Optimize the creation of mapping symbols.

[oota-llvm.git] / lib / Target / AArch64 / MCTargetDesc / AArch64MCAsmInfo.cpp

diff --git a/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp b/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp
index 189d4eba81a35166e4110b1508fb5c98a1a07cef..921c4b94a7299d313c38c123bdd1767b0caf2409 100644 (file)
--- a/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp
+++ b/lib/Target/AArch64/MCTargetDesc/AArch64MCAsmInfo.cpp
@@ -12,32 +12,94 @@
 //===----------------------------------------------------------------------===//
 
 #include "AArch64MCAsmInfo.h"
-
+#include "llvm/ADT/Triple.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/Support/CommandLine.h"
 using namespace llvm;
 
-AArch64ELFMCAsmInfo::AArch64ELFMCAsmInfo() {
+enum AsmWriterVariantTy {
+  Default = -1,
+  Generic = 0,
+  Apple = 1
+};
+
+static cl::opt<AsmWriterVariantTy> AsmWriterVariant(
+    "aarch64-neon-syntax", cl::init(Default),
+    cl::desc("Choose style of NEON code to emit from AArch64 backend:"),
+    cl::values(clEnumValN(Generic, "generic", "Emit generic NEON assembly"),
+               clEnumValN(Apple, "apple", "Emit Apple-style NEON assembly"),
+               clEnumValEnd));
+
+AArch64MCAsmInfoDarwin::AArch64MCAsmInfoDarwin() {
+  // We prefer NEON instructions to be printed in the short form.
+  AssemblerDialect = AsmWriterVariant == Default ? 1 : AsmWriterVariant;
+
+  PrivateGlobalPrefix = "L";
+  PrivateLabelPrefix = "L";
+  SeparatorString = "%%";
+  CommentString = ";";
+  PointerSize = CalleeSaveStackSlotSize = 8;
+
+  AlignmentIsInBytes = false;
+  UsesELFSectionDirectiveForBSS = true;
+  SupportsDebugInformation = true;
+  UseDataRegionDirectives = true;
+
+  ExceptionsType = ExceptionHandling::DwarfCFI;
+
+  // AArch64 Darwin doesn't have the baggage of X86/ARM, so it's fine to use
+  // LShr instead of AShr.
+  UseLogicalShr = true;
+}
+
+const MCExpr *AArch64MCAsmInfoDarwin::getExprForPersonalitySymbol(
+    const MCSymbol *Sym, unsigned Encoding, MCStreamer &Streamer) const {
+  // On Darwin, we can reference dwarf symbols with foo@GOT-., which
+  // is an indirect pc-relative reference. The default implementation
+  // won't reference using the GOT, so we need this target-specific
+  // version.
+  MCContext &Context = Streamer.getContext();
+  const MCExpr *Res =
+      MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOT, Context);
+  MCSymbol *PCSym = Context.createTempSymbol();
+  Streamer.EmitLabel(PCSym);
+  const MCExpr *PC = MCSymbolRefExpr::create(PCSym, Context);
+  return MCBinaryExpr::createSub(Res, PC, Context);
+}
+
+AArch64MCAsmInfoELF::AArch64MCAsmInfoELF(const Triple &T) {
+  if (T.getArch() == Triple::aarch64_be)
+    IsLittleEndian = false;
+
+  // We prefer NEON instructions to be printed in the short form.
+  AssemblerDialect = AsmWriterVariant == Default ? 0 : AsmWriterVariant;
+
   PointerSize = 8;
 
   // ".comm align is in bytes but .align is pow-2."
   AlignmentIsInBytes = false;
 
   CommentString = "//";
+  PrivateGlobalPrefix = ".L";
+  PrivateLabelPrefix = ".L";
   Code32Directive = ".code\t32";
 
   Data16bitsDirective = "\t.hword\t";
   Data32bitsDirective = "\t.word\t";
   Data64bitsDirective = "\t.xword\t";
 
-  UseDataRegionDirectives = true;
+  UseDataRegionDirectives = false;
+
+  WeakRefDirective = "\t.weak\t";
 
-  HasLEB128 = true;
   SupportsDebugInformation = true;
 
   // Exceptions handling
   ExceptionsType = ExceptionHandling::DwarfCFI;
 
   UseIntegratedAssembler = true;
-}
 
-// Pin the vtable to this file.
-void AArch64ELFMCAsmInfo::anchor() {}
+  HasIdentDirective = true;
+}