[yaml2obj] Add new command line option `-docnum`.

Input YAML file might contain multiple object file definitions.
New option `-docnum` allows to specify an ordinal number (starting from 1)
of definition used for an object file generation.

Patch reviewed by Sean Silva.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209967 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 37 insertions, 12 deletions

diff --git a/tools/yaml2obj/yaml2coff.cpp b/tools/yaml2obj/yaml2coff.cpp
index a0ede246bd..c772db9a8e 100644
--- a/tools/yaml2obj/yaml2coff.cpp
+++ b/tools/yaml2obj/yaml2coff.cpp
@@ -327,8 +327,7 @@ bool writeCOFF(COFFParser &CP, raw_ostream &OS) {
   return true;
 }
 
-int yaml2coff(llvm::raw_ostream &Out, llvm::MemoryBuffer *Buf) {
-  yaml::Input YIn(Buf->getBuffer());
+int yaml2coff(yaml::Input &YIn, raw_ostream &Out) {
   COFFYAML::Object Doc;
   YIn >> Doc;
   if (YIn.error()) {
diff --git a/tools/yaml2obj/yaml2elf.cpp b/tools/yaml2obj/yaml2elf.cpp
index bb52cda7c1..11a56469b0 100644
--- a/tools/yaml2obj/yaml2elf.cpp
+++ b/tools/yaml2obj/yaml2elf.cpp
@@ -467,8 +467,7 @@ static bool isLittleEndian(const ELFYAML::Object &Doc) {
   return Doc.Header.Data == ELFYAML::ELF_ELFDATA(ELF::ELFDATA2LSB);
 }
 
-int yaml2elf(llvm::raw_ostream &Out, llvm::MemoryBuffer *Buf) {
-  yaml::Input YIn(Buf->getBuffer());
+int yaml2elf(yaml::Input &YIn, raw_ostream &Out) {
   ELFYAML::Object Doc;
   YIn >> Doc;
   if (YIn.error()) {
diff --git a/tools/yaml2obj/yaml2obj.cpp b/tools/yaml2obj/yaml2obj.cpp
index 2493b48699..eef9c841f3 100644
--- a/tools/yaml2obj/yaml2obj.cpp
+++ b/tools/yaml2obj/yaml2obj.cpp
@@ -15,6 +15,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "yaml2obj.h"
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/ManagedStatic.h"
@@ -24,6 +25,7 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/system_error.h"
 #include "llvm/Support/ToolOutputFile.h"
+#include "llvm/Support/YAMLTraits.h"
 
 using namespace llvm;
 
@@ -51,9 +53,27 @@ cl::opt<YAMLObjectFormat> Format(
     clEnumValN(YOF_ELF, "elf", "ELF object file format"),
   clEnumValEnd));
 
+cl::opt<unsigned>
+DocNum("docnum", cl::init(1),
+       cl::desc("Read specified document from input (default = 1)"));
+
 static cl::opt<std::string> OutputFilename("o", cl::desc("Output filename"),
                                            cl::value_desc("filename"));
 
+typedef int (*ConvertFuncPtr)(yaml::Input & YIn, raw_ostream &Out);
+
+int convertYAML(yaml::Input & YIn, raw_ostream &Out, ConvertFuncPtr Convert) {
+  unsigned CurDocNum = 0;
+  do {
+    if (++CurDocNum == DocNum)
+      return Convert(YIn, Out);
+  } while (YIn.nextDocument());
+
+  errs() << "yaml2obj: Cannot find the " << DocNum
+         << llvm::getOrdinalSuffix(DocNum) << " document\n";
+  return 1;
+}
+
 int main(int argc, char **argv) {
   cl::ParseCommandLineOptions(argc, argv);
   sys::PrintStackTraceOnErrorSignal();
@@ -75,14 +95,19 @@ int main(int argc, char **argv) {
   if (MemoryBuffer::getFileOrSTDIN(Input, Buf))
     return 1;
 
-  int Res = 1;
+  ConvertFuncPtr Convert = nullptr;
   if (Format == YOF_COFF)
-    Res = yaml2coff(Out->os(), Buf.get());
+    Convert = yaml2coff;
   else if (Format == YOF_ELF)
-    Res = yaml2elf(Out->os(), Buf.get());
-  else
+    Convert = yaml2elf;
+  else {
     errs() << "Not yet implemented\n";
+    return 1;
+  }
+
+  yaml::Input YIn(Buf->getBuffer());
 
+  int Res = convertYAML(YIn, Out->os(), Convert);
   if (Res == 0)
     Out->keep();
 
diff --git a/tools/yaml2obj/yaml2obj.h b/tools/yaml2obj/yaml2obj.h
index 095435c549..086f6413aa 100644
--- a/tools/yaml2obj/yaml2obj.h
+++ b/tools/yaml2obj/yaml2obj.h
@@ -13,10 +13,12 @@
 #define LLVM_TOOLS_YAML2OBJ_H
 
 namespace llvm {
-  class raw_ostream;
-  class MemoryBuffer;
+class raw_ostream;
+namespace yaml {
+class Input;
 }
-int yaml2coff(llvm::raw_ostream &Out, llvm::MemoryBuffer *Buf);
-int yaml2elf(llvm::raw_ostream &Out, llvm::MemoryBuffer *Buf);
+}
+int yaml2coff(llvm::yaml::Input &YIn, llvm::raw_ostream &Out);
+int yaml2elf(llvm::yaml::Input &YIn, llvm::raw_ostream &Out);
 
 #endif