public inbox for gcc-cvs@sourceware.org help / color / mirror / Atom feed
From: Sam Feifer <sfeifer@gcc.gnu.org> To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-1785] match.pd: Add new abs pattern [PR94920] Date: Thu, 21 Jul 2022 21:27:38 +0000 (GMT) [thread overview] Message-ID: <20220721212738.6435D3835839@sourceware.org> (raw) https://gcc.gnu.org/g:633e9920589ddfaf2d6da1c24ce99b18a2638db4 commit r13-1785-g633e9920589ddfaf2d6da1c24ce99b18a2638db4 Author: Sam Feifer <sfeifer@redhat.com> Date: Thu Jul 21 16:31:41 2022 -0400 match.pd: Add new abs pattern [PR94920] This patch is intended to fix a missed optimization in match.pd. It optimizes (x >= 0 ? x : 0) + (x <= 0 ? -x : 0) to just abs(x). Additionally, the pattern (x <= 0 ? -x : 0) now gets optimized to max(-x, 0), which helps with the other simplification rule. Tests are also included to be added to the testsuite. Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? PR tree-optimization/94920 gcc/ChangeLog: * match.pd (x >= 0 ? x : 0) + (x <= 0 ? -x : 0): New simplification. (x <= 0 ? -x : 0): New simplification. gcc/testsuite/ChangeLog: * g++.dg/pr94920-1.C: New test. * g++.dg/pr94920.C: New test. * gcc.dg/pr94920-2.c: New test. Diff: --- gcc/match.pd | 10 +++++++ gcc/testsuite/g++.dg/pr94920-1.C | 17 +++++++++++ gcc/testsuite/g++.dg/pr94920.C | 63 ++++++++++++++++++++++++++++++++++++++++ gcc/testsuite/gcc.dg/pr94920-2.c | 15 ++++++++++ 4 files changed, 105 insertions(+) diff --git a/gcc/match.pd b/gcc/match.pd index 88a1a5aa9cc..9736393061a 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -339,6 +339,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@0))) (COPYSIGN_ALL (negate @0) @1))) +/* (x >= 0 ? x : 0) + (x <= 0 ? -x : 0) -> abs x. */ +(simplify + (plus:c (max @0 integer_zerop) (max (negate @0) integer_zerop)) + (abs @0)) + /* X * 1, X / 1 -> X. */ (for op (mult trunc_div ceil_div floor_div round_div exact_div) (simplify @@ -3425,6 +3430,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) && (GIMPLE || !TREE_SIDE_EFFECTS (@1))) (cond (convert:boolean_type_node @2) @1 @0))) +/* (x <= 0 ? -x : 0) -> max(-x, 0). */ +(simplify + (cond (le @0 integer_zerop@1) (negate@2 @0) integer_zerop@1) + (max @2 @1)) + /* Simplifications of shift and rotates. */ (for rotate (lrotate rrotate) diff --git a/gcc/testsuite/g++.dg/pr94920-1.C b/gcc/testsuite/g++.dg/pr94920-1.C new file mode 100644 index 00000000000..6c6483eab2d --- /dev/null +++ b/gcc/testsuite/g++.dg/pr94920-1.C @@ -0,0 +1,17 @@ +/* PR tree-optimization/94920 */ +/* { dg-do run } */ + +#include "pr94920.C" + +int main() { + + if (foo(0) != 0 + || foo(-42) != 42 + || foo(42) != 42 + || baz(-10) != 10 + || baz(-10) != 10) { + __builtin_abort(); + } + + return 0; +} diff --git a/gcc/testsuite/g++.dg/pr94920.C b/gcc/testsuite/g++.dg/pr94920.C new file mode 100644 index 00000000000..925ec4f42f1 --- /dev/null +++ b/gcc/testsuite/g++.dg/pr94920.C @@ -0,0 +1,63 @@ +/* PR tree-optimization/94920 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ + +typedef int __attribute__((vector_size(4*sizeof(int)))) vint; + +/* Same form as PR. */ +__attribute__((noipa)) unsigned int foo(int x) { + return (x >= 0 ? x : 0) + (x <= 0 ? -x : 0); +} + +/* Test for forward propogation. */ +__attribute__((noipa)) unsigned int corge(int x) { + int w = (x >= 0 ? x : 0); + int y = -x; + int z = (y >= 0 ? y : 0); + return w + z; +} + +/* Vector case. */ +__attribute__((noipa)) vint thud(vint x) { + vint t = (x >= 0 ? x : 0) ; + vint xx = -x; + vint t1 = (xx >= 0 ? xx : 0); + return t + t1; +} + +/* Signed function. */ +__attribute__((noipa)) int bar(int x) { + return (x >= 0 ? x : 0) + (x <= 0 ? -x : 0); +} + +/* Commutative property. */ +__attribute__((noipa)) unsigned int baz(int x) { + return (x <= 0 ? -x : 0) + (x >= 0 ? x : 0); +} + +/* Flipped order for max expressions. */ +__attribute__((noipa)) unsigned int quux(int x) { + return (0 <= x ? x : 0) + (0 >= x ? -x : 0); +} + +/* Not zero so should not optimize. */ +__attribute__((noipa)) unsigned int waldo(int x) { + return (x >= 4 ? x : 4) + (x <= 4 ? -x : 4); +} + +/* Not zero so should not optimize. */ +__attribute__((noipa)) unsigned int fred(int x) { + return (x >= -4 ? x : -4) + (x <= -4 ? -x : -4); +} + +/* Incorrect pattern. */ +__attribute__((noipa)) unsigned int goo(int x) { + return (x <= 0 ? x : 0) + (x >= 0 ? -x : 0); +} + +/* Incorrect pattern. */ +__attribute__((noipa)) int qux(int x) { + return (x >= 0 ? x : 0) + (x >= 0 ? x : 0); +} + +/* { dg-final {scan-tree-dump-times " ABS_EXPR " 6 "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/pr94920-2.c b/gcc/testsuite/gcc.dg/pr94920-2.c new file mode 100644 index 00000000000..a2d23324cfa --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr94920-2.c @@ -0,0 +1,15 @@ +/* PR tree-optimization/94920 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ + +/* Form from PR. */ +__attribute__((noipa)) unsigned int foo(int x) { + return x <= 0 ? -x : 0; +} + +/* Changed order. */ +__attribute__((noipa)) unsigned int bar(int x) { + return 0 >= x ? -x : 0; +} + +/* { dg-final {scan-tree-dump-times " MAX_EXPR " 2 "optimized" } } */
reply other threads:[~2022-07-21 21:27 UTC|newest] Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20220721212738.6435D3835839@sourceware.org \ --to=sfeifer@gcc.gnu.org \ --cc=gcc-cvs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).