[llvm-exegesis][NFC] Simplify LLVMState.

Summary: Pretty much everything we need is in llvm::TargetMachine.

Reviewers: gchatelet

Subscribers: llvm-commits, tschuett

Differential Revision: https://reviews.llvm.org/D48428

llvm-svn: 335237
diff --git a/llvm/tools/llvm-exegesis/lib/LlvmState.cpp b/llvm/tools/llvm-exegesis/lib/LlvmState.cpp
index e286853..efb5c83 100644
--- a/llvm/tools/llvm-exegesis/lib/LlvmState.cpp
+++ b/llvm/tools/llvm-exegesis/lib/LlvmState.cpp
@@ -20,16 +20,15 @@
 
 namespace exegesis {
 
-LLVMState::LLVMState(const std::string &Triple, const std::string &CpuName)
-    : TheTriple(Triple), CpuName(CpuName) {
+LLVMState::LLVMState(const std::string &Triple, const std::string &CpuName) {
   std::string Error;
-  TheTarget = llvm::TargetRegistry::lookupTarget(TheTriple, Error);
+  const llvm::Target *const TheTarget =
+      llvm::TargetRegistry::lookupTarget(Triple, Error);
   assert(TheTarget && "unknown target for host");
-  SubtargetInfo.reset(
-      TheTarget->createMCSubtargetInfo(TheTriple, CpuName, Features));
-  InstrInfo.reset(TheTarget->createMCInstrInfo());
-  RegInfo.reset(TheTarget->createMCRegInfo(TheTriple));
-  AsmInfo.reset(TheTarget->createMCAsmInfo(*RegInfo, TheTriple));
+  const llvm::TargetOptions Options;
+  TargetMachine.reset(static_cast<llvm::LLVMTargetMachine *>(
+      TheTarget->createTargetMachine(Triple, CpuName, /*Features*/ "", Options,
+                                     llvm::Reloc::Model::Static)));
 }
 
 LLVMState::LLVMState()
@@ -38,21 +37,28 @@
 
 std::unique_ptr<llvm::LLVMTargetMachine>
 LLVMState::createTargetMachine() const {
-  const llvm::TargetOptions Options;
   return std::unique_ptr<llvm::LLVMTargetMachine>(
-      static_cast<llvm::LLVMTargetMachine *>(TheTarget->createTargetMachine(
-          TheTriple, CpuName, Features, Options, llvm::Reloc::Model::Static)));
+      static_cast<llvm::LLVMTargetMachine *>(
+          TargetMachine->getTarget().createTargetMachine(
+              TargetMachine->getTargetTriple().normalize(),
+              TargetMachine->getTargetCPU(),
+              TargetMachine->getTargetFeatureString(), TargetMachine->Options,
+              llvm::Reloc::Model::Static)));
 }
 
 bool LLVMState::canAssemble(const llvm::MCInst &Inst) const {
   llvm::MCObjectFileInfo ObjectFileInfo;
-  llvm::MCContext Context(AsmInfo.get(), RegInfo.get(), &ObjectFileInfo);
+  llvm::MCContext Context(TargetMachine->getMCAsmInfo(),
+                          TargetMachine->getMCRegisterInfo(), &ObjectFileInfo);
   std::unique_ptr<const llvm::MCCodeEmitter> CodeEmitter(
-      TheTarget->createMCCodeEmitter(*InstrInfo, *RegInfo, Context));
+      TargetMachine->getTarget().createMCCodeEmitter(
+          *TargetMachine->getMCInstrInfo(), *TargetMachine->getMCRegisterInfo(),
+          Context));
   llvm::SmallVector<char, 16> Tmp;
   llvm::raw_svector_ostream OS(Tmp);
   llvm::SmallVector<llvm::MCFixup, 4> Fixups;
-  CodeEmitter->encodeInstruction(Inst, OS, Fixups, *SubtargetInfo);
+  CodeEmitter->encodeInstruction(Inst, OS, Fixups,
+                                 *TargetMachine->getMCSubtargetInfo());
   return Tmp.size() > 0;
 }