[MC] Support symbolic expressions in assembly directives

This matches the behavior of GNU assembler which supports symbolic
expressions in absolute expressions used in assembly directives.

Differential Revision: http://reviews.llvm.org/D20656

llvm-svn: 271028

1 files changed, 14 insertions, 2 deletions

diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index 59bbc2e..9ed5a5f 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -135,9 +135,18 @@ void MCStreamer::EmitGPRel32Value(const MCExpr *Value) {
 /// EmitFill - Emit NumBytes bytes worth of the value specified by
 /// FillValue.  This implements directives such as '.space'.
 void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) {
-  const MCExpr *E = MCConstantExpr::create(FillValue, getContext());
   for (uint64_t i = 0, e = NumBytes; i != e; ++i)
-    EmitValue(E, 1);
+    EmitIntValue(FillValue, 1);
+}
+
+void MCStreamer::emitFill(uint64_t NumValues, int64_t Size, int64_t Expr) {
+  int64_t NonZeroSize = Size > 4 ? 4 : Size;
+  Expr &= ~0ULL >> (64 - NonZeroSize * 8);
+  for (uint64_t i = 0, e = NumValues; i != e; ++i) {
+    EmitIntValue(Expr, NonZeroSize);
+    if (NonZeroSize < Size)
+      EmitIntValue(0, Size - NonZeroSize);
+  }
 }
 
 /// The implementation in this class just redirects to EmitFill.
@@ -757,6 +766,9 @@ void MCStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) {
 }
 void MCStreamer::EmitULEB128Value(const MCExpr *Value) {}
 void MCStreamer::EmitSLEB128Value(const MCExpr *Value) {}
+void MCStreamer::emitFill(const MCExpr &NumBytes, uint64_t Value, SMLoc Loc) {}
+void MCStreamer::emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
+                          SMLoc Loc) {}
 void MCStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
                                       unsigned ValueSize,
                                       unsigned MaxBytesToEmit) {}