[XRay] Merge instrumentation point table emission code into AsmPrinter.

Summary:
No need to have this per-architecture.  While there, unify 32-bit ARM's
behaviour with what changed elsewhere and start function names lowercase
as per the coding standards.  Individual entry emission code goes to the
entry's own class.

Fully tested on amd64, cross-builds on both ARMs and PowerPC.

Reviewers: dberris

Subscribers: aemerson, llvm-commits

Differential Revision: https://reviews.llvm.org/D28209

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290858 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 1 insertions, 55 deletions

diff --git a/lib/Target/AArch64/AArch64AsmPrinter.cpp b/lib/Target/AArch64/AArch64AsmPrinter.cpp
index b2d96a32fd3..efc22189378 100644
--- a/lib/Target/AArch64/AArch64AsmPrinter.cpp
+++ b/lib/Target/AArch64/AArch64AsmPrinter.cpp
@@ -76,7 +76,6 @@ public:
   void LowerPATCHABLE_FUNCTION_EXIT(const MachineInstr &MI);
   void LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI);
 
-  void EmitXRayTable();
   void EmitSled(const MachineInstr &MI, SledKind Kind);
 
   /// \brief tblgen'erated driver function for lowering simple MI->MC
@@ -95,7 +94,7 @@ public:
     AArch64FI = F.getInfo<AArch64FunctionInfo>();
     STI = static_cast<const AArch64Subtarget*>(&F.getSubtarget());
     bool Result = AsmPrinter::runOnMachineFunction(F);
-    EmitXRayTable();
+    emitXRayTable();
     return Result;
   }
 
@@ -150,59 +149,6 @@ void AArch64AsmPrinter::LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI)
   EmitSled(MI, SledKind::TAIL_CALL);
 }
 
-void AArch64AsmPrinter::EmitXRayTable()
-{
-  //TODO: merge the logic for ELF XRay sleds at a higher level, so to avoid
-  // code duplication as it is now for x86_64, ARM32 and AArch64.
-  if (Sleds.empty())
-    return;
-
-  auto PrevSection = OutStreamer->getCurrentSectionOnly();
-  auto Fn = MF->getFunction();
-  MCSection *Section;
-
-  if (STI->isTargetELF()) {
-    if (Fn->hasComdat())
-      Section = OutContext.getELFSection("xray_instr_map", ELF::SHT_PROGBITS,
-        ELF::SHF_ALLOC | ELF::SHF_GROUP, 0,
-        Fn->getComdat()->getName());
-    else
-      Section = OutContext.getELFSection("xray_instr_map", ELF::SHT_PROGBITS,
-        ELF::SHF_ALLOC);
-  } else if (STI->isTargetMachO()) {
-    Section = OutContext.getMachOSection("__DATA", "xray_instr_map", 0,
-                                         SectionKind::getReadOnlyWithRel());
-  } else {
-    llvm_unreachable("Unsupported target");
-  }
-
-  // Before we switch over, we force a reference to a label inside the
-  // xray_instr_map section. Since EmitXRayTable() is always called just
-  // before the function's end, we assume that this is happening after the
-  // last return instruction.
-  //
-  // We then align the reference to 16 byte boundaries, which we determined
-  // experimentally to be beneficial to avoid causing decoder stalls.
-  MCSymbol *Tmp = OutContext.createTempSymbol("xray_synthetic_", true);
-  OutStreamer->EmitCodeAlignment(16);
-  OutStreamer->EmitSymbolValue(Tmp, 8, false);
-  OutStreamer->SwitchSection(Section);
-  OutStreamer->EmitLabel(Tmp);
-  for (const auto &Sled : Sleds) {
-    OutStreamer->EmitSymbolValue(Sled.Sled, 8);
-    OutStreamer->EmitSymbolValue(CurrentFnSym, 8);
-    auto Kind = static_cast<uint8_t>(Sled.Kind);
-    OutStreamer->EmitBytes(
-      StringRef(reinterpret_cast<const char *>(&Kind), 1));
-    OutStreamer->EmitBytes(
-      StringRef(reinterpret_cast<const char *>(&Sled.AlwaysInstrument), 1));
-    OutStreamer->EmitZeros(14);
-  }
-  OutStreamer->SwitchSection(PrevSection);
-
-  Sleds.clear();
-}
-
 void AArch64AsmPrinter::EmitSled(const MachineInstr &MI, SledKind Kind)
 {
   static const int8_t NoopsInSledCount = 7;