On Thu, Jun 26, 2014 at 10:11 AM, Prathamesh Kulkarni
<bilbotheelffri...@gmail.com> wrote:
> This patch factors expression checking for GIMPLE.
>
> Generates code as:
> if (TREE_CODE (opname) == SSA_NAME)
> {
> gimple def_stmt = SSA_NAME_DEF_STMT (opname);
> if (is_gimple_assign (def_stmt))
> {
> if (gimple_assign_rhs_code (def_stmt) == <expr-code1>)
> {
> ....
> }
> if (gimple_assign_rhs_code (def_stmt) == <expr-code2>)
> {
> ....
> }
> }
> }
>
> We cannot use switch-case, for convert/nop since
> we use CONVERT_EXPR_CODE_P, so i used if stmt.
Actually we can by using
case NOP_EXPR:
case CONVERT_EXPR:
for it. Note that currently you still do
if (is_gimple_assign (def_stmt))
{
if (gimple_assign_rhs_code (def_stmt) == PLUS_EXPR)
{
}
if (gimple_assign_rhs_code (def_stmt) == MINUS_EXPR)
{
}
thus not use else if (). Of course in the end we want
switch (gimple_assign_rhs_code (def_stmt))
{
case PLUS_EXPR;
...
case MINUS_EXPR:
...
> Unfortunately, back-tracking is still done. I shall look into that.
Note that we need to backtrack to the next parent with a 'true'
kid (and from there to its next parent with a 'true' kid). Possibly
with using a switch-case or proper if-else-if there isn't anything
special to do as the backtracking would work naturally then.
So I suggest to concentrate on getting the code to use
if (TREE_CODE (op0) == SSA_NAME)
{
gimple def_stmt = SSA_NAME_DEF_STMT (op0);
if (is_gimple_assign (def_stmt))
{
switch (gimple_assign_rhs_code ())
{
case PLUS_EXPR:
...
}
else if (gimple_call_builtin_p (def_stmt, BUILT_IN_NORMAL))
{
switch (DECL_FUNCTION_CODE (gimple_call_fndecl (def_stmt)))
{
case BUILT_IN_ABS:
...
}
}
else if (TREE_CODE (op0) == REALPART_EXPR)
... other GENERIC cases
<true> match (not in else {})
that would backtrack through the <true> cases by means of them
not short-circuited by an else but everything else short-circuited
by proper use of switch () and if - else-if code.
Thanks,
Richard.
> * genmatch.c (dt_node::get_expr_code): New member function.
> (dt_node::is_gimple_expr): Likewise.
> (dt_node::is_gimple_fn): Likewise.
> (dt_operand::kids_type): New struct.
> (dt_operand::gen_gimple_expr): Remove.
> (dt_operand::gen_gimple_expr_expr): Remove 2nd argument and
> change return type to unsigned. Adjust code-gen for
> expressions.
> (dt_operand::gen_gimple_expr_fn): Remove 2nd argument and change
> return type to unsigned.
> (dt_operand::grok_kids): New member function.
> (dt_operand::gen_gimple_kids): Likewise.
> (dt_operand::gen_gimple): Adjust code-gen for gimple expressions.
> Call dt_operand::gen_gimple_kids.
> (decision_tree::gen_gimple): Call dt_operand::gen_gimple_kids.
>
> Thanks and Regards,
> Prathamesh
