Better fix for ARM MOVT relocation encoding of thumb bit.

Replaces r145318 with a more targetted fix for the relocation handling.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145346 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 16 insertions, 9 deletions

diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp
index 802bb8e..29adbcb 100644
--- a/lib/MC/MCAssembler.cpp
+++ b/lib/MC/MCAssembler.cpp
@@ -273,17 +273,13 @@ bool MCAssembler::EvaluateFixup(const MCAsmLayout &Layout,
 
   Value = Target.getConstant();
 
-  bool SetThumbBit = false;
+  bool IsThumb = false;
   if (const MCSymbolRefExpr *A = Target.getSymA()) {
     const MCSymbol &Sym = A->getSymbol().AliasedSymbol();
     if (Sym.isDefined())
       Value += Layout.getSymbolOffset(&getSymbolData(Sym));
-    // ARM data fixups based from a thumb function address need to have the low
-    // bit set. The actual value is always at least 16-bit aligned, so the
-    // low bit is normally clear and available for use as an ISA flag for
-    // interworking.
-    if (Fixup.getKind() == FK_Data_4 && isThumbFunc(&Sym))
-      SetThumbBit = true;
+    if (isThumbFunc(&Sym))
+      IsThumb = true;
   }
   if (const MCSymbolRefExpr *B = Target.getSymB()) {
     const MCSymbol &Sym = B->getSymbol().AliasedSymbol();
@@ -306,7 +302,11 @@ bool MCAssembler::EvaluateFixup(const MCAsmLayout &Layout,
     Value -= Offset;
   }
 
-  if (SetThumbBit)
+  // ARM fixups based from a thumb function address need to have the low
+  // bit set. The actual value is always at least 16-bit aligned, so the
+  // low bit is normally clear and available for use as an ISA flag for
+  // interworking.
+  if (IsThumb)
     Value |= 1;
 
   return IsResolved;
diff --git a/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp b/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
index 352c73e..f394b4f 100644
--- a/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
+++ b/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
@@ -16,6 +16,7 @@
 #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"
@@ -178,9 +179,16 @@ 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 +197,6 @@ RecordARMMovwMovtRelocation(MachObjectWriter *Writer,
     break;
   }
 
-
   if (Type == macho::RIT_ARM_HalfDifference) {
     uint32_t OtherHalf = MovtBit
       ? (FixedValue & 0xffff) : ((FixedValue & 0xffff0000) >> 16);