Commit 6a9d7718 authored by Finkel, Hal's avatar Finkel, Hal
Browse files

Merging r222672: 

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r222672 | uweigand | 2014-11-24 18:09:47 +0000 (Mon, 24 Nov 2014) | 10 lines

[PowerPC] Fix PR 21652 - copy st_other bits on symbol assignment

When processing an assignment in the integrated assembler that sets
a symbol to the value of another symbol, we need to copy the st_other
bits that encode the local entry point offset.

Modeled after MipsTargetELFStreamer::emitAssignment handling of the
ELF::STO_MIPS_MICROMIPS flag.


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llvm-svn: 223743
parent fa81086d

llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp

+17 −0
Original line number Diff line number Diff line
@@ -184,6 +184,23 @@ public: 
    if ((Flags & ELF::EF_PPC64_ABI) == 0)

      MCA.setELFHeaderEFlags(Flags | 2);

  }

  void emitAssignment(MCSymbol *Symbol, const MCExpr *Value) override {

    // When encoding an assignment to set symbol A to symbol B, also copy

    // the st_other bits encoding the local entry point offset.

    if (Value->getKind() != MCExpr::SymbolRef)

      return;

    const MCSymbol &RhsSym =

        static_cast<const MCSymbolRefExpr *>(Value)->getSymbol();

    MCSymbolData &Data = getStreamer().getOrCreateSymbolData(&RhsSym);

    MCSymbolData &SymbolData = getStreamer().getOrCreateSymbolData(Symbol);

    // 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 = MCELF::getOther(SymbolData) << 2;

    Other &= ~ELF::STO_PPC64_LOCAL_MASK;

    Other |= (MCELF::getOther(Data) << 2) & ELF::STO_PPC64_LOCAL_MASK;

    MCELF::setOther(SymbolData, Other >> 2);

  }

};



class PPCTargetMachOStreamer : public PPCTargetStreamer {

llvm/test/MC/PowerPC/ppc64-localentry.s

+19 −0
Original line number Diff line number Diff line
@@ -35,6 +35,9 @@ caller_other: 
	nop

	.size caller_other, .-caller_other



copy1 = callee1

copy2 = callee2



# Verify that use of .localentry implies ABI version 2

# CHECK: ElfHeader {

# CHECK: Flags [ (0x2)
@@ -68,3 +71,19 @@ caller_other: 
# CHECK-NEXT:  Other: 0

# CHECK-NEXT:  Section: .text



# Verify that symbol assignment copies the Other bits.

# CHECK:       Name: copy1

# CHECK-NEXT:  Value:

# CHECK-NEXT:  Size: 16

# CHECK-NEXT:  Binding: Local

# CHECK-NEXT:  Type: Function

# CHECK-NEXT:  Other: 96

# CHECK-NEXT:  Section: .text

# CHECK:       Name: copy2

# CHECK-NEXT:  Value:

# CHECK-NEXT:  Size: 8

# CHECK-NEXT:  Binding: Local

# CHECK-NEXT:  Type: Function

# CHECK-NEXT:  Other: 0

# CHECK-NEXT:  Section: .text