This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH] Fix PR56365
- From: Bernhard Reutner-Fischer <rep dot dot dot nop at gmail dot com>
- To: Richard Biener <rguenther at suse dot de>,gcc-patches at gcc dot gnu dot org
- Date: Mon, 14 Mar 2016 19:25:31 +0100
- Subject: Re: [PATCH] Fix PR56365
- Authentication-results: sourceware.org; auth=none
- References: <alpine dot LSU dot 2 dot 11 dot 1603141256400 dot 31547 at t29 dot fhfr dot qr>
On March 14, 2016 12:58:20 PM GMT+01:00, Richard Biener <rguenther@suse.de> wrote:
>
>I am testing the following patch to fix the regression in min/max
>detection introduced by comparison canonicalization like a < 267
>to a <= 266. The patch allows us to identify all four min/max
>cases in the testcase below.
>
>Bootstrap and regtest running on x86_64-unknown-linux-gnu.
>InLikew/testsuite/gcc.dg/tree-ssa/phi-opt-14.c
>===================================================================
>*** gcc/testsuite/gcc.dg/tree-ssa/phi-opt-14.c (revision 0)
>--- gcc/testsuite/gcc.dg/tree-ssa/phi-opt-14.c (working copy)
>***************
>*** 0 ****
>--- 1,37 ----
>+ /* { dg-do compile } */
>+ /* { dg-options "-O -fdump-tree-phiopt1" } */
>+
>+ int test_01 (int a)
>+ {
>+ if (127 <= a)
Shouldn't this be >= ?
>+ a = 127;
>+ else if (a <= -128)
>+ a = -128;
>+ return a;
>+ }
>+ int test_02 (int a)
>+ {
>+ if (127 < a)
and this >
>+ a = 127;
>+ else if (a <= -128)
>+ a = -128;
>+ return a;
>+ }
>+ int test_03 (int a)
>+ {
>+ if (127 <= a)
and this >=
>+ a = 127;
>+ else if (a < -128)
>+ a = -128;
>+ return a;
>+ }
>+ int test_04 (int a)
>+ {
>+ if (127 < a)
and >
TIA,
>+ a = 127;
>+ else if (a < -128)
>+ a = -128;
>+ return a;
>+ }
>+
>+ /* { dg-final { scan-tree-dump-not "if" "phiopt1" } } */