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* [Bug tree-optimization/60362] New: Failure to optimize away bounds check on switch when range outside bounds is unreachable
@ 2014-02-28 1:26 kvanberendonck at gmail dot com
2014-02-28 1:37 ` [Bug tree-optimization/60362] " pinskia at gcc dot gnu.org
0 siblings, 1 reply; 2+ messages in thread
From: kvanberendonck at gmail dot com @ 2014-02-28 1:26 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60362
Bug ID: 60362
Summary: Failure to optimize away bounds check on switch when
range outside bounds is unreachable
Product: gcc
Version: 4.8.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: kvanberendonck at gmail dot com
Created attachment 32229
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32229&action=edit
The test program
Test program attacked. Compiled with -O3. I had to disassemble the test program
with IDA since gdb gets really confused.
In this program I've spammed __builtin_unreachable(); everywhere to try and get
gcc to optimize away this check it emits after every switch:
cmp byte ptr [rdx+1], 5 ; switch 6 cases
ja sub_1004012B0
gcc isn't getting the hint, and I think it's a bug.
^ permalink raw reply [flat|nested] 2+ messages in thread
* [Bug tree-optimization/60362] Failure to optimize away bounds check on switch when range outside bounds is unreachable
2014-02-28 1:26 [Bug tree-optimization/60362] New: Failure to optimize away bounds check on switch when range outside bounds is unreachable kvanberendonck at gmail dot com
@ 2014-02-28 1:37 ` pinskia at gcc dot gnu.org
0 siblings, 0 replies; 2+ messages in thread
From: pinskia at gcc dot gnu.org @ 2014-02-28 1:37 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60362
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution|--- |DUPLICATE
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Dup of bug 51513.
*** This bug has been marked as a duplicate of bug 51513 ***
^ permalink raw reply [flat|nested] 2+ messages in thread
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2014-02-28 1:26 [Bug tree-optimization/60362] New: Failure to optimize away bounds check on switch when range outside bounds is unreachable kvanberendonck at gmail dot com
2014-02-28 1:37 ` [Bug tree-optimization/60362] " pinskia at gcc dot gnu.org
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