[mips][mcjit] Calculate correct addend for HI16 and PCHI16 reloc

Previously, for O32 ABI we did not calculate correct addend for R_MIPS_HI16 and R_MIPS_PCHI16 relocations. This patch fixes that. Patch by Vladimir Radosavljevic. Differential Revision: http://reviews.llvm.org/D11186 llvm-svn: 244897
llvm · Aug 13, 2015 · d22164d · d22164d
1 parent 25f5185
commit d22164d
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Showing 4 changed files with 76 additions and 11 deletions.
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
@@ -522,6 +522,9 @@ void RuntimeDyldImpl::emitCommonSymbols(const ObjectFile &Obj,
     Offset += Size;
     Addr += Size;
   }
+
+  if (Checker)
+    Checker->registerSection(Obj.getFileName(), SectionID);
 }
 
 unsigned RuntimeDyldImpl::emitSection(const ObjectFile &Obj,

diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
@@ -1123,6 +1123,29 @@ void RuntimeDyldELF::processSimpleRelocation(unsigned SectionID, uint64_t Offset
     addRelocationForSection(RE, Value.SectionID);
 }
 
+uint32_t RuntimeDyldELF::getMatchingLoRelocation(uint32_t RelType,
+                                                 bool IsLocal) const {
+  switch (RelType) {
+  case ELF::R_MICROMIPS_GOT16:
+    if (IsLocal)
+      return ELF::R_MICROMIPS_LO16;
+    break;
+  case ELF::R_MICROMIPS_HI16:
+    return ELF::R_MICROMIPS_LO16;
+  case ELF::R_MIPS_GOT16:
+    if (IsLocal)
+      return ELF::R_MIPS_LO16;
+    break;
+  case ELF::R_MIPS_HI16:
+    return ELF::R_MIPS_LO16;
+  case ELF::R_MIPS_PCHI16:
+    return ELF::R_MIPS_PCLO16;
+  default:
+    break;
+  }
+  return ELF::R_MIPS_NONE;
+}
+
 relocation_iterator RuntimeDyldELF::processRelocationRef(
     unsigned SectionID, relocation_iterator RelI, const ObjectFile &O,
     ObjSectionToIDMap &ObjSectionToID, StubMap &Stubs) {
@@ -1331,17 +1354,35 @@ relocation_iterator RuntimeDyldELF::processRelocationRef(
         addRelocationForSection(RE, SectionID);
         Section.StubOffset += getMaxStubSize();
       }
+    } else if (RelType == ELF::R_MIPS_HI16 || RelType == ELF::R_MIPS_PCHI16) {
+      int64_t Addend = (Opcode & 0x0000ffff) << 16;
+      RelocationEntry RE(SectionID, Offset, RelType, Addend);
+      PendingRelocs.push_back(std::make_pair(Value, RE));
+    } else if (RelType == ELF::R_MIPS_LO16 || RelType == ELF::R_MIPS_PCLO16) {
+      int64_t Addend = Value.Addend + SignExtend32<16>(Opcode & 0x0000ffff);
+      for (auto I = PendingRelocs.begin(); I != PendingRelocs.end();) {
+        const RelocationValueRef &MatchingValue = I->first;
+        RelocationEntry &Reloc = I->second;
+        if (MatchingValue == Value &&
+            RelType == getMatchingLoRelocation(Reloc.RelType) &&
+            SectionID == Reloc.SectionID) {
+          Reloc.Addend += Addend;
+          if (Value.SymbolName)
+            addRelocationForSymbol(Reloc, Value.SymbolName);
+          else
+            addRelocationForSection(Reloc, Value.SectionID);
+          I = PendingRelocs.erase(I);
+        } else
+          ++I;
+      }
+      RelocationEntry RE(SectionID, Offset, RelType, Addend);
+      if (Value.SymbolName)
+        addRelocationForSymbol(RE, Value.SymbolName);
+      else
+        addRelocationForSection(RE, Value.SectionID);
     } else {
-      // FIXME: Calculate correct addends for R_MIPS_HI16, R_MIPS_LO16,
-      // R_MIPS_PCHI16 and R_MIPS_PCLO16 relocations.
-      if (RelType == ELF::R_MIPS_HI16 || RelType == ELF::R_MIPS_PCHI16)
-        Value.Addend += (Opcode & 0x0000ffff) << 16;
-      else if (RelType == ELF::R_MIPS_LO16)
-        Value.Addend += (Opcode & 0x0000ffff);
-      else if (RelType == ELF::R_MIPS_32)
+      if (RelType == ELF::R_MIPS_32)
         Value.Addend += Opcode;
-      else if (RelType == ELF::R_MIPS_PCLO16)
-        Value.Addend += SignExtend32<16>((Opcode & 0x0000ffff));
       else if (RelType == ELF::R_MIPS_PC16)
         Value.Addend += SignExtend32<18>((Opcode & 0x0000ffff) << 2);
       else if (RelType == ELF::R_MIPS_PC19_S2)
@@ -1719,6 +1760,10 @@ RelocationEntry RuntimeDyldELF::computeGOTOffsetRE(unsigned SectionID, uint64_t
 
