Amir Ayupov 3023b15fb1 [BOLT] Support POSSIBLE_PIC_FIXED_BRANCH ...

Detect and support fixed PIC indirect jumps of the following form:
```
movslq  En(%rip), %r1
leaq  PIC_JUMP_TABLE(%rip), %r2
addq  %r2, %r1
jmpq  *%r1
```

with PIC_JUMP_TABLE that looks like following:

```
  JT:  ----------
   E1:| L1 - JT  |
      |----------|
   E2:| L2 - JT  |
      |----------|
      |          |
         ......
   En:| Ln - JT  |
       ----------
```

The code could be produced by compilers, see
https://github.com/llvm/llvm-project/issues/91648.

Test Plan: updated jump-table-fixed-ref-pic.test

Reviewers: maksfb, ayermolo, dcci, rafaelauler

Reviewed By: rafaelauler

Pull Request: https://github.com/llvm/llvm-project/pull/91667

2024-07-18 20:57:05 -07:00

92 KiB

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