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* [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result @ 2021-08-18 10:52 channhuang at 163 dot com 2021-08-18 11:42 ` [Bug rtl-optimization/101958] " marxin at gcc dot gnu.org ` (6 more replies) 0 siblings, 7 replies; 8+ messages in thread From: channhuang at 163 dot com @ 2021-08-18 10:52 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101958 Bug ID: 101958 Summary: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result Product: gcc Version: 11.2.0 Status: UNCONFIRMED Keywords: missed-optimization, wrong-code Severity: normal Priority: P3 Component: rtl-optimization Assignee: unassigned at gcc dot gnu.org Reporter: channhuang at 163 dot com CC: jakub at gcc dot gnu.org Target Milestone: --- Host: x86_64-pc-linux-gnu Target: x86_64-pc-linux-gnu Build: x86_64-pc-linux-gnu gcc-11.2.0, x86_64-pc-linux-gnu, compiling with the following options: "-O2 -fselective-scheduling2 -fno-tree-ch -lm" The source code is for counting the number of primes up to 10000. #include <stdio.h> #include <math.h> unsigned long max_prime =10000; int cpu_execute_event() { unsigned long c,l; int n = 0; double t; for(c = 2; c < max_prime; c++) { t = sqrt((double)c); for(l = 2; l <= t; l++) if (c % l == 0) break; if (l > t ) n++; } return n; } int main () { int n; n = cpu_execute_event(); printf("n:%d\n",n); return 0; } The real return value of cpu_execute_event() is 2 where it should be 1229. It works correctly when I compiled with "-O2 -fselective-scheduling2" or "-O2 -fno-tree-ch".I suspect that instruction scheduling changes the meaning of the code.And gcc10.2 also produces the same phenomenon. The command line is the following: gcc-11.2 cpu_execute_event.c -O2 -fselective-scheduling2 -fno-tree-ch -lm There is no output message, no error, no warning even compiled with the options "-Wall -Wextra". I use gcc 11.2.0, configured with: ../gcc-11.2.0/configure --prefix=/home/chann/gcc/gcc11_2 --enable-threads=posix --disable-checking --disable-multilib --enable-languages=c,c++ ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug rtl-optimization/101958] compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result 2021-08-18 10:52 [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result channhuang at 163 dot com @ 2021-08-18 11:42 ` marxin at gcc dot gnu.org 2021-08-18 11:44 ` [Bug rtl-optimization/101958] [9/10/11/12 Regression] " jakub at gcc dot gnu.org ` (5 subsequent siblings) 6 siblings, 0 replies; 8+ messages in thread From: marxin at gcc dot gnu.org @ 2021-08-18 11:42 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101958 Martin Liška <marxin at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |marxin at gcc dot gnu.org Status|UNCONFIRMED |NEW Ever confirmed|0 |1 Last reconfirmed| |2021-08-18 --- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> --- Confirmed, started with r9-6789-g8bad0ced9fad845e. ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug rtl-optimization/101958] [9/10/11/12 Regression] compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result 2021-08-18 10:52 [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result channhuang at 163 dot com 2021-08-18 11:42 ` [Bug rtl-optimization/101958] " marxin at gcc dot gnu.org @ 2021-08-18 11:44 ` jakub at gcc dot gnu.org 2022-01-17 13:54 ` rguenth at gcc dot gnu.org ` (4 subsequent siblings) 6 siblings, 0 replies; 8+ messages in thread From: jakub at gcc dot gnu.org @ 2021-08-18 11:44 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101958 Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|--- |9.5 Summary|compiling with "-O2 |[9/10/11/12 Regression] |-fselective-scheduling2 |compiling with "-O2 |-fno-tree-ch" produce bad |-fselective-scheduling2 |result |-fno-tree-ch" produce bad | |result --- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Then it is a regression. ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug rtl-optimization/101958] [9/10/11/12 Regression] compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result 2021-08-18 10:52 [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result channhuang at 163 dot com 2021-08-18 11:42 ` [Bug rtl-optimization/101958] " marxin at gcc dot gnu.org 2021-08-18 11:44 ` [Bug rtl-optimization/101958] [9/10/11/12 Regression] " jakub at gcc dot gnu.org @ 2022-01-17 13:54 ` rguenth at gcc dot gnu.org 2022-05-27 9:46 ` [Bug rtl-optimization/101958] [10/11/12/13 " rguenth at gcc dot gnu.org ` (3 subsequent siblings) 6 siblings, 0 replies; 8+ messages in thread From: rguenth at gcc dot gnu.org @ 2022-01-17 13:54 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101958 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Priority|P3 |P2 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug rtl-optimization/101958] [10/11/12/13 Regression] compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result 2021-08-18 10:52 [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result channhuang at 163 dot com ` (2 preceding siblings ...) 2022-01-17 13:54 ` rguenth at gcc dot gnu.org @ 2022-05-27 9:46 ` rguenth at gcc dot gnu.org 2022-06-28 10:46 ` jakub at gcc dot gnu.org ` (2 subsequent siblings) 6 siblings, 0 replies; 8+ messages in thread From: rguenth at gcc dot gnu.org @ 2022-05-27 9:46 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101958 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|9.5 |10.4 --- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> --- GCC 9 branch is being closed ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug rtl-optimization/101958] [10/11/12/13 Regression] compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result 2021-08-18 10:52 [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result channhuang at 163 dot com ` (3 preceding siblings ...) 2022-05-27 9:46 ` [Bug rtl-optimization/101958] [10/11/12/13 " rguenth at gcc dot gnu.org @ 2022-06-28 10:46 ` jakub at gcc dot gnu.org 2023-07-07 10:40 ` [Bug rtl-optimization/101958] [11/12/13/14 " rguenth at gcc dot gnu.org 2024-03-11 3:47 ` law at gcc dot gnu.org 6 siblings, 0 replies; 8+ messages in thread From: jakub at gcc dot gnu.org @ 2022-06-28 10:46 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101958 Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|10.4 |10.5 --- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> --- GCC 10.4 is being released, retargeting bugs to GCC 10.5. ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug rtl-optimization/101958] [11/12/13/14 Regression] compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result 2021-08-18 10:52 [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result channhuang at 163 dot com ` (4 preceding siblings ...) 2022-06-28 10:46 ` jakub at gcc dot gnu.org @ 2023-07-07 10:40 ` rguenth at gcc dot gnu.org 2024-03-11 3:47 ` law at gcc dot gnu.org 6 siblings, 0 replies; 8+ messages in thread From: rguenth at gcc dot gnu.org @ 2023-07-07 10:40 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101958 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|10.5 |11.5 --- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> --- GCC 10 branch is being closed. ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug rtl-optimization/101958] [11/12/13/14 Regression] compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result 2021-08-18 10:52 [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result channhuang at 163 dot com ` (5 preceding siblings ...) 2023-07-07 10:40 ` [Bug rtl-optimization/101958] [11/12/13/14 " rguenth at gcc dot gnu.org @ 2024-03-11 3:47 ` law at gcc dot gnu.org 6 siblings, 0 replies; 8+ messages in thread From: law at gcc dot gnu.org @ 2024-03-11 3:47 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101958 Jeffrey A. Law <law at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |law at gcc dot gnu.org Priority|P2 |P4 ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2024-03-11 3:47 UTC | newest] Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-08-18 10:52 [Bug rtl-optimization/101958] New: compiling with "-O2 -fselective-scheduling2 -fno-tree-ch" produce bad result channhuang at 163 dot com 2021-08-18 11:42 ` [Bug rtl-optimization/101958] " marxin at gcc dot gnu.org 2021-08-18 11:44 ` [Bug rtl-optimization/101958] [9/10/11/12 Regression] " jakub at gcc dot gnu.org 2022-01-17 13:54 ` rguenth at gcc dot gnu.org 2022-05-27 9:46 ` [Bug rtl-optimization/101958] [10/11/12/13 " rguenth at gcc dot gnu.org 2022-06-28 10:46 ` jakub at gcc dot gnu.org 2023-07-07 10:40 ` [Bug rtl-optimization/101958] [11/12/13/14 " rguenth at gcc dot gnu.org 2024-03-11 3:47 ` law at gcc dot gnu.org
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