add -C embed-source=yes to embed source code in dwarf debug info

Author: Mrmaxmeier

compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs

@@ -639,6 +639,8 @@ pub fn file_metadata<'ll>(cx: &CodegenCx<'ll, '_>, source_file: &SourceFile) ->
         };
         let hash_value = hex_encode(source_file.src_hash.hash_bytes());
 
+        let source = cx.sess().opts.cg.embed_source.then_some(()).and(source_file.src.as_ref());
+
         unsafe {
             llvm::LLVMRustDIBuilderCreateFile(
                 DIB(cx),
@@ -649,6 +651,8 @@ pub fn file_metadata<'ll>(cx: &CodegenCx<'ll, '_>, source_file: &SourceFile) ->
                 hash_kind,
                 hash_value.as_ptr().cast(),
                 hash_value.len(),
+                source.map(|x| x.as_ptr().cast()).unwrap_or(ptr::null()),
+                source.map(|x| x.len()).unwrap_or(0),
             )
         }
     }
@@ -669,6 +673,8 @@ pub fn unknown_file_metadata<'ll>(cx: &CodegenCx<'ll, '_>) -> &'ll DIFile {
             llvm::ChecksumKind::None,
             hash_value.as_ptr().cast(),
             hash_value.len(),
+            ptr::null(),
+            0,
         )
     })
 }
@@ -915,6 +921,8 @@ pub fn build_compile_unit_di_node<'ll, 'tcx>(
             llvm::ChecksumKind::None,
             ptr::null(),
             0,
+            ptr::null(),
+            0,
         );
 
         let unit_metadata = llvm::LLVMRustDIBuilderCreateCompileUnit(

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -1856,6 +1856,8 @@ extern "C" {
         CSKind: ChecksumKind,
         Checksum: *const c_char,
         ChecksumLen: size_t,
+        Source: *const c_char,
+        SourceLen: size_t,
     ) -> &'a DIFile;
 
     pub fn LLVMRustDIBuilderCreateSubroutineType<'a>(

compiler/rustc_interface/src/tests.rs

@@ -605,6 +605,7 @@ fn test_codegen_options_tracking_hash() {
     tracked!(debug_assertions, Some(true));
     tracked!(debuginfo, DebugInfo::Limited);
     tracked!(embed_bitcode, false);
+    tracked!(embed_source, true);
     tracked!(force_frame_pointers, FramePointer::Always);
     tracked!(force_unwind_tables, Some(true));
     tracked!(inline_threshold, Some(0xf007ba11));

compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp

@@ -888,15 +888,19 @@ extern "C" LLVMMetadataRef LLVMRustDIBuilderCreateFile(
     LLVMRustDIBuilderRef Builder,
     const char *Filename, size_t FilenameLen,
     const char *Directory, size_t DirectoryLen, LLVMRustChecksumKind CSKind,
-    const char *Checksum, size_t ChecksumLen) {
+    const char *Checksum, size_t ChecksumLen,
+    const char *Source, size_t SourceLen) {
 
   std::optional<DIFile::ChecksumKind> llvmCSKind = fromRust(CSKind);
   std::optional<DIFile::ChecksumInfo<StringRef>> CSInfo{};
   if (llvmCSKind)
     CSInfo.emplace(*llvmCSKind, StringRef{Checksum, ChecksumLen});
+  std::optional<StringRef> oSource{};
+  if (Source)
+    oSource = StringRef(Source, SourceLen);
   return wrap(Builder->createFile(StringRef(Filename, FilenameLen),
                                   StringRef(Directory, DirectoryLen),
-                                  CSInfo));
+                                  CSInfo, oSource));
 }
 
 extern "C" LLVMMetadataRef

compiler/rustc_session/src/options.rs

@@ -1489,6 +1489,8 @@ options! {
         "import library generation tool (ignored except when targeting windows-gnu)"),
     embed_bitcode: bool = (true, parse_bool, [TRACKED],
         "emit bitcode in rlibs (default: yes)"),
+    embed_source: bool = (false, parse_bool, [TRACKED],
+        "embed source text in DWARF debug sections (default: no)"),
     extra_filename: String = (String::new(), parse_string, [UNTRACKED],
         "extra data to put in each output filename"),
     force_frame_pointers: FramePointer = (FramePointer::MayOmit, parse_frame_pointer, [TRACKED],

src/doc/rustc/src/codegen-options/index.md

@@ -146,6 +146,10 @@ at start-up, because the combination is invalid.
 > reason for that is that it's how it was for rustc 1.44 and prior. In 1.45 this
 > option was added to turn off what had always been the default.
 
+## embed-source
+
+TODO
+
 ## extra-filename
 
 This option allows you to put extra data in each output filename. It takes a