Address review comments

Signed-off-by: Arvind Sudarsanam <[email protected]>

Author: asudarsa

clang/docs/ClangSYCLLinker.rst

@@ -56,6 +56,7 @@ be passed down to downstream tools like 'llvm-link', 'llvm-spirv', etc.
     -help-hidden                  Display all available options
     -help                         Display available options (--help-hidden for more)
     --library-path=<dir>          Set the library path for SYCL device libraries
+    --device-libs=<value>         A comma separated list of device libraries that are linked during the device link
     -o <path>                     Path to file to write output
     --save-temps                  Save intermediate results
     --triple <value>              Specify the target triple.
@@ -64,6 +65,7 @@ be passed down to downstream tools like 'llvm-link', 'llvm-spirv', etc.
     -spirv-dump-device-code=<dir> Directory to dump SPIR-V IR code into
     -is-windows-msvc-env          Specify if we are compiling under windows environment
     -llvm-spirv-options=<value>   Pass options to llvm-spirv tool
+    --llvm-spirv-path=<dir>       Set the system llvm-spirv path
 
 Example
 =======

clang/test/Driver/clang-sycl-linker-test.cpp

@@ -2,8 +2,10 @@
 //
 // Test a simple case without arguments
 // RUN: %clangxx -fsycl -emit-llvm -c %s -o %t.bc
-// RUN: clang-sycl-linker --dry-run -triple spirv64 %t.bc --library-path=%S/Inputs -o a.spv 2>&1 \
+// RUN: echo ' ' > %T/lib1.bc
+// RUN: echo ' ' > %T/lib2.bc
+// RUN: clang-sycl-linker --dry-run -triple spirv64 %t.bc --library-path=%T --device-libs=lib1.bc,lib2.bc -o a.spv 2>&1 \
 // RUN:   | FileCheck %s --check-prefix=CMDS
 // CMDS: "{{.*}}llvm-link{{.*}}" {{.*}}.bc -o [[FIRSTLLVMLINKOUT:.*]].bc --suppress-warnings
-// CMDS-NEXT: "{{.*}}llvm-link{{.*}}" -only-needed [[FIRSTLLVMLINKOUT]].bc {{.*}}libsycl-crt.bc {{.*}}libsycl-complex.bc -o [[SECONDLLVMLINKOUT:.*]].bc --suppress-warnings
+// CMDS-NEXT: "{{.*}}llvm-link{{.*}}" -only-needed [[FIRSTLLVMLINKOUT]].bc {{.*}}lib1.bc {{.*}}lib2.bc -o [[SECONDLLVMLINKOUT:.*]].bc --suppress-warnings
 // CMDS-NEXT: "{{.*}}llvm-spirv{{.*}}" {{.*}}-o a.spv [[SECONDLLVMLINKOUT]].bc

clang/tools/clang-sycl-linker/ClangSYCLLinker.cpp

@@ -156,19 +156,6 @@ Expected<std::string> findProgram(const ArgList &Args, StringRef Name,
   return *Path;
 }
 
-std::optional<std::string> findFile(StringRef Dir, StringRef Root,
-                                    const Twine &Name) {
-  SmallString<128> Path;
-  if (Dir.starts_with("="))
-    sys::path::append(Path, Root, Dir.substr(1), Name);
-  else
-    sys::path::append(Path, Dir, Name);
-
-  if (sys::fs::exists(Path))
-    return static_cast<std::string>(Path);
-  return std::nullopt;
-}
-
 void printCommands(ArrayRef<StringRef> CmdArgs) {
   if (CmdArgs.empty())
     return;
@@ -238,43 +225,31 @@ Expected<StringRef> linkDeviceInputFiles(ArrayRef<std::string> InputFiles,
   return *OutFileOrErr;
 }
 
