// 1. a_2 = a_1 >> 1
// 2. C_2 = cond(a_2)
// 3. b_2 = b_1 rorc 1, C
// 4. flags_3 = cond(b_2)
// 1. tmp_1 = a_1
// 3. tmp_2 = b_2
// *. tmp_3 = (tmp1:tmp2) >> 1
// 1'. a_2 = slice(tmp3,16)
// 2'. b_2 = (cast) tmp3
// 4. flags_3 = cond(b_2)
private Instruction TransformRorC(Application rorc, Assignment a)
{
var sidOrigLo = ssaIds[a.Dst];
var sidCarry = ssaIds[(Identifier)rorc.Arguments[2]];
var cond = sidCarry.DefExpression as ConditionOf;
if (cond == null)
{
return(a);
}
var condId = cond.Expression as Identifier;
if (condId == null)
{
return(a);
}
var sidOrigHi = ssaIds[condId];
var shift = sidOrigHi.DefExpression as BinaryExpression;
if (shift == null || shift.Operator != Operator.Shr)
{
return(a);
}
var block = sidOrigLo.DefStatement.Block;
var sidShift = sidOrigHi.DefStatement;
var expShrSrc = shift.Left;
var expRorSrc = rorc.Arguments[0];
var stmGrf = sidGrf.DefStatement;
block.Statements.Remove(stmGrf);
var tmpHi = ssa.Procedure.Frame.CreateTemporary(expShrSrc.DataType);
var sidTmpHi = ssaIds.Add(tmpHi, sidOrigHi.DefStatement, expShrSrc, false);
sidOrigHi.DefStatement.Instruction = new Assignment(sidTmpHi.Identifier, expShrSrc);
var tmpLo = ssa.Procedure.Frame.CreateTemporary(rorc.Arguments[0].DataType);
var sidTmpLo = ssaIds.Add(tmpLo, sidOrigLo.DefStatement, rorc.Arguments[0], false);
sidOrigLo.DefStatement.Instruction = new Assignment(sidTmpLo.Identifier, rorc.Arguments[0]);
var iRorc = block.Statements.IndexOf(sidOrigLo.DefStatement);
var dt = PrimitiveType.Create(Domain.UnsignedInt, expShrSrc.DataType.Size + expRorSrc.DataType.Size);
var tmp = ssa.Procedure.Frame.CreateTemporary(dt);
var expMkLongword = m.Shr(m.Seq(sidTmpHi.Identifier, sidTmpLo.Identifier), 1);
var sidTmp = ssaIds.Add(tmp, sidGrf.DefStatement, expMkLongword, false);
var stmTmp = block.Statements.Insert(iRorc + 1, sidOrigLo.DefStatement.LinearAddress,
new Assignment(sidTmp.Identifier, expMkLongword));
sidTmp.DefStatement = stmTmp;
sidTmpHi.Uses.Add(stmTmp);
sidTmpLo.Uses.Add(stmTmp);
ssa.RemoveUses(sidCarry.DefStatement);
block.Statements.Remove(sidCarry.DefStatement);
ssaIds.Remove(sidCarry);
var expNewHi = m.Slice(
PrimitiveType.CreateWord(tmpHi.DataType.Size),
sidTmp.Identifier,
(uint)tmpLo.DataType.BitSize);
var stmNewHi = block.Statements.Insert(
iRorc + 2,
sidOrigHi.DefStatement.LinearAddress,
new Assignment(sidOrigHi.Identifier, expNewHi));
sidTmp.Uses.Add(stmNewHi);
sidOrigHi.DefStatement = stmNewHi;
sidOrigHi.DefExpression = expNewHi;
var expNewLo = m.Cast(
PrimitiveType.CreateWord(tmpLo.DataType.Size),
sidTmp.Identifier);
var stmNewLo = block.Statements.Insert(
iRorc + 3,
sidOrigLo.DefStatement.LinearAddress,
new Assignment(sidOrigLo.Identifier, expNewLo));
sidTmp.Uses.Add(stmNewLo);
sidOrigLo.DefStatement = stmNewLo;
sidOrigLo.DefStatement = stmNewLo;
sidGrf.DefExpression = m.Cond(sidTmp.Identifier);
sidGrf.DefStatement.Instruction = new Assignment(
sidGrf.Identifier, sidGrf.DefExpression);
sidTmp.Uses.Add(sidGrf.DefStatement);
ssa.DebugDump(true);
Debug.Print("sidGrf: *** {0}", sidGrf);
return(sidOrigLo.DefStatement.Instruction);
}