[PATCH] D127062: [JITLink] Remove CodeAlignmentFactor and DataAlignmentFactor validation

[Sunho Kim via Phabricator via llvm-commits]

sunho created this revision.
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This patch removes CodeAlignmentFactor and DataAlignmentFactor validation in EHFrameEdgeFixer. I observed some of  aarch64 elf files generated by clang contains CIE record with code_alignment_factor = 4 or data_alignment_factor = -8. If I'm understading correctly, code_alignment_factor and  data_alignment_factor are used by call fram instruction that should be correctled handled by libunwind. But, I also see the verification was added in the intial code base and not touched since then.


https://reviews.llvm.org/D127062

Files:
  llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp


Index: llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
===================================================================
--- llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
+++ llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
@@ -213,10 +213,6 @@
     uint64_t CodeAlignmentFactor = 0;
     if (auto Err = RecordReader.readULEB128(CodeAlignmentFactor))
       return Err;
-    if (CodeAlignmentFactor != 1)
-      return make_error<JITLinkError>("Unsupported CIE code alignment factor " +
-                                      Twine(CodeAlignmentFactor) +
-                                      " (expected 1)");
   }
 
   // Read and validate the data alignment factor.
@@ -224,10 +220,6 @@
     int64_t DataAlignmentFactor = 0;
     if (auto Err = RecordReader.readSLEB128(DataAlignmentFactor))
       return Err;
-    if (DataAlignmentFactor != -8)
-      return make_error<JITLinkError>("Unsupported CIE data alignment factor " +
-                                      Twine(DataAlignmentFactor) +
-                                      " (expected -8)");
   }
 
   // Skip the return address register field.


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