sets bit 0 of the function address of thumb function in .symtab

("T is 1 if the target symbol S has type STT_FUNC and the
symbol addresses a Thumb instruction ;it is 0 otherwise."
from "ELF for the ARM Architecture" 4.7.1.2)

Patch by Koan-Sin Tan!

llvm-svn: 131406

4 files changed, 16 insertions, 5 deletions

diff --git a/llvm/lib/MC/ELFObjectWriter.cpp b/llvm/lib/MC/ELFObjectWriter.cpp
index 5b54e55d899..0aaf7708479 100644
--- a/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/llvm/lib/MC/ELFObjectWriter.cpp
@@ -193,8 +193,13 @@ uint64_t ELFObjectWriter::SymbolValue(MCSymbolData &Data,
   if (!Symbol.isInSection())
     return 0;
 
-  if (Data.getFragment())
-    return Layout.getSymbolOffset(&Data);
+
+  if (Data.getFragment()) {
+    if (Data.getFlags() & ELF_Other_ThumbFunc)
+      return Layout.getSymbolOffset(&Data)+1;
+    else
+      return Layout.getSymbolOffset(&Data);
+  }
 
   return 0;
 }
diff --git a/llvm/lib/MC/MCAsmStreamer.cpp b/llvm/lib/MC/MCAsmStreamer.cpp
index 603ae837b6d..ee68a377e31 100644
--- a/llvm/lib/MC/MCAsmStreamer.cpp
+++ b/llvm/lib/MC/MCAsmStreamer.cpp
@@ -323,7 +323,8 @@ void MCAsmStreamer::EmitThumbFunc(MCSymbol *Func) {
   // This needs to emit to a temporary string to get properly quoted
   // MCSymbols when they have spaces in them.
   OS << "\t.thumb_func";
-  if (Func)
+  // Only Mach-O hasSubsectionsViaSymbols()
+  if (MAI.hasSubsectionsViaSymbols())
     OS << '\t' << *Func;
   EmitEOL();
 }
diff --git a/llvm/lib/MC/MCELF.cpp b/llvm/lib/MC/MCELF.cpp
index ce7783e2862..2c3f8e8f786 100644
--- a/llvm/lib/MC/MCELF.cpp
+++ b/llvm/lib/MC/MCELF.cpp
@@ -57,13 +57,13 @@ void MCELF::SetVisibility(MCSymbolData &SD, unsigned Visibility) {
   assert(Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_INTERNAL ||
          Visibility == ELF::STV_HIDDEN || Visibility == ELF::STV_PROTECTED);
 
-  uint32_t OtherFlags = SD.getFlags() & ~(0xf << ELF_STV_Shift);
+  uint32_t OtherFlags = SD.getFlags() & ~(0x3 << ELF_STV_Shift);
   SD.setFlags(OtherFlags | (Visibility << ELF_STV_Shift));
 }
 
 unsigned MCELF::GetVisibility(MCSymbolData &SD) {
   unsigned Visibility =
-    (SD.getFlags() & (0xf << ELF_STV_Shift)) >> ELF_STV_Shift;
+    (SD.getFlags() & (0x3 << ELF_STV_Shift)) >> ELF_STV_Shift;
   assert(Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_INTERNAL ||
          Visibility == ELF::STV_HIDDEN || Visibility == ELF::STV_PROTECTED);
   return Visibility;
diff --git a/llvm/lib/MC/MCELFStreamer.cpp b/llvm/lib/MC/MCELFStreamer.cpp
index 7808e76203f..bbb2789ea81 100644
--- a/llvm/lib/MC/MCELFStreamer.cpp
+++ b/llvm/lib/MC/MCELFStreamer.cpp
@@ -66,6 +66,11 @@ void MCELFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
 
 void MCELFStreamer::EmitThumbFunc(MCSymbol *Func) {
   // FIXME: Anything needed here to flag the function as thumb?
+
+  getAssembler().setIsThumbFunc(Func);
+
+  MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Func);
+  SD.setFlags(SD.getFlags() | ELF_Other_ThumbFunc);
 }
 
 void MCELFStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {