Commit b61a4aac authored by Fangrui Song's avatar Fangrui Song
Browse files

[MC] Default MCContext::UseNamesOnTempLabels to false and only set it to true for MCAsmStreamer 

Only MCAsmStreamer (assembly output) needs to keep names of temporary labels created by
MCContext::createTempSymbol().

This change made the rL236642 optimization available for cc2as and
probably some other users.

This eliminates a behavior difference between llvm-mc -filetype=obj and cc1as, which caused
https://reviews.llvm.org/D74006#1890487

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D75097
parent d0c4277d

llvm/include/llvm/MC/MCContext.h

+1 −1
Original line number Diff line number Diff line
@@ -188,7 +188,7 @@ namespace llvm { 
    /// differences between temporary and non-temporary labels (primarily on

    /// Darwin).

    bool AllowTemporaryLabels = true;

    bool UseNamesOnTempLabels = true;

    bool UseNamesOnTempLabels = false;



    /// The Compile Unit ID that we are currently processing.

    unsigned DwarfCompileUnitID = 0;

llvm/lib/CodeGen/LLVMTargetMachine.cpp

+0 −3
Original line number Diff line number Diff line
@@ -157,9 +157,6 @@ bool LLVMTargetMachine::addAsmPrinter(PassManagerBase &PM, 
    if (!MCE || !MAB)

      return true;



    // Don't waste memory on names of temp labels.

    Context.setUseNamesOnTempLabels(false);



    Triple T(getTargetTriple().str());

    AsmStreamer.reset(getTarget().createMCObjectStreamer(

        T, Context, std::unique_ptr<MCAsmBackend>(MAB),

llvm/lib/MC/MCAsmStreamer.cpp

+2 −0
Original line number Diff line number Diff line
@@ -79,6 +79,8 @@ public: 
        InstPrinter->setCommentStream(CommentStream);

    if (Assembler->getBackendPtr())

      setAllowAutoPadding(Assembler->getBackend().allowAutoPadding());



    Context.setUseNamesOnTempLabels(true);

  }



  MCAssembler &getAssembler() { return *Assembler; }

llvm/tools/llvm-mc/llvm-mc.cpp

+0 −3
Original line number Diff line number Diff line
@@ -474,9 +474,6 @@ int main(int argc, char **argv) { 
  } else {

    assert(FileType == OFT_ObjectFile && "Invalid file type!");



    // Don't waste memory on names of temp labels.

    Ctx.setUseNamesOnTempLabels(false);



    if (!Out->os().supportsSeeking()) {

      BOS = std::make_unique<buffer_ostream>(Out->os());

      OS = BOS.get();

llvm/tools/llvm-ml/llvm-ml.cpp

+0 −3
Original line number Diff line number Diff line
@@ -333,9 +333,6 @@ int main(int argc, char **argv) { 
  } else {

    assert(FileType == OFT_ObjectFile && "Invalid file type!");



    // Don't waste memory on names of temp labels.

    Ctx.setUseNamesOnTempLabels(false);



    if (!Out->os().supportsSeeking()) {

      BOS = std::make_unique<buffer_ostream>(Out->os());

      OS = BOS.get();