sycl-offload-new-driver.c

@@ -34,7 +34,7 @@
 // RUN: %clangxx --target=x86_64-unknown-linux-gnu -fsycl --offload-new-driver \
 // RUN:          --sysroot=%S/Inputs/SYCL -### %s 2>&1 \
 // RUN:   | FileCheck -check-prefix WRAPPER_OPTIONS %s
-// WRAPPER_OPTIONS: clang-linker-wrapper{{.*}} "-sycl-device-libraries=libsycl-crt.new.o,libsycl-complex.new.o,libsycl-complex-fp64.new.o,libsycl-cmath.new.o,libsycl-cmath-fp64.new.o,libsycl-imf.new.o,libsycl-imf-fp64.new.o,libsycl-imf-bf16.new.o,libsycl-fallback-cassert.new.o,libsycl-fallback-cstring.new.o,libsycl-fallback-complex.new.o,libsycl-fallback-complex-fp64.new.o,libsycl-fallback-cmath.new.o,libsycl-fallback-cmath-fp64.new.o,libsycl-fallback-imf.new.o,libsycl-fallback-imf-fp64.new.o,libsycl-fallback-imf-bf16.new.o"
+// WRAPPER_OPTIONS: clang-linker-wrapper{{.*}} "-sycl-device-libraries=libsycl-crt.new.o,libsycl-complex.new.o,libsycl-complex-fp64.new.o,libsycl-cmath.new.o,libsycl-cmath-fp64.new.o,libsycl-imf.new.o,libsycl-imf-fp64.new.o,libsycl-imf-bf16.new.o,libsycl-fallback-cassert.new.o,libsycl-fallback-cstring.new.o,libsycl-fallback-complex.new.o,libsycl-fallback-complex-fp64.new.o,libsycl-fallback-cmath.new.o,libsycl-fallback-cmath-fp64.new.o,libsycl-fallback-imf.new.o,libsycl-fallback-imf-fp64.new.o,libsycl-fallback-imf-bf16.new.o,libsycl-itt-user-wrappers.new.o,libsycl-itt-compiler-wrappers.new.o,libsycl-itt-stubs.new.o"
 // WRAPPER_OPTIONS-SAME: "-sycl-device-library-location={{.*}}/lib"
 
 /// Verify phases used to generate SPIR-V instead of LLVM-IR