[lld] r248099 - COFF: Move markLive() from Writer.cpp to its own file.
Rui Ueyama via llvm-commits
llvm-commits at lists.llvm.org
Sat Sep 19 14:36:28 PDT 2015
Author: ruiu
Date: Sat Sep 19 16:36:28 2015
New Revision: 248099
URL: http://llvm.org/viewvc/llvm-project?rev=248099&view=rev
Log:
COFF: Move markLive() from Writer.cpp to its own file.
Conceptually, garbage collection is not part of Writer,
so move the function out of the file.
Added:
lld/trunk/COFF/MarkLive.cpp
Modified:
lld/trunk/COFF/CMakeLists.txt
lld/trunk/COFF/Driver.cpp
lld/trunk/COFF/Driver.h
lld/trunk/COFF/Writer.cpp
lld/trunk/COFF/Writer.h
Modified: lld/trunk/COFF/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/CMakeLists.txt?rev=248099&r1=248098&r2=248099&view=diff
==============================================================================
--- lld/trunk/COFF/CMakeLists.txt (original)
+++ lld/trunk/COFF/CMakeLists.txt Sat Sep 19 16:36:28 2015
@@ -10,6 +10,7 @@ add_llvm_library(lldCOFF
Error.cpp
ICF.cpp
InputFiles.cpp
+ MarkLive.cpp
ModuleDef.cpp
SymbolTable.cpp
Symbols.cpp
Modified: lld/trunk/COFF/Driver.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/Driver.cpp?rev=248099&r1=248098&r2=248099&view=diff
==============================================================================
--- lld/trunk/COFF/Driver.cpp (original)
+++ lld/trunk/COFF/Driver.cpp Sat Sep 19 16:36:28 2015
@@ -644,6 +644,14 @@ void LinkerDriver::link(llvm::ArrayRef<c
if (auto *Arg = Args.getLastArg(OPT_pdb))
touchFile(Arg->getValue());
+ // Identify unreferenced COMDAT sections.
+ if (Config->DoGC)
+ markLive(Symtab.getChunks());
+
+ // Identify identical COMDAT sections to merge them.
+ if (Config->DoICF)
+ doICF(Symtab.getChunks());
+
// Write the result.
writeResult(&Symtab);
Modified: lld/trunk/COFF/Driver.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/Driver.h?rev=248099&r1=248098&r2=248099&view=diff
==============================================================================
--- lld/trunk/COFF/Driver.h (original)
+++ lld/trunk/COFF/Driver.h Sat Sep 19 16:36:28 2015
@@ -37,6 +37,12 @@ class InputFile;
// Entry point of the COFF linker.
void link(llvm::ArrayRef<const char *> Args);
+// Implemented in MarkLive.cpp.
+void markLive(const std::vector<Chunk *> &Chunks);
+
+// Implemented in ICF.cpp.
+void doICF(const std::vector<Chunk *> &Chunks);
+
class ArgParser {
public:
ArgParser() : Alloc(AllocAux) {}
Added: lld/trunk/COFF/MarkLive.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/MarkLive.cpp?rev=248099&view=auto
==============================================================================
--- lld/trunk/COFF/MarkLive.cpp (added)
+++ lld/trunk/COFF/MarkLive.cpp Sat Sep 19 16:36:28 2015
@@ -0,0 +1,61 @@
+//===- MarkLive.cpp -------------------------------------------------------===//
+//
+// The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Chunks.h"
+#include "Symbols.h"
+#include "llvm/ADT/STLExtras.h"
+#include <vector>
+
+namespace lld {
+namespace coff {
+
+// Set live bit on for each reachable chunk. Unmarked (unreachable)
+// COMDAT chunks will be ignored by Writer, so they will be excluded
+// from the final output.
+void markLive(const std::vector<Chunk *> &Chunks) {
+ // We build up a worklist of sections which have been marked as live. We only
+ // push into the worklist when we discover an unmarked section, and we mark
+ // as we push, so sections never appear twice in the list.
+ SmallVector<SectionChunk *, 256> Worklist;
+
+ // COMDAT section chunks are dead by default. Add non-COMDAT chunks.
