1 files changed, 85 insertions, 31 deletions
diff --git a/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp b/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
index 352c73e..8057cb6 100644
--- a/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
+++ b/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
@@ -13,9 +13,11 @@
 #include "llvm/MC/MCAssembler.h"
 #include "llvm/MC/MCAsmLayout.h"
 #include "llvm/MC/MCMachObjectWriter.h"
+#include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCExpr.h"
 #include "llvm/MC/MCFixup.h"
 #include "llvm/MC/MCFixupKindInfo.h"
+#include "llvm/MC/MCMachOSymbolFlags.h"
 #include "llvm/MC/MCValue.h"
 #include "llvm/Object/MachOFormat.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -32,12 +34,12 @@ class ARMMachObjectWriter : public MCMachObjectTargetWriter {
                                     MCValue Target,
                                     unsigned Log2Size,
                                     uint64_t &FixedValue);
-  void RecordARMMovwMovtRelocation(MachObjectWriter *Writer,
-                                   const MCAssembler &Asm,
-                                   const MCAsmLayout &Layout,
-                                   const MCFragment *Fragment,
-                                   const MCFixup &Fixup, MCValue Target,
-                                   uint64_t &FixedValue);
+  void RecordARMScatteredHalfRelocation(MachObjectWriter *Writer,
+                                        const MCAssembler &Asm,
+                                        const MCAsmLayout &Layout,
+                                        const MCFragment *Fragment,
+                                        const MCFixup &Fixup, MCValue Target,
+                                        uint64_t &FixedValue);
 
 public:
   ARMMachObjectWriter(bool Is64Bit, uint32_t CPUType,
@@ -80,6 +82,9 @@ static bool getARMFixupKindMachOInfo(unsigned Kind, unsigned &RelocType,
   case ARM::fixup_arm_adr_pcrel_12:
   case ARM::fixup_arm_condbranch:
   case ARM::fixup_arm_uncondbranch:
+  case ARM::fixup_arm_uncondbl:
+  case ARM::fixup_arm_condbl:
+  case ARM::fixup_arm_blx:
     RelocType = unsigned(macho::RIT_ARM_Branch24Bit);
     // Report as 'long', even though that is not quite accurate.
     Log2Size = llvm::Log2_32(4);
@@ -98,34 +103,47 @@ static bool getARMFixupKindMachOInfo(unsigned Kind, unsigned &RelocType,
     Log2Size = llvm::Log2_32(4);
     return true;
 
+  // For movw/movt r_type relocations they always have a pair following them and
+  // the r_length bits are used differently.  The encoding of the r_length is as
+  // follows:
+  //   low bit of r_length:
+  //      0 - :lower16: for movw instructions
+  //      1 - :upper16: for movt instructions
+  //   high bit of r_length:
+  //      0 - arm instructions
+  //      1 - thumb instructions
   case ARM::fixup_arm_movt_hi16:
   case ARM::fixup_arm_movt_hi16_pcrel:
+    RelocType = unsigned(macho::RIT_ARM_Half);
+    Log2Size = 1;
+    return true;
   case ARM::fixup_t2_movt_hi16:
   case ARM::fixup_t2_movt_hi16_pcrel:
-    RelocType = unsigned(macho::RIT_ARM_HalfDifference);
-    // Report as 'long', even though that is not quite accurate.
-    Log2Size = llvm::Log2_32(4);
+    RelocType = unsigned(macho::RIT_ARM_Half);
+    Log2Size = 3;
     return true;
 
   case ARM::fixup_arm_movw_lo16:
   case ARM::fixup_arm_movw_lo16_pcrel:
+    RelocType = unsigned(macho::RIT_ARM_Half);
+    Log2Size = 0;
+    return true;
   case ARM::fixup_t2_movw_lo16:
   case ARM::fixup_t2_movw_lo16_pcrel:
     RelocType = unsigned(macho::RIT_ARM_Half);
-    // Report as 'long', even though that is not quite accurate.
-    Log2Size = llvm::Log2_32(4);
+    Log2Size = 2;
     return true;
   }
 }
 
 void ARMMachObjectWriter::
-RecordARMMovwMovtRelocation(MachObjectWriter *Writer,
-                            const MCAssembler &Asm,
-                            const MCAsmLayout &Layout,
-                            const MCFragment *Fragment,
-                            const MCFixup &Fixup,
-                            MCValue Target,
-                            uint64_t &FixedValue) {
+RecordARMScatteredHalfRelocation(MachObjectWriter *Writer,
+                                 const MCAssembler &Asm,
+                                 const MCAsmLayout &Layout,
+                                 const MCFragment *Fragment,
+                                 const MCFixup &Fixup,
+                                 MCValue Target,
+                                 uint64_t &FixedValue) {
   uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset();
   unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
   unsigned Type = macho::RIT_ARM_Half;
@@ -135,7 +153,8 @@ RecordARMMovwMovtRelocation(MachObjectWriter *Writer,
   MCSymbolData *A_SD = &Asm.getSymbolData(*A);
 
   if (!A_SD->getFragment())
-    report_fatal_error("symbol '" + A->getName() +
+    Asm.getContext().FatalError(Fixup.getLoc(),
+                       "symbol '" + A->getName() +
                        "' can not be undefined in a subtraction expression");
 
   uint32_t Value = Writer->getSymbolAddress(A_SD, Layout);
@@ -148,7 +167,8 @@ RecordARMMovwMovtRelocation(MachObjectWriter *Writer,
     MCSymbolData *B_SD = &Asm.getSymbolData(B->getSymbol());
 
     if (!B_SD->getFragment())
-      report_fatal_error("symbol '" + B->getSymbol().getName() +
+      Asm.getContext().FatalError(Fixup.getLoc(),
+                         "symbol '" + B->getSymbol().getName() +
                          "' can not be undefined in a subtraction expression");
 
