[Nios2] Subtarget, basic infrastructure for frame, instructions and registers

This is the second minimal patch keeping Nios2 target buildable.
I'm adding subtarget here and other stuff for frame lowering, instruction,
register information methods. I do not add any test cases, as still there
are missing parts like DAG selector and assembly printing. I plan to include
them into the next patch.

Patch by Andrei Grischenko <andrei.l.grischenko@intel.com>

Differential Revision: https://reviews.llvm.org/D37256

llvm-svn: 313626

1 files changed, 64 insertions, 9 deletions

diff --git a/llvm/lib/Target/Nios2/Nios2TargetMachine.cpp b/llvm/lib/Target/Nios2/Nios2TargetMachine.cpp
index 16d4eabcfaf..bea20d84846 100644
--- a/llvm/lib/Target/Nios2/Nios2TargetMachine.cpp
+++ b/llvm/lib/Target/Nios2/Nios2TargetMachine.cpp
@@ -14,22 +14,24 @@
 #include "Nios2TargetMachine.h"
 #include "Nios2.h"
 
+#include "llvm/CodeGen/TargetPassConfig.h"
+#include "llvm/Support/TargetRegistry.h"
+
 using namespace llvm;
 
 #define DEBUG_TYPE "nios2"
 
 extern "C" void LLVMInitializeNios2Target() {
   // Register the target.
+  RegisterTargetMachine<Nios2TargetMachine> X(getTheNios2Target());
 }
 
-static std::string computeDataLayout(const Triple &TT, StringRef CPU,
-                                     const TargetOptions &Options) {
+static std::string computeDataLayout() {
   return "e-p:32:32:32-i8:8:32-i16:16:32-n32";
 }
 
-static Reloc::Model getEffectiveRelocModel(CodeModel::Model CM,
-                                           Optional<Reloc::Model> RM) {
-  if (!RM.hasValue() || CM == CodeModel::JITDefault)
+static Reloc::Model getEffectiveRelocModel(Optional<Reloc::Model> RM) {
+  if (!RM.hasValue())
     return Reloc::Static;
   return *RM;
 }
@@ -38,9 +40,62 @@ Nios2TargetMachine::Nios2TargetMachine(const Target &T, const Triple &TT,
                                        StringRef CPU, StringRef FS,
                                        const TargetOptions &Options,
                                        Optional<Reloc::Model> RM,
-                                       CodeModel::Model CM,
-                                       CodeGenOpt::Level OL)
-    : LLVMTargetMachine(T, computeDataLayout(TT, CPU, Options), TT, CPU, FS,
-                        Options, getEffectiveRelocModel(CM, RM), CM, OL) {}
+                                       Optional<CodeModel::Model> CM,
+                                       CodeGenOpt::Level OL, bool JIT)
+    : LLVMTargetMachine(T, computeDataLayout(), TT, CPU, FS, Options,
+                        getEffectiveRelocModel(RM), *CM, OL),
+      DefaultSubtarget(TT, CPU, FS, *this) {}
 
 Nios2TargetMachine::~Nios2TargetMachine() {}
+
+const Nios2Subtarget *
+Nios2TargetMachine::getSubtargetImpl(const Function &F) const {
+  Attribute CPUAttr = F.getFnAttribute("target-cpu");
+  Attribute FSAttr = F.getFnAttribute("target-features");
+
+  std::string CPU = !CPUAttr.hasAttribute(Attribute::None)
+                        ? CPUAttr.getValueAsString().str()
+                        : TargetCPU;
+  std::string FS = !FSAttr.hasAttribute(Attribute::None)
+                       ? FSAttr.getValueAsString().str()
+                       : TargetFS;
+
+  auto &I = SubtargetMap[CPU + FS];
+  if (!I) {
+    // This needs to be done before we create a new subtarget since any
+    // creation will depend on the TM and the code generation flags on the
+    // function that reside in TargetOptions.
+    resetTargetOptions(F);
+    I = llvm::make_unique<Nios2Subtarget>(TargetTriple, CPU, FS, *this);
+  }
+  return I.get();
+}
+
+namespace {
+/// Nios2 Code Generator Pass Configuration Options.
+class Nios2PassConfig : public TargetPassConfig {
+public:
+  Nios2PassConfig(Nios2TargetMachine &TM, PassManagerBase *PM)
+      : TargetPassConfig(TM, *PM) {}
+
+  Nios2TargetMachine &getNios2TargetMachine() const {
+    return getTM<Nios2TargetMachine>();
+  }
+
+  const Nios2Subtarget &getNios2Subtarget() const {
+    return *getNios2TargetMachine().getSubtargetImpl();
+  }
+  void addCodeGenPrepare() override;
+  void addIRPasses() override;
+};
+} // namespace
+
+TargetPassConfig *Nios2TargetMachine::createPassConfig(PassManagerBase &PM) {
+  return new Nios2PassConfig(*this, &PM);
+}
+
+void Nios2PassConfig::addCodeGenPrepare() {
+  TargetPassConfig::addCodeGenPrepare();
+}
+
+void Nios2PassConfig::addIRPasses() { TargetPassConfig::addIRPasses(); }