public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug tree-optimization/97967] New: Missed optimization opportunity for VRP
@ 2020-11-24 12:32 ishiura-compiler at ml dot kwansei.ac.jp
2021-07-28 20:54 ` [Bug tree-optimization/97967] " pinskia at gcc dot gnu.org
0 siblings, 1 reply; 2+ messages in thread
From: ishiura-compiler at ml dot kwansei.ac.jp @ 2020-11-24 12:32 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97967
Bug ID: 97967
Summary: Missed optimization opportunity for VRP
Product: gcc
Version: 10.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: ishiura-compiler at ml dot kwansei.ac.jp
Target Milestone: ---
We have another VRP related test case for GCC-10.2.0.
We expect A1.c and A2.c should compile to the same codes, but they did
not.
+---------------------------------+---------------------------------+
| A1.c | A2.c |
+---------------------------------+---------------------------------+
|int main (void) |int main (void) |
|{ |{ |
| volatile int a = 1; | volatile int a = 1; |
| | |
| int b = a%2; | a; |
| int t = 200<(short)(-50*b); | int t = 0; |
| | |
| if (t != 0) __builtin_abort(); | if (t != 0) __builtin_abort(); |
| | |
| return 0; | return 0; |
|} |} |
+---------------------------------+---------------------------------+
+-------------------------------+------------------------------+
| A1.s (gcc-10.2.0 A1.c -O3 -S) | A2.s (gcc-10.2.0 A2.c -O3 -S)|
+-------------------------------+------------------------------+
|main: |main: |
|.LFB0: |.LFB0: |
| .cfi_startproc | .cfi_startproc |
| subq $24, %rsp | movl $1, -4(%rsp) |
| .cfi_def_cfa_offset 32 | movl -4(%rsp), %eax |
| movl $1, 12(%rsp) | |
| movl 12(%rsp), %eax | |
| movl %eax, %edx | |
| shrl $31, %edx | |
| addl %edx, %eax | |
| andl $1, %eax | |
| subl %edx, %eax | |
| imull $-50, %eax, %eax | |
| cmpw $200, %ax | |
| jg .L3 | |
| xorl %eax, %eax | xorl %eax, %eax |
| addq $24, %rsp | |
| .cfi_def_cfa_offset 8 | |
| ret | ret |
| .cfi_endproc | .cfi_endproc |
| .section .text.unlikely | |
| .cfi_startproc | |
| .type main.cold, @function| |
|main.cold: | |
|.LFSB0: | |
|.L3: | |
| .cfi_def_cfa_offset 32 | |
| call abort | |
| .cfi_endproc | |
|.LFE0: |.LFE0: |
| .section text.startup | |
| .size main, .-main | .size main, .-main |
| .section .text.unlikely | |
| .size main.cold, .-mai...| |
|.LCOLDE0: | |
| .section .text.startup | |
|.LHOTE0: | |
| .ident "GCC: (GNU) 10.2.0"| .ident "GCC: (GNU) 10.2.0"|
| .section .note.GNU-stac...| .section .note.GNU-stac...|
+--------------------------------------------------------------+
$ gcc -v
using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-pc-linux-gnu/10.2.0/lto-wrapper
target: x86_64-pc-linux-gnu
configure woth: ../configure --enable-languages=c,c++ --prefix=/usr/local
--disable-bootstrap --disable-multilib
thred model: posix
Supported LTO compression algorithms: zlib
gcc version 10.2.0 (GCC)
^ permalink raw reply [flat|nested] 2+ messages in thread
* [Bug tree-optimization/97967] Missed optimization opportunity for VRP
2020-11-24 12:32 [Bug tree-optimization/97967] New: Missed optimization opportunity for VRP ishiura-compiler at ml dot kwansei.ac.jp
@ 2021-07-28 20:54 ` pinskia at gcc dot gnu.org
0 siblings, 0 replies; 2+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-07-28 20:54 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97967
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Target Milestone|--- |11.0
Resolution|--- |FIXED
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed in GCC 11 already.
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2021-07-28 20:54 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-11-24 12:32 [Bug tree-optimization/97967] New: Missed optimization opportunity for VRP ishiura-compiler at ml dot kwansei.ac.jp
2021-07-28 20:54 ` [Bug tree-optimization/97967] " pinskia at gcc dot gnu.org
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).