[HIP][SPIRV] Create an intermediate file for the llvm-link output (#162096)

Before this patch we had:
>    clang -cc1 source.c -o bitcode.bc
>    llvm-link -o a.out bitcode.bc
>    llvm-spirv -o a.out a.out

Now we have:
>    clang -cc1 source.c -o bitcode.bc
>    llvm-link -o a-linked.bc bitcode.bc
>    llvm-spirv -o a.out a-linked.bc

Co-authored-by: Manuel Carrasco <macarras@amd.com>

Author: jmmartinez

clang/lib/Driver/ToolChains/HIPAMD.cpp

@@ -168,9 +168,12 @@ void AMDGCN::Linker::constructLinkAndEmitSpirvCommand(
     const InputInfo &Output, const llvm::opt::ArgList &Args) const {
   assert(!Inputs.empty() && "Must have at least one input.");
 
-  constructLlvmLinkCommand(C, JA, Inputs, Output, Args);
+  std::string LinkedBCFilePrefix(
+      Twine(llvm::sys::path::stem(Output.getFilename()), "-linked").str());
+  const char *LinkedBCFilePath = HIP::getTempFile(C, LinkedBCFilePrefix, "bc");
+  InputInfo LinkedBCFile(&JA, LinkedBCFilePath, Output.getBaseInput());
 
-  // Linked BC is now in Output
+  constructLlvmLinkCommand(C, JA, Inputs, LinkedBCFile, Args);
 
   // Emit SPIR-V binary.
   llvm::opt::ArgStringList TrArgs{
@@ -180,7 +183,7 @@ void AMDGCN::Linker::constructLinkAndEmitSpirvCommand(
       "--spirv-lower-const-expr",
       "--spirv-preserve-auxdata",
       "--spirv-debug-info-version=nonsemantic-shader-200"};
-  SPIRV::constructTranslateCommand(C, *this, JA, Output, Output, TrArgs);
+  SPIRV::constructTranslateCommand(C, *this, JA, Output, LinkedBCFile, TrArgs);
 }
 
 // For amdgcn the inputs of the linker job are device bitcode and output is

clang/lib/Driver/ToolChains/HIPSPV.cpp

@@ -22,17 +22,6 @@ using namespace clang::driver::tools;
 using namespace clang;
 using namespace llvm::opt;
 
-// Convenience function for creating temporary file for both modes of
-// isSaveTempsEnabled().
-static const char *getTempFile(Compilation &C, StringRef Prefix,
-                               StringRef Extension) {
-  if (C.getDriver().isSaveTempsEnabled()) {
-    return C.getArgs().MakeArgString(Prefix + "." + Extension);
-  }
-  auto TmpFile = C.getDriver().GetTemporaryPath(Prefix, Extension);
-  return C.addTempFile(C.getArgs().MakeArgString(TmpFile));
-}
-
 // Locates HIP pass plugin.
 static std::string findPassPlugin(const Driver &D,
                                   const llvm::opt::ArgList &Args) {
@@ -65,7 +54,7 @@ void HIPSPV::Linker::constructLinkAndEmitSpirvCommand(
 
   assert(!Inputs.empty() && "Must have at least one input.");
   std::string Name = std::string(llvm::sys::path::stem(Output.getFilename()));
-  const char *TempFile = getTempFile(C, Name + "-link", "bc");
+  const char *TempFile = HIP::getTempFile(C, Name + "-link", "bc");
 
   // Link LLVM bitcode.
   ArgStringList LinkArgs{};
@@ -93,7 +82,7 @@ void HIPSPV::Linker::constructLinkAndEmitSpirvCommand(
   auto PassPluginPath = findPassPlugin(C.getDriver(), Args);
   if (!PassPluginPath.empty()) {
     const char *PassPathCStr = C.getArgs().MakeArgString(PassPluginPath);
-    const char *OptOutput = getTempFile(C, Name + "-lower", "bc");
+    const char *OptOutput = HIP::getTempFile(C, Name + "-lower", "bc");
     ArgStringList OptArgs{TempFile,     "-load-pass-plugin",
                           PassPathCStr, "-passes=hip-post-link-passes",
                           "-o",         OptOutput};

