[BOLT] More refactoring of PHDR handling. NFC

[maksfb]

Replace ad-hoc adjustment of the program header count with info from the new segment list.

[llvmbot]

@llvm/pr-subscribers-bolt

Author: Maksim Panchenko (maksfb)

Changes

Replace ad-hoc adjustment of the program header count with info from the new segment list.

---

Full diff: https://github.com/llvm/llvm-project/pull/148932.diff

1 Files Affected:

• (modified) bolt/lib/Rewrite/RewriteInstance.cpp (+12-18)

diff --git a/bolt/lib/Rewrite/RewriteInstance.cpp b/bolt/lib/Rewrite/RewriteInstance.cpp index 96045a916232c..f1b94e4a821a6 100644 --- a/bolt/lib/Rewrite/RewriteInstance.cpp +++ b/bolt/lib/Rewrite/RewriteInstance.cpp @@ -4260,31 +4260,25 @@ void RewriteInstance::patchELFPHDRTable() { const ELFFile<ELF64LE> &Obj = ELF64LEFile->getELFFile(); raw_fd_ostream &OS = Out->os(); - // Write/re-write program headers. Phnum = Obj.getHeader().e_phnum; - if (PHDRTableOffset) { - // Writing new pheader table and adding one new entry for R+X segment. - Phnum += 1; - if (NewWritableSegmentSize) { - // Adding one more entry for R+W segment. - Phnum += 1; - } - } else { + + if (BC->NewSegments.empty()) { + BC->outs() << "BOLT-INFO: not adding new segments\n"; + return; + } + + if (opts::UseGnuStack) { assert(!PHDRTableAddress && "unexpected address for program header table"); - PHDRTableOffset = Obj.getHeader().e_phoff; - if (NewWritableSegmentSize) { + if (BC->NewSegments.size() > 1) { BC->errs() << "BOLT-ERROR: unable to add writable segment\n"; exit(1); } + } else { + Phnum += BC->NewSegments.size(); } - if (opts::Instrument) - Phnum += 2; - - if (BC->NewSegments.empty()) { - BC->outs() << "BOLT-INFO: not adding new segments\n"; - return; - } + if (!PHDRTableOffset) + PHDRTableOffset = Obj.getHeader().e_phoff; const uint64_t SavedPos = OS.tell(); OS.seek(PHDRTableOffset);