Commit Graph

7 Commits

Author SHA1 Message Date
Amir Ayupov 6bb26fcb20 [BOLT] removeAllSuccessors: handle multiple edges between basic blocks
Summary:
If `addUnknownControlFlow` in `BinaryFunction::postProcessIndirectBranches`
is invoked with a basic block that has multiple edges to the same successor,
it leads to an assertion in `BinaryBasicBlock::removePredecessor`.

For basic blocks with multiple edges to the same successor, the default
behavior of removePredecessor is to remove all occurrences of the
predecessor block in its predecessor list (Multiple=true).

Example:
```A -> B (two edges)

A->removeAllSuccessors()
  for each successor of block A: // B twice
  // this removes both occurrences of A in B's predecessors list
  B->removePredecessor(A);
  // this invocation triggers an assert as A is no longer in B's
  // predecessor list
  B->removePredecessor(A);
```
This issue is not fixed by NormalizeCFG as `removeAllSuccessor` is called
earlier (from `buildCFG` -> `postProcessIndirectBranches`).

Solve this issue by collecting the successors into a set (`SmallPtrSet`) first,
before invoking `SuccessorBB->removePredecessor(this)`.

GitHub issue: https://github.com/facebookincubator/BOLT/issues/187

(cherry picked from FBD30796979)
2021-09-07 16:58:19 -07:00
Rafael Auler 3652483c8e [BOLTCore] [NFC] Fix braces usages according to LLVM
Summary:
Fix according to Coding Standards doc, section Don't Use
Braces on Simple Single-Statement Bodies of if/else/loop Statements.
This set of changes applies to lib Core only.

(cherry picked from FBD33240028)
2021-12-20 11:07:46 -08:00
Maksim Panchenko 2f09f445b2 [BOLT][NFC] Fix file-description comments
Summary: Fix comments at the start of source files.

(cherry picked from FBD33274597)
2021-12-21 10:21:41 -08:00
Maksim Panchenko 40c2e0fafe [BOLT][NFC] Reformat with clang-format
Summary: Selectively apply clang-format to BOLT code base.

(cherry picked from FBD33119052)
2021-12-14 16:52:51 -08:00
Maksim Panchenko ebe51c4d23 [BOLT] Use more ADT data structures for BinaryFunction
Summary:
Switched members of BinaryFunction to ADT where it was possible and
made sense. As a result, the size of BinaryFunction on x86-64 Linux
reduced from 1624 bytes to 1448.

(cherry picked from FBD32981555)
2021-12-08 22:59:09 -08:00
Rafael Auler ae585be11c [BOLT] Fix Windows build
Summary:
Make BOLT build in VisualStudio compiler and run without
crashing on a simple test. Other tests are not running.

(cherry picked from FBD32378736)
2021-11-11 18:14:53 -08:00
Rafael Auler a34c753fe7 Rebase: [NFC] Refactor sources to be buildable in shared mode
Summary:
Moves source files into separate components, and make explicit
component dependency on each other, so LLVM build system knows how to
build BOLT in BUILD_SHARED_LIBS=ON.

Please use the -c merge.renamelimit=230 git option when rebasing your
work on top of this change.

To achieve this, we create a new library to hold core IR files (most
classes beginning with Binary in their names), a new library to hold
Utils, some command line options shared across both RewriteInstance
and core IR files, a new library called Rewrite to hold most classes
concerned with running top-level functions coordinating the binary
rewriting process, and a new library called Profile to hold classes
dealing with profile reading and writing.

To remove the dependency from BinaryContext into X86-specific classes,
we do some refactoring on the BinaryContext constructor to receive a
reference to the specific backend directly from RewriteInstance. Then,
the dependency on X86 or AArch64-specific classes is transfered to the
Rewrite library. We can't have the Core library depend on targets
because targets depend on Core (which would create a cycle).

Files implementing the entry point of a tool are transferred to the
tools/ folder. All header files are transferred to the include/
folder. The src/ folder was renamed to lib/.

(cherry picked from FBD32746834)
2021-10-08 11:47:10 -07:00