Commit Graph

7 Commits

Author SHA1 Message Date
Alex Brachet d54d4f9905 [llvm-objcopy] Changed command line parsing errors
Summary: Tidied up errors during command line parsing to be more consistent with the rest of llvm-objcopy errors.

Reviewers: jhenderson, rupprecht, espindola, alexshap

Reviewed By: jhenderson, rupprecht

Subscribers: emaste, arichardson, MaskRay, llvm-commits, jakehehrlich

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62973

llvm-svn: 363350
2019-06-14 02:04:02 +00:00
Fangrui Song aa1f2c50a8 [llvm-objcopy] Simplify SHT_NOBITS -> SHT_PROGBITS promotion
GNU objcopy uses bfd_elf_get_default_section_type to decide the candidate section type,
which roughly translates to our [a] (I assume SEC_COMMON implies SHF_ALLOC):

  (!(Sec.Flags & ELF::SHF_ALLOC) || Flags & (SectionFlag::SecContents | SectionFlag::SecLoad)))

Then, it updates the section type in bfd/elf.c:elf_fake_sections if:

  if (this_hdr->sh_type == SHT_NULL)
    this_hdr->sh_type = sh_type; // common case
  else if (this_hdr->sh_type == SHT_NOBITS
           && sh_type == SHT_PROGBITS
           && (asect->flags & SEC_ALLOC) != 0)  // uncommon case
    ...
    this_hdr->sh_type = sh_type;

If the following condition is met the uncommon branch is executed:

  if (elf_section_type (osec) == SHT_NULL
      && (osec->flags == isec->flags
	  || (final_link
	      && ((osec->flags ^ isec->flags)
		  & ~(SEC_LINK_ONCE | SEC_LINK_DUPLICATES | SEC_RELOC)) == 0)))

I suggest we just ignore this clause and follow the common case
behavior, which is done in this patch. Rationales to do so:

If --set-section-flags is a no-op (osec->flags == isec->flags)
(corresponds to the "readonly" test in set-section-flags.test), GNU
objcopy will require (Sec.Flags & ELF::SHF_ALLOC). [a] is essentially:

  Flags & (SectionFlag::SecContents | SectionFlag::SecLoad)

This special case is not really useful. Non-SHF_ALLOC SHT_NOBITS
sections do not make much sense and it doesn't matter if they are
SHT_NOBITS or SHT_PROGBITS.

For all other RUN lines in set-section-flags.test, the new behavior
matches GNU objcopy, i.e. this patch improves compatibility.

Differential Revision: https://reviews.llvm.org/D60189

llvm-svn: 359639
2019-05-01 00:39:31 +00:00
James Henderson f5b181e16d [NFC] Address missed review comment for test
Reviewed by: grimar

Differential Revision: https://reviews.llvm.org/D60200

llvm-svn: 357594
2019-04-03 14:50:50 +00:00
James Henderson d931cf3e46 [llvm-objcopy] Make section rename/set flags case-insensitive
This fixes https://bugs.llvm.org/show_bug.cgi?id=41305. GNU objcopy
--set-section-flags/--rename-section flags are case-insensitive, so this
patch updates llvm-objcopy to match.

Reviewed by: grimar

Differential Revision: https://reviews.llvm.org/D60200

llvm-svn: 357590
2019-04-03 14:40:27 +00:00
Jordan Rupprecht 017deaf1ae [llvm-objcopy] Change SHT_NOBITS to SHT_PROBITS for some --set-section-flags
Summary:
Some flags accepted by --set-section-flags and --rename-section can change a SHT_NOBITS section to a SHT_PROGBITS section. Note that none of them can change a SHT_PROGBITS to SHT_NOBITS.

The full list (found via experimentation of individually setting each flag) that does this is: contents, load, noload, code, data, rom, and debug.

This was found by testing llvm-objcopy with the gnu binutils test suite, specifically this test case: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=blob;f=binutils/testsuite/binutils-all/copy-1.d;h=f2b0d9e90df738c2891b4d5c7b62f62894b556ca;hb=HEAD

Reviewers: jhenderson, grimar, jakehehrlich, alexshap, espindola

Reviewed By: jhenderson

Subscribers: emaste, arichardson, MaskRay, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59958

llvm-svn: 357492
2019-04-02 16:49:56 +00:00
Jordan Rupprecht ad29d29130 [llvm-objcopy][NFC] More error cleanup
Summary:
This removes calls to `error()`/`reportError()` in the main driver (llvm-objcopy.cpp) as well as the associated argv-parsing (CopyConfig.cpp). `logAllUnhandledErrors()` is now the main way to print errors.

There are still a few uses from within the per-arch drivers, so we can't delete them yet... but almost!

Reviewers: jhenderson, alexshap, espindola

Reviewed By: jhenderson

Subscribers: emaste, arichardson, jakehehrlich, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58316

llvm-svn: 354600
2019-02-21 17:05:19 +00:00
Jordan Rupprecht c892741e74 [llvm-objcopy] Implement --set-section-flags.
Summary:
--set-section-flags is used to change the section flags (e.g. SHF_ALLOC) for given sections. The flags allowed are the same from the existing --rename-section=.old=.new[,flags] feature.

Additionally, make sure that --set-section-flag cannot be used with --rename-section (either the source or destination), since --rename-section accepts flags. This avoids ambiguity for something like "--rename-section=.foo=.bar,alloc --set-section-flag=.bar,code".

Reviewers: jhenderson, jakehehrlich, alexshap, espindola

Reviewed By: jhenderson, jakehehrlich

Subscribers: llvm-commits, emaste, arichardson

Differential Revision: https://reviews.llvm.org/D57198

llvm-svn: 352505
2019-01-29 15:05:38 +00:00