[AMDGPU] Remove detection of hip runtime for Spack (#133263)

There is special logic to detect the hip runtime when llvm is installed
with Spack. It works by matching the install prefix of llvm against
`llvm-amdgpu-*` followed by effectively globbing for

```
<llvm dir>/../hip-x.y.z-*/
```

and checking there is exactly one such directory.

I would suggest to remove autodetection for the following reasons:

1. In the Spack ecosystem it's by design that every package lives in
   its own prefix, and can only know where its dependencies are
   installed, it has no clue what its dependents are and where they are
installed. This heuristic detection breaks that invariant, since `hip`
   is a dependent of `llvm`, and can be surprising to Spack users.
2. The detection can lead to false positives, since users can be using
   an llvm installed "upstream" with their own build of hip locally, and
   they may not realize that clang is picking up upstream hip instead of
   their local copy.
3. It only works if the directory name is `llvm-amdgpu-*` which happens
   to be the name of AMD's fork of `llvm`, so it makes no sense that
   this code lives in the main LLVM repo for which the Spack package
   name is `llvm`. Feels wrong that LLVM knows about Spack package
   names, which can change over time.
4. Users can change the install directory structure, meaning that this
   detection is not robust under config changes in Spack.

Author: haampie

clang/lib/Driver/ToolChains/AMDGPU.cpp

@@ -32,48 +32,6 @@ using namespace clang::driver::toolchains;
 using namespace clang;
 using namespace llvm::opt;
 
-// Look for sub-directory starts with PackageName under ROCm candidate path.
-// If there is one and only one matching sub-directory found, append the
-// sub-directory to Path. If there is no matching sub-directory or there are
-// more than one matching sub-directories, diagnose them. Returns the full
-// path of the package if there is only one matching sub-directory, otherwise
-// returns an empty string.
-llvm::SmallString<0>
-RocmInstallationDetector::findSPACKPackage(const Candidate &Cand,
-                                           StringRef PackageName) {
-  if (!Cand.isSPACK())
-    return {};
-  std::error_code EC;
-  std::string Prefix = Twine(PackageName + "-" + Cand.SPACKReleaseStr).str();
-  llvm::SmallVector<llvm::SmallString<0>> SubDirs;
-  for (llvm::vfs::directory_iterator File = D.getVFS().dir_begin(Cand.Path, EC),
-                                     FileEnd;
-       File != FileEnd && !EC; File.increment(EC)) {
-    llvm::StringRef FileName = llvm::sys::path::filename(File->path());
-    if (FileName.starts_with(Prefix)) {
-      SubDirs.push_back(FileName);
-      if (SubDirs.size() > 1)
-        break;
-    }
-  }
-  if (SubDirs.size() == 1) {
-    auto PackagePath = Cand.Path;
-    llvm::sys::path::append(PackagePath, SubDirs[0]);
-    return PackagePath;
-  }
-  if (SubDirs.size() == 0 && Verbose) {
-    llvm::errs() << "SPACK package " << Prefix << " not found at " << Cand.Path
-                 << '\n';
-    return {};
-  }
-
-  if (SubDirs.size() > 1 && Verbose) {
-    llvm::errs() << "Cannot use SPACK package " << Prefix << " at " << Cand.Path
-                 << " due to multiple installations for the same version\n";
-  }
-  return {};
-}
-
 void RocmInstallationDetector::scanLibDevicePath(llvm::StringRef Path) {
   assert(!Path.empty());
 
@@ -187,10 +145,7 @@ RocmInstallationDetector::getInstallationPathCandidates() {
   auto DoPrintROCmSearchDirs = [&]() {
     if (PrintROCmSearchDirs)
       for (auto Cand : ROCmSearchDirs) {
-        llvm::errs() << "ROCm installation search path";
-        if (Cand.isSPACK())
-          llvm::errs() << " (Spack " << Cand.SPACKReleaseStr << ")";
-        llvm::errs() << ": " << Cand.Path << '\n';
+        llvm::errs() << "ROCm installation search path: " << Cand.Path << '\n';
       }
   };
 
@@ -226,22 +181,6 @@ RocmInstallationDetector::getInstallationPathCandidates() {
       ParentName = llvm::sys::path::filename(ParentDir);
     }
 
-    // Detect ROCm packages built with SPACK.
-    // clang is installed at
-    // <rocm_root>/llvm-amdgpu-<rocm_release_string>-<hash>/bin directory.
-    // We only consider the parent directory of llvm-amdgpu package as ROCm
-    // installation candidate for SPACK.
-    if (ParentName.starts_with("llvm-amdgpu-")) {
-      auto SPACKPostfix =
-          ParentName.drop_front(strlen("llvm-amdgpu-")).split('-');
-      auto SPACKReleaseStr = SPACKPostfix.first;
-      if (!SPACKReleaseStr.empty()) {
-        ParentDir = llvm::sys::path::parent_path(ParentDir);
-        return Candidate(ParentDir.str(), /*StrictChecking=*/true,
-                         SPACKReleaseStr);
-      }
-    }
-
     // Some versions of the rocm llvm package install to /opt/rocm/llvm/bin
     // Some versions of the aomp package install to /opt/rocm/aomp/bin
     if (ParentName == "llvm" || ParentName.starts_with("aomp"))
@@ -462,10 +401,6 @@ void RocmInstallationDetector::detectHIPRuntime() {
     InstallPath = Candidate.Path;
     if (InstallPath.empty() || !FS.exists(InstallPath))
       continue;
-    // HIP runtime built by SPACK is installed to
-    // <rocm_root>/hip-<rocm_release_string>-<hash> directory.
-    auto SPACKPath = findSPACKPackage(Candidate, "hip");
-    InstallPath = SPACKPath.empty() ? InstallPath : SPACKPath;
 
