[lld] r315422 - Split decompressAndMergeSection into two separate functions.

[Rui Ueyama via llvm-commits]

Author: ruiu
Date: Tue Oct 10 20:12:53 2017
New Revision: 315422

URL: http://llvm.org/viewvc/llvm-project?rev=315422&view=rev
Log:
Split decompressAndMergeSection into two separate functions.

Even though they are called sequentially, they are separate
operations, so it is better to split it.

Modified:
    lld/trunk/ELF/Driver.cpp
    lld/trunk/ELF/InputSection.cpp
    lld/trunk/ELF/SyntheticSections.cpp
    lld/trunk/ELF/SyntheticSections.h

Modified: lld/trunk/ELF/Driver.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Driver.cpp?rev=315422&r1=315421&r2=315422&view=diff
==============================================================================
--- lld/trunk/ELF/Driver.cpp (original)
+++ lld/trunk/ELF/Driver.cpp Tue Oct 10 20:12:53 2017
@@ -1107,7 +1107,8 @@ template <class ELFT> void LinkerDriver:
   // Do size optimizations: garbage collection, merging of SHF_MERGE sections
   // and identical code folding.
   markLive<ELFT>();
-  decompressAndMergeSections();
+  decompressSections();
+  mergeSections();
   if (Config->ICF)
     doIcf<ELFT>();
 

Modified: lld/trunk/ELF/InputSection.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputSection.cpp?rev=315422&r1=315421&r2=315422&view=diff
==============================================================================
--- lld/trunk/ELF/InputSection.cpp (original)
+++ lld/trunk/ELF/InputSection.cpp Tue Oct 10 20:12:53 2017
@@ -196,10 +196,7 @@ OutputSection *SectionBase::getOutputSec
 // Uncompress section contents if required. Note that this function
 // is called from parallelForEach, so it must be thread-safe.
 void InputSectionBase::maybeUncompress() {
-  if (UncompressBuf)
-    return;
-
-  if (!Decompressor::isCompressedELFSection(Flags, Name))
+  if (UncompressBuf || !Decompressor::isCompressedELFSection(Flags, Name))
     return;
 
   Decompressor Dec = check(Decompressor::create(Name, toStringRef(Data),

Modified: lld/trunk/ELF/SyntheticSections.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SyntheticSections.cpp?rev=315422&r1=315421&r2=315422&view=diff
==============================================================================
--- lld/trunk/ELF/SyntheticSections.cpp (original)
+++ lld/trunk/ELF/SyntheticSections.cpp Tue Oct 10 20:12:53 2017
@@ -2305,21 +2305,28 @@ static MergeSyntheticSection *createMerg
   return make<MergeNoTailSection>(Name, Type, Flags, Alignment);
 }
 
-// This function decompresses compressed sections and scans over the input
-// sections to create mergeable synthetic sections. It removes
-// MergeInputSections from the input section array and adds new synthetic
-// sections at the location of the first input section that it replaces. It then
-// finalizes each synthetic section in order to compute an output offset for
-// each piece of each input section.
-void elf::decompressAndMergeSections() {
-  // splitIntoPieces needs to be called on each MergeInputSection before calling
-  // finalizeContents(). Do that first.
-  parallelForEach(InputSections, [](InputSectionBase *S) {
-    if (!S->Live)
-      return;
-    S->maybeUncompress();
-    if (auto *MS = dyn_cast<MergeInputSection>(S))
-      MS->splitIntoPieces();
+// Debug sections may be compressed by zlib. Uncompress if exists.
+void elf::decompressSections() {
+  parallelForEach(InputSections, [](InputSectionBase *Sec) {
+    if (Sec->Live)
+      Sec->maybeUncompress();
+  });
+}
+
+// This function scans over the inputsections to create mergeable
+// synthetic sections.
+//
+// It removes MergeInputSections from the input section array and adds
+// new synthetic sections at the location of the first input section
+// that it replaces. It then finalizes each synthetic section in order
+// to compute an output offset for each piece of each input section.
+void elf::mergeSections() {
+  // splitIntoPieces needs to be called on each MergeInputSection
+  // before calling finalizeContents(). Do that first.
+  parallelForEach(InputSections, [](InputSectionBase *Sec) {
+    if (Sec->Live)
+      if (auto *S = dyn_cast<MergeInputSection>(Sec))
+        S->splitIntoPieces();
   });
 
   std::vector<MergeSyntheticSection *> MergeSections;

Modified: lld/trunk/ELF/SyntheticSections.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SyntheticSections.h?rev=315422&r1=315421&r2=315422&view=diff
==============================================================================
--- lld/trunk/ELF/SyntheticSections.h (original)
+++ lld/trunk/ELF/SyntheticSections.h Tue Oct 10 20:12:53 2017
@@ -805,7 +805,8 @@ private:
 template <class ELFT> void createCommonSections();
 InputSection *createInterpSection();
 template <class ELFT> MergeInputSection *createCommentSection();
-void decompressAndMergeSections();
+void decompressSections();
+void mergeSections();
 
 SymbolBody *addSyntheticLocal(StringRef Name, uint8_t Type, uint64_t Value,
                               uint64_t Size, InputSectionBase *Section);