/// <summary>
/// Inserts the assignment <paramref name="ass"/> before the statement
/// <paramref name="stm"/> if it is in the same block. Otherwise append
/// it to the end of the statements in the block.
/// </summary>
public SsaIdentifier InsertBeforeStatement(Block block, Statement stm, Assignment ass)
{
Statement stmNew;
if (stm.Block == block)
{
int i = stm.Block.Statements.IndexOf(stm);
stmNew = new Statement(stm.LinearAddress, ass, stm.Block);
stm.Block.Statements.Insert(i, stmNew);
}
else
{
ulong uAddr = block.Address.ToLinear();
int i = -1;
if (block.Statements.Count > 0)
{
i = block.Statements.Count - 1;
if (block.Statements[i].Instruction.IsControlFlow)
{
--i;
}
if (i >= 0)
{
uAddr = block.Statements[i].LinearAddress;
}
}
stmNew = block.Statements.Insert(i + 1, uAddr, ass);
}
var sidTo = ssaIds.Add(ass.Dst, stmNew, ass.Src, false);
ass.Dst = sidTo.Identifier;
return(sidTo);
}
private Instruction TransformRolC(Application rolc, Assignment a)
{
var sidOrigHi = ssaIds[a.Dst];
var sidCarry = ssaIds[(Identifier)rolc.Arguments[2]];
if (!(sidCarry.DefExpression is ConditionOf cond))
{
return(a);
}
if (!(cond.Expression is Identifier condId))
{
return(a);
}
var sidOrigLo = ssaIds[condId];
if (!(sidOrigLo.DefExpression is BinaryExpression shift) || shift.Operator != Operator.Shl)
{
return(a);
}
var block = sidOrigHi.DefStatement !.Block;
var expShrSrc = shift.Left;
var expRorSrc = rolc.Arguments[0];
var stmGrf = sidGrf !.DefStatement;
block.Statements.Remove(stmGrf !);
// xx = lo
var tmpLo = ssa.Procedure.Frame.CreateTemporary(expShrSrc.DataType);
var sidTmpLo = ssaIds.Add(tmpLo, sidOrigLo.DefStatement, expShrSrc, false);
sidOrigLo.DefStatement !.Instruction = new Assignment(sidTmpLo.Identifier, expShrSrc);
var tmpHi = ssa.Procedure.Frame.CreateTemporary(rolc.Arguments[0].DataType);
var sidTmpHi = ssaIds.Add(tmpHi, sidOrigHi.DefStatement, rolc.Arguments[0], false);
sidOrigHi.DefStatement.Instruction = new Assignment(sidTmpHi.Identifier, rolc.Arguments[0]);
var iRolc = block.Statements.IndexOf(sidOrigHi.DefStatement);
var dt = PrimitiveType.Create(Domain.Integer, expShrSrc.DataType.BitSize + expRorSrc.DataType.BitSize);
var tmp = ssa.Procedure.Frame.CreateTemporary(dt);
var expMkLongword = m.Shl(m.Seq(sidTmpHi.Identifier, sidTmpLo.Identifier), 1);
var sidTmp = ssaIds.Add(tmp, sidGrf.DefStatement, expMkLongword, false);
var stmTmp = block.Statements.Insert(iRolc + 1, sidOrigHi.DefStatement.LinearAddress,
new Assignment(sidTmp.Identifier, expMkLongword));
sidTmp.DefStatement = stmTmp;
sidTmpLo.Uses.Add(stmTmp);
sidTmpHi.Uses.Add(stmTmp);
ssa.RemoveUses(sidCarry.DefStatement !);
block.Statements.Remove(sidCarry.DefStatement !);
ssaIds.Remove(sidCarry);
var expNewLo = m.Cast(
PrimitiveType.CreateWord(tmpHi.DataType.BitSize),
sidTmp.Identifier);
var stmNewLo = block.Statements.Insert(
iRolc + 2,
sidOrigLo.DefStatement.LinearAddress,
new Assignment(sidOrigLo.Identifier, expNewLo));
sidTmp.Uses.Add(stmNewLo);
sidOrigLo.DefStatement = stmNewLo;
sidOrigLo.DefExpression = expNewLo;
var expNewHi = m.Slice(
PrimitiveType.CreateWord(tmpLo.DataType.BitSize),
sidTmp.Identifier,
tmpHi.DataType.BitSize);
var stmNewHi = block.Statements.Insert(
iRolc + 3,
sidOrigHi.DefStatement.LinearAddress,
new Assignment(sidOrigHi.Identifier, expNewHi));
sidTmp.Uses.Add(stmNewHi);
sidOrigHi.DefStatement = stmNewHi;
sidOrigHi.DefStatement = stmNewHi;
sidGrf.DefExpression = null;
sidGrf.DefStatement = null;
return(sidOrigHi.DefStatement.Instruction);
}