 void RuntimeDyldELF::finalizeLoad(const ObjectFile &Obj,
                                   ObjSectionToIDMap &SectionMap) {
+  if (IsMipsO32ABI)
+    if (!PendingRelocs.empty())
+      report_fatal_error("Can't find matching LO16 reloc");
+
   // If necessary, allocate the global offset table
   if (GOTSectionID != 0) {
     // Allocate memory for the section

diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
@@ -123,6 +123,10 @@ class RuntimeDyldELF : public RuntimeDyldImpl {
   // no particular advanced processing.
   void processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value);
 
+  // Return matching *LO16 relocation (Mips specific)
+  uint32_t getMatchingLoRelocation(uint32_t RelType,
+                                   bool IsLocal = false) const;
+
   // The tentative ID for the GOT section
   unsigned GOTSectionID;
 
@@ -138,6 +142,10 @@ class RuntimeDyldELF : public RuntimeDyldImpl {
   // A map to avoid duplicate got entries (Mips64 specific)
   StringMap<uint64_t> GOTSymbolOffsets;
 
+  // *HI16 relocations will be added for resolving when we find matching
+  // *LO16 part. (Mips specific)
+  SmallVector<std::pair<RelocationValueRef, RelocationEntry>, 8> PendingRelocs;
+
   // When a module is loaded we save the SectionID of the EH frame section
   // in a table until we receive a request to register all unregistered
   // EH frame sections with the memory manager.

diff --git a/llvm/test/ExecutionEngine/RuntimeDyld/Mips/ELF_O32_PIC_relocations.s b/llvm/test/ExecutionEngine/RuntimeDyld/Mips/ELF_O32_PIC_relocations.s
@@ -1,10 +1,10 @@
 # RUN: llvm-mc -triple=mipsel-unknown-linux -relocation-model=pic -code-model=small -filetype=obj -o %T/test_ELF_O32.o %s
 # RUN: llc -mtriple=mipsel-unknown-linux -relocation-model=pic -filetype=obj -o %T/test_ELF_ExternalFunction_O32.o %S/Inputs/ExternalFunction.ll
-# RUN: llvm-rtdyld -triple=mipsel-unknown-linux -verify -map-section test_ELF_O32.o,.text=0x1000 -map-section test_ELF_ExternalFunction_O32.o,.text=0x10000 -check=%s %T/test_ELF_O32.o %T/test_ELF_ExternalFunction_O32.o
+# RUN: llvm-rtdyld -triple=mipsel-unknown-linux -verify -map-section test_ELF_O32.o,"<common symbols>"=0x7FF8 -map-section test_ELF_O32.o,.text=0x1000 -map-section test_ELF_ExternalFunction_O32.o,.text=0x10000 -check=%s %T/test_ELF_O32.o %T/test_ELF_ExternalFunction_O32.o
 
 # RUN: llvm-mc -triple=mips-unknown-linux -relocation-model=pic -code-model=small -filetype=obj -o %T/test_ELF_O32.o %s
 # RUN: llc -mtriple=mips-unknown-linux -relocation-model=pic -filetype=obj -o %/T/test_ELF_ExternalFunction_O32.o %S/Inputs/ExternalFunction.ll
-# RUN: llvm-rtdyld -triple=mips-unknown-linux -verify -map-section test_ELF_O32.o,.text=0x1000 -map-section test_ELF_ExternalFunction_O32.o,.text=0x10000 -check=%s %T/test_ELF_O32.o %T/test_ELF_ExternalFunction_O32.o
+# RUN: llvm-rtdyld -triple=mips-unknown-linux -verify -map-section test_ELF_O32.o,"<common symbols>"=0x7FF8 -map-section test_ELF_O32.o,.text=0x1000 -map-section test_ELF_ExternalFunction_O32.o,.text=0x10000 -check=%s %T/test_ELF_O32.o %T/test_ELF_ExternalFunction_O32.o
 
         .data
 # rtdyld-check: *{4}R_MIPS_32 = foo[31:0]
@@ -52,4 +52,13 @@ R_MIPS_HI16:
 R_MIPS_LO16:
 	lui	$1, %lo(foo)
 
+# rtdyld-check:  decode_operand(R_MIPS_HI16_ADDEND, 1)[15:0] = (var+0x8008)[31:16]
+R_MIPS_HI16_ADDEND:
+	lui	$2, %hi(var+8)
+
+# rtdyld-check:  decode_operand(R_MIPS_LO16_ADDEND, 2)[15:0] = (var+0x8)[15:0]
+R_MIPS_LO16_ADDEND:
+	lb	$2, %lo(var+8)($2)
+
 	.size	bar, .-bar
+	.comm	var,9,1