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Merged
merged 6 commits into from
Jun 18, 2022

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Zephyr-specific patches for zephyr-gcc-12.1.0

nashif and others added 3 commits June 15, 2022 21:27
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
This adds the necessary bits to build for x86_64-zephyr-elf with
multilib support (m32 and m64), following the x86_64-*-linux*
footsteps.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This is a porting of the patches in meta-zephyr-sdk to gcc-8.2.0

We merge:
	recipes-devtools/gcc/files/libgcc-t-zephyr.patch
	recipes-devtools/gcc/files/config-x86-multi-gcc.patch
	recipes-devtools/gcc/files/x86-multilib.patch
	recipes-devtools/gcc/files/config-libgcc-softfp.patch

Into one patch.  There are some changes to libgcc/config.host in
gcc-8.2.0 that required updating the patch to that file.  There's some
common code to handle soft-fp on x86.  In gcc-8.2.0 that common code
would by default get applied to a zephyr build.  However the common
code doesn't handle soft-fp the way we need so we add
i[34567]86-zephyr-elf as a special case similar to
i[34567]86-*-elfiamcu.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
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stephanosio commented Jun 17, 2022

TODO: Rework the RISC-V multilib patch from the scratch to reflect the Zicsr and Zifencei changes; drop the use of the multilib-generator script since the multilib configuration is now much more complex.

UPDATE: Done (40f0bc5). Note that the new multilib script (t-zephyr) makes use of some substitution magickery to vastly improve the readability and maintainability of the supported RISC-V architecture variants. Also note that the _zicsr_zifencei suffix has been added to all "I" extension variants because the target RISC-V spec has been updated to 20191213.

Martin Aberg and others added 3 commits June 18, 2022 03:52
Adds the necessary bits for building libraries for the LEON -mcpu
targets.

Signed-off-by: Martin Åberg <martin.aberg@gaisler.com>
This fixes soft-float build for x86 32-bit (-m32 -msoft-float)
under x86_64-zephyr-elf multilib build. This now actually
includes the soft float functions.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit adds a Zephyr-specific multilib configuration file for the
RISC-V architecture in order to ensure that the multilibs are built for
all RISC-V targets supported in the upstream Zephyr RTOS.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
@stephanosio stephanosio force-pushed the zephyr-gcc-12.1.0_patches branch from 5b0b3b4 to 40f0bc5 Compare June 17, 2022 18:59
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@stephanosio stephanosio merged commit 6c9643f into zephyr-gcc-12.1.0 Jun 18, 2022
@stephanosio stephanosio deleted the zephyr-gcc-12.1.0_patches branch June 18, 2022 16:44
nashif pushed a commit that referenced this pull request May 31, 2025
…o_debug_section [PR116614]

cat abc.C
  #define A(n) struct T##n {} t##n;
  #define B(n) A(n##0) A(n##1) A(n##2) A(n##3) A(n##4) A(n##5) A(n##6) A(n##7) A(n##8) A(n##9)
  #define C(n) B(n##0) B(n##1) B(n##2) B(n##3) B(n##4) B(n##5) B(n##6) B(n##7) B(n##8) B(n##9)
  #define D(n) C(n##0) C(n##1) C(n##2) C(n##3) C(n##4) C(n##5) C(n##6) C(n##7) C(n##8) C(n##9)
  #define E(n) D(n##0) D(n##1) D(n##2) D(n##3) D(n##4) D(n##5) D(n##6) D(n##7) D(n##8) D(n##9)
  E(1) E(2) E(3)
  int main () { return 0; }
./xg++ -B ./ -o abc{.o,.C} -flto -flto-partition=1to1 -O2 -g -fdebug-types-section -c
./xgcc -B ./ -o abc{,.o} -flto -flto-partition=1to1 -O2
(not included in testsuite as it takes a while to compile) FAILs with
lto-wrapper: fatal error: Too many copied sections: Operation not supported
compilation terminated.
/usr/bin/ld: error: lto-wrapper failed
collect2: error: ld returned 1 exit status

The following patch fixes that.  Most of the 64K+ section support for
reading and writing was already there years ago (and especially reading used
quite often already) and a further bug fixed in it in the PR104617 fix.

Yet, the fix isn't solely about removing the
  if (new_i - 1 >= SHN_LORESERVE)
    {
      *err = ENOTSUP;
      return "Too many copied sections";
    }
5 lines, the missing part was that the function only handled reading of
the .symtab_shndx section but not copying/updating of it.
If the result has less than 64K-epsilon sections, that actually wasn't
needed, but e.g. with -fdebug-types-section one can exceed that pretty
easily (reported to us on WebKitGtk build on ppc64le).
Updating the section is slightly more complicated, because it basically
needs to be done in lock step with updating the .symtab section, if one
doesn't need to use SHN_XINDEX in there, the section should (or should be
updated to) contain SHN_UNDEF entry, otherwise needs to have whatever would
be overwise stored but couldn't fit.  But repeating due to that all the
symtab decisions what to discard and how to rewrite it would be ugly.

