[Bug target/101220] New: arm: iwmmxt2: generating bad assembler ?

[Bug target/101220] New: arm: iwmmxt2: generating bad assembler ?

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101220

            Bug ID: 101220
           Summary: arm: iwmmxt2: generating bad assembler ?
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

For this C source code:


struct Node FirstNode_t;
struct Node {
  int Pi;
  int BestPi
} FirstNode() {
  FirstNode_t.Pi = FirstNode_t.BestPi = 0;
}

Compiled on a raspberry pi cross compiler like this:

$ /home/dcb/raspberrypi/results/bin/arm-linux-gnueabihf-gcc -c -O3
-march=iwmmxt2 -c bug731.c

does this:

/tmp/cccOc0OE.s: Assembler messages:
/tmp/cccOc0OE.s:25: Error: selected processor does not support `wldrd wr0,.L3'
in ARM mode
/tmp/cccOc0OE.s:28: Error: selected processor does not support `wstrd wr0,[r3]'
in ARM mode

Cross compiler is

$ /home/dcb/raspberrypi/results/bin/arm-linux-gnueabihf-gcc -v
Using built-in specs.
COLLECT_GCC=/home/dcb/raspberrypi/results/bin/arm-linux-gnueabihf-gcc
COLLECT_LTO_WRAPPER=/home/dcb/raspberrypi/results/libexec/gcc/arm-linux-gnueabihf/12.0.0/lto-wrapper
Target: arm-linux-gnueabihf
Configured with: /home/dcb/gcc/trunk.git/configure
--prefix=/home/dcb/raspberrypi/results/ --target=arm-linux-gnueabihf
--enable-languages=c,c++,fortran --with-arch=armv6 --with-fpu=vfp
--with-float=hard --disable-multilib --enable-checking=df,extra,fold,rtl,yes
--with-pkgversion=7dcf139a2b8e1c53
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 12.0.0 20210624 (experimental) (7dcf139a2b8e1c53)

[Bug target/101220] arm: iwmmxt2: generating bad assembler ?

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101220

--- Comment #1 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
The same problem exists in gcc-10 and gcc-11 (gcc-9 does not generate the
wldrd/wstrd insructions), but I think this is a gas bug rather than a bug in
gcc.  The output from the gcc-12 compiler does assemble without problems with
binutils-2.32, but fails with 2.36 (I haven't built intervening versions to
narrow it down yet).

[Bug target/101220] arm: iwmmxt2: generating bad assembler ?

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101220

--- Comment #2 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
Was broken by the binutils commit f439988037a589de3798f44e7268301adaec21a9

[Bug target/101220] arm: iwmmxt2: generating bad assembler ?

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101220

Richard Earnshaw <rearnsha at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |MOVED

--- Comment #3 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
Moved to binutils bugzilla:
https://sourceware.org/bugzilla/show_bug.cgi?id=28031

[Bug target/101220] arm: iwmmxt2: generating bad assembler ?

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101220

--- Comment #4 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
FTR I've committed fixes to binutils on the master and 2.36 branches.  Although
I think this affects binutils 2.34 and later older branches of binutils are
no-longer maintained.