simplify asmprinter: only emit .set directives when entries have

EK_LabelDifference32 kind and the target has .set support.  Simplify
X86AsmPrinter::printPICJumpTableSetLabel to make use of recent helpers.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94518 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2010-01-26 05:15:20 +00:00
parent 6bf1def159
commit e35df92eca
2 changed files with 9 additions and 16 deletions

View File

@ -511,14 +511,16 @@ void AsmPrinter::EmitJumpTableInfo(MachineFunction &MF) {
// If this jump table was deleted, ignore it.
if (JTBBs.empty()) continue;
// For PIC codegen, if possible we want to use the SetDirective to reduce
// the number of relocations the assembler will generate for the jump table.
// Set directives are all printed before the jump table itself.
SmallPtrSet<MachineBasicBlock*, 16> EmittedSets;
if (MAI->getSetDirective() && IsPic)
// For the EK_LabelDifference32 entry, if the target supports .set, emit a
// .set directive for each unique entry. This reduces the number of
// relocations the assembler will generate for the jump table.
if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
MAI->getSetDirective()) {
SmallPtrSet<MachineBasicBlock*, 16> EmittedSets;
for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
if (EmittedSets.insert(JTBBs[ii]))
printPICJumpTableSetLabel(i, JTBBs[ii]);
}
// On some targets (e.g. Darwin) we want to emit two consequtive labels
// before each jump table. The first label is never referenced, but tells

View File

@ -455,17 +455,8 @@ void X86AsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
void X86AsmPrinter::printPICJumpTableSetLabel(unsigned uid,
const MachineBasicBlock *MBB) const {
if (!MAI->getSetDirective())
return;
// We don't need .set machinery if we have GOT-style relocations
if (Subtarget->isPICStyleGOT()) // X86-32 on ELF.
return;
O << MAI->getSetDirective() << ' ' << MAI->getPrivateGlobalPrefix()
<< getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
O << *MBB->getSymbol(OutContext);
O << MAI->getSetDirective() << ' ' << *GetJTSetSymbol(uid, MBB->getNumber())
<< ',' << *MBB->getSymbol(OutContext);
if (Subtarget->isPICStyleRIPRel())
O << '-' << *GetJTISymbol(uid) << '\n';