[PATCH] D158708: [JITLink][PowerPC] Fix incorrect assertion of addend for R_PPC64_REL24

[Kai Luo via Phabricator via llvm-commits]

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There is case that R_PPC64_REL24 with non-zero addend. The assertion is incorrectly triggered in such situation.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D158708

Files:
  llvm/include/llvm/ExecutionEngine/JITLink/ppc64.h
  llvm/lib/ExecutionEngine/JITLink/ELF_ppc64.cpp


Index: llvm/lib/ExecutionEngine/JITLink/ELF_ppc64.cpp
===================================================================
--- llvm/lib/ExecutionEngine/JITLink/ELF_ppc64.cpp
+++ llvm/lib/ExecutionEngine/JITLink/ELF_ppc64.cpp
@@ -346,9 +346,13 @@
       break;
     case ELF::R_PPC64_REL24:
       Kind = ppc64::RequestCall;
-      assert(Addend == 0 && "Addend is expected to be 0 for a function call");
-      // We assume branching to local entry, will reverse the addend if not.
-      Addend = ELF::decodePPC64LocalEntryOffset((*ObjSymbol)->st_other);
+      // Determining a target is external or not is deferred in PostPrunePass.
+      // We assume branching to local entry by default, since in PostPrunePass,
+      // we don't have any context to determine LocalEntryOffset. If it finally
+      // turns out to be an external call, we'll have a stub for the external
+      // target, the target of this edge will be the stub and its addend will be
+      // set 0.
+      Addend += ELF::decodePPC64LocalEntryOffset((*ObjSymbol)->st_other);
       break;
     case ELF::R_PPC64_REL64:
       Kind = ppc64::Delta64;
Index: llvm/include/llvm/ExecutionEngine/JITLink/ppc64.h
===================================================================
--- llvm/include/llvm/ExecutionEngine/JITLink/ppc64.h
+++ llvm/include/llvm/ExecutionEngine/JITLink/ppc64.h
@@ -205,8 +205,6 @@
         E.setKind(ppc64::CallBranchDeltaRestoreTOC);
         this->StubKind = LongBranchSaveR2;
         E.setTarget(this->getEntryForTarget(G, E.getTarget()));
-        // We previously set branching to local entry. Now reverse that
-        // operation.
         E.setAddend(0);
       } else
         // TODO: There are cases a local function call need a call stub.


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