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* [Bug tree-optimization/98640] New: GCC produces incorrect code with -O1 and higher
@ 2021-01-12 17:01 vsevolod.livinskij at frtk dot ru
2021-01-12 18:45 ` [Bug tree-optimization/98640] [10/11 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 marxin at gcc dot gnu.org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: vsevolod.livinskij at frtk dot ru @ 2021-01-12 17:01 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98640
Bug ID: 98640
Summary: GCC produces incorrect code with -O1 and higher
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: vsevolod.livinskij at frtk dot ru
Target Milestone: ---
Reproducer:
#include <stdio.h>
unsigned long long int var_0 = 18128133247277979402ULL;
long long int var_14 = 6557021550272328915LL;
unsigned long long int var_83 = 10966786425750692026ULL;
void test() {
var_14 = var_0 + (bool)7;
var_83 = 1 + (int)var_0; // 1 + 888395530
}
int main() {
test();
printf("%llu\n", var_83);
}
https://godbolt.org/z/axYx1f
>$ g++ -O0 driver.cpp && ./a.out
888395531
>$ g++ -O1 driver.cpp && ./a.out
18128133247277979403
gcc version 11.0.0 20210112 (cf2ac1c30af0fa783c8d72e527904dda5d8cc330)
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug tree-optimization/98640] [10/11 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 2021-01-12 17:01 [Bug tree-optimization/98640] New: GCC produces incorrect code with -O1 and higher vsevolod.livinskij at frtk dot ru @ 2021-01-12 18:45 ` marxin at gcc dot gnu.org 2021-01-13 8:18 ` rguenth at gcc dot gnu.org ` (3 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: marxin at gcc dot gnu.org @ 2021-01-12 18:45 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98640 Martin Liška <marxin at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Ever confirmed|0 |1 Last reconfirmed| |2021-01-12 Summary|GCC produces incorrect code |[10/11 Regression] GCC |with -O1 and higher |produces incorrect code | |with -O1 and higher since | |r10-2711-g3ed01d5408045d80 Target Milestone|--- |10.3 CC| |marxin at gcc dot gnu.org, | |rguenth at gcc dot gnu.org Known to fail| |10.2.0, 11.0 --- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> --- Thanks for the report, started with r10-2711-g3ed01d5408045d80. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/98640] [10/11 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 2021-01-12 17:01 [Bug tree-optimization/98640] New: GCC produces incorrect code with -O1 and higher vsevolod.livinskij at frtk dot ru 2021-01-12 18:45 ` [Bug tree-optimization/98640] [10/11 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 marxin at gcc dot gnu.org @ 2021-01-13 8:18 ` rguenth at gcc dot gnu.org 2021-01-13 10:13 ` cvs-commit at gcc dot gnu.org ` (2 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: rguenth at gcc dot gnu.org @ 2021-01-13 8:18 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98640 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |ASSIGNED Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot gnu.org Priority|P3 |P2 --- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- I will have a look. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/98640] [10/11 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 2021-01-12 17:01 [Bug tree-optimization/98640] New: GCC produces incorrect code with -O1 and higher vsevolod.livinskij at frtk dot ru 2021-01-12 18:45 ` [Bug tree-optimization/98640] [10/11 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 marxin at gcc dot gnu.org 2021-01-13 8:18 ` rguenth at gcc dot gnu.org @ 2021-01-13 10:13 ` cvs-commit at gcc dot gnu.org 2021-03-03 10:36 ` [Bug tree-optimization/98640] [10 " cvs-commit at gcc dot gnu.org 2021-03-03 10:37 ` rguenth at gcc dot gnu.org 4 siblings, 0 replies; 6+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2021-01-13 10:13 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98640 --- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>: https://gcc.gnu.org/g:ffd28c265e6d611983cd27e9332dc799039a3f04 