Commit Graph

13 Commits

Author SHA1 Message Date
Igor Kudrin 657e067bb5 [ARMInstPrinter] Print the target address of a branch instruction
This follows other patches that changed printing immediate values of
branch instructions to target addresses, see D76580 (x86), D76591 (PPC),
D77853 (AArch64).

As observing immediate values might sometimes be useful, they are
printed as comments for branch instructions.

// llvm-objdump -d output (before)
000200b4 <_start>:
   200b4: ff ff ff fa   blx     #-4 <thumb>
000200b8 <thumb>:
   200b8: ff f7 fc ef   blx     #-8 <_start>

// llvm-objdump -d output (after)
000200b4 <_start>:
   200b4: ff ff ff fa   blx     0x200b8 <thumb>         @ imm = #-4
000200b8 <thumb>:
   200b8: ff f7 fc ef   blx     0x200b4 <_start>        @ imm = #-8

// GNU objdump -d.
000200b4 <_start>:
   200b4:       faffffff        blx     200b8 <thumb>
000200b8 <thumb>:
   200b8:       f7ff effc       blx     200b4 <_start>

Differential Revision: https://reviews.llvm.org/D104701
2021-06-30 16:35:28 +07:00
Tobias Hieta 87383e408d [ELF][ARM] Increase default max-page-size from 4096 to 6536
See http://lists.llvm.org/pipermail/llvm-dev/2020-April/140549.html

For the record, GNU ld changed to 64k max page size in 2014
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=7572ca8989ead4c3425a1500bc241eaaeffa2c89
"[RFC] ld/ARM: Increase maximum page size to 64kB"

Android driver forced 4k page size in AArch64 (D55029) and ARM (D77746).

A binary linked with max-page-size=4096 does not run on a system with a
higher page size configured. There are some systems out there that do
this and it leads to the binary getting `Killed!` by the kernel.

In the non-linker-script cases, when linked with -z noseparate-code
(default), the max-page-size increase should not cause any size
difference. There may be some VMA usage differences, though.

Reviewed By: psmith, MaskRay

Differential Revision: https://reviews.llvm.org/D77330
2020-04-18 08:19:45 -07:00
Fangrui Song f0374e7db2 [test] lld/test/: change llvm-objdump single-dash long options to double-dash options 2020-03-15 17:48:36 -07:00
Fangrui Song 71e2ca6e32 [llvm-objdump] -d: print `00000000 <foo>:` instead of `00000000 foo:`
The new behavior matches GNU objdump. A pair of angle brackets makes tests slightly easier.

`.foo:` is not unique and thus cannot be used in a `CHECK-LABEL:` directive.
Without `-LABEL`, the CHECK line can match the `Disassembly of section`
line and causes the next `CHECK-NEXT:` to fail.

```
Disassembly of section .foo:

0000000000001634 .foo:
```

Bdragon: <> has metalinguistic connotation. it just "feels right"

Reviewed By: rupprecht

Differential Revision: https://reviews.llvm.org/D75713
2020-03-05 18:05:28 -08:00
Fangrui Song 024bf27ddf [ELF][ARM] Allow PT_LOAD to have overlapping p_offset ranges on EM_ARM
Port the D64906 technique to ARM. It deletes 3 alignments at
PT_LOAD boundaries for the default case: the size of an arm binary
decreases by at most 12kb.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D66749

llvm-svn: 370049
2019-08-27 11:52:36 +00:00
Fangrui Song 5d4bc1293c [ARM][test] Improve tests
Delete trailing 2>&1 that is not piped to another command.
Add --no-show-raw-insn to objdump -d commands.

llvm-svn: 366676
2019-07-22 11:37:03 +00:00
Fangrui Song 5387c2cd17 [llvm-objdump] Print newlines before and after "Disassembly of section ...:"
This improves readability and the behavior is consistent with GNU objdump.

The new test test/tools/llvm-objdump/X86/disassemble-section-name.s
checks we print newlines before and after "Disassembly of section ...:"

Differential Revision: https://reviews.llvm.org/D61127

llvm-svn: 359668
2019-05-01 10:40:48 +00:00
Fangrui Song b6772b86e2 [ELF] Move `// REQUIRES:` line to the top
llvm-svn: 335676
2018-06-26 22:20:04 +00:00
Benjamin Kramer 61085ca999 Update lld tests after r321526.
llvm-svn: 321529
2017-12-28 17:20:41 +00:00
Rafael Espindola f846ce259a Fix weak symbols on arm and aarch64.
Given

.weak target
 .global _start
_start:
 b target

The intention is that the branch goes to the instruction after the
branch, effectively turning it on a nop.  The branch adds the runtime
PC, but we were adding it statically too.

I noticed the oddity by inspection, but llvm-objdump seems to agree,
since it now prints things like:

b       #-4 <_start+0x4>

llvm-svn: 305212
2017-06-12 18:05:01 +00:00
Rafael Espindola d2a1b944bc Don't check the raw bits in tests.
It is not needed since we have the disassemble.

llvm-svn: 305096
2017-06-09 18:07:34 +00:00
Peter Smith 8339bbd759 [ELF] ARM and AArch64 undefined weak reference values
The ARM 32 and 64-bit ABI does not use 0 for undefined weak references
that are used in PC relative relocations. In particular:
- A branch relocation to an undefined weak resolves to the next
  instruction. Effectively making the branch a no-op
- In all other cases the symbol resolves to the place so that S + A - P
  resolves to A.

Differential Revision: https://reviews.llvm.org/D26240

llvm-svn: 286353
2016-11-09 10:22:29 +00:00
Peter Smith 2227c7f425 [ELF] Do not create interworking thunks for undefined weak references.
An undefined weak reference is given an address of 0 this will
incorrectly trigger the creation of a Thumb to ARM interworking Thunk
if there is a Thumb branch instruction to the symbol. This results in
an error as Thunks only make sense to defined or shared symbols.

We prevent this by detecting an undefined symbol and not creating a thunk
for it.

Differential Revision: https://reviews.llvm.org/D26239

llvm-svn: 285896
2016-11-03 11:49:23 +00:00