+ for (Chunk *C : Chunks)
+ if (auto *SC = dyn_cast<SectionChunk>(C))
+ if (SC->isLive())
+ Worklist.push_back(SC);
+
+ auto Enqueue = [&](SectionChunk *C) {
+ if (C->isLive())
+ return;
+ C->markLive();
+ Worklist.push_back(C);
+ };
+
+ // Add GC root chunks.
+ for (Undefined *U : Config->GCRoot)
+ if (auto *D = dyn_cast<DefinedRegular>(U->repl()))
+ Enqueue(D->getChunk());
+
+ while (!Worklist.empty()) {
+ SectionChunk *SC = Worklist.pop_back_val();
+ assert(SC->isLive() && "We mark as live when pushing onto the worklist!");
+
+ // Mark all symbols listed in the relocation table for this section.
+ for (SymbolBody *S : SC->symbols())
+ if (auto *D = dyn_cast<DefinedRegular>(S->repl()))
+ Enqueue(D->getChunk());
+
+ // Mark associative sections if any.
+ for (SectionChunk *C : SC->children())
+ Enqueue(C);
+ }
+}
+
+}
+}
Modified: lld/trunk/COFF/Writer.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/Writer.cpp?rev=248099&r1=248098&r2=248099&view=diff
==============================================================================
--- lld/trunk/COFF/Writer.cpp (original)
+++ lld/trunk/COFF/Writer.cpp Sat Sep 19 16:36:28 2015
@@ -49,8 +49,6 @@ public:
void run();
private:
- void markLive();
- void dedupCOMDATs();
void createSections();
void createMiscChunks();
void createImportTables();
@@ -216,8 +214,6 @@ bool Defined::isExecutable() {
// The main function of the writer.
void Writer::run() {
- markLive();
- dedupCOMDATs();
createSections();
createMiscChunks();
createImportTables();
@@ -239,57 +235,6 @@ void Writer::run() {
error(Buffer->commit(), "Failed to write the output file");
}
-// Set live bit on for each reachable chunk. Unmarked (unreachable)
-// COMDAT chunks will be ignored in the next step, so that they don't
-// come to the final output file.
-void Writer::markLive() {
- if (!Config->DoGC)
- return;
-
- // We build up a worklist of sections which have been marked as live. We only
- // push into the worklist when we discover an unmarked section, and we mark
- // as we push, so sections never appear twice in the list.
- SmallVector<SectionChunk *, 256> Worklist;
-
- // COMDAT section chunks are dead by default. Add non-COMDAT chunks.
- for (Chunk *C : Symtab->getChunks())
- if (auto *SC = dyn_cast<SectionChunk>(C))
- if (SC->isLive())
- Worklist.push_back(SC);
-
- auto Enqueue = [&](SectionChunk *C) {
- if (C->isLive())
- return;
- C->markLive();
- Worklist.push_back(C);
- };
-
- // Add GC root chunks.
- for (Undefined *U : Config->GCRoot)
- if (auto *D = dyn_cast<DefinedRegular>(U->repl()))
- Enqueue(D->getChunk());
-
- while (!Worklist.empty()) {
- SectionChunk *SC = Worklist.pop_back_val();
- assert(SC->isLive() && "We mark as live when pushing onto the worklist!");
-
- // Mark all symbols listed in the relocation table for this section.
- for (SymbolBody *S : SC->symbols())
- if (auto *D = dyn_cast<DefinedRegular>(S->repl()))
- Enqueue(D->getChunk());
-
- // Mark associative sections if any.
- for (SectionChunk *C : SC->children())
- Enqueue(C);
- }
-}
-
-// Merge identical COMDAT sections.
-void Writer::dedupCOMDATs() {
- if (Config->DoICF)
- doICF(Symtab->getChunks());
-}
-
static StringRef getOutputSection(StringRef Name) {
StringRef S = Name.split('$').first;
auto It = Config->Merge.find(S);
Modified: lld/trunk/COFF/Writer.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/Writer.h?rev=248099&r1=248098&r2=248099&view=diff
==============================================================================
--- lld/trunk/COFF/Writer.h (original)
+++ lld/trunk/COFF/Writer.h Sat Sep 19 16:36:28 2015
@@ -20,9 +20,6 @@ class OutputSection;
void writeResult(SymbolTable *T);
-// Implemented in ICF.cpp.
-void doICF(const std::vector<Chunk *> &Chunks);
-
}
}
More information about the llvm-commits
mailing list