[PATCH] D15000: [ELF] - Implemented @tlsgd optimization (GD->IE case, x64).

[Rui Ueyama via llvm-commits]

ruiu added inline comments.

================
Comment at: ELF/OutputSections.cpp:221-226
@@ -220,2 +220,8 @@
   if (Body && Target->isTlsGlobalDynamicReloc(Type)) {
+    if (Target->isTlsOptimized(Type, Body)) {
+      P->setSymbolAndType(Body->getDynamicSymbolTableIndex(),
+                          Target->getTlsGotReloc(), Config->Mips64EL);
+      P->r_offset = Out<ELFT>::Got->getEntryAddr(*Body);
+      return true;
+    }
     P->setSymbolAndType(Body->getDynamicSymbolTableIndex(),
----------------
Can you reduce the nest level by moving this `if` outside of the outer `if? I mean

  if (Body && Target->isTlsOptimized(Type, Body)) {
    P->setSymbolAndType(Body->getDynamicSymbolTableIndex(),
                        Target->getTlsGotReloc(), Config->Mips64EL);
    P->r_offset = Out<ELFT>::Got->getEntryAddr(*Body);
    return true;
  }

  if (Body && Target->isTlsGlobalDynamicReloc(Type)) {
    ...
  }

================
Comment at: ELF/Target.cpp:494-495
@@ -489,3 +493,4 @@
 
-bool X86_64TargetInfo::isTlsOptimized(unsigned Type,
-                                      const SymbolBody *S) const {
+// Returns optimization level. 0 - not optimized,
+// 1 - partial, other values - full.
+uint32_t X86_64TargetInfo::isTlsOptimized(unsigned Type,
----------------
I don't think these magic numbers are good. In fact it seems that you don't need them. Please see the comment below.

================
Comment at: ELF/Target.cpp:624
@@ +623,3 @@
+  case R_X86_64_TLSGD: {
+    if (isTlsOptimized(Type, &S) == 1)
+      relocateTlsGdToIe(Loc, BufEnd, P, SA);
----------------
This can be

  if (canBePreempted(&S, true))


http://reviews.llvm.org/D15000