So, the patch instead emits the .symtab_shndx section (or sections) last
and prepares the content during the .symtab processing and in a second
pass when going just through .symtab_shndx sections just uses the saved
content.

2024-09-07  Jakub Jelinek  <jakub@redhat.com>

	PR lto/116614
	* simple-object-elf.c (SHN_COMMON): Align comment with neighbouring
	comments.
	(SHN_HIRESERVE): Use uppercase hex digits instead of lowercase for
	consistency.
	(simple_object_elf_find_sections): Formatting fixes.
	(simple_object_elf_fetch_attributes): Likewise.
	(simple_object_elf_attributes_merge): Likewise.
	(simple_object_elf_start_write): Likewise.
	(simple_object_elf_write_ehdr): Likewise.
	(simple_object_elf_write_shdr): Likewise.
	(simple_object_elf_write_to_file): Likewise.
	(simple_object_elf_copy_lto_debug_section): Likewise.  Don't fail for
	new_i - 1 >= SHN_LORESERVE, instead arrange in that case to copy
	over .symtab_shndx sections, though emit those last and compute their
	section content when processing associated .symtab sections.  Handle
	simple_object_internal_read failure even in the .symtab_shndx reading
	case.

(cherry picked from commit bb8dd09)
nashif pushed a commit that referenced this pull request May 31, 2025
Update test case for armv8.1-m.main that supports conditional
arithmetic.

armv7-m:
        push    {r4, lr}
        ldr     r4, .L6
        ldr     r4, [r4]
        lsls    r4, r4, #29
        it      mi
        addmi   r2, r2, #1
        bl      bar
        movs    r0, #0
        pop     {r4, pc}

armv8.1-m.main:
        push    {r3, r4, r5, lr}
        ldr     r4, .L5
        ldr     r5, [r4]
        tst     r5, #4
        csinc   r2, r2, r2, eq
        bl      bar
        movs    r0, #0
        pop     {r3, r4, r5, pc}

gcc/testsuite/ChangeLog:

	* gcc.target/arm/epilog-1.c: Use check-function-bodies.

Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>
(cherry picked from commit ec86e87)
nashif pushed a commit that referenced this pull request May 31, 2025
In r14.2.0-376-g724446556e5, I accidentally introduced a regression in
the expected assembler as the csinc instruction was not used for
armv8.1-m.main.

The generated assembler for armv8.1-m.main is:
        push    {r3, r4, r5, lr}
        ldr     r4, .L5
        ldr     r5, [r4]
        adds    r4, r2, #1
        tst     r5, #4
        it      ne
        movne   r2, r4
        bl      bar
        movs    r0, #0
        pop     {r3, r4, r5, pc}

gcc/testsuite/ChangeLog:

	* gcc.target/arm/epilog-1.c: Corrected armv8.1.m-main asm.

Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>
nashif pushed a commit that referenced this pull request May 31, 2025
Whenever C1 and C2 are integer constants, X is of a wrapping type, and
cmp is a relational operator, the expression X +- C1 cmp C2 can be
simplified in the following cases:

(a) If cmp is <= and C2 -+ C1 == +INF(1), we can transform the initial
comparison in the following way:
   X +- C1 <= C2
   -INF <= X +- C1 <= C2 (add left hand side which holds for any X, C1)
   -INF -+ C1 <= X <= C2 -+ C1 (add -+C1 to all 3 expressions)
   -INF -+ C1 <= X <= +INF (due to (1))
   -INF -+ C1 <= X (eliminate the right hand side since it holds for any X)

(b) By analogy, if cmp if >= and C2 -+ C1 == -INF(1), use the following
sequence of transformations:

   X +- C1 >= C2
   +INF >= X +- C1 >= C2 (add left hand side which holds for any X, C1)
   +INF -+ C1 >= X >= C2 -+ C1 (add -+C1 to all 3 expressions)
   +INF -+ C1 >= X >= -INF (due to (1))
   +INF -+ C1 >= X (eliminate the right hand side since it holds for any X)

(c) The > and < cases are negations of (a) and (b), respectively.

This transformation allows to occasionally save add / sub instructions,
for instance the expression

3 + (uint32_t)f() < 2

compiles to

cmn     w0, #4
cset    w0, ls

instead of

add     w0, w0, 3
cmp     w0, 2
cset    w0, ls

on aarch64.

Testcases that go together with this patch have been split into two
separate files, one containing testcases for unsigned variables and the
other for wrapping signed ones (and thus compiled with -fwrapv).
Additionally, one aarch64 test has been adjusted since the patch has
caused the generated code to change from

cmn     w0, #2
csinc   w0, w1, wzr, cc   (x < -2)

to

cmn     w0, #3
csinc   w0, w1, wzr, cs   (x <= -3)

This patch has been bootstrapped and regtested on aarch64, x86_64, and
i386, and additionally regtested on riscv32.

gcc/ChangeLog:

	PR tree-optimization/116024
	* match.pd: New transformation around integer comparison.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/pr116024-2.c: New test.
	* gcc.dg/tree-ssa/pr116024-2-fwrapv.c: Ditto.
	* gcc.target/aarch64/gtu_to_ltu_cmp_1.c: Adjust.
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4 participants