int SUB_STMT(){//SUB_STMT() | SUB_STATEMENT -> id=E; SUB_STATEMENT | STATEMENT_LIST SUB_STATEMENT | e
if(getNextToken()==ID){
printf(" assignment begins\n");
sa_index++;
if(getNextToken()==ASSIGN){
sa_index++;
if(E()==TRUE){
if(getNextToken()==SEMICOLON){
sa_index++;
printf(" assignment ends\n");
if(SUB_STMT()==TRUE){
return TRUE;
}
return FALSE;
}
return FALSE;
}
return FALSE;
}
return FALSE;
}
if(STMT_LIST()==TRUE){
if(SUB_STMT()==TRUE){
return TRUE;
}
return FALSE;
}
return TRUE;
}
int PROG_BODY(){
printf(" Program body begins\n");
if(getNextToken()==VAR){
printf(" declaration begins\n");
sa_index++;
if(ID_LIST()==TRUE){
if(getNextToken()==SEMICOLON){
printf(" declaration ends\n");
sa_index++;
if(STMT_LIST()==TRUE){
printf(" Program body ends\n");
return TRUE;
}
return FALSE;
}
return FALSE;
}
return FALSE;
}
return FALSE;
}
int c_codegen_recurse(c_tree tree, int *registerNo, int topLevel,
int getAddress, const char *breakLabel, const char *continueLabel)
{
if (tree == NULL)
return *registerNo;
switch (TREE_CODE(tree))
{
case TREE_INTEGER_CST :
if (!topLevel)
{
SET(*registerNo, INTEGER_CST(tree)->val, "integer constant", "");
return (*registerNo)++;
}
break;
case TREE_IDENTIFIER :
break;
case TREE_CHAIN :
while (tree)
{
c_codegen_recurse(CHAIN_VALUE(tree), registerNo, topLevel,
getAddress, breakLabel, continueLabel);
tree = CHAIN_NEXT(tree);
}
break;
case TREE_EXPR :
return exprCodeGen(tree, registerNo, topLevel, getAddress,
breakLabel, continueLabel);
break;
case TREE_EXPR_LIST :
if (EXPR_LIST(tree)->chain)
c_codegen_recurse(EXPR_LIST(tree)->chain, registerNo, TRUE,
getAddress, breakLabel, continueLabel);
break;
case TREE_WHILE :
return whileCodeGen(tree, registerNo, topLevel, getAddress,
breakLabel, continueLabel);
break;
case TREE_FOR :
return forCodeGen(tree, registerNo, topLevel, getAddress,
breakLabel, continueLabel);
break;
case TREE_IFELSE :
return ifCodeGen(tree, registerNo, topLevel, getAddress,
breakLabel, continueLabel);
break;
case TREE_EXPRSTMT :
c_codegen_recurse(EXPR_STMT(tree)->expr, registerNo, topLevel,
getAddress, breakLabel, continueLabel);
break;
case TREE_COMPOUND :
if (COMPOUND_STMT(tree)->decllist)
c_codegen_recurse(COMPOUND_STMT(tree)->decllist, registerNo,
topLevel, getAddress, breakLabel, continueLabel);
if (COMPOUND_STMT(tree)->stmtlist)
c_codegen_recurse(COMPOUND_STMT(tree)->stmtlist, registerNo,
topLevel, getAddress, breakLabel, continueLabel);
break;
case TREE_RETURN :
return returnCodegen(tree, registerNo, getAddress, breakLabel,
continueLabel);
break;
case TREE_DECL :
return declCodeGen(tree, registerNo, topLevel, getAddress,
breakLabel, continueLabel);
break;
// }
break;
case TREE_STMT_LIST :
if (STMT_LIST(tree)->head)
{
c_codegen_recurse(STMT_LIST(tree)->head, registerNo, topLevel,
getAddress, breakLabel, continueLabel);
}
break;
case TREE_BREAK :
breakCodeGen(breakLabel);
break;
case TREE_CONTINUE :
continueCodeGen(continueLabel);
break;
default :
break;
}
return *registerNo;
}
