First cut at the Code Generator using the TableGen methodology.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6321 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 128 insertions, 0 deletions

diff --git a/utils/TableGen/CodeEmitterGen.cpp b/utils/TableGen/CodeEmitterGen.cpp
new file mode 100644
index 0000000000..0d378871e8
--- /dev/null
+++ b/utils/TableGen/CodeEmitterGen.cpp
@@ -0,0 +1,105 @@
+#include "Record.h"
+#include "CodeEmitterGen.h"
+#include <ostream>
+
+void CodeEmitterGen::createEmitter(std::ostream &o) {
+  std::vector<Record*> Insts;
+
+  const std::map<std::string, Record*> &Defs = Records.getDefs();
+  Record *Inst = Records.getClass("Instruction");
+  assert(Inst && "Couldn't find Instruction class!");
+
+  for (std::map<std::string, Record*>::const_iterator I = Defs.begin(),
+	 E = Defs.end(); I != E; ++I)
+    if (I->second->isSubClassOf(Inst))
+      Insts.push_back(I->second);
+
+  std::string Namespace = "V9::";
+  std::string ClassName = "SparcV9CodeEmitter::";
+
+  //const std::string &Namespace = Inst->getValue("Namespace")->getName();
+  o << "unsigned " << ClassName
+    << "getBinaryCodeForInstr(MachineInstr &MI) {\n"
+    << "  unsigned Value = 0;\n"
+    << "  switch (MI.getOpcode()) {\n";
+  for (std::vector<Record*>::iterator I = Insts.begin(), E = Insts.end();
+       I != E; ++I)
+  {
+    Record *R = *I;
+    o << "    case " << Namespace << R->getName() << ": {\n";
+
+    const RecordVal *InstVal = R->getValue("Inst");
+    Init *InitVal = InstVal->getValue();
+
+    assert(dynamic_cast<BitsInit*>(InitVal) &&
+           "Can only handle undefined bits<> types!");
+    BitsInit *BI = (BitsInit*)InitVal;
+
+    unsigned Value = 0;
+    const std::vector<RecordVal> &Vals = R->getValues();
+
+    // Start by filling in fixed values...
+    for (unsigned i = 0, e = BI->getNumBits(); i != e; ++i)
+      if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(i)))
+        Value |= B->getValue() << i;
+
+    o << "      Value = " << Value << "U;\n";
+    o << "      // " << *InstVal << "\n";
+    
+    // Loop over all of the fields in the instruction adding in any
+    // contributions to this value (due to bit references).
+    //
+    unsigned Offset = 31, opNum=0;
+    std::map<const std::string,unsigned> OpOrder;
+    for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
+      if (Vals[i].getName() != "Inst" && 
+          !Vals[i].getValue()->isComplete() &&
+          Vals[i].getName() != "annul" && 
+          Vals[i].getName() != "cc" &&
+          Vals[i].getName() != "predict")
+      {
+        o << "      // " << opNum << ": " << Vals[i].getName() << "\n";
+        OpOrder[Vals[i].getName()] = opNum++;
+      }
+    }
+
+    for (int f = Vals.size()-1; f >= 0; --f) {
+      if (Vals[f].getPrefix()) {
+        BitsInit *FieldInitializer = (BitsInit*)Vals[f].getValue();
+
+        // Scan through the field looking for bit initializers of the current
+        // variable...
+        for (int i = FieldInitializer->getNumBits()-1; i >= 0; --i) {
+          
+          if (BitInit *BI=dynamic_cast<BitInit*>(FieldInitializer->getBit(i))){
+            --Offset;
+          } else if (UnsetInit *UI = 
+                     dynamic_cast<UnsetInit*>(FieldInitializer->getBit(i))) {
+            --Offset;
+          } else if (VarBitInit *VBI =
+                     dynamic_cast<VarBitInit*>(FieldInitializer->getBit(i))) {
+            TypedInit *TI = VBI->getVariable();
+            if (VarInit *VI = dynamic_cast<VarInit*>(TI)) {
+              o << "      Value |= getValueBit(MI.getOperand(" 
+                << OpOrder[VI->getName()]
+                << "), " << VBI->getBitNum()
+                << ")" << " << " << Offset << ";\n";
+              --Offset;
+            } else if (FieldInit *FI = dynamic_cast<FieldInit*>(TI)) {
+              // FIXME: implement this!
+              o << "FIELD INIT not implemented yet!\n";
+            } else {
+              o << "something else\n";
+            }
+          }
+        }
+      }
+    }
+
+    o << "      break;\n"
+      << "    }\n";
+  }
+  o << "  }\n"
+    << "  return Value;\n"
+    << "}\n";
+}
diff --git a/utils/TableGen/CodeEmitterGen.h b/utils/TableGen/CodeEmitterGen.h
new file mode 100644
index 0000000000..18ebcd4bd4
--- /dev/null
+++ b/utils/TableGen/CodeEmitterGen.h
@@ -0,0 +1,23 @@
+//===- CodeEmitterGen.h - Code Emitter Generator ----------------*- C++ -*-===//
+//
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CODEMITTERGEN_H
+#define CODEMITTERGEN_H
+
+#include "Record.h"
+#include <ostream>
+
+struct CodeEmitterGen {
+  RecordKeeper &Records;
+  
+public:
+  CodeEmitterGen(RecordKeeper &R) : Records(R) {}
+  
+  void createEmitter(std::ostream &o);
+  void emitMachineOpEmitter(std::ostream &o, const std::string &Namespace);
+  void emitGetValueBit(std::ostream &o, const std::string &Namespace);
+};
+
+#endif