[llvm-remarkutil] Auto-detect serializer format based on file extension

If serializer format is set to Auto, try to detect user intent based on
the file extension of the output file name.

Pull Request: llvm#160545

Author: tobias-stadler

llvm/test/tools/llvm-remarkutil/filter.test

@@ -18,9 +18,19 @@ RUN: llvm-remarkutil filter --remark-type=analysis %p/Inputs/filter.yaml | FileC
 
 RUN: llvm-remarkutil yaml2bitstream -o %t.opt.bitstream %p/Inputs/filter.yaml
 RUN: llvm-remarkutil filter --function=func1 %t.opt.bitstream | FileCheck %s --strict-whitespace --check-prefix=REMARK1
+RUN: llvm-remarkutil filter --function=func1 %t.opt.bitstream -o %t.r1.yamL
+RUN: cat %t.r1.yamL | FileCheck %s --strict-whitespace --check-prefix=REMARK1
+RUN: llvm-remarkutil filter --function=func1 %t.opt.bitstream -o %t.r1.yMl
+RUN: cat %t.r1.yMl | FileCheck %s --strict-whitespace --check-prefix=REMARK1
+RUN: llvm-remarkutil filter --function=func1 %t.opt.bitstream --serializer=yaml -o %t.r1.fake.opt.bitstream
+RUN: cat %t.r1.fake.opt.bitstream | FileCheck %s --strict-whitespace --check-prefix=REMARK1
 
 RUN: llvm-remarkutil filter --function=func1 %t.opt.bitstream -o %t.r1.opt.bitstream
 RUN: llvm-remarkutil bitstream2yaml %t.r1.opt.bitstream | FileCheck %s --strict-whitespace --check-prefix=REMARK1
+RUN: llvm-remarkutil filter --function=func1 %t.opt.bitstream -o %t.r1
+RUN: llvm-remarkutil bitstream2yaml %t.r1 | FileCheck %s --strict-whitespace --check-prefix=REMARK1
+RUN: llvm-remarkutil filter --function=func1 %p/Inputs/filter.yaml --serializer=bitstream -o %t.r1.fake.yaml
+RUN: llvm-remarkutil bitstream2yaml %t.r1.fake.yaml | FileCheck %s --strict-whitespace --check-prefix=REMARK1
 
 RUN: llvm-remarkutil filter --function=func %p/Inputs/filter.yaml | FileCheck %s --allow-empty --strict-whitespace --check-prefix=EMPTY
 

llvm/tools/llvm-remarkutil/RemarkFilter.cpp

@@ -46,12 +46,8 @@ static Error tryFilter() {
     return MaybeParser.takeError();
   auto &Parser = **MaybeParser;
 
-  Format SerializerFormat = OutputFormat;
-  if (SerializerFormat == Format::Auto) {
-    SerializerFormat = Parser.ParserFormat;
-    if (OutputFileName.empty() || OutputFileName == "-")
-      SerializerFormat = Format::YAML;
-  }
+  Format SerializerFormat =
+      getSerializerFormat(OutputFileName, OutputFormat, Parser.ParserFormat);
 
   auto MaybeOF = getOutputFileForRemarks(OutputFileName, SerializerFormat);
   if (!MaybeOF)

llvm/tools/llvm-remarkutil/RemarkUtilHelpers.cpp

@@ -54,6 +54,20 @@ getOutputFileForRemarks(StringRef OutputFileName, Format OutputFormat) {
                                                     : sys::fs::OF_None);
 }
 
+Format getSerializerFormat(StringRef OutputFileName, Format SelectedFormat,
+                           Format DefaultFormat) {
+  if (SelectedFormat != Format::Auto)
+    return SelectedFormat;
+  SelectedFormat = DefaultFormat;
+  if (OutputFileName.empty() || OutputFileName == "-" ||
+      OutputFileName.ends_with_insensitive(".yaml") ||
+      OutputFileName.ends_with_insensitive(".yml"))
+    SelectedFormat = Format::YAML;
+  if (OutputFileName.ends_with_insensitive(".bitstream"))
+    SelectedFormat = Format::Bitstream;
+  return SelectedFormat;
+}
+
 Expected<FilterMatcher>
 FilterMatcher::createRE(const llvm::cl::opt<std::string> &Arg) {
   return createRE(Arg.ArgStr, Arg);

llvm/tools/llvm-remarkutil/RemarkUtilHelpers.h

@@ -47,7 +47,8 @@
       "serializer", cl::init(Format::Auto),                                    \
       cl::desc("Output remark format to serialize"),                           \
       cl::values(clEnumValN(Format::Auto, "auto",                              \
-                            "Follow the parser format (default)"),             \
+                            "Automatic detection based on output file "        \
+                            "extension or parser format (default)"),           \
                  clEnumValN(Format::YAML, "yaml", "YAML"),                     \
                  clEnumValN(Format::Bitstream, "bitstream", "Bitstream")),     \
       cl::sub(SUBOPT));
@@ -151,6 +152,12 @@ getOutputFileWithFlags(StringRef OutputFileName, sys::fs::OpenFlags Flags);
 Expected<std::unique_ptr<ToolOutputFile>>
 getOutputFileForRemarks(StringRef OutputFileName, Format OutputFormat);
 
+/// Choose the serializer format. If \p SelectedFormat is Format::Auto, try to
+/// detect the format based on the extension of \p OutputFileName or fall back
+/// to \p DefaultFormat.
+Format getSerializerFormat(StringRef OutputFileName, Format SelectedFormat,
+                           Format DefaultFormat);
+
 /// Filter object which can be either a string or a regex to match with the
 /// remark properties.
 class FilterMatcher {