     BinPath = InstallPath;
     llvm::sys::path::append(BinPath, "bin");

clang/test/Driver/Inputs/rocm-spack/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5/bin/.hipVersion

@@ -94,33 +94,6 @@
 // RUN:   --print-rocm-search-dirs %s 2>&1 \
 // RUN:   | FileCheck -check-prefixes=ROCM-REL %s
 
-// Test ROCm installation built by SPACK by invoke clang at %t/rocm-spack/llvm-amdgpu-*
-// directory through a soft link.
-
-// RUN: rm -rf %t/rocm-spack
-// RUN: cp -r %S/Inputs/rocm-spack %t
-// RUN: ln -fs %clang %t/rocm-spack/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/bin/clang
-// RUN: %t/rocm-spack/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/bin/clang -### -no-canonical-prefixes -v \
-// RUN:   -resource-dir=%t/rocm-spack/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/lib/clang \
-// RUN:   -target x86_64-linux-gnu --cuda-gpu-arch=gfx900 --print-rocm-search-dirs %s 2>&1 \
-// RUN:   | FileCheck -check-prefixes=SPACK %s
-
-// Test SPACK installation with multiple hip and rocm-device-libs packages of the same
-// ROCm release. --hip-path and --rocm-device-lib-path can be used to specify them.
-
-// RUN: cp -r %t/rocm-spack/hip-* %t/rocm-spack/hip-4.0.0-abcd
-// RUN: %t/rocm-spack/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/bin/clang -### -no-canonical-prefixes -v \
-// RUN:   -target x86_64-linux-gnu --cuda-gpu-arch=gfx900 \
-// RUN:   --hip-path=%t/rocm-spack/hip-4.0.0-abcd \
-// RUN:    %s 2>&1 | FileCheck -check-prefixes=SPACK-SET %s
-
-// Test invalid SPACK ROCm installation missing hip and rocm-device-libs packages.
-
-// RUN: rm -rf %t/rocm-spack/hip-*
-// RUN: rm -rf %t/rocm-spack/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/amdgcn
-// RUN: %t/rocm-spack/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/bin/clang --version 2>&1 \
-// RUN:   | FileCheck -check-prefixes=SPACK-MISS-SILENT %s
-
 // GFX902-DEFAULTLIBS: error: cannot find ROCm device library for gfx902; provide its path via '--rocm-path' or '--rocm-device-lib-path', or pass '-nogpulib' to build without ROCm device library
 
 // NODEFAULTLIBS-NOT: error: cannot find
@@ -145,23 +118,3 @@
 
 // ROCM-REL: ROCm installation search path: {{.*}}/opt/rocm
 // ROCM-REL: ROCm installation search path: {{.*}}/opt/rocm-3.10.0
-
-// SPACK: InstalledDir: [[DIR:.*]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/bin
-// SPACK: ROCm installation search path (Spack 4.0.0): [[DIR]]
-// SPACK: ROCm installation search path: [[CLANG:.*]]
-// SPACK: ROCm installation search path: [[DIR]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z
-// SPACK: ROCm installation search path: [[DIR]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/lib/clang
-// SPACK: ROCm installation search path: /opt/rocm
-// SPACK: Found HIP installation: [[DIR]]/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5, version 4.0.20214-a2917cd
-// SPACK: "-triple" "amdgcn-amd-amdhsa"
-// SPACK-SAME: "-mlink-builtin-bitcode" "[[DIR]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/amdgcn/bitcode/hip.bc"
-// SPACK-SAME: "-idirafter" "[[DIR]]/hip-4.0.0-5f63slrursbrvfe2txrrjkynbsywsob5/include"
-
-// SPACK-SET: InstalledDir: [[DIR:.*]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/bin
-// SPACK-SET: Found HIP installation: [[DIR]]/hip-4.0.0-abcd, version 4.0.20214-a2917cd
-// SPACK-SET: "-triple" "amdgcn-amd-amdhsa"
-// SPACK-SET-SAME: "-mlink-builtin-bitcode" "[[DIR]]/llvm-amdgpu-4.0.0-ieagcs7inf7runpyfvepqkurasoglq4z/amdgcn/bitcode/hip.bc"
-// SPACK-SET-SAME: "-idirafter" "[[DIR]]/hip-4.0.0-abcd/include"
-
-// SPACK-MISS-SILENT-NOT: SPACK package hip-{{.*}} not found at
-// SPACK-MISS-SILENT-NOT: Found HIP installation