[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 --- Comment #15 from Alan Modra --- Author: amodra Date: Thu May 5 00:07:27 2016 New Revision: 235914 URL: https://gcc.gnu.org/viewcvs?rev=235914=gcc=rev Log: [RS6000] TARGET_RELOCATABLE For ABI_V4, -mrelocatable and -fPIC both generate position independent code, with some extra "fixup" output for -mrelocatable. The similarity of these two options has led to the situation where the sysv4.h SUBTARGET_OVERRIDE_OPTIONS sets flag_pic on seeing -mrelocatable, and sets TARGET_RELOCATABLE on seeing -fPIC. That prevents LTO from properly optimizing position dependent executables, because the mutual dependence of the flags and the fact that LTO streaming records the state of rs6000_isa_flags, result in flag_pic being set when it shouldn't be. So, don't set TARGET_RELOCATABLE when -fPIC. Places that currently test TARGET_RELOCATABLE can instead test TARGET_RELOCATABLE || (DEFAULT_ABI == ABI_V4 && flag_pic > 1) or since TARGET_RELOCATABLE can only be enabled when ABI_V4, DEFAULT_ABI == ABI_V4 && (TARGET_RELOCATABLE || flag_pic > 1). Also, since flag_pic is set by -mrelocatable, a number of places that currently test TARGET_RELOCATABLE can be simplified. I also made -mrelocatable set TARGET_NO_FP_IN_TOC, allowing TARGET_RELOCATABLE to be removed from ASM_OUTPUT_SPECIAL_POOL_ENTRY_P. Reducing occurrences of TARGET_RELOCATABLE is a good thing. PR target/68662 * config/rs6000/sysv4.h (SUBTARGET_OVERRIDE_OPTIONS): Don't set OPTION_MASK_RELOCATABLE when flag_pic == 2. Set TARGET_NO_FP_IN_TOC for -mrelocatable. (MINIMAL_TOC_SECTION_ASM_OP): Remove redundant TARGET_RELOCATABLE test. (ASM_OUTPUT_SPECIAL_POOL_ENTRY_P): Likewise. (ASM_PREFERRED_EH_DATA_FORMAT): Likewise. * config/rs6000/linux64.h (MINIMAL_TOC_SECTION_ASM_OP): Likewise. (ASM_OUTPUT_SPECIAL_POOL_ENTRY_P): Likewise. (ASM_PREFERRED_EH_DATA_FORMAT): Likewise. * config/rs6000/freebsd64.h (MINIMAL_TOC_SECTION_ASM_OP): Likewise. (ASM_OUTPUT_SPECIAL_POOL_ENTRY_P): Likewise. (ASM_PREFERRED_EH_DATA_FORMAT): Likewise. * config/rs6000/predicates.md (easy_fp_constant): Likewise. * config/rs6000/rs6000.c (rs6000_elf_output_toc_section_asm_op): Likewise. (rs6000_assemble_integer): Update TARGET_RELOCATABLE test. (rs6000_stack_info): Likewise. (rs6000_elf_asm_out_constructor): Likewise. (rs6000_elf_asm_out_destructor): Likewise. (rs6000_elf_declare_function_name): Likewise. * config/rs6000/rs6000.md (load_toc_aix_di): Likewise. * config/rs6000/rs6000.h (MASK_RELOCATABLE, MASK_MINIMAL_TOC): Don't define. Modified: trunk/gcc/ChangeLog trunk/gcc/config/rs6000/freebsd64.h trunk/gcc/config/rs6000/linux64.h trunk/gcc/config/rs6000/predicates.md trunk/gcc/config/rs6000/rs6000.c trunk/gcc/config/rs6000/rs6000.h trunk/gcc/config/rs6000/rs6000.md trunk/gcc/config/rs6000/sysv4.h
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 --- Comment #13 from Alan Modra --- Author: amodra Date: Tue Feb 2 00:01:16 2016 New Revision: 233061 URL: https://gcc.gnu.org/viewcvs?rev=233061=gcc=rev Log: [RS6000] ABI_V4 init of toc section Since 4c4a180d lto has turned off flag_pic when linking a fixed position executable. So flag_pic is zero in rs6000_file_start. However, when we get to actually emitting code, flag_pic may be on again. This results in undefined references to ".LCTOC1". PR target/68662 * config/rs6000/rs6000.c (need_toc_init): New var, set it whenever toc_label_name used. (rs6000_file_start): Don't set up toc section here, (rs6000_output_function_epilogue): do so here instead, (rs6000_xcoff_file_start): and here. * config/rs6000/rs6000.md (load_toc_aix_si): Set need_toc_init. (load_toc_aix_di): Likewise. Modified: trunk/gcc/ChangeLog trunk/gcc/config/rs6000/rs6000.c trunk/gcc/config/rs6000/rs6000.md
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 Alan Modra changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution|--- |FIXED --- Comment #14 from Alan Modra --- Fixed with workaround. https://gcc.gnu.org/ml/gcc-patches/2016-02/msg2.html queued for gcc-7 and 6.1.
