[PATCH] D30084: [ELF] - Move DependentSections vector from InputSection to InputSectionBase

[Rafael Avila de Espindola via llvm-commits]

LGTM. Feel free to commit in 1 or 2 patches.

George Rimar via Phabricator <reviews at reviews.llvm.org> writes:

> grimar created this revision.
>
> I splitted it from https://reviews.llvm.org/D29273.
> Since we plan to make relocatable sections as dependent for target ones for
> --emit-relocs implementation, this change is required to support .eh_frame case.
>
> EhInputSection inherets from InputSectionBase and not from InputSection.
> So for case when it has relocation section, it should be able to access DependentSections
> vector.
>
> This case is real for Linux kernel.
>
>
> https://reviews.llvm.org/D30084
>
> Files:
>   ELF/InputFiles.cpp
>   ELF/InputSection.h
>   ELF/LinkerScript.cpp
>
>
> Index: ELF/LinkerScript.cpp
> ===================================================================
> --- ELF/LinkerScript.cpp
> +++ ELF/LinkerScript.cpp
> @@ -277,11 +277,7 @@
>    for (InputSectionBase<ELFT> *S : V) {
>      S->Live = false;
>      reportDiscarded(S);
> -
> -    InputSection<ELFT> *IS = dyn_cast<InputSection<ELFT>>(S);
> -    if (!IS || IS->DependentSections.empty())
> -      continue;
> -    discard(IS->DependentSections);
> +    discard(S->DependentSections);
>    }
>  }
>  
> Index: ELF/InputSection.h
> ===================================================================
> --- ELF/InputSection.h
> +++ ELF/InputSection.h
> @@ -128,6 +128,9 @@
>    // this but instead this->Repl.
>    InputSectionBase<ELFT> *Repl;
>  
> +  // InputSections that are dependent on us (reverse dependency for GC)
> +  llvm::TinyPtrVector<InputSectionBase<ELFT> *> DependentSections;
> +
>    // Returns the size of this section (even if this is a common or BSS.)
>    size_t getSize() const;
>  
> @@ -281,9 +284,6 @@
>    // to. The writer sets a value.
>    uint64_t OutSecOff = 0;
>  
> -  // InputSections that are dependent on us (reverse dependency for GC)
> -  llvm::TinyPtrVector<InputSectionBase<ELFT> *> DependentSections;
> -
>    static bool classof(const InputSectionData *S);
>  
>    InputSectionBase<ELFT> *getRelocatedSection();
> Index: ELF/InputFiles.cpp
> ===================================================================
> --- ELF/InputFiles.cpp
> +++ ELF/InputFiles.cpp
> @@ -322,8 +322,7 @@
>        if (Sec.sh_link >= Sections.size())
>          fatal(toString(this) + ": invalid sh_link index: " +
>                Twine(Sec.sh_link));
> -      auto *IS = cast<InputSection<ELFT>>(Sections[Sec.sh_link]);
> -      IS->DependentSections.push_back(Sections[I]);
> +      Sections[Sec.sh_link]->DependentSections.push_back(Sections[I]);
>      }
>    }
>  }
>
>
> Index: ELF/LinkerScript.cpp
> ===================================================================
> --- ELF/LinkerScript.cpp
> +++ ELF/LinkerScript.cpp
> @@ -277,11 +277,7 @@
>    for (InputSectionBase<ELFT> *S : V) {
>      S->Live = false;
>      reportDiscarded(S);
> -
> -    InputSection<ELFT> *IS = dyn_cast<InputSection<ELFT>>(S);
> -    if (!IS || IS->DependentSections.empty())
> -      continue;
> -    discard(IS->DependentSections);
> +    discard(S->DependentSections);
>    }
>  }
>  
> Index: ELF/InputSection.h
> ===================================================================
> --- ELF/InputSection.h
> +++ ELF/InputSection.h
> @@ -128,6 +128,9 @@
>    // this but instead this->Repl.
>    InputSectionBase<ELFT> *Repl;
>  
> +  // InputSections that are dependent on us (reverse dependency for GC)
> +  llvm::TinyPtrVector<InputSectionBase<ELFT> *> DependentSections;
> +
>    // Returns the size of this section (even if this is a common or BSS.)
>    size_t getSize() const;
>  
> @@ -281,9 +284,6 @@
>    // to. The writer sets a value.
>    uint64_t OutSecOff = 0;
>  
> -  // InputSections that are dependent on us (reverse dependency for GC)
> -  llvm::TinyPtrVector<InputSectionBase<ELFT> *> DependentSections;
> -
>    static bool classof(const InputSectionData *S);
>  
>    InputSectionBase<ELFT> *getRelocatedSection();
> Index: ELF/InputFiles.cpp
> ===================================================================
> --- ELF/InputFiles.cpp
> +++ ELF/InputFiles.cpp
> @@ -322,8 +322,7 @@
>        if (Sec.sh_link >= Sections.size())
>          fatal(toString(this) + ": invalid sh_link index: " +
>                Twine(Sec.sh_link));
> -      auto *IS = cast<InputSection<ELFT>>(Sections[Sec.sh_link]);
> -      IS->DependentSections.push_back(Sections[I]);
> +      Sections[Sec.sh_link]->DependentSections.push_back(Sections[I]);
>      }
>    }
>  }