MC: Add MCAlignFragment::OnlyAlignAddress bit. This is a bit of magic that says the align fragment shouldn't contribute to the logical section size, it is will be used for cleaning up the code to handle section alignment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103690 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp
index ced395c..8086b3d 100644
--- a/lib/MC/MCAssembler.cpp
+++ b/lib/MC/MCAssembler.cpp
@@ -392,6 +392,9 @@
case MCFragment::FT_Align: {
MCAlignFragment &AF = cast<MCAlignFragment>(F);
+ assert((!AF.hasOnlyAlignAddress() || !AF.getNextNode()) &&
+ "Invalid OnlyAlignAddress bit, not the last fragment!");
+
EffectiveSize = OffsetToAlignment(Address, AF.getAlignment());
if (EffectiveSize > AF.getMaxBytesToEmit())
EffectiveSize = 0;
@@ -474,9 +477,18 @@
MCFragment *F = &SD.getFragmentList().back();
Size = Layout.getFragmentOffset(F) + Layout.getFragmentEffectiveSize(F);
}
- Layout.setSectionSize(&SD, Size);
Layout.setSectionAddressSize(&SD, Size);
Layout.setSectionFileSize(&SD, IsVirtual ? 0 : Size);
+
+ // Handle OnlyAlignAddress bit.
+ if (!SD.getFragmentList().empty()) {
+ MCAlignFragment *AF =
+ dyn_cast<MCAlignFragment>(&SD.getFragmentList().back());
+ if (AF && AF->hasOnlyAlignAddress())
+ Size -= Layout.getFragmentEffectiveSize(AF);
+ }
+
+ Layout.setSectionSize(&SD, Size);
}
/// WriteFragmentData - Write the \arg F data to the output file.
@@ -856,6 +868,10 @@
OS << "<MCAlignFragment ";
this->MCFragment::dump();
+ if (hasEmitNops())
+ OS << " (emit nops)";
+ if (hasOnlyAlignAddress())
+ OS << " (only align section)";
OS << "\n ";
OS << " Alignment:" << getAlignment()
<< " Value:" << getValue() << " ValueSize:" << getValueSize()