[lli/COFF] Set the correct alignment for common symbols

Otherwise we set it always to zero, which is not correct,
and we assert inside alignTo (Assertion failed:
Align != 0u && "Align can't be 0.").

Differential Revision:  https://reviews.llvm.org/D26173

llvm-svn: 285841

1 files changed, 9 insertions, 0 deletions

diff --git a/llvm/lib/Object/COFFObjectFile.cpp b/llvm/lib/Object/COFFObjectFile.cpp
index 601a7faba32..c95037f4540 100644
--- a/llvm/lib/Object/COFFObjectFile.cpp
+++ b/llvm/lib/Object/COFFObjectFile.cpp
@@ -157,6 +157,15 @@ uint64_t COFFObjectFile::getSymbolValueImpl(DataRefImpl Ref) const {
   return getCOFFSymbol(Ref).getValue();
 }
 
+uint32_t COFFObjectFile::getSymbolAlignment(DataRefImpl Ref) const {
+  // MSVC/link.exe seems to align symbols to the next-power-of-2
+  // up to 32 bytes.
+  COFFSymbolRef Symb = getCOFFSymbol(Ref);
+  uint32_t Value = Symb.getValue();
+  return std::min(uint64_t(32),
+                  isPowerOf2_64(Value) ? Value : NextPowerOf2(Value));
+}
+
 Expected<uint64_t> COFFObjectFile::getSymbolAddress(DataRefImpl Ref) const {
   uint64_t Result = getSymbolValue(Ref);
   COFFSymbolRef Symb = getCOFFSymbol(Ref);