From 9d7b48dc6e8415e95f5228a6f66b414827eb0204 Mon Sep 17 00:00:00 2001 From: Andrew Burgess Date: Sat, 22 Nov 2014 23:25:17 +0000 Subject: [PATCH] AVR/ld: Propagate link-relax elf header flag correctly. The AVR target has an elf header flag to indicate if an object was assembler ready for linker relaxation. If a partial link is performed then it is important that the link-relax flag in the output object is set correctly, otherwise, during the final link, we might try to perform linker relaxation on code that was not assembled suitably. As the link-relax elf header covers the entire object file we must be conservative when setting the flag in the output object, so, for a partial link, any input object that does not have the link-relax flag set will cause the output object to also not have the link-relax flag set. This conservative approach could be softened in future, we only need to disable the link relax flag if an input file is not marked link-relax ready, and the input file contains a relaxable section. However, I've left this optimisation for a later day. For the final link I've overloaded the use of the link-relax elf header flag, in a final executable, the flag now indicates if the executable was built with linker relaxation on or not. ld/ChangeLog: * emultempl/avrelf.em: Add include of elf/avr.h. (avr_finish): New function. (LDEMUL_FINISH): Added. ld/testsuite/ChangeLog: * ld-avr/relax-elf-flags-01.d: New file. * ld-avr/relax-elf-flags-02.d: New file. * ld-avr/relax-elf-flags-03.d: New file. * ld-avr/relax-elf-flags-04.d: New file. * ld-avr/relax-elf-flags-05.d: New file. * ld-avr/relax-elf-flags-06.d: New file. * ld-avr/relax-elf-flags-07.d: New file. * ld-avr/relax-elf-flags-08.d: New file. * ld-avr/relax-elf-flags-a.s: New file. * ld-avr/relax-elf-flags-b.s: New file. --- ld/ChangeLog | 6 ++++++ ld/emultempl/avrelf.em | 37 ++++++++++++++++++++++++++++++++ ld/testsuite/ChangeLog | 13 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-01.d | 12 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-02.d | 12 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-03.d | 12 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-04.d | 12 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-05.d | 12 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-06.d | 12 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-07.d | 12 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-08.d | 12 +++++++++++ ld/testsuite/ld-avr/relax-elf-flags-a.s | 4 ++++ ld/testsuite/ld-avr/relax-elf-flags-b.s | 4 ++++ 13 files changed, 160 insertions(+) create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-01.d create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-02.d create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-03.d create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-04.d create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-05.d create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-06.d create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-07.d create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-08.d create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-a.s create mode 100644 ld/testsuite/ld-avr/relax-elf-flags-b.s diff --git a/ld/ChangeLog b/ld/ChangeLog index 154def7..0b2f058 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,9 @@ +2014-12-23 Andrew Burgess + + * emultempl/avrelf.em: Add include of elf/avr.h. + (avr_finish): New function. + (LDEMUL_FINISH): Added. + 2014-12-23 Alan Modra * ldexp.c (update_definedness): Return false if script symbol is diff --git a/ld/emultempl/avrelf.em b/ld/emultempl/avrelf.em index 170dc3e..f4e2654 100644 --- a/ld/emultempl/avrelf.em +++ b/ld/emultempl/avrelf.em @@ -28,6 +28,7 @@ fragment <link.next) + { + /* Don't let the linker stubs prevent the final object being + marked as link-relax ready. */ + if ((elf_elfheader (abfd)->e_flags + & EF_AVR_LINKRELAX_PREPARED) == 0 + && abfd != stub_file->the_bfd) + { + avr_link_relax = FALSE; + break; + } + } + } + else + { + avr_link_relax = RELAXATION_ENABLED; + } + + abfd = link_info.output_bfd; + if (avr_link_relax) + elf_elfheader (abfd)->e_flags |= EF_AVR_LINKRELAX_PREPARED; + else + elf_elfheader (abfd)->e_flags &= ~EF_AVR_LINKRELAX_PREPARED; + + finish_default (); +} EOF @@ -274,3 +310,4 @@ LDEMUL_BEFORE_PARSE=avr_elf_before_parse LDEMUL_BEFORE_ALLOCATION=avr_elf_${EMULATION_NAME}_before_allocation LDEMUL_AFTER_ALLOCATION=avr_elf_after_allocation LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=avr_elf_create_output_section_statements +LDEMUL_FINISH=avr_finish diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog index cfc0284..fdef038 100644 --- a/ld/testsuite/ChangeLog +++ b/ld/testsuite/ChangeLog @@ -1,3 +1,16 @@ +2014-12-23 Andrew Burgess + + * ld-avr/relax-elf-flags-01.d: New file. + * ld-avr/relax-elf-flags-02.d: New file. + * ld-avr/relax-elf-flags-03.d: New file. + * ld-avr/relax-elf-flags-04.d: New file. + * ld-avr/relax-elf-flags-05.d: New file. + * ld-avr/relax-elf-flags-06.d: New file. + * ld-avr/relax-elf-flags-07.d: New file. + * ld-avr/relax-elf-flags-08.d: New file. + * ld-avr/relax-elf-flags-a.s: New file. + * ld-avr/relax-elf-flags-b.s: New file. + 2014-12-23 Alan Modra * ld-powerpc/sdabase.s, diff --git a/ld/testsuite/ld-avr/relax-elf-flags-01.d b/ld/testsuite/ld-avr/relax-elf-flags-01.d new file mode 100644 index 0000000..6cf4920 --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-01.d @@ -0,0 +1,12 @@ +#name: AVR, check link-relax flag is set on partial link +#as: -mmcu=avrxmega2 +#ld: -r -mavrxmega2 +#source: relax-elf-flags-a.s -mlink-relax +#source: relax-elf-flags-b.s -mlink-relax +#readelf: -h +#target: avr-*-* + +ELF Header: +#... + Flags: 0xe6, avr:102, link-relax +#... \ No newline at end of file diff --git a/ld/testsuite/ld-avr/relax-elf-flags-02.d b/ld/testsuite/ld-avr/relax-elf-flags-02.d new file mode 100644 index 0000000..6a008bd --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-02.d @@ -0,0 +1,12 @@ +#name: AVR, check link-relax flag is clear on partial link (first file) +#as: -mmcu=avrxmega2 +#ld: -r -mavrxmega2 +#source: relax-elf-flags-a.s +#source: relax-elf-flags-b.s -mlink-relax +#readelf: -h +#target: avr-*-* + +ELF Header: +#... + Flags: 0x66, avr:102 +#... \ No newline at end of file diff --git a/ld/testsuite/ld-avr/relax-elf-flags-03.d b/ld/testsuite/ld-avr/relax-elf-flags-03.d new file mode 100644 index 0000000..3d2a70d --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-03.d @@ -0,0 +1,12 @@ +#name: AVR, check link-relax flag is clear on partial link, second file. +#as: -mmcu=avrxmega2 +#ld: -r -mavrxmega2 +#source: relax-elf-flags-a.s -mlink-relax +#source: relax-elf-flags-b.s +#readelf: -h +#target: avr-*-* + +ELF Header: +#... + Flags: 0x66, avr:102 +#... \ No newline at end of file diff --git a/ld/testsuite/ld-avr/relax-elf-flags-04.d b/ld/testsuite/ld-avr/relax-elf-flags-04.d new file mode 100644 index 0000000..e2a9bb6 --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-04.d @@ -0,0 +1,12 @@ +#name: AVR, check link-relax flag is clear on partial link (both files) +#as: -mmcu=avrxmega2 +#ld: -r -mavrxmega2 +#source: relax-elf-flags-a.s +#source: relax-elf-flags-b.s +#readelf: -h +#target: avr-*-* + +ELF Header: +#... + Flags: 0x66, avr:102 +#... \ No newline at end of file diff --git a/ld/testsuite/ld-avr/relax-elf-flags-05.d b/ld/testsuite/ld-avr/relax-elf-flags-05.d new file mode 100644 index 0000000..8c41e8d --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-05.d @@ -0,0 +1,12 @@ +#name: AVR, check link-relax flag is set final link (no inputs relaxable) +#as: -mmcu=avrxmega2 +#ld: -relax -mavrxmega2 +#source: relax-elf-flags-a.s +#source: relax-elf-flags-b.s +#readelf: -h +#target: avr-*-* + +ELF Header: +#... + Flags: 0xe6, avr:102, link-relax +#... \ No newline at end of file diff --git a/ld/testsuite/ld-avr/relax-elf-flags-06.d b/ld/testsuite/ld-avr/relax-elf-flags-06.d new file mode 100644 index 0000000..5d8e3c1 --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-06.d @@ -0,0 +1,12 @@ +#name: AVR, check link-relax flag is set final link (first input relaxable) +#as: -mmcu=avrxmega2 +#ld: -relax -mavrxmega2 +#source: relax-elf-flags-a.s -mlink-relax +#source: relax-elf-flags-b.s +#readelf: -h +#target: avr-*-* + +ELF Header: +#... + Flags: 0xe6, avr:102, link-relax +#... \ No newline at end of file diff --git a/ld/testsuite/ld-avr/relax-elf-flags-07.d b/ld/testsuite/ld-avr/relax-elf-flags-07.d new file mode 100644 index 0000000..25b70e7 --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-07.d @@ -0,0 +1,12 @@ +#name: AVR, check link-relax flag is set final link (both inputs relaxable) +#as: -mmcu=avrxmega2 +#ld: -relax -mavrxmega2 +#source: relax-elf-flags-a.s -mlink-relax +#source: relax-elf-flags-b.s -mlink-relax +#readelf: -h +#target: avr-*-* + +ELF Header: +#... + Flags: 0xe6, avr:102, link-relax +#... \ No newline at end of file diff --git a/ld/testsuite/ld-avr/relax-elf-flags-08.d b/ld/testsuite/ld-avr/relax-elf-flags-08.d new file mode 100644 index 0000000..0b2152a --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-08.d @@ -0,0 +1,12 @@ +#name: AVR, check link-relax flag is clear final link (both inputs relaxable) +#as: -mmcu=avrxmega2 +#ld: -mavrxmega2 +#source: relax-elf-flags-a.s -mlink-relax +#source: relax-elf-flags-b.s -mlink-relax +#readelf: -h +#target: avr-*-* + +ELF Header: +#... + Flags: 0x66, avr:102 +#... \ No newline at end of file diff --git a/ld/testsuite/ld-avr/relax-elf-flags-a.s b/ld/testsuite/ld-avr/relax-elf-flags-a.s new file mode 100644 index 0000000..af543e1 --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-a.s @@ -0,0 +1,4 @@ + .text + .global _start +_start: + nop diff --git a/ld/testsuite/ld-avr/relax-elf-flags-b.s b/ld/testsuite/ld-avr/relax-elf-flags-b.s new file mode 100644 index 0000000..59ca0cc --- /dev/null +++ b/ld/testsuite/ld-avr/relax-elf-flags-b.s @@ -0,0 +1,4 @@ + .text + .global func +func: + nop -- 2.7.4