[llvm-readobj/llvm-readelf] - Improve/cleanup the error reporting API.

urrently we have the following functions for error reporting:

--
LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg);
void reportError(Error Err, StringRef Input); 
void reportWarning(Twine Msg);
void reportWarning(StringRef Input, Error Err);
void warn(llvm::Error Err);
void error(std::error_code EC);
---

Problems are: naming is inconsistent, arguments order is inconsistent,
some of the functions looks excessive.

After applying this patch we have:

---
LLVM_ATTRIBUTE_NORETURN void reportError(Error Err, StringRef Input); 
LLVM_ATTRIBUTE_NORETURN void reportError(std::error_code EC, StringRef Input);
void reportWarning(Error Err, StringRef Input);
---

I'd be happy to remove reportError(std::error_code EC, StringRef Input) too, but it
is used by COFF heavily.

Test cases were updated, they show an improvement introduced.

Differential revision: https://reviews.llvm.org/D66286

llvm-svn: 369190

1 files changed, 19 insertions, 25 deletions

diff --git a/llvm/tools/llvm-readobj/llvm-readobj.cpp b/llvm/tools/llvm-readobj/llvm-readobj.cpp
index ec67bd5..8e89ccc 100644
--- a/llvm/tools/llvm-readobj/llvm-readobj.cpp
+++ b/llvm/tools/llvm-readobj/llvm-readobj.cpp
@@ -375,52 +375,46 @@ namespace opts {
 
 namespace llvm {
 
-LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg) {
+LLVM_ATTRIBUTE_NORETURN static void error(Twine Msg) {
+  // Flush the standard output to print the error at a
+  // proper place.
   fouts().flush();
   errs() << "\n";
   WithColor::error(errs()) << Msg << "\n";
   exit(1);
 }
 
-void reportError(Error Err, StringRef Input) {
+LLVM_ATTRIBUTE_NORETURN void reportError(Error Err, StringRef Input) {
   assert(Err);
   if (Input == "-")
     Input = "<stdin>";
   handleAllErrors(createFileError(Input, std::move(Err)),
-                  [&](const ErrorInfoBase &EI) { reportError(EI.message()); });
+                  [&](const ErrorInfoBase &EI) { error(EI.message()); });
+  llvm_unreachable("error() call should never return");
 }
 
-void reportWarning(Twine Msg) {
-  fouts().flush();
-  errs() << "\n";
-  WithColor::warning(errs()) << Msg << "\n";
-}
-
-void reportWarning(StringRef Input, Error Err) {
+void reportWarning(Error Err, StringRef Input) {
+  assert(Err);
   if (Input == "-")
     Input = "<stdin>";
-  warn(createFileError(Input, std::move(Err)));
-}
 
-void warn(Error Err) {
-  handleAllErrors(std::move(Err), [&](const ErrorInfoBase &EI) {
-    reportWarning(EI.message());
-  });
-}
-
-void error(std::error_code EC) {
-  if (!EC)
-    return;
-  reportError(EC.message());
+  handleAllErrors(createFileError(Input, std::move(Err)),
+                  [&](const ErrorInfoBase &EI) {
+                    // Flush the standard output to print the warning at a
+                    // proper place.
+                    fouts().flush();
+                    errs() << "\n";
+                    WithColor::warning(errs()) << EI.message() << "\n";
+                  });
 }
 
-} // namespace llvm
-
-static void reportError(std::error_code EC, StringRef Input) {
+LLVM_ATTRIBUTE_NORETURN void reportError(std::error_code EC, StringRef Input) {
   assert(EC != readobj_error::success);
   reportError(errorCodeToError(EC), Input);
 }
 
+} // namespace llvm
+
 static bool isMipsArch(unsigned Arch) {
   switch (Arch) {
   case llvm::Triple::mips: