Commit Graph

23 Commits

Author SHA1 Message Date
Eric Christopher fe83270ee9 The initial .text section generated in object files was missing the
SHF_ARM_PURECODE flag when being built with the -mexecute-only flag.
All code sections of an ELF must have the flag set for the final .text
section to be execute-only, otherwise the flag gets removed.

A HasData flag is added to MCSection to aid in the determination that
the section is empty. A virtual setTargetSectionFlags is added to
MCELFObjectTargetWriter to allow subclasses to set target specific
section flags to be added to sections which we then use in the ARM
backend to set SHF_ARM_PURECODE.

Patch by Ivan Lozano!

Reviewed By: echristo

Differential Revision: https://reviews.llvm.org/D48792

llvm-svn: 341593
2018-09-06 22:09:31 +00:00
Simon Atanasyan 9f676a7798 [mips] Do not pass redundant IsN64 flag to MCELFObjectTargetWriter. NFC
Now we pass the 'Is64_' flag to the MCELFObjectTargetWriter ctor iif
when we make deal with N64 ABI. So it is redundant to pass additional
'IsN64' flag.

llvm-svn: 313878
2017-09-21 14:04:47 +00:00
Eugene Zelenko 1d43552a40 [MC] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 294369
2017-02-07 23:02:00 +00:00
Rafael Espindola d0e16522c7 Always sort by offset first. NFC.
Every target changing sortRelocs was first calling the parent
implementation. Just run that first.

llvm-svn: 255898
2015-12-17 15:08:24 +00:00
Rafael Espindola ece40ca43d Pass a MCSymbol to needsRelocateWithSymbol.
llvm-svn: 238589
2015-05-29 18:26:09 +00:00
Petar Jovanovic 0380d0b88f Re-enable target-specific relocation table sorting and use it for Mips
Some targets (ie. Mips) have additional rules for ordering the relocation
table entries. Allow them to override generic sortRelocs(), which sorts
entries by Offset.
Then override this function for Mips, to emit HI16 and GOT16 relocations
against the local symbol in pair with the corresponding LO16 relocation.

Patch by Vladimir Stefanovic.

Differential Revision: http://reviews.llvm.org/D7414

llvm-svn: 234883
2015-04-14 13:23:34 +00:00
Ulrich Weigand 46797c6960 [MC] Pass MCSymbolData to needsRelocateWithSymbol
As discussed in a previous checking to support the .localentry
directive on PowerPC, we need to inspect the actual target symbol
in needsRelocateWithSymbol to make the appropriate decision based
on that symbol's st_other bits.

Currently, needsRelocateWithSymbol does not get the target symbol.
However, it is directly available to its sole caller.  This patch
therefore simply extends the needsRelocateWithSymbol by a new
parameter "const MCSymbolData &SD", passes in the target symbol,
and updates all derived implementations.

In particular, in the PowerPC implementation, this patch removes
the FIXME added by the previous checkin.

llvm-svn: 213487
2014-07-20 23:15:06 +00:00
Rafael Espindola 5904e12bfa Completely rewrite ELFObjectWriter::RecordRelocation.
I started trying to fix a small issue, but this code has seen a small fix too
many.

The old code was fairly convoluted. Some of the issues it had:

* It failed to check if a symbol difference was in the some section when
  converting a relocation to pcrel.
* It failed to check if the relocation was already pcrel.
* The pcrel value computation was wrong in some cases (relocation-pc.s)
* It was missing quiet a few cases where it should not convert symbol
  relocations to section relocations, leaving the backends to patch it up.
* It would not propagate the fact that it had changed a relocation to pcrel,
  requiring a quiet nasty work around in ARM.
* It was missing comments.

llvm-svn: 205076
2014-03-29 06:26:49 +00:00
Benjamin Kramer 8817cca5ce Provide basic type safety for array_pod_sort comparators.
This makes using array_pod_sort significantly safer. The implementation relies
on function pointer casting but that should be safe as we're dealing with void*
here.

llvm-svn: 191175
2013-09-22 14:09:50 +00:00
Rafael Espindola 0f2a6fe613 Cleanup relocation sorting for ELF.
We want the order to be deterministic on all platforms. NAKAMURA Takumi
fixed that in r181864. This patch is just two small cleanups:

* Move the function to the cpp file. It is only passed to array_pod_sort.
* Remove the ppc implementation which is now redundant

llvm-svn: 181910
2013-05-15 18:22:01 +00:00
Ulrich Weigand 0684076858 Remove MCELFObjectTargetWriter::adjustFixupOffset hack
Now that PowerPC no longer uses adjustFixupOffset, and no other
back-end (ever?) did, we can remove the infrastructure itself
(incidentally addressing a FIXME to that effect).

llvm-svn: 181895
2013-05-15 15:07:42 +00:00
Jack Carter 1bd90ff6cc This patch reworks how llvm targets set
and update ELF header e_flags.

Currently gathering information such as symbol, 
section and data is done by collecting it in an 
MCAssembler object. From MCAssembler and MCAsmLayout 
objects ELFObjectWriter::WriteObject() forms and 
streams out the ELF object file.

This patch just adds a few members to the MCAssember 
class to store and access the e_flag settings. It 
allows for runtime additions to the e_flag by 
assembler directives. The standalone assembler can 
get to MCAssembler from getParser().getStreamer().getAssembler().

This patch is the generic infrastructure and will be
followed by patches for ARM and Mips for their target 
specific use.

Contributer: Jack Carter
 
llvm-svn: 173882
2013-01-30 02:09:52 +00:00
Adhemerval Zanella f2aceda854 Initial TOC support for PowerPC64 object creation
This patch adds initial PPC64 TOC MC object creation using the small mcmodel
(a single 64K TOC) adding the some TOC relocations (R_PPC64_TOC,
R_PPC64_TOC16, and R_PPC64_TOC16DS).

The addition of 'undefinedExplicitRelSym' hook on 'MCELFObjectTargetWriter'
is meant to avoid the creation of an unreferenced ".TOC." symbol (used in
the .odp creation) as well to set the R_PPC64_TOC relocation target as the
temporary ".TOC." symbol. On PPC64 ABI, the R_PPC64_TOC relocation should
not point to any symbol.

llvm-svn: 166677
2012-10-25 12:27:42 +00:00
Jack Carter 8ad0c272af The ELF relocation record format is different for N64
which many Mips 64 ABIs use than for O64 which many 
if not all other target ABIs use.

Most architectures have the following 64 bit relocation record format:

  typedef struct
  {
    Elf64_Addr   r_offset; /* Address of reference */
    Elf64_Xword  r_info;   /* Symbol index and type of relocation */
  } Elf64_Rel;

  typedef struct
  {
    Elf64_Addr    r_offset;
    Elf64_Xword   r_info;
    Elf64_Sxword  r_addend;
  } Elf64_Rela;

Whereas N64 has the following format:

  typedef struct
  {
    Elf64_Addr    r_offset;/* Address of reference */
    Elf64_Word  r_sym;     /* Symbol index */
    Elf64_Byte  r_ssym;    /* Special symbol */
    Elf64_Byte  r_type3;   /* Relocation type */
    Elf64_Byte  r_type2;   /* Relocation type */
    Elf64_Byte  r_type;    /* Relocation type */
  } Elf64_Rel;

  typedef struct
  {
    Elf64_Addr    r_offset;/* Address of reference */
    Elf64_Word  r_sym;     /* Symbol index */
    Elf64_Byte  r_ssym;    /* Special symbol */
    Elf64_Byte  r_type3;   /* Relocation type */
    Elf64_Byte  r_type2;   /* Relocation type */
    Elf64_Byte  r_type;    /* Relocation type */
    Elf64_Sxword  r_addend;
  } Elf64_Rela;

The structure is the same size, but the r_info data element 
is now 5 separate elements. Besides the content aspects, 
endian byte reordering will be different for the area with 
each element being endianized separately.

I treat this as generic and continue to pass r_type as 
an integer masking and unmasking the byte sized N64 
values for N64 mode. I've implemented this and it causes no 
affect on other current targets.

This passes make check.

Jack

llvm-svn: 159299
2012-06-27 22:28:30 +00:00
Akira Hatanaka 64ad2cf1e4 Add a hook in MCELFObjectTargetWriter to allow targets to sort relocation
entries in the relocation table before they are written out to the file. 

llvm-svn: 153345
2012-03-23 23:06:45 +00:00
Rafael Espindola b120ea2b92 Define trivial destructor inline.
llvm-svn: 147230
2011-12-24 01:53:13 +00:00
Rafael Espindola a2da8aa505 Make GetRelocType pure virtual.
llvm-svn: 147229
2011-12-24 01:36:25 +00:00
Rafael Espindola 38a400df3b Move PPC bits to lib/Target/PowerPC.
llvm-svn: 147124
2011-12-22 01:57:09 +00:00
Rafael Espindola a0124055b1 Move the ARM specific parts of the ELF writer to Target/ARM.
llvm-svn: 147115
2011-12-22 00:37:50 +00:00
Rafael Espindola b264d33854 Move the X86 specific bits of the ELF writer to the Target/X86 directory.
Other targets will follow shortly.

llvm-svn: 147060
2011-12-21 17:30:17 +00:00
Rafael Espindola 1ad4095d6b Reduce the exposure of Triple::OSType in the ELF object writer. This will
avoid including ADT/Triple.h in many places when the target specific bits are
moved.

llvm-svn: 147059
2011-12-21 17:00:36 +00:00
Rafael Espindola fdaae0d16f Move some data to the TargetWriter.
llvm-svn: 122134
2010-12-18 03:27:34 +00:00
Rafael Espindola 6b5e56c2b1 Stub out explicit MCELFObjectTargetWriter interface.
llvm-svn: 122067
2010-12-17 17:45:22 +00:00