[AIX] Add git revision to .file string (#88164)

If `LLVM_APPEND_VC_REV` is on, add the git revision to the `.file`
string. The revision can be set with `LLVM_FORCE_VC_REVISION`.

Before:
`.file	"git_revision.cpp",,"LLVM version 19.0.0git"`

After:
`.file	"git_revision.cpp",,"LLVM version 19.0.0git (LLVM_REVISION)"`

Author: jakeegan

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -114,6 +114,7 @@
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Timer.h"
+#include "llvm/Support/VCSRevision.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetLoweringObjectFile.h"
 #include "llvm/Target/TargetMachine.h"
@@ -497,12 +498,15 @@ bool AsmPrinter::doInitialization(Module &M) {
     else
       FileName = M.getSourceFileName();
     if (MAI->hasFourStringsDotFile()) {
-#ifdef PACKAGE_VENDOR
       const char VerStr[] =
-          PACKAGE_VENDOR " " PACKAGE_NAME " version " PACKAGE_VERSION;
-#else
-      const char VerStr[] = PACKAGE_NAME " version " PACKAGE_VERSION;
+#ifdef PACKAGE_VENDOR
+          PACKAGE_VENDOR " "
+#endif
+          PACKAGE_NAME " version " PACKAGE_VERSION
+#ifdef LLVM_REVISION
+                         " (" LLVM_REVISION ")"
 #endif
+          ;
       // TODO: Add timestamp and description.
       OutStreamer->emitFileDirective(FileName, VerStr, "", "");
     } else {

llvm/test/CMakeLists.txt

@@ -25,6 +25,7 @@ llvm_canonicalize_cmake_booleans(
   LLVM_INCLUDE_DXIL_TESTS
   LLVM_TOOL_LLVM_DRIVER_BUILD
   LLVM_INCLUDE_SPIRV_TOOLS_TESTS
+  LLVM_APPEND_VC_REV
   )
 
 configure_lit_site_cfg(

llvm/test/CodeGen/PowerPC/git_revision.ll

@@ -0,0 +1,12 @@
+; Check that the git revision is contained in the assembly/object files
+
+; REQUIRES: vc-rev-enabled 
+
+; RUN: llc < %s | FileCheck %s -DREVISION=git-revision
+; RUN: llc -filetype=obj < %s | FileCheck %s -DREVISION=git-revision
+
+; CHECK: ([[REVISION]])
+
+source_filename = "git_revision.cpp"
+target datalayout = "E-m:a-Fi64-i64:64-n32:64-S128-v256:256:256-v512:512:512"
+target triple = "powerpc64-ibm-aix7.2.0.0"

llvm/test/CodeGen/PowerPC/lit.local.cfg

@@ -1,4 +1,23 @@
 if not "PowerPC" in config.root.targets:
     config.unsupported = True
 
+import subprocess
+
 config.suffixes.add(".py")
+
+def get_revision(repo_path):
+    cmd = ['git', '-C', repo_path, 'rev-parse', 'HEAD']
+    try:
+        return subprocess.run(cmd, stdout=subprocess.PIPE, check=True).stdout.decode()
+    except subprocess.CalledProcessError:
+        print("An error occurred retrieving the git revision.")
+        return None
+
+if config.have_vc_rev:
+    if config.force_vc_rev:
+        git_revision = config.force_vc_rev
+    else:
+        git_revision = get_revision(config.llvm_src_root)
+    if git_revision:
+        config.substitutions.append(("git-revision", git_revision))
+        config.available_features.add("vc-rev-enabled")

llvm/test/lit.site.cfg.py.in

@@ -61,6 +61,8 @@ config.reverse_iteration = @LLVM_ENABLE_REVERSE_ITERATION@
 config.dxil_tests = @LLVM_INCLUDE_DXIL_TESTS@
 config.have_llvm_driver = @LLVM_TOOL_LLVM_DRIVER_BUILD@
 config.spirv_tools_tests = @LLVM_INCLUDE_SPIRV_TOOLS_TESTS@
+config.have_vc_rev = @LLVM_APPEND_VC_REV@
+config.force_vc_rev = "@LLVM_FORCE_VC_REVISION@"
 
 import lit.llvm
 lit.llvm.initialize(lit_config, config)