Bring back r239006 with a fix.

The fix is just that getOther had not been updated for packing the st_other
values in fewer bits and could return spurious values:

-  unsigned Other = (getFlags() & (0x3f << ELF_STO_Shift)) >> ELF_STO_Shift;
+  unsigned Other = (getFlags() & (0x7 << ELF_STO_Shift)) >> ELF_STO_Shift;

Original message:

Pack the MCSymbolELF bit fields into MCSymbol's Flags.

This reduces MCSymolfELF from 64 bytes to 56 bytes on x86_64.

While at it, also make getOther/setOther easier to use by accepting unshifted
STO_* values.

llvm-svn: 239012

4 files changed, 10 insertions, 25 deletions

diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
index 82ae41330bc..982a7f54e82 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
@@ -384,7 +384,7 @@ bool MipsELFObjectWriter::needsRelocateWithSymbol(const MCSymbol &Sym,
     return true;
 
   case ELF::R_MIPS_32:
-    if (cast<MCSymbolELF>(Sym).getOther() & (ELF::STO_MIPS_MICROMIPS >> 2))
+    if (cast<MCSymbolELF>(Sym).getOther() & ELF::STO_MIPS_MICROMIPS)
       return true;
     // falltrough
   case ELF::R_MIPS_26:
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFStreamer.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFStreamer.cpp
index d1e3a47f94b..b45d9cf621d 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFStreamer.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFStreamer.cpp
@@ -44,10 +44,7 @@ void MipsELFStreamer::createPendingLabelRelocs() {
     for (auto *L : Labels) {
       auto *Label = cast<MCSymbolELF>(L);
       getAssembler().registerSymbol(*Label);
-      // The "other" values are stored in the last 6 bits of the second byte.
-      // The traditional defines for STO values assume the full byte and thus
-      // the shift to pack it.
-      Label->setOther(ELF::STO_MIPS_MICROMIPS >> 2);
+      Label->setOther(ELF::STO_MIPS_MICROMIPS);
     }
   }
 
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
index 787d9a7b450..a051f4c123f 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
@@ -462,10 +462,7 @@ void MipsTargetELFStreamer::emitLabel(MCSymbol *S) {
   if (Type != ELF::STT_FUNC)
     return;
 
-  // The "other" values are stored in the last 6 bits of the second byte
-  // The traditional defines for STO values assume the full byte and thus
-  // the shift to pack it.
-  Symbol->setOther(ELF::STO_MIPS_MICROMIPS >> 2);
+  Symbol->setOther(ELF::STO_MIPS_MICROMIPS);
 }
 
 void MipsTargetELFStreamer::finish() {
@@ -527,13 +524,10 @@ void MipsTargetELFStreamer::emitAssignment(MCSymbol *S, const MCExpr *Value) {
   const auto &RhsSym = cast<MCSymbolELF>(
       static_cast<const MCSymbolRefExpr *>(Value)->getSymbol());
 
-  if (!(RhsSym.getOther() & (ELF::STO_MIPS_MICROMIPS >> 2)))
+  if (!(RhsSym.getOther() & ELF::STO_MIPS_MICROMIPS))
     return;
 
-  // The "other" values are stored in the last 6 bits of the second byte.
-  // The traditional defines for STO values assume the full byte and thus
-  // the shift to pack it.
-  Symbol->setOther(ELF::STO_MIPS_MICROMIPS >> 2);
+  Symbol->setOther(ELF::STO_MIPS_MICROMIPS);
 }
 
 MCELFStreamer &MipsTargetELFStreamer::getStreamer() {
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp
index 0f9697bb141..aba262c3b1f 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp
@@ -169,13 +169,10 @@ public:
     if (Res != ELF::decodePPC64LocalEntryOffset(Encoded))
       report_fatal_error(".localentry expression cannot be encoded.");
 
-    // The "other" values are stored in the last 6 bits of the second byte.
-    // The traditional defines for STO values assume the full byte and thus
-    // the shift to pack it.
-    unsigned Other = S->getOther() << 2;
+    unsigned Other = S->getOther();
     Other &= ~ELF::STO_PPC64_LOCAL_MASK;
     Other |= Encoded;
-    S->setOther(Other >> 2);
+    S->setOther(Other);
 
     // For GAS compatibility, unless we already saw a .abiversion directive,
     // set e_flags to indicate ELFv2 ABI.
@@ -191,13 +188,10 @@ public:
       return;
     const auto &RhsSym = cast<MCSymbolELF>(
         static_cast<const MCSymbolRefExpr *>(Value)->getSymbol());
-    // The "other" values are stored in the last 6 bits of the second byte.
-    // The traditional defines for STO values assume the full byte and thus
-    // the shift to pack it.
-    unsigned Other = Symbol->getOther() << 2;
+    unsigned Other = Symbol->getOther();
     Other &= ~ELF::STO_PPC64_LOCAL_MASK;
-    Other |= (RhsSym.getOther() << 2) & ELF::STO_PPC64_LOCAL_MASK;
-    Symbol->setOther(Other >> 2);
+    Other |= RhsSym.getOther() & ELF::STO_PPC64_LOCAL_MASK;
+    Symbol->setOther(Other);
   }
 };