clang/lib/Driver/ToolChains/HIPUtility.cpp

@@ -472,3 +472,14 @@ void HIP::constructGenerateObjFileFromHIPFatBinary(
                                          D.getClangProgramPath(), ClangArgs,
                                          Inputs, Output, D.getPrependArg()));
 }
+
+// Convenience function for creating temporary file for both modes of
+// isSaveTempsEnabled().
+const char *HIP::getTempFile(Compilation &C, StringRef Prefix,
+                             StringRef Extension) {
+  if (C.getDriver().isSaveTempsEnabled()) {
+    return C.getArgs().MakeArgString(Prefix + "." + Extension);
+  }
+  auto TmpFile = C.getDriver().GetTemporaryPath(Prefix, Extension);
+  return C.addTempFile(C.getArgs().MakeArgString(TmpFile));
+}

clang/lib/Driver/ToolChains/HIPUtility.h

@@ -16,6 +16,8 @@ namespace driver {
 namespace tools {
 namespace HIP {
 
+const char *getTempFile(Compilation &C, StringRef Prefix, StringRef Extension);
+
 // Construct command for creating HIP fatbin.
 void constructHIPFatbinCommand(Compilation &C, const JobAction &JA,
                                StringRef OutputFileName,

clang/test/Driver/hip-toolchain-no-rdc.hip

@@ -207,7 +207,7 @@
 //
 
 // AMDGCNSPIRV: "-cc1" "-triple" "spirv64-amd-amdhsa" {{.*}}"-emit-llvm-bc" {{.*}}"-fembed-bitcode=marker" "-disable-llvm-passes" {{.*}} "-o" "[[AMDGCNSPV_BC:.*bc]]"
-// AMDGCNSPIRV: {{".*llvm-link.*"}} "-o" "[[AMDGCNSPV_TMP:.*out]]" "[[AMDGCNSPV_BC]]"
+// AMDGCNSPIRV: {{".*llvm-link.*"}} "-o" "[[AMDGCNSPV_TMP:.*bc]]" "[[AMDGCNSPV_BC]]"
 // AMDGCNSPIRV: {{".*llvm-spirv.*"}} "--spirv-max-version=1.6" "--spirv-ext=+all" {{.*}} "[[AMDGCNSPV_TMP]]" {{.*}}"-o" "[[AMDGCNSPV_CO:.*out]]"
 // AMDGCNSPIRV: "-cc1" "-triple" "amdgcn-amd-amdhsa" {{.*}}"-emit-obj" {{.*}}"-target-cpu" "gfx900"{{.*}} "-o" "[[GFX900_OBJ:.*o]]"
 // AMDGCNSPIRV: {{".*lld.*"}} {{.*}}"-plugin-opt=mcpu=gfx900" {{.*}} "-o" "[[GFX900_CO:.*out]]" {{.*}}"[[GFX900_OBJ]]"

clang/test/Driver/spirv-amd-toolchain.c

@@ -15,5 +15,5 @@
 // RUN: %clang -### --target=spirv64-amd-amdhsa %s -nogpulib -nogpuinc 2>&1 \
 // RUN:   | FileCheck %s --check-prefix=INVOCATION
 // INVOCATION: "-cc1" "-triple" "spirv64-amd-amdhsa" {{.*}}"-disable-llvm-optzns" {{.*}} "-o" "[[OUTPUT:.+]]" "-x" "c"
-// INVOCATION: "{{.*}}llvm-link" "-o" "a.out" "[[OUTPUT]]"
-// INVOCATION: "{{.*}}llvm-spirv" "--spirv-max-version=1.6" "--spirv-ext=+all" "--spirv-allow-unknown-intrinsics" "--spirv-lower-const-expr" "--spirv-preserve-auxdata" "--spirv-debug-info-version=nonsemantic-shader-200" "a.out" "-o" "a.out"
+// INVOCATION: "{{.*}}llvm-link" "-o" "[[LINKED_OUTPUT:.+]]" "[[OUTPUT]]"
+// INVOCATION: "{{.*}}llvm-spirv" "--spirv-max-version=1.6" "--spirv-ext=+all" "--spirv-allow-unknown-intrinsics" "--spirv-lower-const-expr" "--spirv-preserve-auxdata" "--spirv-debug-info-version=nonsemantic-shader-200" "[[LINKED_OUTPUT]]" "-o" "a.out"