Move all the code that creates code generation passes from Sparc.cpp to

TargetMachine.cpp, since it is entirely machine-independent.
Also, add options to disable optional back-end passes (preselection and
instr. scheduling).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3740 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/TargetMachine.cpp

@@ -8,8 +8,30 @@
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/MachineInstrInfo.h"
 #include "llvm/Target/MachineCacheInfo.h"
+#include "llvm/CodeGen/PreSelection.h"
+#include "llvm/CodeGen/InstrSelection.h"
+#include "llvm/CodeGen/InstrScheduling.h"
+#include "llvm/CodeGen/RegisterAllocation.h"
+#include "llvm/CodeGen/MachineCodeForMethod.h"
+#include "llvm/CodeGen/MachineCodeForInstruction.h"
+#include "llvm/Reoptimizer/Mapping/MappingInfo.h" 
+#include "llvm/Reoptimizer/Mapping/FInfo.h" 
+#include "llvm/Transforms/Scalar.h"
+#include "Support/CommandLine.h"
+#include "llvm/PassManager.h"
+#include "llvm/Function.h"
 #include "llvm/DerivedTypes.h"
 
+//---------------------------------------------------------------------------
+// Command line options to control choice of code generation passes.
+//---------------------------------------------------------------------------
+
+static cl::opt<bool> DisablePreSelect("nopreselect",
+                                      cl::desc("Disable preselection pass"));
+
+static cl::opt<bool> DisableSched("nosched",
+                                  cl::desc("Disable local scheduling pass"));
+
 //---------------------------------------------------------------------------
 // class TargetMachine
 // 
@@ -44,6 +66,99 @@ TargetMachine::findOptimalStorageSize(const Type* ty) const
 }
 
 
+//===---------------------------------------------------------------------===//
+// Default code generation passes.
+// 
+// Native code generation for a specified target.
+//===---------------------------------------------------------------------===//
+
+class ConstructMachineCodeForFunction : public FunctionPass {
+  TargetMachine &Target;
+public:
+  inline ConstructMachineCodeForFunction(TargetMachine &T) : Target(T) {}
+
+  const char *getPassName() const {
+    return "ConstructMachineCodeForFunction";
+  }
+
+  bool runOnFunction(Function &F) {
+    MachineCodeForMethod::construct(&F, Target);
+    return false;
+  }
+};
+
+struct FreeMachineCodeForFunction : public FunctionPass {
+  const char *getPassName() const { return "FreeMachineCodeForFunction"; }
+
+  static void freeMachineCode(Instruction &I) {
+    MachineCodeForInstruction::destroy(&I);
+  }
+  
+  bool runOnFunction(Function &F) {
+    for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
+      for (BasicBlock::iterator I = FI->begin(), E = FI->end(); I != E; ++I)
+        MachineCodeForInstruction::get(I).dropAllReferences();
+    
+    for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
+      for_each(FI->begin(), FI->end(), freeMachineCode);
+    
+    return false;
+  }
+};
+
+// addPassesToEmitAssembly - This method controls the entire code generation
+// process for the ultra sparc.
+//
+void
+TargetMachine::addPassesToEmitAssembly(PassManager &PM, std::ostream &Out)
+{
+  // Construct and initialize the MachineCodeForMethod object for this fn.
+  PM.add(new ConstructMachineCodeForFunction(*this));
+
+  // Specialize LLVM code for this target machine and then
+  // run basic dataflow optimizations on LLVM code.
+  if (!DisablePreSelect)
+    {
+      PM.add(createPreSelectionPass(*this));
+      PM.add(createReassociatePass());
+      PM.add(createGCSEPass());
+      PM.add(createLICMPass());
+    }
+
+  PM.add(createInstructionSelectionPass(*this));
+
+  if (!DisableSched)
+    PM.add(createInstructionSchedulingWithSSAPass(*this));
+
+  PM.add(getRegisterAllocator(*this));
+
+  //PM.add(new OptimizeLeafProcedures());
+  //PM.add(new DeleteFallThroughBranches());
+  //PM.add(new RemoveChainedBranches());    // should be folded with previous
+  //PM.add(new RemoveRedundantOps());       // operations with %g0, NOP, etc.
+
+  PM.add(getPrologEpilogInsertionPass());
+
+  PM.add(MappingInfoForFunction(Out));  
+
+  // Output assembly language to the .s file.  Assembly emission is split into
+  // two parts: Function output and Global value output.  This is because
+  // function output is pipelined with all of the rest of code generation stuff,
+  // allowing machine code representations for functions to be free'd after the
+  // function has been emitted.
+  //
+  PM.add(getFunctionAsmPrinterPass(Out));
+  PM.add(new FreeMachineCodeForFunction());  // Free stuff no longer needed
+
+  // Emit Module level assembly after all of the functions have been processed.
+  PM.add(getModuleAsmPrinterPass(Out));
+
+  // Emit bytecode to the assembly file into its special section next
+  PM.add(getEmitBytecodeToAsmPass(Out));
+  PM.add(getFunctionInfo(Out)); 
+}
+
+
 //---------------------------------------------------------------------------
 // class MachineInstructionInfo
 //	Interface to description of machine instructions
@@ -79,6 +194,10 @@ MachineInstrInfo::constantFitsInImmedField(MachineOpCode opCode,
   uint64_t maxImmedValue = maxImmedConstant(opCode, isSignExtended);
   if (maxImmedValue != 0)
     {
+      // NEED TO HANDLE UNSIGNED VALUES SINCE THEY MAY BECOME MUCH
+      // SMALLER AFTER CASTING TO SIGN-EXTENDED int, short, or char.
+      // See CreateUIntSetInstruction in SparcInstrInfo.cpp.
+      
       // Now check if the constant fits
       if (intValue <= (int64_t) maxImmedValue &&
 	  intValue >= -((int64_t) maxImmedValue+1))