From e2fdf8d60e552869c3ee37104204ec3e67347df2 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Thu, 21 May 2015 17:00:40 +0000
Subject: [PATCH] Avoid unnecessary section switching. NFC.

llvm-svn: 237913
---
 llvm/include/llvm/MC/MCObjectStreamer.h | 4 ++--
 llvm/include/llvm/MC/MCStreamer.h       | 2 +-
 llvm/lib/MC/MCContext.cpp               | 3 +--
 3 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/llvm/include/llvm/MC/MCObjectStreamer.h b/llvm/include/llvm/MC/MCObjectStreamer.h
index 1a1222562f15..c990534e5383 100644
--- a/llvm/include/llvm/MC/MCObjectStreamer.h
+++ b/llvm/include/llvm/MC/MCObjectStreamer.h
@@ -147,8 +147,8 @@ public:
   bool emitAbsoluteSymbolDiff(const MCSymbol *Hi, const MCSymbol *Lo,
                               unsigned Size) override;
 
-  bool mayHaveInstructions() const override {
-    return getCurrentSectionData()->hasInstructions();
+  bool mayHaveInstructions(const MCSection &Sec) const override {
+    return Assembler->getOrCreateSectionData(Sec).hasInstructions();
   }
 };
 
diff --git a/llvm/include/llvm/MC/MCStreamer.h b/llvm/include/llvm/MC/MCStreamer.h
index 3dec9491a265..9f679c2482fb 100644
--- a/llvm/include/llvm/MC/MCStreamer.h
+++ b/llvm/include/llvm/MC/MCStreamer.h
@@ -728,7 +728,7 @@ public:
   /// \brief Finish emission of machine code.
   void Finish();
 
-  virtual bool mayHaveInstructions() const { return true; }
+  virtual bool mayHaveInstructions(const MCSection &Sec) const { return true; }
 };
 
 /// Create a dummy machine code streamer, which does nothing. This is useful for
diff --git a/llvm/lib/MC/MCContext.cpp b/llvm/lib/MC/MCContext.cpp
index bbff9b7c6a55..cbc130f6bfa9 100644
--- a/llvm/lib/MC/MCContext.cpp
+++ b/llvm/lib/MC/MCContext.cpp
@@ -442,8 +442,7 @@ bool MCContext::isValidDwarfFileNumber(unsigned FileNumber, unsigned CUID) {
 void MCContext::finalizeDwarfSections(MCStreamer &MCOS) {
   std::vector<const MCSection *> Keep;
   for (const MCSection *Sec : SectionsForRanges) {
-    MCOS.SwitchSection(Sec); // FIXME: pass the section to mayHaveInstructions
-    if (MCOS.mayHaveInstructions())
+    if (MCOS.mayHaveInstructions(*Sec))
       Keep.push_back(Sec);
   }
   SectionsForRanges.clear();