Allow targets to specify a minimum supported NOP size when performing NOP padding. If the desired padding is smaller than the supported NOP size,

we will enlarge the padding to make it work.

llvm-svn: 162870

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp
index 05519b56ffe..c872bd62c9a 100644
--- a/llvm/lib/MC/MCAssembler.cpp
+++ b/llvm/lib/MC/MCAssembler.cpp
@@ -325,6 +325,12 @@ uint64_t MCAssembler::computeFragmentSize(const MCAsmLayout &Layout,
     const MCAlignFragment &AF = cast<MCAlignFragment>(F);
     unsigned Offset = Layout.getFragmentOffset(&AF);
     unsigned Size = OffsetToAlignment(Offset, AF.getAlignment());
+    // If we are padding with nops, force the padding to be larger than the
+    // minimum nop size.
+    if (Size > 0 && AF.hasEmitNops()) {
+      while (Size % getBackend().getMinimumNopSize())
+        Size += AF.getAlignment();
+    }
     if (Size > AF.getMaxBytesToEmit())
       return 0;
     return Size;