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 --- Comment #12 from Peter Bergner --- Should we add an assert somewhere to ensure that flag_pic and TARGET_RELOCATABLE are consistent?
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662
Alan Modra changed:
What|Removed |Added
Status|NEW |ASSIGNED
Assignee|unassigned at gcc dot gnu.org |amodra at gmail dot com
--- Comment #11 from Alan Modra ---
Making the toc initialization in rs6000_file_start not depend on flag_pic, ie.
use
if (DEFAULT_ABI != ABI_DARWIN)
{
switch_to_section (toc_section);
switch_to_section (text_section);
}
and applying Jakub's option handling fix for pr61925 to the rs6000 backend, and
fixing a testcase seems to cure this problem.
However, I'll note that the comment #7 testcase fails to compile foo non-PIC,
even on x86 -m32. Looks like flag_pic and a whole bunch of other flags are not
saved/restored around attribute((optimize())).
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 --- Comment #10 from Alan Modra --- I guess rs6000 needs to implement targetm.override_options_after_change() if we're to keep flag_pic and TARGET_RELOCATABLE consistent.
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 --- Comment #9 from Alan Modra --- For the testcase in comment #7, global_options are inconsistent (*) and wrong when compiling foo. I see flag_pic == 2 there?? (*) In particular, TARGET_RELOCATABLE and flag_pic don't agree. See config/rs6000/sysv4.h SUBTARGET_OVERRIDE_OPTIONS. flag_pic == 2 ought to mean TARGET_RELOCATABLE is true, but TARGET_RELOCATABLE is false. This combination is not recognized in rs6000_emit_move.
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662
--- Comment #7 from Jakub Jelinek ---
Seems like powerpc* has lots of other issues related to mixing pic and non-pic
code. E.g.
int x;
int
foo (void)
{
return x;
}
__attribute__((optimize ("PIC"))) int
bar (void)
{
return x;
}
seems to ICE due to endless recursion with -O2 -m32 (every force_reg causes
another force_reg, at least in x86_64-linux -> powerpc64-linux cross).
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 --- Comment #8 from Peter Bergner --- (In reply to Jakub Jelinek from comment #7) > seems to ICE due to endless recursion with -O2 -m32 (every force_reg causes > another force_reg, at least in x86_64-linux -> powerpc64-linux cross). I see a similar failure on a native compile too.
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 --- Comment #5 from David Edelsohn --- Unconditionally generating toc_label_name is okay with me, but I thought that Alan commented it was not sufficient in Comment #2.
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 --- Comment #6 from Jakub Jelinek --- Author: jakub Date: Tue Jan 26 19:53:37 2016 New Revision: 232844 URL: https://gcc.gnu.org/viewcvs?rev=232844=gcc=rev Log: PR target/68662 * config/rs6000/rs6000.c (rs6000_option_override_internal): Initialize toc_label_name unconditionally. (rs6000_emit_load_toc_table): Call ggc_strdup on toc_label_name for SYMBOL_REF string. Use toc_label_name instead of constructing LCTOC1. (rs6000_elf_declare_function_name): Use toc_label_name instead of constructing LCTOC1. Modified: trunk/gcc/ChangeLog trunk/gcc/config/rs6000/rs6000.c
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 Jakub Jelinek changed: What|Removed |Added CC||jakub at gcc dot gnu.org --- Comment #4 from Jakub Jelinek --- Created attachment 37475 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37475=edit gcc6-pr68662.patch So what about this untested patch? ASM_GENERATE_INTERNAL_LABEL doesn't look to be too expensive to do unconditionally once, and for GC sanity it needs to go through ggc_strdup anyway (it is invalid to refer to non-GC allocated strings in GTY const char * fields that are not skipped by GC).
[Bug target/68662] [6 regression] FAIL: gcc.dg/lto/20090210 c_lto_20090210_0.o-c_lto_20090210_1.o link, -O2 -flto -flto-partition=none -fuse-linker-plugin -fno-fat-lto-objects
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68662 Jan Hubicka changed: What|Removed |Added Component|lto |target --- Comment #3 from Jan Hubicka --- OK, this looks more like target issue so I am changing component. flag_pic is a global option and it is merged by the lto wrapper and corrected based on the linker output. Because static executable is built, flag_pic should be 0. Targets must be ready for -fPIC being different at compile time and link time and ought to honor the link time setting...