-const SmallVector<std::string> SYCLDeviceLibNames = {
-    "libsycl-crt.bc",
-    "libsycl-complex.bc",
-    "libsycl-complex-fp64.bc",
-    "libsycl-cmath.bc",
-    "libsycl-cmath-fp64.bc",
-    "libsycl-imf.bc",
-    "libsycl-imf-fp64.bc",
-    "libsycl-imf-bf16.bc",
-    "libsycl-fallback-cassert.bc",
-    "libsycl-fallback-cstring.bc",
-    "libsycl-fallback-complex.bc",
-    "libsycl-fallback-complex-fp64.bc",
-    "libsycl-fallback-cmath.bc",
-    "libsycl-fallback-cmath-fp64.bc",
-    "libsycl-fallback-imf.bc",
-    "libsycl-fallback-imf-fp64.bc",
-    "libsycl-fallback-imf-bf16.bc",
-    "libsycl-fallback-bfloat16.bc",
-    "libsycl-native-bfloat16.bc",
-    "libsycl-itt-user-wrappers.bc",
-    "libsycl-itt-compiler-wrappers.bc",
-    "libsycl-itt-stubs.bc",
-    "libsycl-sanitizer.bc"};
-
-Expected<SmallVector<std::string>> getSYCLDeviceLibFiles(const ArgList &Args) {
+// This utility function is used to gather all SYCL device library files that
+// will be linked with input device files.
+// The list of files and its location are passed from driver.
+Expected<SmallVector<std::string>> getSYCLDeviceLibs(const ArgList &Args) {
   SmallVector<std::string> DeviceLibFiles;
   StringRef LibraryPath;
   if (Arg *A = Args.getLastArg(OPT_library_path_EQ))
     LibraryPath = A->getValue();
   if (LibraryPath.empty())
     return DeviceLibFiles;
-  for (auto &DeviceLibName : SYCLDeviceLibNames) {
-    std::optional<std::string> Filename =
-        findFile(LibraryPath, /*Root=*/"", DeviceLibName);
-    if (Filename)
-      DeviceLibFiles.push_back(*Filename);
+  if (Arg *A = Args.getLastArg(OPT_device_libs_EQ)) {
+    if (A->getValues().size() == 0)
+      return createStringError(
+          inconvertibleErrorCode(),
+          "Number of device library files cannot be zero.");
+    for (StringRef Val : A->getValues()) {
+      SmallString<128> LibName(LibraryPath);
+      llvm::sys::path::append(LibName, Val);
+      if (llvm::sys::fs::exists(LibName))
+        DeviceLibFiles.push_back(std::string(LibName));
+      else
+        return createStringError(inconvertibleErrorCode(),
+                                 std::string(LibName) +
+                                     " SYCL device library file is not found.");
+    }
   }
   return DeviceLibFiles;
 }
@@ -288,7 +263,7 @@ static Expected<StringRef> linkDeviceLibFiles(StringRef InputFile,
                                               const ArgList &Args) {
   llvm::TimeTraceScope TimeScope("LinkDeviceLibraryFiles");
 
-  auto SYCLDeviceLibFiles = getSYCLDeviceLibFiles(Args);
+  auto SYCLDeviceLibFiles = getSYCLDeviceLibs(Args);
   if (!SYCLDeviceLibFiles)
     return SYCLDeviceLibFiles.takeError();
   if ((*SYCLDeviceLibFiles).empty())
@@ -472,8 +447,7 @@ int main(int argc, char **argv) {
 
   if (Args.hasArg(OPT_help) || Args.hasArg(OPT_help_hidden)) {
     Tbl.printHelp(
-        outs(),
-        "clang-sycl-linker [options] <options to sycl link steps>",
+        outs(), "clang-sycl-linker [options] <options to sycl link steps>",
         "A utility that wraps around several steps required to link SYCL "
         "device files.\n"
         "This enables LLVM IR linking, post-linking and code generation for "

clang/tools/clang-sycl-linker/SYCLLinkOpts.td

@@ -20,6 +20,10 @@ def output : Separate<["--"], "output-file">, Alias<o>, Flags<[HelpHidden]>,
 def library_path_EQ : Joined<["--", "-"], "library-path=">,
   Flags<[HelpHidden]>, HelpText<"Add <dir> to the library search path">;
 
+def device_libs_EQ : CommaJoined<["--", "-"], "device-libs=">,
+  Flags<[WrapperOnlyOption]>,
+  HelpText<"A comma separated list of device libraries that are linked during the device link.">;
+
 def triple : Joined<["--"], "triple">,
   HelpText<"The device target triple">;
 def arch : Separate<["--", "-"], "arch">,
@@ -41,6 +45,10 @@ def spirv_dump_device_code_EQ : Joined<["--", "-"], "spirv-dump-device-code=">,
 def is_windows_msvc_env : Flag<["--", "-"], "is-windows-msvc-env">,
   Flags<[WrapperOnlyOption, HelpHidden]>;
 
+def llvm_spirv_path_EQ : Joined<["--"], "llvm-spirv-path=">,
+  Flags<[WrapperOnlyOption]>, MetaVarName<"<dir>">,
+  HelpText<"Set the system llvm-spirv path">;
+
 // Options to pass to llvm-spirv tool
 def llvm_spirv_options_EQ : Joined<["--", "-"], "llvm-spirv-options=">,
   Flags<[WrapperOnlyOption]>,