make isVirtualSection a virtual method on MCSection. Chris' suggestion.

llvm-svn: 119547

5 files changed, 21 insertions, 7 deletions

diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp
index c80dc3c2483..a23bab25a4d 100644
--- a/llvm/lib/MC/MCAssembler.cpp
+++ b/llvm/lib/MC/MCAssembler.cpp
@@ -54,10 +54,10 @@ MCAsmLayout::MCAsmLayout(MCAssembler &Asm)
  {
   // Compute the section layout order. Virtual sections must go last.
   for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it)
-    if (!Asm.getBackend().isVirtualSection(it->getSection()))
+    if (!it->getSection().isVirtualSection())
       SectionOrder.push_back(&*it);
   for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it)
-    if (Asm.getBackend().isVirtualSection(it->getSection()))
+    if (it->getSection().isVirtualSection())
       SectionOrder.push_back(&*it);
 }
 
@@ -157,7 +157,7 @@ uint64_t MCAsmLayout::getSectionAddressSize(const MCSectionData *SD) const {
 
 uint64_t MCAsmLayout::getSectionFileSize(const MCSectionData *SD) const {
   // Virtual sections have no file size.
-  if (getAssembler().getBackend().isVirtualSection(SD->getSection()))
+  if (SD->getSection().isVirtualSection())
     return 0;
 
   // Otherwise, the file size is the same as the address space size.
@@ -541,7 +541,7 @@ void MCAssembler::WriteSectionData(const MCSectionData *SD,
                                    const MCAsmLayout &Layout,
                                    MCObjectWriter *OW) const {
   // Ignore virtual sections.
-  if (getBackend().isVirtualSection(SD->getSection())) {
+  if (SD->getSection().isVirtualSection()) {
     assert(Layout.getSectionFileSize(SD) == 0 && "Invalid size for section!");
 
     // Check that contents are only things legal inside a virtual section.
@@ -630,7 +630,7 @@ void MCAssembler::Finish(MCObjectWriter *Writer) {
         continue;
 
       // Ignore virtual sections, they don't cause file size modifications.
-      if (getBackend().isVirtualSection(SD->getSection()))
+      if (SD->getSection().isVirtualSection())
         continue;
 
       // Otherwise, create a new align fragment at the end of the previous
diff --git a/llvm/lib/MC/MCSectionCOFF.cpp b/llvm/lib/MC/MCSectionCOFF.cpp
index 0909df42227..90091f06e9a 100644
--- a/llvm/lib/MC/MCSectionCOFF.cpp
+++ b/llvm/lib/MC/MCSectionCOFF.cpp
@@ -78,3 +78,7 @@ void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI,
 bool MCSectionCOFF::UseCodeAlign() const {
   return getKind().isText();
 }
+
+bool MCSectionCOFF::isVirtualSection() const {
+  return getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA;
+}
diff --git a/llvm/lib/MC/MCSectionELF.cpp b/llvm/lib/MC/MCSectionELF.cpp
index ab72a0ebf96..59568adf708 100644
--- a/llvm/lib/MC/MCSectionELF.cpp
+++ b/llvm/lib/MC/MCSectionELF.cpp
@@ -107,6 +107,10 @@ bool MCSectionELF::UseCodeAlign() const {
   return getFlags() & MCSectionELF::SHF_EXECINSTR;
 }
 
+bool MCSectionELF::isVirtualSection() const {
+  return getType() == MCSectionELF::SHT_NOBITS;
+}
+
 // HasCommonSymbols - True if this section holds common symbols, this is
 // indicated on the ELF object file by a symbol with SHN_COMMON section 
 // header index.
diff --git a/llvm/lib/MC/MCSectionMachO.cpp b/llvm/lib/MC/MCSectionMachO.cpp
index 0b74636d422..43268e63bbd 100644
--- a/llvm/lib/MC/MCSectionMachO.cpp
+++ b/llvm/lib/MC/MCSectionMachO.cpp
@@ -152,6 +152,12 @@ bool MCSectionMachO::UseCodeAlign() const {
   return hasAttribute(MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS);
 }
 
+bool MCSectionMachO::isVirtualSection() const {
+  return (getType() == MCSectionMachO::S_ZEROFILL ||
+          getType() == MCSectionMachO::S_GB_ZEROFILL ||
+          getType() == MCSectionMachO::S_THREAD_LOCAL_ZEROFILL);
+}
+
 /// StripSpaces - This removes leading and trailing spaces from the StringRef.
 static void StripSpaces(StringRef &Str) {
   while (!Str.empty() && isspace(Str[0]))
diff --git a/llvm/lib/MC/MachObjectWriter.cpp b/llvm/lib/MC/MachObjectWriter.cpp
index 41c11fba1d0..729a437b18f 100644
--- a/llvm/lib/MC/MachObjectWriter.cpp
+++ b/llvm/lib/MC/MachObjectWriter.cpp
@@ -371,7 +371,7 @@ public:
     uint64_t SectionSize = Layout.getSectionSize(&SD);
 
     // The offset is unused for virtual sections.
-    if (Asm.getBackend().isVirtualSection(SD.getSection())) {
+    if (SD.getSection().isVirtualSection()) {
       assert(Layout.getSectionFileSize(&SD) == 0 && "Invalid file size!");
       FileOffset = 0;
     }
@@ -1191,7 +1191,7 @@ public:
 
       VMSize = std::max(VMSize, Address + Size);
 
-      if (Asm.getBackend().isVirtualSection(SD.getSection()))
+      if (SD.getSection().isVirtualSection())
         continue;
 
       SectionDataSize = std::max(SectionDataSize, Address + Size);