Vendor import of llvm trunk r130700:

http://llvm.org/svn/llvm-project/llvm/trunk@130700

1 files changed, 19 insertions, 9 deletions

diff --git a/lib/MC/WinCOFFObjectWriter.cpp b/lib/MC/WinCOFFObjectWriter.cpp
index 6ca5d37..101237a 100644
--- a/lib/MC/WinCOFFObjectWriter.cpp
+++ b/lib/MC/WinCOFFObjectWriter.cpp
@@ -647,22 +647,27 @@ void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm,
 
   COFFSection *coff_section = SectionMap[&SectionData->getSection()];
   COFFSymbol *coff_symbol = SymbolMap[&A_SD.getSymbol()];
+  const MCSymbolRefExpr *SymA = Target.getSymA();
+  const MCSymbolRefExpr *SymB = Target.getSymB();
+  const bool CrossSection = SymB &&
+    &SymA->getSymbol().getSection() != &SymB->getSymbol().getSection();
 
   if (Target.getSymB()) {
-    if (&Target.getSymA()->getSymbol().getSection()
-     != &Target.getSymB()->getSymbol().getSection()) {
-      llvm_unreachable("Symbol relative relocations are only allowed between "
-                       "symbols in the same section");
-    }
     const MCSymbol *B = &Target.getSymB()->getSymbol();
     MCSymbolData &B_SD = Asm.getSymbolData(*B);
 
-    FixedValue = Layout.getSymbolOffset(&A_SD) - Layout.getSymbolOffset(&B_SD);
+    // Offset of the symbol in the section
+    int64_t a = Layout.getSymbolOffset(&B_SD);
+
+    // Ofeset of the relocation in the section
+    int64_t b = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
 
+    FixedValue = b - a;
     // In the case where we have SymbA and SymB, we just need to store the delta
     // between the two symbols.  Update FixedValue to account for the delta, and
     // skip recording the relocation.
-    return;
+    if (!CrossSection)
+      return;
   } else {
     FixedValue = Target.getConstant();
   }
@@ -673,7 +678,7 @@ void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm,
   Reloc.Data.VirtualAddress = Layout.getFragmentOffset(Fragment);
 
   // Turn relocations for temporary symbols into section relocations.
-  if (coff_symbol->MCData->getSymbol().isTemporary()) {
+  if (coff_symbol->MCData->getSymbol().isTemporary() || CrossSection) {
     Reloc.Symb = coff_symbol->Section->Symbol;
     FixedValue += Layout.getFragmentOffset(coff_symbol->MCData->Fragment)
                 + coff_symbol->MCData->getOffset();
@@ -684,7 +689,12 @@ void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm,
 
   Reloc.Data.VirtualAddress += Fixup.getOffset();
 
-  switch ((unsigned)Fixup.getKind()) {
+  unsigned FixupKind = Fixup.getKind();
+
+  if (CrossSection)
+    FixupKind = FK_PCRel_4;
+
+  switch (FixupKind) {
   case FK_PCRel_4:
   case X86::reloc_riprel_4byte:
   case X86::reloc_riprel_4byte_movq_load: