On Fri, May 9, 2025 at 4:51 AM Andrew Pinski <quic_apin...@quicinc.com> wrote:
>
> These patterns are not needed any more. There were already
> 2 patterns which did `(ne bool_var 0)` into `bool_var` and
> `(eq bool_var 1)` into `bool_var`. Just they were after the
> pattern that did `(cmp (cond @0 @1 @2) @3)` simplification but
> that pattern is now after the ones.
> Also these patterns will cause in some cases a new statement to
> be created for the comparison. In the case of floating point comparison
> wiht non-call exceptions (and trapping math), can cause a new statement
> every time fold_stmt is called.
Hmm, but do we still fold
_1 = _2 < 1;
if (_1 != 0)
to
if (_2 < 1)
or does that now again rely on forwprops explicit forwarding into
gcond? I wanted
to get rid of the latter eventually.
I agree that the trapping math thing is bad - I wonder if we can catch that more
intelligently (not sure how without following SSA use-def of gconds on bools
and see whether they can trap and then not simplifying)
> gcc.dg/tree-ssa/vrp24.c needed to be adjusted to before
> r13-322-g7f04b0d786e13f.
> gcc.dg/analyzer/null-deref-pr102671-2.c needs an increased
> analyzer-max-svalue-depth
> not to get an extra warning.
>
> gcc/ChangeLog:
>
> * match.pd (`(ne (cmp) 0)`, `(eq (cmp) 1)`): Remove.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/tree-ssa/vrp24.c: Adjust.
> * gcc.dg/analyzer/null-deref-pr102671-2.c: Increase
> analyzer-max-svalue-depth.
>
> Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
> ---
> gcc/match.pd | 8 --------
> gcc/testsuite/gcc.dg/analyzer/null-deref-pr102671-2.c | 2 +-
> gcc/testsuite/gcc.dg/tree-ssa/vrp24.c | 2 +-
> 3 files changed, 2 insertions(+), 10 deletions(-)
>
> diff --git a/gcc/match.pd b/gcc/match.pd
> index ab496d923cc..418efc4230a 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -6898,14 +6898,6 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> (if (ic == ncmp)
> (ncmp @0 @1)))))
> /* The following bits are handled by fold_binary_op_with_conditional_arg.
> */
> - (simplify
> - (ne (cmp@2 @0 @1) integer_zerop)
> - (if (types_match (type, TREE_TYPE (@2)))
> - (cmp @0 @1)))
> - (simplify
> - (eq (cmp@2 @0 @1) integer_truep)
> - (if (types_match (type, TREE_TYPE (@2)))
> - (cmp @0 @1)))
> (simplify
> (ne (cmp@2 @0 @1) integer_truep)
> (if (types_match (type, TREE_TYPE (@2)))
> diff --git a/gcc/testsuite/gcc.dg/analyzer/null-deref-pr102671-2.c
> b/gcc/testsuite/gcc.dg/analyzer/null-deref-pr102671-2.c
> index 298e4839b98..bc141d5c028 100644
> --- a/gcc/testsuite/gcc.dg/analyzer/null-deref-pr102671-2.c
> +++ b/gcc/testsuite/gcc.dg/analyzer/null-deref-pr102671-2.c
> @@ -1,5 +1,5 @@
> /* { dg-require-effective-target ptr_eq_long } */
> -/* { dg-additional-options "-O2 -Wno-shift-count-overflow" } */
> +/* { dg-additional-options "-O2 -Wno-shift-count-overflow
> --param=analyzer-max-svalue-depth=19" } */
>
> struct lisp;
> union vectorlike_header { long size; };
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/vrp24.c
> b/gcc/testsuite/gcc.dg/tree-ssa/vrp24.c
> index c28ca473fc6..f237b7741ec 100644
> --- a/gcc/testsuite/gcc.dg/tree-ssa/vrp24.c
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/vrp24.c
> @@ -89,5 +89,5 @@ L7:
> boolean operation. */
>
> /* { dg-final { scan-tree-dump-times "Simplified relational" 2 "evrp" } } */
> -/* { dg-final { scan-tree-dump-times "if " 3 "optimized" } } */
> +/* { dg-final { scan-tree-dump-times "if " 4 "optimized" } } */
>
> --
> 2.43.0
>
