Re: [TCWG CI] Regression caused by gcc: Add new constant data structure.

[Michael Meissner <meissner@linux.ibm.com>]

On Sat, Dec 18, 2021 at 09:12:06PM +0000, ci_notify@linaro.org wrote:
> [TCWG CI] Regression caused by gcc: Add new constant data structure.:
> commit c6756b3bc1d2af1c8e86f0ad1711e9b9134520ba
> Author: Michael Meissner <meissner@linux.ibm.com>
> 
>     Add new constant data structure.
> 
> Results regressed to
> # reset_artifacts:
> -10
> # build_abe binutils:
> -9
> # build_abe stage1 -- --set gcc_override_configure=--disable-libsanitizer --set gcc_override_configure=--disable-multilib --set gcc_override_configure=--with-cpu=cortex-m4 --set gcc_override_configure=--with-mode=thumb --set gcc_override_configure=--with-float=hard:
> -8
> # build_abe newlib:
> -6
> # build_abe stage2 -- --set gcc_override_configure=--disable-libsanitizer --set gcc_override_configure=--disable-multilib --set gcc_override_configure=--with-cpu=cortex-m4 --set gcc_override_configure=--with-mode=thumb --set gcc_override_configure=--with-float=hard:
> -5
> # benchmark -- -Os_mthumb artifacts/build-c6756b3bc1d2af1c8e86f0ad1711e9b9134520ba/results_id:
> 1
> 
> from
> # reset_artifacts:
> -10
> # build_abe binutils:
> -9
> # build_abe stage1 -- --set gcc_override_configure=--disable-libsanitizer --set gcc_override_configure=--disable-multilib --set gcc_override_configure=--with-cpu=cortex-m4 --set gcc_override_configure=--with-mode=thumb --set gcc_override_configure=--with-float=hard:
> -8
> # build_abe newlib:
> -6
> # build_abe stage2 -- --set gcc_override_configure=--disable-libsanitizer --set gcc_override_configure=--disable-multilib --set gcc_override_configure=--with-cpu=cortex-m4 --set gcc_override_configure=--with-mode=thumb --set gcc_override_configure=--with-float=hard:
> -5
> # benchmark -- -Os_mthumb artifacts/build-baseline/results_id:
> 1
> 
> THIS IS THE END OF INTERESTING STUFF.  BELOW ARE LINKS TO BUILDS, REPRODUCTION INSTRUCTIONS, AND THE RAW COMMIT.

Given the files that I changed were in the config/rs6000 directory, and you are
building an arm toolchain, I don't see how this particular change broke your
build.  I believe that it must have been one of the changes after my particular
commit that broke your build.  You should really list all of the commits that
occurred between your last sucessful build and the failure.

Also, it was nearly impossible to trace through the build to find what really
caused the error.

> Full commit (up to 1000 lines):
> <cut>
> commit c6756b3bc1d2af1c8e86f0ad1711e9b9134520ba
> Author: Michael Meissner <meissner@linux.ibm.com>
> Date:   Wed Dec 15 00:56:25 2021 -0500
> 
>     Add new constant data structure.
>     
>     This patch provides the data structure and function to convert a
>     CONST_INT, CONST_DOUBLE, CONST_VECTOR, or VEC_DUPLICATE of a constant) to
>     an array of bytes, half-words, words, and  double words that can be loaded
>     into a 128-bit vector register.
>     
>     The next patches will use this data structure to generate code that
>     generates load of the vector/floating point registers using the XXSPLTIDP,
>     XXSPLTIW, and LXVKQ instructions that were added in power10.
>     
>     2021-12-15  Michael Meissner  <meissner@the-meissners.org>
>     
>     gcc/
>     
>             * config/rs6000/rs6000-protos.h (VECTOR_128BIT_BITS): New macro.
>             (VECTOR_128BIT_BYTES): Likewise.
>             (VECTOR_128BIT_HALF_WORDS): Likewise.
>             (VECTOR_128BIT_WORDS): Likewise.
>             (VECTOR_128BIT_DOUBLE_WORDS): Likewise.
>             (vec_const_128bit_type): New structure type.
>             (vec_const_128bit_to_bytes): New declaration.
>             * config/rs6000/rs6000.c (constant_int_to_128bit_vector): New
>             helper function.
>             (constant_fp_to_128bit_vector): New helper function.
>             (vec_const_128bit_to_bytes): New function.

-- 
Michael Meissner, IBM
PO Box 98, Ayer, Massachusetts, USA, 01432
email: meissner@linux.ibm.com