[PATCH] D50632: [LLD][ELF] - Simplify TLS LD handling code.

[George Rimar via Phabricator via llvm-commits]

grimar created this revision.
grimar added reviewers: ruiu, syzaara.
Herald added subscribers: kbarton, arichardson, nemanjai, emaste.
Herald added a reviewer: espindola.

Our code in `handleTlsRelocation` is hard to read.
It is possible to rewrite it and reduce a bit.
That is what this patch does. It should be NFC.


https://reviews.llvm.org/D50632

Files:
  ELF/Arch/PPC64.cpp
  ELF/Relocations.cpp


Index: ELF/Relocations.cpp
===================================================================
--- ELF/Relocations.cpp
+++ ELF/Relocations.cpp
@@ -186,44 +186,33 @@
   }
 
   if (isRelExprOneOf<R_TLSLD_GOT, R_TLSLD_GOT_FROM_END, R_TLSLD_PC,
-                     R_TLSLD_HINT>(Expr)) {
-    // Local-Dynamic relocs can be relaxed to Local-Exec.
+                     R_TLSLD_HINT, R_TLSLD_GOT_OFF, R_ABS>(Expr)) {
     if (!Config->Shared) {
+      // Local-Dynamic relocs can be relaxed to Local-Exec.
       C.Relocations.push_back(
           {Target->adjustRelaxExpr(Type, nullptr, R_RELAX_TLS_LD_TO_LE), Type,
            Offset, Addend, &Sym});
-      return Target->TlsGdRelaxSkip;
+      return Expr == R_ABS ? 1 : Target->TlsGdRelaxSkip;
     }
+
+    if (Expr == R_ABS)
+      return 0;
     if (Expr == R_TLSLD_HINT)
       return 1;
-    if (InX::Got->addTlsIndex())
-      InX::RelaDyn->addReloc(Target->TlsModuleIndexRel, InX::Got,
-                             InX::Got->getTlsIndexOff(), nullptr);
-    C.Relocations.push_back({Expr, Type, Offset, Addend, &Sym});
-    return 1;
-  }
-
-  // Local-Dynamic relocs can be relaxed to Local-Exec.
-  if (Expr == R_ABS && !Config->Shared) {
-    C.Relocations.push_back(
-        {Target->adjustRelaxExpr(Type, nullptr, R_RELAX_TLS_LD_TO_LE), Type,
-         Offset, Addend, &Sym});
-    return 1;
-  }
 
-  // Local-Dynamic sequence where offset of tls variable relative to dynamic
-  // thread pointer is stored in the got.
-  if (Expr == R_TLSLD_GOT_OFF) {
-    // Local-Dynamic relocs can be relaxed to local-exec
-    if (!Config->Shared) {
-      C.Relocations.push_back({R_RELAX_TLS_LD_TO_LE, Type, Offset, Addend, &Sym});
+    if (Expr == R_TLSLD_GOT_OFF) {
+      if (!Sym.isInGot()) {
+        InX::Got->addEntry(Sym);
+        InX::Got->Relocations.push_back(
+            {R_ABS, Target->TlsOffsetRel, Sym.getGotOffset(), 0, &Sym});
+      }
+      C.Relocations.push_back({Expr, Type, Offset, Addend, &Sym});
       return 1;
     }
-    if (!Sym.isInGot()) {
-      InX::Got->addEntry(Sym);
-      uint64_t Off = Sym.getGotOffset();
-      InX::Got->Relocations.push_back({R_ABS, Target->TlsOffsetRel, Off, 0, &Sym});
-    }
+
+    if (InX::Got->addTlsIndex())
+      InX::RelaDyn->addReloc(Target->TlsModuleIndexRel, InX::Got,
+                             InX::Got->getTlsIndexOff(), nullptr);
     C.Relocations.push_back({Expr, Type, Offset, Addend, &Sym});
     return 1;
   }
Index: ELF/Arch/PPC64.cpp
===================================================================
--- ELF/Arch/PPC64.cpp
+++ ELF/Arch/PPC64.cpp
@@ -479,8 +479,13 @@
                                RelExpr Expr) const {
   if (Expr == R_RELAX_TLS_GD_TO_IE)
     return R_RELAX_TLS_GD_TO_IE_GOT_OFF;
-  if (Expr == R_RELAX_TLS_LD_TO_LE)
+
+  if (Expr == R_RELAX_TLS_LD_TO_LE) {
+    if (Type == R_PPC64_GOT_DTPREL16_HA || Type == R_PPC64_GOT_DTPREL16_LO_DS ||
+        Type == R_PPC64_GOT_DTPREL16_DS || Type == R_PPC64_GOT_DTPREL16_HI)
+      return Expr;
     return R_RELAX_TLS_LD_TO_LE_ABS;
+  }
   return Expr;
 }
 


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