[llvm-branch-commits] [Remarks] BitstreamRemarkParser: Refactor error handling (PR #156511)

[Florian Hahn via llvm-branch-commits]

================
@@ -12,35 +12,75 @@
 //===----------------------------------------------------------------------===//
 
 #include "BitstreamRemarkParser.h"
-#include "llvm/Remarks/Remark.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Path.h"
+#include <cassert>
 #include <optional>
 
 using namespace llvm;
 using namespace llvm::remarks;
 
-static Error unknownRecord(const char *BlockName, unsigned RecordID) {
-  return createStringError(
-      std::make_error_code(std::errc::illegal_byte_sequence),
-      "Error while parsing %s: unknown record entry (%lu).", BlockName,
-      RecordID);
+namespace {
+
+template <typename... Ts> Error error(char const *Fmt, const Ts &...Vals) {
+  std::string Buffer;
+  raw_string_ostream OS(Buffer);
+  OS << formatv(Fmt, Vals...);
+  return make_error<StringError>(
+      Buffer, std::make_error_code(std::errc::illegal_byte_sequence));
+}
+
+} // namespace
+
+Error BitstreamBlockParserHelperBase::unknownRecord(unsigned AbbrevID) {
+  return error("Unknown record entry ({}).", AbbrevID);
 }
 
-static Error malformedRecord(const char *BlockName, const char *RecordName) {
-  return createStringError(
-      std::make_error_code(std::errc::illegal_byte_sequence),
-      "Error while parsing %s: malformed record entry (%s).", BlockName,
-      RecordName);
+Error BitstreamBlockParserHelperBase::unexpectedRecord(StringRef RecordName) {
+  return error("Unexpected record entry ({}).", RecordName);
 }
 
-BitstreamMetaParserHelper::BitstreamMetaParserHelper(
-    BitstreamCursor &Stream, BitstreamBlockInfo &BlockInfo)
-    : Stream(Stream), BlockInfo(BlockInfo) {}
+Error BitstreamBlockParserHelperBase::malformedRecord(StringRef RecordName) {
+  return error("Malformed record entry ({}).", RecordName);
+}
+
+Error BitstreamBlockParserHelperBase::unexpectedBlock(unsigned Code) {
+  return error("Unexpected subblock ({}).", Code);
+}
+
+static Expected<unsigned> expectSubBlock(BitstreamCursor &Stream) {
+  Expected<BitstreamEntry> Next = Stream.advance();
+  if (!Next)
+    return Next.takeError();
+  switch (Next->Kind) {
+  case BitstreamEntry::SubBlock:
+    return Next->ID;
+  case BitstreamEntry::Record:
+  case BitstreamEntry::EndBlock:
+    return error("Expected subblock, but got unexpected record.");
+  case BitstreamEntry::Error:
+    return error("Expected subblock, but got unexpected end of bitstream.");
+  }
+}
+
+Error BitstreamBlockParserHelperBase::expectBlock() {
+  auto MaybeBlockID = expectSubBlock(Stream);
+  if (!MaybeBlockID)
+    return MaybeBlockID.takeError();
+  if (*MaybeBlockID != BlockID)
+    return error("Expected {} block, but got unexpected block ({}).", BlockName,
+                 *MaybeBlockID);
+  return Error::success();
+}
+
+Error BitstreamBlockParserHelperBase::enterBlock() {
+  if (Stream.EnterSubBlock(BlockID))
+    return error("Error while entering {} block.", BlockName);
+  return Error::success();
+}
 
 /// Parse a record and fill in the fields in the parser.
----------------
fhahn wrote:

move comment to declaration?

https://github.com/llvm/llvm-project/pull/156511