[New offload][llc] Pass -relocation-model=pic option to llc when building shared libraries (#13687)

When user is building a shared library using '-shared' option, the llc
step run after wrapping device code needs to be run with
'-relocation-model=pic' option. This PR adds the above option for the
new offloading model.
One other change has been added to address test failures resulting from
adding a new SYCL E2E test:
- Wrapper logic needs to use the 'arch' to specify the target and not
use the entire triple. This is required for successful parsing by SYCL
runtime.

Thanks

---------

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

Author: asudarsa

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

@@ -10,3 +10,7 @@
 // CHK-CMDS-NEXT: offload-wrapper: input: [[LLVMSPIRVOUT:.*]].table, output: [[WRAPPEROUT:.*]].bc
 // CHK-CMDS-NEXT: "{{.*}}llc" -filetype=obj -o [[LLCOUT:.*]].o [[WRAPPEROUT]].bc
 // CHK-CMDS-NEXT: "{{.*}}/ld" -- HOST_LINKER_FLAGS -dynamic-linker HOST_DYN_LIB -o a.out [[LLCOUT]].o HOST_LIB_PATH HOST_STAT_LIB {{.*}}test-sycl.o
+
+/// check for PIC for device wrap compilation when using -shared
+// RUN: clang-linker-wrapper -sycl-device-library-location=%S/Inputs -sycl-device-libraries=libsycl-crt.new.o,libsycl-complex.new.o -sycl-post-link-options="SYCL_POST_LINK_OPTIONS" -llvm-spirv-options="LLVM_SPIRV_OPTIONS" "--host-triple=x86_64-unknown-linux-gnu" "--triple=spir64" "--linker-path=/usr/bin/ld" -shared "--" HOST_LINKER_FLAGS "-dynamic-linker" HOST_DYN_LIB "-o" "a.out" HOST_LIB_PATH HOST_STAT_LIB %S/Inputs/test-sycl.o --dry-run 2>&1 | FileCheck -check-prefix=CHK-SHARED %s
+// CHK-SHARED: "{{.*}}llc"{{.*}} -relocation-model=pic

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

@@ -31,7 +31,7 @@ int main() {
 // CHECK-DAG: %__sycl.tgt_device_image = type { i16, i8, i8, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr }
 // CHECK-DAG: %__sycl.tgt_bin_desc = type { i16, i16, ptr, ptr, ptr }
 
-// CHECK-DAG: @.sycl_offloading.target.0 = internal unnamed_addr constant [23 x i8] c"spir64-unknown-unknown\00"
+// CHECK-DAG: @.sycl_offloading.target.0 = internal unnamed_addr constant [7 x i8] c"spir64\00"
 // CHECK-DAG: @.sycl_offloading.opts.compile.0 = internal unnamed_addr constant [1 x i8] zeroinitializer
 // CHECK-DAG: @.sycl_offloading.opts.link.0 = internal unnamed_addr constant [1 x i8] zeroinitializer
 // CHECK-DAG: @prop = internal unnamed_addr constant [17 x i8] c"DeviceLibReqMask\00"

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

@@ -77,3 +77,9 @@
 // DEVICE_ONLY: 2: compiler, {1}, ir, (device-sycl)
 // DEVICE_ONLY: 3: backend, {2}, ir, (device-sycl)
 // DEVICE_ONLY: 4: offload, "device-sycl (spir64-unknown-unknown)" {3}, none
+
+/// check for -shared transmission to clang-linker-wrapper tool
+// RUN: %clangxx -### -fsycl --offload-new-driver -target x86_64-unknown-linux-gnu \
+// RUN:          -shared %s 2>&1 \
+// RUN:  | FileCheck -check-prefix=CHECK_SHARED %s
+// CHECK_SHARED: clang-linker-wrapper{{.*}} "-shared"

clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp

@@ -767,8 +767,13 @@ Expected<StringRef> wrapSYCLBinariesFromFile(StringRef InputFile,
         inconvertibleErrorCode(),
         "can't wrap SYCL image. -triple argument is missed.");
 
+  // SYCL runtime currently works for spir64 target triple and not for
+  // spir64-unknown-unknown.
+  // TODO: Fix SYCL runtime to accept both triple
+  llvm::Triple T(Target);
+  StringRef A(T.getArchName());
   for (offloading::SYCLImage &Image : Images)
-    Image.Target = Target;
+    Image.Target = A;
 
   LLVMContext C;
   Module M("offload.wrapper.object", C);
@@ -814,6 +819,9 @@ static Expected<StringRef> runCompile(StringRef &InputFile,
 
   SmallVector<StringRef, 8> CmdArgs;
   CmdArgs.push_back(*LLCPath);
+  // Checking for '-shared' linker option
+  if (Args.hasArg(OPT_shared))
+    CmdArgs.push_back("-relocation-model=pic");
   CmdArgs.push_back("-filetype=obj");
   CmdArgs.push_back("-o");
   CmdArgs.push_back(*OutputFileOrErr);

clang/tools/clang-linker-wrapper/LinkerWrapperOpts.td

@@ -135,6 +135,9 @@ def relocatable : Flag<["--", "-"], "relocatable">,
     HelpText<"Link device code to create a relocatable offloading application">;
 def r : Flag<["-"], "r">, Alias<relocatable>;
 
+def shared : Flag<["--", "-"], "shared">,
+    HelpText<"Link device code to create a shared library">;
+
 // link.exe-style linker options.
 def out : Joined<["/", "-", "/?", "-?"], "out:">, Flags<[HelpHidden]>;
 def libpath : Joined<["/", "-", "/?", "-?"], "libpath:">, Flags<[HelpHidden]>;

sycl/CMakeLists.txt

@@ -414,6 +414,8 @@ set( SYCL_TOOLCHAIN_DEPLOY_COMPONENTS
      clang-offload-bundler
      clang-offload-deps
      clang-offload-extract
+     clang-offload-packager
+     clang-linker-wrapper
      file-table-tform
      llc
      llvm-ar

sycl/test-e2e/SharedLib/use_when_link_new_offload.cpp

@@ -0,0 +1,14 @@
+// REQUIRES: opencl, cpu, linux
+// This test checks for correct behavior for shared library builds when new
+// offload driver is enabled. Currently, new offload model supports only JIT.
+// TODO: Expand the test once AOT support for new offload model is ready.
+//
+// RUN: %clangxx -fsycl -fsycl-targets=spir64 --offload-new-driver -DBUILD_LIB -fPIC -shared %s -o %T/lib%basename_t.so
+
+// RUN: %clangxx -fsycl -fsycl-targets=spir64 --offload-new-driver -DFOO_FIRST -L%T %s -o %t.out -l%basename_t -Wl,-rpath=%T
+// RUN: %{run} %t.out
+
+// RUN: %clangxx -fsycl -fsycl-targets=spir64 --offload-new-driver -L%T %s -o %t.out -l%basename_t -Wl,-rpath=%T
+// RUN: %{run} %t.out
+
+#include "use_when_link.cpp"