commit r11-6632-gffd28c265e6d611983cd27e9332dc799039a3f04 Author: Richard Biener <rguenther@suse.de> Date: Wed Jan 13 09:43:52 2021 +0100 tree-optimization/98640 - fix bogus sign-extension with VN VN tried to express a sign extension from int to long of a trucated quantity with a plain conversion but that loses the truncation. Since there's no single operand doing truncate plus sign extend (there was a proposed SEXT_EXPR to do that at some point mapping to RTL sign_extract) don't bother to appropriately model this with two ops (which the VN insert machinery doesn't handle and which is unlikely to CSE fully). 2021-01-13 Richard Biener <rguenther@suse.de> PR tree-optimization/98640 * tree-ssa-sccvn.c (visit_nary_op): Do not try to handle plus or minus from a truncated operand to be sign-extended. * gcc.dg/torture/pr98640.c: New testcase. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/98640] [10 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 2021-01-12 17:01 [Bug tree-optimization/98640] New: GCC produces incorrect code with -O1 and higher vsevolod.livinskij at frtk dot ru ` (2 preceding siblings ...) 2021-01-13 10:13 ` cvs-commit at gcc dot gnu.org @ 2021-03-03 10:36 ` cvs-commit at gcc dot gnu.org 2021-03-03 10:37 ` rguenth at gcc dot gnu.org 4 siblings, 0 replies; 6+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2021-03-03 10:36 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98640 --- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-10 branch has been updated by Richard Biener <rguenth@gcc.gnu.org>: https://gcc.gnu.org/g:268b54382e5248ee1a5e3f4a0841358e03290d17 commit r10-9407-g268b54382e5248ee1a5e3f4a0841358e03290d17 Author: Richard Biener <rguenther@suse.de> Date: Wed Jan 13 09:43:52 2021 +0100 tree-optimization/98640 - fix bogus sign-extension with VN VN tried to express a sign extension from int to long of a trucated quantity with a plain conversion but that loses the truncation. Since there's no single operand doing truncate plus sign extend (there was a proposed SEXT_EXPR to do that at some point mapping to RTL sign_extract) don't bother to appropriately model this with two ops (which the VN insert machinery doesn't handle and which is unlikely to CSE fully). 2021-01-13 Richard Biener <rguenther@suse.de> PR tree-optimization/98640 * tree-ssa-sccvn.c (visit_nary_op): Do not try to handle plus or minus from a truncated operand to be sign-extended. * gcc.dg/torture/pr98640.c: New testcase. (cherry picked from commit ffd28c265e6d611983cd27e9332dc799039a3f04) ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/98640] [10 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 2021-01-12 17:01 [Bug tree-optimization/98640] New: GCC produces incorrect code with -O1 and higher vsevolod.livinskij at frtk dot ru ` (3 preceding siblings ...) 2021-03-03 10:36 ` [Bug tree-optimization/98640] [10 " cvs-commit at gcc dot gnu.org @ 2021-03-03 10:37 ` rguenth at gcc dot gnu.org 4 siblings, 0 replies; 6+ messages in thread From: rguenth at gcc dot gnu.org @ 2021-03-03 10:37 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98640 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Resolution|--- |FIXED Status|ASSIGNED |RESOLVED --- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> --- Fixed. ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-03-03 10:37 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-01-12 17:01 [Bug tree-optimization/98640] New: GCC produces incorrect code with -O1 and higher vsevolod.livinskij at frtk dot ru 2021-01-12 18:45 ` [Bug tree-optimization/98640] [10/11 Regression] GCC produces incorrect code with -O1 and higher since r10-2711-g3ed01d5408045d80 marxin at gcc dot gnu.org 2021-01-13 8:18 ` rguenth at gcc dot gnu.org 2021-01-13 10:13 ` cvs-commit at gcc dot gnu.org 2021-03-03 10:36 ` [Bug tree-optimization/98640] [10 " cvs-commit at gcc dot gnu.org 2021-03-03 10:37 ` rguenth at gcc dot gnu.org
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