Simplify the handling of pcrel relocations on ELF. Now we do the right thing

for all symbol differences and can drop the old EmitPCRelSymbolValue
method.

This also make getExprForFDESymbol on ELF equal to the one on MachO, and it
can be made non-virtual.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130634 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 2 deletions

diff --git a/lib/MC/MCAsmInfo.cpp b/lib/MC/MCAsmInfo.cpp
index b685c1a264..541dd080ac 100644
--- a/lib/MC/MCAsmInfo.cpp
+++ b/lib/MC/MCAsmInfo.cpp
@@ -13,9 +13,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCExpr.h"
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/Support/DataTypes.h"
+#include "llvm/Support/Dwarf.h"
 #include <cctype>
 #include <cstring>
 using namespace llvm;
@@ -111,12 +113,22 @@ unsigned MCAsmInfo::getSLEB128Size(int Value) {
 
 const MCExpr *
 MCAsmInfo::getExprForPersonalitySymbol(const MCSymbol *Sym,
+                                       unsigned Encoding,
                                        MCStreamer &Streamer) const {
-  return getExprForFDESymbol(Sym, Streamer);
+  return getExprForFDESymbol(Sym, Encoding, Streamer);
 }
 
 const MCExpr *
 MCAsmInfo::getExprForFDESymbol(const MCSymbol *Sym,
+                               unsigned Encoding,
                                MCStreamer &Streamer) const {
-  return MCSymbolRefExpr::Create(Sym, Streamer.getContext());
+  if (!(Encoding & dwarf::DW_EH_PE_pcrel))
+    return MCSymbolRefExpr::Create(Sym, Streamer.getContext());
+
+  MCContext &Context = Streamer.getContext();
+  const MCExpr *Res = MCSymbolRefExpr::Create(Sym, Context);
+  MCSymbol *PCSym = Context.CreateTempSymbol();
+  Streamer.EmitLabel(PCSym);
+  const MCExpr *PC = MCSymbolRefExpr::Create(PCSym, Context);
+  return MCBinaryExpr::CreateSub(Res, PC, Context);
 }