[llvm] 14cb8c5 - [lldb] add required for lldb RISCV relocations in MCJIT (#126266)

[via llvm-commits]

Author: dlav-sc
Date: 2025-04-14T15:15:33+03:00
New Revision: 14cb8c56b26784c684865053a6deb066f9a5e5b5

URL: https://github.com/llvm/llvm-project/commit/14cb8c56b26784c684865053a6deb066f9a5e5b5
DIFF: https://github.com/llvm/llvm-project/commit/14cb8c56b26784c684865053a6deb066f9a5e5b5.diff

LOG: [lldb] add required for lldb RISCV relocations in MCJIT (#126266)

After implementing CFI instructions in the function prologue, LLDB
testing for RISC-V started failing due to insufficient relocations
(e.g., R_RISCV_SET8, R_RISCV_SET16).

This patch adds support for the necessary RISC-V relocations in MCJIT.

Added: 
    

Modified: 
    llvm/include/llvm/Support/Endian.h
    llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/Support/Endian.h b/llvm/include/llvm/Support/Endian.h
index f86ea8901ae46..574f9508420a0 100644
--- a/llvm/include/llvm/Support/Endian.h
+++ b/llvm/include/llvm/Support/Endian.h
@@ -277,6 +277,9 @@ struct packed_endian_specific_integral {
 
 } // end namespace detail
 
+using ulittle8_t =
+    detail::packed_endian_specific_integral<uint8_t, llvm::endianness::little,
+                                            unaligned>;
 using ulittle16_t =
     detail::packed_endian_specific_integral<uint16_t, llvm::endianness::little,
                                             unaligned>;

diff  --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
index def117448ab6a..f032d5cb30f23 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
@@ -1306,6 +1306,11 @@ void RuntimeDyldELF::resolveRISCVRelocation(const SectionEntry &Section,
     Ref = Value + Addend;
     break;
   }
+  case ELF::R_RISCV_ADD8: {
+    auto Ref = support::ulittle8_t::ref(Section.getAddressWithOffset(Offset));
+    Ref = Ref + Value + Addend;
+    break;
+  }
   case ELF::R_RISCV_ADD16: {
     auto Ref = support::ulittle16_t::ref(Section.getAddressWithOffset(Offset));
     Ref = Ref + Value + Addend;
@@ -1321,6 +1326,11 @@ void RuntimeDyldELF::resolveRISCVRelocation(const SectionEntry &Section,
     Ref = Ref + Value + Addend;
     break;
   }
+  case ELF::R_RISCV_SUB8: {
+    auto Ref = support::ulittle8_t::ref(Section.getAddressWithOffset(Offset));
+    Ref = Ref - Value - Addend;
+    break;
+  }
   case ELF::R_RISCV_SUB16: {
     auto Ref = support::ulittle16_t::ref(Section.getAddressWithOffset(Offset));
     Ref = Ref - Value - Addend;
@@ -1336,6 +1346,21 @@ void RuntimeDyldELF::resolveRISCVRelocation(const SectionEntry &Section,
     Ref = Ref - Value - Addend;
     break;
   }
+  case ELF::R_RISCV_SET8: {
+    auto Ref = support::ulittle8_t::ref(Section.getAddressWithOffset(Offset));
+    Ref = Value + Addend;
+    break;
+  }
+  case ELF::R_RISCV_SET16: {
+    auto Ref = support::ulittle16_t::ref(Section.getAddressWithOffset(Offset));
+    Ref = Value + Addend;
+    break;
+  }
+  case ELF::R_RISCV_SET32: {
+    auto Ref = support::ulittle32_t::ref(Section.getAddressWithOffset(Offset));
+    Ref = Value + Addend;
+    break;
+  }
   }
 }