[Bug target/48576] wrong code when accessing variables in a large stack frame
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 Eric Gallager changed: What|Removed |Added Status|NEW |RESOLVED CC||egallager at gcc dot gnu.org Resolution|--- |FIXED --- Comment #9 from Eric Gallager --- (In reply to Mikael Pettersson from comment #8) > This got fixed for 4.9+ by Bernd Schmidt's "Fix for reloads_unique_chain_p" > patch in r203596: https://gcc.gnu.org/ml/gcc-patches/2013-10/msg01041.html. > The patch submission describes a problem very similar to this one, so I'm > fairly certain the fix is "proper". > > The patch backports easily to 4.8 and 4.7 and fixes the bug there too. OK, guess this can be closed as FIXED then.
[Bug target/48576] wrong code when accessing variables in a large stack frame
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 --- Comment #8 from Mikael Pettersson mikpelinux at gmail dot com --- This got fixed for 4.9+ by Bernd Schmidt's Fix for reloads_unique_chain_p patch in r203596: https://gcc.gnu.org/ml/gcc-patches/2013-10/msg01041.html. The patch submission describes a problem very similar to this one, so I'm fairly certain the fix is proper. The patch backports easily to 4.8 and 4.7 and fixes the bug there too.
[Bug target/48576] wrong code when accessing variables in a large stack frame
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 --- Comment #7 from Mikael Pettersson mikpe at it dot uu.se 2013-04-13 12:26:24 UTC --- This bug still occurs with gcc 4.9-20130407, 4.8-20130411, and 4.7-20130406.
[Bug target/48576] wrong code when accessing variables in a large stack frame
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 --- Comment #6 from Ramana Radhakrishnan ramana at gcc dot gnu.org 2011-04-20 14:20:10 UTC --- Can an RM reprioritize this one ? It smells of something higher than P3 since this is a wrong code regression from 4.4 ? cheers Ramana
[Bug target/48576] wrong code when accessing variables in a large stack frame
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 --- Comment #5 from Mikael Pettersson mikpe at it dot uu.se 2011-04-16 19:28:54 UTC --- It started with r146817: Author: matz Date: Sun Apr 26 19:35:04 2009 New Revision: 146817 URL: http://gcc.gnu.org/viewcvs?root=gccview=revrev=146817 Log: gcc/ Expand from SSA. ... Diffing the assembly code from r146816 and r146817 shows the error: --- pr48576.s-r146816 2011-04-16 21:06:24.0 +0200 +++ pr48576.s-r146817 2011-04-16 21:06:03.0 +0200 ... bl my_realloc sub r3, fp, #4096 - str r0, [r3, #-44] - str r6, [r0, r5, asl #2] - cmp r4, #1 + str r0, [r3, #-48] + ldr r3, [r3, #-44] + ldr r2, [r3, #-48] + str r4, [r2, r3, asl #2] + cmp r9, #1 ble .L16 ... We wish to save the return value of my_realloc() and immediately make a store with it as an array base pointer and another value as index. Starting with r146817 both values are considered spilled and get reloaded. Both reloads need an intermediate pointer into the frame to reach their locations. The reload of the index value clobbers the intermediate frame pointer needed for the reload of the array base, causing that reload to read an incorrect location.
[Bug target/48576] wrong code when accessing variables in a large stack frame
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 Ramana Radhakrishnan ramana at gcc dot gnu.org changed: What|Removed |Added Keywords||wrong-code Status|UNCONFIRMED |NEW Last reconfirmed||2011.04.13 10:45:15 CC||ramana at gcc dot gnu.org Ever Confirmed|0 |1 --- Comment #4 from Ramana Radhakrishnan ramana at gcc dot gnu.org 2011-04-13 10:45:15 UTC --- Confirmed.
[Bug target/48576] wrong code when accessing variables in a large stack frame
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 Siarhei Siamashka siarhei.siamashka at gmail dot com changed: What|Removed |Added CC||siarhei.siamashka at gmail ||dot com --- Comment #1 from Siarhei Siamashka siarhei.siamashka at gmail dot com 2011-04-12 15:23:02 UTC --- This reminds me about bug 41074 (apparently the same hard to trigger large stack frame related issue).
[Bug target/48576] wrong code when accessing variables in a large stack frame
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 Mikael Pettersson mikpe at it dot uu.se changed: What|Removed |Added CC||mikpe at it dot uu.se --- Comment #2 from Mikael Pettersson mikpe at it dot uu.se 2011-04-12 19:28:30 UTC --- On armv5tel-linux-gnueabi, gcc-4.3.5 and gcc-4.4.5 -march=armv5te -O1 -fno-omit-frame-pointer compile the test case into an a.out that prints xx and exits 0. gcc-4.5.2/4.6.0/4.7 all generate an a.out that segfaults, dropping -fno-omit-frame-pointer makes the a.out print xx and exit 0 again.
[Bug target/48576] wrong code when accessing variables in a large stack frame
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48576 --- Comment #3 from Mikael Pettersson mikpe at it dot uu.se 2011-04-12 22:41:14 UTC --- Created attachment 23969 -- http://gcc.gnu.org/bugzilla/attachment.cgi?id=23969 standalone and reduced test case Succeeds with no output, or segfaults. I'll try a bisection later.
