Merge pull request #40 from oureveryday/main

Implement movsq
NaC-L · Oct 18, 2024 · 3e8c18d · 3e8c18d
2 parents e10640c + ecbf49a
commit 3e8c18d
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Showing 3 changed files with 27 additions and 42 deletions.
diff --git a/lifter/OperandUtils.cpp b/lifter/OperandUtils.cpp
@@ -1147,8 +1147,7 @@ Value* lifterClass::setFlag(const Flag flag, Value* newValue) {
   LLVMContext& context = builder.getContext();
   newValue = createTruncFolder(newValue, Type::getInt1Ty(context));
   printvalue2((int32_t)flag) printvalue(newValue);
-  if (flag == FLAG_RESERVED1 || flag == FLAG_RESERVED5 || flag == FLAG_IF ||
-      flag == FLAG_DF)
+  if (flag == FLAG_RESERVED1 || flag == FLAG_RESERVED5 || flag == FLAG_IF)
     return nullptr;
 
   FlagList[flag].set(newValue); // Set the new value directly
@@ -1158,8 +1157,7 @@ Value* lifterClass::setFlag(const Flag flag, Value* newValue) {
 void lifterClass::setFlag(const Flag flag,
                           std::function<Value*()> calculation) {
   // If the flag is one of the reserved ones, do not modify
-  if (flag == FLAG_RESERVED1 || flag == FLAG_RESERVED5 || flag == FLAG_IF ||
-      flag == FLAG_DF)
+  if (flag == FLAG_RESERVED1 || flag == FLAG_RESERVED5 || flag == FLAG_IF)
     return;
 
   // lazy calculation

diff --git a/lifter/Semantics.cpp b/lifter/Semantics.cpp
@@ -259,76 +259,60 @@ void lifterClass::branchHelper(Value* condition, const string& instname,
   // cout << "pathInfo:" << pathInfo << " dest: " << destination  <<
   // "\n";
 }
-
-void lifterClass::lift_movsb() {
+void lifterClass::lift_movs_X() {
+  LLVMContext& context = builder.getContext();
+  // Get the size based on the operand
+  int size = operands[1].size;
 
   // DEST := SRC;
-  // [esi] = [edi]
+  // Parameterize size and direction
   // sign = DF (-1/+1)
-  // incdecv = size*sign (sb means size is 1)
-  // esi += incdecv
-  // edi += incdecv
-  //
-
-  // Value* SRCptrvalue =
-  // GetOperandValue(operands[0],operands[0].size);
-
-  Value* DSTptrvalue = GetOperandValue(operands[1], operands[1].size);
+  // incdecv = size*sign
 
+  Value* DSTptrvalue = GetOperandValue(operands[1], size);
   SetOperandValue(operands[0], DSTptrvalue);
 
   bool isREP = (instruction.attributes & ZYDIS_ATTRIB_HAS_REP) != 0;
 
   Value* DF = getFlag(FLAG_DF);
-  auto one = ConstantInt::get(DF->getType(), 1);
-  // sign = (x*(x+1)) - 1
-  // v = sign * bytesize ; bytesize is 1
 
-  Value* Direction =
-      createSubFolder(createMulFolder(DF, createAddFolder(DF, one)), one);
+  // sign = (DF*(DF+1)) - 1
+  // v = sign * byteSize
+
+  auto byteSizeValue = size;
 
   auto SRCop = operands[2 + isREP];
   auto DSTop = operands[3 + isREP];
-
+  printvalue(DF);
+  Value* Direction = createSelectFolder(DF, ConstantInt::get(Type::getIntNTy(context, SRCop.size),1 * byteSizeValue),
+      ConstantInt::get(Type::getIntNTy(context, SRCop.size),-1 * byteSizeValue));
+  printvalue(Direction);
+
   Value* SRCvalue = GetOperandValue(SRCop, SRCop.size);
   Value* DSTvalue = GetOperandValue(DSTop, DSTop.size);
 
   if (isREP) {
-    // if REP, operands[1] will be e/rax
-    // in that case, repeat and decrement e/rax until its 0
-
-    // we can create a loop but I dont know how that would effect our
-    // optimizations
     Value* count = GetOperandValue(operands[2], operands[2].size);
     if (auto countci = dyn_cast<ConstantInt>(count)) {
       Value* UpdateSRCvalue = SRCvalue;
       Value* UpdateDSTvalue = DSTvalue;
       uint64_t looptime = countci->getZExtValue();
-      printvalue2(looptime);
 
       for (int i = looptime; i > 0; i--) {
-        // TODO: fix this loop
-
-        // Value* SRCptrvalue = GetOperandValue(
-        // operands[0],
-        // operands[0].size);
-        DSTptrvalue = GetOperandValue(operands[1], operands[1].size);
-
+        DSTptrvalue = GetOperandValue(operands[1], size);
         SetOperandValue(operands[0], DSTptrvalue);
 
         UpdateSRCvalue = createAddFolder(UpdateSRCvalue, Direction);
         UpdateDSTvalue = createAddFolder(UpdateDSTvalue, Direction);
-        printvalue(UpdateDSTvalue) printvalue(UpdateSRCvalue);
 
         SetOperandValue(SRCop, UpdateSRCvalue);
         SetOperandValue(DSTop, UpdateDSTvalue);
-        // bad cheat
+
         if (i > 1)
           debugging::increaseInstCounter();
       }
 
       SetOperandValue(operands[2], ConstantInt::get(count->getType(), 0));
-
       return;
     } else {
       UNREACHABLE("fix rep");
@@ -341,6 +325,7 @@ void lifterClass::lift_movsb() {
   SetOperandValue(SRCop, UpdateSRCvalue);
   SetOperandValue(DSTop, UpdateDSTvalue);
 }
+
 void lifterClass::lift_movaps() {
   auto dest = operands[0];
   auto src = operands[1];
@@ -3669,11 +3654,13 @@ void lifterClass::liftInstructionSemantics() {
     lift_mov();
     break;
   }
-  case ZYDIS_MNEMONIC_MOVSB: {
-    lift_movsb();
+  case ZYDIS_MNEMONIC_MOVSB:
+  case ZYDIS_MNEMONIC_MOVSW:
+  case ZYDIS_MNEMONIC_MOVSD:
+  case ZYDIS_MNEMONIC_MOVSQ: {
+    lift_movs_X();
     break;
   }
-
     // cmov
   case ZYDIS_MNEMONIC_CMOVZ: {
     lift_cmovz();

diff --git a/lifter/lifterClass.h b/lifter/lifterClass.h
@@ -408,7 +408,7 @@ class lifterClass {
   // end folders
 
   // semantics definition
-  DEFINE_FUNCTION(movsb);
+  DEFINE_FUNCTION(movs_X);
   DEFINE_FUNCTION(movaps);
   DEFINE_FUNCTION(mov);
   DEFINE_FUNCTION(cmovbz);