[Hexagon] Add -mv.. options to override CPU selection

This is for compatibility with scripts that use -mv5, etc. with the
assembler.

llvm-svn: 266918

1 files changed, 39 insertions, 3 deletions

diff --git a/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCTargetDesc.cpp b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCTargetDesc.cpp
index 9a292577a8f..7997198c7ac 100644
--- a/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCTargetDesc.cpp
+++ b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCTargetDesc.cpp
@@ -48,10 +48,46 @@ cl::opt<bool> llvm::HexagonDisableDuplex
   ("mno-pairing",
    cl::desc("Disable looking for duplex instructions for Hexagon"));
 
+static cl::opt<bool> HexagonV4ArchVariant("mv4", cl::Hidden, cl::init(false),
+  cl::desc("Build for Hexagon V4"));
+
+static cl::opt<bool> HexagonV5ArchVariant("mv5", cl::Hidden, cl::init(false),
+  cl::desc("Build for Hexagon V5"));
+
+static cl::opt<bool> HexagonV55ArchVariant("mv55", cl::Hidden, cl::init(false),
+  cl::desc("Build for Hexagon V55"));
+
+static cl::opt<bool> HexagonV60ArchVariant("mv60", cl::Hidden, cl::init(false),
+  cl::desc("Build for Hexagon V60"));
+
+
+static StringRef DefaultArch = "hexagonv60";
+
+static StringRef HexagonGetArchVariant() {
+  if (HexagonV4ArchVariant)
+    return "hexagonv4";
+  if (HexagonV5ArchVariant)
+    return "hexagonv5";
+  if (HexagonV55ArchVariant)
+    return "hexagonv55";
+  if (HexagonV60ArchVariant)
+    return "hexagonv60";
+  return "";
+}
+
 StringRef HEXAGON_MC::selectHexagonCPU(const Triple &TT, StringRef CPU) {
-  if (CPU.empty())
-    CPU = "hexagonv60";
-  return CPU;
+  StringRef ArchV = HexagonGetArchVariant();
+  if (!ArchV.empty() && !CPU.empty()) {
+    if (ArchV != CPU)
+      report_fatal_error("conflicting architectures specified.");
+    return CPU;
+  }
+  if (ArchV.empty()) {
+    if (CPU.empty())
+      CPU = DefaultArch;
+    return CPU;
+  }
+  return ArchV;
 }
 
 MCInstrInfo *llvm::createHexagonMCInstrInfo() {