[MC/AsmParser] Avoid setting MCSymbol.IsUsed in some cases

[oota-llvm.git] / include / llvm / MC / MCSymbol.h

diff --git a/include/llvm/MC/MCSymbol.h b/include/llvm/MC/MCSymbol.h
index e52a34601b091da1ec162e1b2af0c3c07d391e9e..563fa803b0e4b2bc1f30d41891babae3585f1727 100644 (file)
--- a/include/llvm/MC/MCSymbol.h
+++ b/include/llvm/MC/MCSymbol.h
@@ -114,9 +114,14 @@ protected:
   /// The alignment is stored as log2(align) + 1.  This allows all values from
   /// 0 to 2^31 to be stored which is every power of 2 representable by an
   /// unsigned.
-  static const unsigned NumCommonAlignmentBits = 5;
+  enum : unsigned { NumCommonAlignmentBits = 5 };
   unsigned CommonAlignLog2 : NumCommonAlignmentBits;
 
+  /// The Flags field is used by object file implementations to store
+  /// additional per symbol information which is not easily classified.
+  enum : unsigned { NumFlagsBits = 16 };
+  mutable uint32_t Flags : NumFlagsBits;
+
   /// Index field, for use by the object file implementation.
   mutable uint32_t Index = 0;
 
@@ -131,10 +136,6 @@ protected:
     const MCExpr *Value;
   };
 
-  /// The Flags field is used by object file implementations to store
-  /// additional per symbol information which is not easily classified.
-  mutable uint32_t Flags = 0;
-
 protected: // MCContext creates and uniques these.
   friend class MCExpr;
   friend class MCContext;
@@ -152,7 +153,7 @@ protected: // MCContext creates and uniques these.
       : IsTemporary(isTemporary), IsRedefinable(false), IsUsed(false),
         IsRegistered(false), IsExternal(false), IsPrivateExtern(false),
         Kind(Kind), IsUsedInReloc(false), SymbolContents(SymContentsUnset),
-        CommonAlignLog2(0) {
+        CommonAlignLog2(0), Flags(0) {
     Offset = 0;
     SectionOrFragmentAndHasName.setInt(!!Name);
     if (Name)
@@ -178,7 +179,7 @@ private:
 
   MCSymbol(const MCSymbol &) = delete;
   void operator=(const MCSymbol &) = delete;
-  MCSection *getSectionPtr() const {
+  MCSection *getSectionPtr(bool SetUsed = true) const {
     if (MCFragment *F = getFragment())
       return F->getParent();
     const auto &SectionOrFragment = SectionOrFragmentAndHasName.getPointer();
@@ -186,7 +187,7 @@ private:
     MCSection *Section = SectionOrFragment.dyn_cast<MCSection *>();
     if (Section || !isVariable())
       return Section;
-    return Section = getVariableValue()->findAssociatedSection();
+    return Section = getVariableValue(SetUsed)->findAssociatedSection();
   }
 
   /// \brief Get a reference to the name field.  Requires that we have a name
@@ -222,7 +223,7 @@ public:
 
   /// isUsed - Check if this is used.
   bool isUsed() const { return IsUsed; }
-  void setUsed(bool Value) const { IsUsed = Value; }
+  void setUsed(bool Value) const { IsUsed |= Value; }
 
   /// \brief Check if this symbol is redefinable.
   bool isRedefinable() const { return IsRedefinable; }
@@ -247,22 +248,28 @@ public:
   /// isDefined - Check if this symbol is defined (i.e., it has an address).
   ///
   /// Defined symbols are either absolute or in some section.
-  bool isDefined() const { return getSectionPtr() != nullptr; }
+  bool isDefined(bool SetUsed = true) const {
+    return getSectionPtr(SetUsed) != nullptr;
+  }
 
   /// isInSection - Check if this symbol is defined in some section (i.e., it
   /// is defined but not absolute).
-  bool isInSection() const { return isDefined() && !isAbsolute(); }
+  bool isInSection(bool SetUsed = true) const {
+    return isDefined(SetUsed) && !isAbsolute(SetUsed);
+  }
 
   /// isUndefined - Check if this symbol undefined (i.e., implicitly defined).
-  bool isUndefined() const { return !isDefined(); }
+  bool isUndefined(bool SetUsed = true) const { return !isDefined(SetUsed); }
 
   /// isAbsolute - Check if this is an absolute symbol.
-  bool isAbsolute() const { return getSectionPtr() == AbsolutePseudoSection; }
+  bool isAbsolute(bool SetUsed = true) const {
+    return getSectionPtr(SetUsed) == AbsolutePseudoSection;
+  }
 
   /// Get the section associated with a defined, non-absolute symbol.
-  MCSection &getSection() const {
-    assert(isInSection() && "Invalid accessor!");
-    return *getSectionPtr();
+  MCSection &getSection(bool SetUsed = true) const {
+    assert(isInSection(SetUsed) && "Invalid accessor!");
+    return *getSectionPtr(SetUsed);
   }
 
   /// Mark the symbol as defined in the section \p S.
@@ -294,10 +301,10 @@ public:
     return SymbolContents == SymContentsVariable;
   }
 
-  /// getVariableValue() - Get the value for variable symbols.
-  const MCExpr *getVariableValue() const {
+  /// getVariableValue - Get the value for variable symbols.
+  const MCExpr *getVariableValue(bool SetUsed = true) const {
     assert(isVariable() && "Invalid accessor!");
-    IsUsed = true;
+    IsUsed |= SetUsed;
     return Value;
   }
 
@@ -402,10 +409,14 @@ protected:
   uint32_t getFlags() const { return Flags; }
 
   /// Set the (implementation defined) symbol flags.
-  void setFlags(uint32_t Value) const { Flags = Value; }
+  void setFlags(uint32_t Value) const {
+    assert(Value < (1U << NumFlagsBits) && "Out of range flags");
+    Flags = Value;
+  }
 
   /// Modify the flags via a mask
   void modifyFlags(uint32_t Value, uint32_t Mask) const {
+    assert(Value < (1U << NumFlagsBits) && "Out of range flags");
     Flags = (Flags & ~Mask) | Value;
   }
 };