Re-land [CodeView] Add full repro to LF_BUILDINFO record

This patch writes the full -cc1 command into the resulting .OBJ, like MSVC does. This allows for external tools (Recode, Live++) to rebuild a source file without any external dependency but the .OBJ itself (other than the compiler) and without knowledge of the build system.

The LF_BUILDINFO record stores a full path to the compiler, the PWD (CWD at program startup), a relative or absolute path to the source, and the full CC1 command line. The stored command line is self-standing (does not depend on the environment). In the same way, MSVC doesn't exactly store the provided command-line, but an expanded version (a somehow equivalent of CC1) which is also self-standing.

For more information see PR36198 and D43002.

Differential Revision: https://reviews.llvm.org/D80833

1 files changed, 39 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index bb795a8..9a8188e 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -68,6 +68,7 @@
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/Path.h"
+#include "llvm/Support/Program.h"
 #include "llvm/Support/SMLoc.h"
 #include "llvm/Support/ScopedPrinter.h"
 #include "llvm/Target/TargetLoweringObjectFile.h"
@@ -889,6 +890,34 @@ static TypeIndex getStringIdTypeIdx(GlobalTypeTableBuilder &TypeTable,
   return TypeTable.writeLeafType(SIR);
 }
 
+static std::string flattenCommandLine(ArrayRef<std::string> Args,
+                                      StringRef MainFilename) {
+  std::string FlatCmdLine;
+  raw_string_ostream OS(FlatCmdLine);
+  bool PrintedOneArg = false;
+  if (!StringRef(Args[0]).contains("-cc1")) {
+    llvm::sys::printArg(OS, "-cc1", /*Quote=*/true);
+    PrintedOneArg = true;
+  }
+  for (unsigned i = 0; i < Args.size(); i++) {
+    StringRef Arg = Args[i];
+    if (Arg.empty())
+      continue;
+    if (Arg == "-main-file-name" || Arg == "-o") {
+      i++; // Skip this argument and next one.
+      continue;
+    }
+    if (Arg.startswith("-object-file-name") || Arg == MainFilename)
+      continue;
+    if (PrintedOneArg)
+      OS << " ";
+    llvm::sys::printArg(OS, Arg, /*Quote=*/true);
+    PrintedOneArg = true;
+  }
+  OS.flush();
+  return FlatCmdLine;
+}
+
 void CodeViewDebug::emitBuildInfo() {
   // First, make LF_BUILDINFO. It's a sequence of strings with various bits of
   // build info. The known prefix is:
@@ -909,8 +938,16 @@ void CodeViewDebug::emitBuildInfo() {
       getStringIdTypeIdx(TypeTable, MainSourceFile->getDirectory());
   BuildInfoArgs[BuildInfoRecord::SourceFile] =
       getStringIdTypeIdx(TypeTable, MainSourceFile->getFilename());
-  // FIXME: Path to compiler and command line. PDB is intentionally blank unless
-  // we implement /Zi type servers.
+  // FIXME: PDB is intentionally blank unless we implement /Zi type servers.
+  BuildInfoArgs[BuildInfoRecord::TypeServerPDB] =
+      getStringIdTypeIdx(TypeTable, "");
+  if (Asm->TM.Options.MCOptions.Argv0 != nullptr) {
+    BuildInfoArgs[BuildInfoRecord::BuildTool] =
+        getStringIdTypeIdx(TypeTable, Asm->TM.Options.MCOptions.Argv0);
+    BuildInfoArgs[BuildInfoRecord::CommandLine] = getStringIdTypeIdx(
+        TypeTable, flattenCommandLine(Asm->TM.Options.MCOptions.CommandLineArgs,
+                                      MainSourceFile->getFilename()));
+  }
   BuildInfoRecord BIR(BuildInfoArgs);
   TypeIndex BuildInfoIndex = TypeTable.writeLeafType(BIR);