On 10 June 2011 12:14, Richard Guenther <richard.guenther@gmail.com> wrote:
> In the end I think we should not generate the pattern stmt during
> pattern matching but only mark the relevant statements with a
> pattern kind.  Say, for each pattern we have a "main" statement
> that has related stmts belonging to the pattern that define uses
> of the "main" statement - mark those to refer to that "main" statement.
> For that "main" statement simply record an enum value, like,
> widening_mult.  Then only at vectorized statement
> generation time actually generate the vectorized form of the
> pattern statement.

I ended up with the following: during pattern detection a new scalar
pattern statement is created but not inserted into the code, it is
only recorded as a related statement of the last statement in the
detected pattern. Every time the last statement is being
analyzed/transformed, we switch to the pattern statement instead. It
is much more difficult just to mark the last stmt with an enum value,
since we have to retrieve the relevant operands every time.

I am not sure if we need to free the pattern stmt at the end.

Bootstrapped and now testing on powerpc64-suse-linux (tested
vectorizer testsuite on powerpc64-suse-linux and x86_64-suse-linux.

What do you think?

Thanks,
Ira

ChangeLog:

     * tree-vect-loop.c (vect_determine_vectorization_factor): Don't
     remove irrelevant pattern statements.  For irrelevant statements
     check if it is the last statement of a detected pattern, use
     corresponding pattern statement instead.
     (destroy_loop_vec_info): No need to remove pattern statements,
     only free stmt_vec_info.
     (vect_transform_loop): For irrelevant statements check if it is
     the last statement of a detected pattern, use corresponding
     pattern statement instead.
     * tree-vect-patterns.c (vect_pattern_recog_1): Don't insert
     pattern statements.  Set basic block for the new statement.
     (vect_pattern_recog): Update documentation.
     * tree-vect-stmts.c (vect_mark_stmts_to_be_vectorized): Scan
     operands of pattern statements.
     (vectorizable_call): Fix printing.  In case of a pattern statement
     use the lhs of the original statement when creating a dummy
     statement to replace the original call.
     (vect_analyze_stmt): For irrelevant statements check if it is
     the last statement of a detected pattern, use corresponding
     pattern statement instead.
     * tree-vect-slp.c (vect_schedule_slp_instance): For pattern
     statements use gsi of the original statement.