[llvm-mc] Add -M to replace -riscv-no-aliases and -riscv-arch-reg-names

In objdump, many targets support `-M no-aliases`.  Instead of having a
`-*-no-aliases` for each target when LLVM adds the support, it makes more sense
to introduce objdump style `-M`.

-riscv-arch-reg-names is removed. -riscv-no-aliases has too many uses and thus is retained for now.

Reviewed By: luismarques

Differential Revision: https://reviews.llvm.org/D103004

1 files changed, 9 insertions, 0 deletions

diff --git a/llvm/tools/llvm-mc/llvm-mc.cpp b/llvm/tools/llvm-mc/llvm-mc.cpp
index 73a3a05..71940a7 100644
--- a/llvm/tools/llvm-mc/llvm-mc.cpp
+++ b/llvm/tools/llvm-mc/llvm-mc.cpp
@@ -46,6 +46,9 @@ static mc::RegisterMCTargetOptionsFlags MOF;
 static cl::opt<std::string>
 InputFilename(cl::Positional, cl::desc("<input file>"), cl::init("-"));
 
+static cl::list<std::string>
+    DisassemblerOptions("M", cl::desc("Disassembler options"));
+
 static cl::opt<std::string> OutputFilename("o", cl::desc("Output filename"),
                                            cl::value_desc("filename"),
                                            cl::init("-"));
@@ -496,6 +499,12 @@ int main(int argc, char **argv) {
       return 1;
     }
 
+    for (StringRef Opt : DisassemblerOptions)
+      if (!IP->applyTargetSpecificCLOption(Opt)) {
+        WithColor::error() << "invalid disassembler option '" << Opt << "'\n";
+        return 1;
+      }
+
     // Set the display preference for hex vs. decimal immediates.
     IP->setPrintImmHex(PrintImmHex);