     // Select the appropriate difference relocation type.
@@ -178,9 +198,16 @@ RecordARMMovwMovtRelocation(MachObjectWriter *Writer,
   case ARM::fixup_arm_movt_hi16:
   case ARM::fixup_arm_movt_hi16_pcrel:
     MovtBit = 1;
+    // The thumb bit shouldn't be set in the 'other-half' bit of the
+    // relocation, but it will be set in FixedValue if the base symbol
+    // is a thumb function. Clear it out here.
+    if (A_SD->getFlags() & SF_ThumbFunc)
+      FixedValue &= 0xfffffffe;
     break;
   case ARM::fixup_t2_movt_hi16:
   case ARM::fixup_t2_movt_hi16_pcrel:
+    if (A_SD->getFlags() & SF_ThumbFunc)
+      FixedValue &= 0xfffffffe;
     MovtBit = 1;
     // Fallthrough
   case ARM::fixup_t2_movw_lo16:
@@ -189,7 +216,6 @@ RecordARMMovwMovtRelocation(MachObjectWriter *Writer,
     break;
   }
 
-
   if (Type == macho::RIT_ARM_HalfDifference) {
     uint32_t OtherHalf = MovtBit
       ? (FixedValue & 0xffff) : ((FixedValue & 0xffff0000) >> 16);
@@ -233,7 +259,8 @@ void ARMMachObjectWriter::RecordARMScatteredRelocation(MachObjectWriter *Writer,
   MCSymbolData *A_SD = &Asm.getSymbolData(*A);
 
   if (!A_SD->getFragment())
-    report_fatal_error("symbol '" + A->getName() +
+    Asm.getContext().FatalError(Fixup.getLoc(),
+                       "symbol '" + A->getName() +
                        "' can not be undefined in a subtraction expression");
 
   uint32_t Value = Writer->getSymbolAddress(A_SD, Layout);
@@ -245,7 +272,8 @@ void ARMMachObjectWriter::RecordARMScatteredRelocation(MachObjectWriter *Writer,
     MCSymbolData *B_SD = &Asm.getSymbolData(B->getSymbol());
 
     if (!B_SD->getFragment())
-      report_fatal_error("symbol '" + B->getSymbol().getName() +
+      Asm.getContext().FatalError(Fixup.getLoc(),
+                         "symbol '" + B->getSymbol().getName() +
                          "' can not be undefined in a subtraction expression");
 
     // Select the appropriate difference relocation type.
@@ -287,19 +315,21 @@ void ARMMachObjectWriter::RecordRelocation(MachObjectWriter *Writer,
   unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
   unsigned Log2Size;
   unsigned RelocType = macho::RIT_Vanilla;
-  if (!getARMFixupKindMachOInfo(Fixup.getKind(), RelocType, Log2Size)) {
-    report_fatal_error("unknown ARM fixup kind!");
-    return;
-  }
+  if (!getARMFixupKindMachOInfo(Fixup.getKind(), RelocType, Log2Size))
+    // If we failed to get fixup kind info, it's because there's no legal
+    // relocation type for the fixup kind. This happens when it's a fixup that's
+    // expected to always be resolvable at assembly time and not have any
+    // relocations needed.
+    Asm.getContext().FatalError(Fixup.getLoc(),
+                                "unsupported relocation on symbol");
 
   // If this is a difference or a defined symbol plus an offset, then we need a
   // scattered relocation entry.  Differences always require scattered
   // relocations.
   if (Target.getSymB()) {
-    if (RelocType == macho::RIT_ARM_Half ||
-        RelocType == macho::RIT_ARM_HalfDifference)
-      return RecordARMMovwMovtRelocation(Writer, Asm, Layout, Fragment, Fixup,
-                                         Target, FixedValue);
+    if (RelocType == macho::RIT_ARM_Half)
+      return RecordARMScatteredHalfRelocation(Writer, Asm, Layout, Fragment,
+                                              Fixup, Target, FixedValue);
     return RecordARMScatteredRelocation(Writer, Asm, Layout, Fragment, Fixup,
                                         Target, Log2Size, FixedValue);
   }
@@ -374,6 +404,30 @@ void ARMMachObjectWriter::RecordRelocation(MachObjectWriter *Writer,
                (Log2Size  << 25) |
                (IsExtern  << 27) |
                (Type      << 28));
+
+  // Even when it's not a scattered relocation, movw/movt always uses
+  // a PAIR relocation.
+  if (Type == macho::RIT_ARM_Half) {
+    // The other-half value only gets populated for the movt relocation.
+    uint32_t Value = 0;;
+    switch ((unsigned)Fixup.getKind()) {
+    default: break;
+    case ARM::fixup_arm_movt_hi16:
+    case ARM::fixup_arm_movt_hi16_pcrel:
+    case ARM::fixup_t2_movt_hi16:
+    case ARM::fixup_t2_movt_hi16_pcrel:
+      Value = FixedValue;
+      break;
+    }
+    macho::RelocationEntry MREPair;
+    MREPair.Word0 = Value;
+    MREPair.Word1 = ((0xffffff) |
+                     (Log2Size << 25) |
+                     (macho::RIT_Pair << 28));
+
+    Writer->addRelocation(Fragment->getParent(), MREPair);
+  }
+
   Writer->addRelocation(Fragment->getParent(), MRE);
 }