commit edafba200f8da2b67a41bfec3d104a2e02bec0e0
author Rui Ueyama <ruiu@google.com> Fri Oct 06 23:06:40 2017 +0000
committer Rui Ueyama <ruiu@google.com> Fri Oct 06 23:06:40 2017 +0000
tree 347ea845d7e787ab3fc1559c0727ed3e32cb8e84
parent ba0f4339a7ff25ee513c8ee6a9d4713463c4c21c

Split addSection into two small functions. NFCI.

addSection function was hard to read because it behaves differently
depending on its arguments but what exactly it does is not clear.
Now it should be better. Still, it is not clear (not what but) why
it does what it does, but I'll take a look at it later.

llvm-svn: 315124

lld/ELF/LinkerScript.cpp

diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index 1bbdb01..6cfbc5d 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -458,7 +458,7 @@
     });
     log(toString(S) + " is being placed in '" + Name + "'");
     if (I == End) {
-      Factory.addInputSec(S, Name);
+      Factory.addInputSec(S, Name, nullptr);
       assert(S->getOutputSection()->SectionIndex == INT_MAX);
     } else {
       OutputSection *Sec = cast<OutputSection>(*I);

lld/ELF/OutputSections.cpp

diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index 4f929cf..e3d84d2 100644
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -200,14 +200,25 @@
           IS->File->getName() + "'");
 }
 
-static OutputSection *addSection(InputSectionBase *IS, StringRef OutsecName,
-                                 OutputSection *Sec) {
-  if (Sec && Sec->Live) {
+static OutputSection *createSection(InputSectionBase *IS, StringRef OutsecName) {
+  OutputSection *Sec = Script->createOutputSection(OutsecName, "<internal>");
+  Sec->Type = IS->Type;
+  Sec->Flags = IS->Flags;
+  Sec->addSection(cast<InputSection>(IS));
+
+  Script->Opt.Commands.push_back(Sec);
+
+  return Sec;
+}
+
+static void addSection(OutputSection *Sec, InputSectionBase *IS, StringRef OutsecName) {
+  if (Sec->Live) {
     if (getIncompatibleFlags(Sec->Flags) != getIncompatibleFlags(IS->Flags))
       error("incompatible section flags for " + Sec->Name + "\n>>> " +
             toString(IS) + ": 0x" + utohexstr(IS->Flags) +
             "\n>>> output section " + Sec->Name + ": 0x" +
             utohexstr(Sec->Flags));
+
     if (Sec->Type != IS->Type) {
       if (canMergeToProgbits(Sec->Type) && canMergeToProgbits(IS->Type))
         Sec->Type = SHT_PROGBITS;
@@ -218,18 +229,12 @@
               "\n>>> output section " + Sec->Name + ": " +
               getELFSectionTypeName(Config->EMachine, Sec->Type));
     }
-    Sec->Flags |= IS->Flags;
   } else {
-    if (!Sec) {
-      Sec = Script->createOutputSection(OutsecName, "<internal>");
-      Script->Opt.Commands.push_back(Sec);
-    }
     Sec->Type = IS->Type;
-    Sec->Flags = IS->Flags;
   }
 
+  Sec->Flags |= IS->Flags;
   Sec->addSection(cast<InputSection>(IS));
-  return Sec;
 }
 
 void OutputSectionFactory::addInputSec(InputSectionBase *IS,
@@ -242,7 +247,7 @@
 
   // If we have destination output section - use it directly.
   if (OS) {
-    addSection(IS, OutsecName, OS);
+    addSection(OS, IS, OutsecName);
     return;
   }
 
@@ -254,7 +259,7 @@
   // as-is because adding/removing members or merging them with other groups
   // change their semantics.
   if (IS->Type == SHT_GROUP || (IS->Flags & SHF_GROUP)) {
-    addSection(IS, OutsecName, nullptr);
+    createSection(IS, OutsecName);
     return;
   }
 
@@ -268,13 +273,20 @@
       (IS->Type == SHT_REL || IS->Type == SHT_RELA)) {
     auto *Sec = cast<InputSection>(IS);
     OutputSection *Out = Sec->getRelocatedSection()->getOutputSection();
-    Out->RelocationSection = addSection(IS, OutsecName, Out->RelocationSection);
+
+    if (Out->RelocationSection)
+      addSection(Out->RelocationSection, IS, OutsecName);
+    else
+      Out->RelocationSection = createSection(IS, OutsecName);
     return;
   }
 
   SectionKey Key = createKey(IS, OutsecName);
   OutputSection *&Sec = Map[Key];
-  Sec = addSection(IS, OutsecName, Sec);
+  if (Sec)
+    addSection(Sec, IS, OutsecName);
+  else
+    Sec = createSection(IS, OutsecName);
 }
 
 OutputSectionFactory::~OutputSectionFactory() {}

lld/ELF/OutputSections.h

diff --git a/lld/ELF/OutputSections.h b/lld/ELF/OutputSections.h
index dbe6c16..ef6b98a 100644
--- a/lld/ELF/OutputSections.h
+++ b/lld/ELF/OutputSections.h
@@ -165,7 +165,7 @@
   ~OutputSectionFactory();
 
   void addInputSec(InputSectionBase *IS, StringRef OutsecName,
-                   OutputSection *OS = nullptr);
+                   OutputSection *OS);
 
 private:
   llvm::SmallDenseMap<SectionKey, OutputSection *> Map;

lld/ELF/Writer.cpp

diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index 1d84710..34dfeb7 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -880,7 +880,7 @@
   Script->Opt.Commands.clear();
   for (InputSectionBase *IS : InputSections)
     if (IS)
-      Factory.addInputSec(IS, getOutputSectionName(IS->Name));
+      Factory.addInputSec(IS, getOutputSectionName(IS->Name), nullptr);
   Script->Opt.Commands.insert(Script->Opt.Commands.end(), Old.begin(),
                               Old.end());