On Tue, 3 Sep 2013 10:38:33, Richard Biener wrote: > I'd rather go with the simple fix as the issue in forwprop is at least > latent. We can > improve on the code-gen as followup where I believe handling of > POINTER_PLUS_EXPR > would need to be added (that we avoid POINTER_PLUS_EXPR for vectors is a bug). > That can be done in a way to cover the vector case properly. Or > finally properly > use POINTER_PLUS_EXPR for vectors or make the vectorizer not use pointer > types but a corresponding unsigned integer type for them (that would also fix > the original bug of course). Like with (untested) > > Index: gcc/tree-vect-stmts.c > =================================================================== > --- gcc/tree-vect-stmts.c (revision 202196) > +++ gcc/tree-vect-stmts.c (working copy) > @@ -6179,8 +6179,7 @@ get_vectype_for_scalar_type_and_size (tr > corresponding to that mode. The theory is that any use that > would cause problems with this will disable vectorization anyway. */ > else if (!SCALAR_FLOAT_TYPE_P (scalar_type) > - && !INTEGRAL_TYPE_P (scalar_type) > - && !POINTER_TYPE_P (scalar_type)) > + && !INTEGRAL_TYPE_P (scalar_type)) > scalar_type = lang_hooks.types.type_for_mode (inner_mode, 1); > > /* We can't build a vector type of elements with alignment bigger than > > actually that would be my preference here ...
this would cause an ICE in test case 20000629-1.c... So removing the pointer of vectors is not an option. >>> The real fix is of course to make vector pointer operations properly >>> use POINTER_PLUS_EXPR ... Okay I can do what you want, and use POINTER_PLUS_EXPR for vectors of pointers, and do the constant folding in assocate_pointerplus. This way we get exactly the same code as before. It may be even possible that this constant folding can improve something with scalars. Bootstrapped and regression tested on x86_64-unknown-linux-gnu. OK for trunk? Bernd.
2013-09-05 Bernd Edlinger <bernd.edlin...@hotmail.de>
PR tree-optimization/58137
Use POINTER_PLUS_EXPR for vector of pointer additions.
* tree-cfg.c (verify_gimple_assign_binary)
<PLUS_EXPR, MINUS_EXPR>: Remove vector of pointer handling.
<POINTER_PLUS_EXPR>: Add vector of pointer type check.
* tree.c (build2_stat) <POINTER_PLUS_EXPR>: Allow vector of pointer.
* tree-vect-stmts.c (vectorizable_operation): Do not replace
POINTER_PLUS_EXPR with PLUS_EXPR.
* tree-vect-loop.c (get_initial_def_for_induction): Use
POINTER_PLUS_EXPR for vector of pointer.
testsuite:
* gcc.target/i386/pr58137.c: New test.
patch-forwprop.diff
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