From 352a2fa1e765943fde9d622313a0977fe2c3a607 Mon Sep 17 00:00:00 2001
From: "Diogo N. Sampaio" <diogo.sampaio@arm.com>
Date: Thu, 11 Oct 2018 14:10:32 +0000
Subject: [PATCH] [AARCH64][FIX] Emit data symbol for constant pool data

The ARM64 elf emitter would omit printing data
symbol for zero filled constant data. This patch
overrides the emitFill method as to enforce that
the symbol is correctly printed.

Differential revision: https://reviews.llvm.org/D53132

llvm-svn: 344248
---
 .../AArch64/MCTargetDesc/AArch64ELFStreamer.cpp   |  5 +++++
 llvm/test/MC/AArch64/CheckDataSymbol.s            | 15 +++++++++++++++
 2 files changed, 20 insertions(+)
 create mode 100644 llvm/test/MC/AArch64/CheckDataSymbol.s

diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
index c0ef8b670286..a09ac6b94c17 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
@@ -154,6 +154,11 @@ public:
     MCELFStreamer::EmitValueImpl(Value, Size, Loc);
   }
 
+  void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
+                                  SMLoc Loc) override {
+    EmitDataMappingSymbol();
+    MCObjectStreamer::emitFill(NumBytes, FillValue, Loc);
+  }
 private:
   enum ElfMappingSymbol {
     EMS_None,
diff --git a/llvm/test/MC/AArch64/CheckDataSymbol.s b/llvm/test/MC/AArch64/CheckDataSymbol.s
new file mode 100644
index 000000000000..ea3ed7b28732
--- /dev/null
+++ b/llvm/test/MC/AArch64/CheckDataSymbol.s
@@ -0,0 +1,15 @@
+# RUN: llvm-mc -filetype=obj -assemble \
+# RUN: -triple=aarch64- %s -o - \
+# RUN: | llvm-readobj -s -t - | FileCheck %s
+# CHECK:     Name: $d.1 ({{[1-9][0-9]+}})
+# CHECK-NEXT:     Value: 0x4
+# CHECK-NEXT:     Size: 0
+# CHECK-NEXT:     Binding: Local (0x0)
+# CHECK-NEXT:     Type: None (0x0)
+# CHECK-NEXT:     Other: 0
+# CHECK-NEXT:     Section: .text (0x2)
+# CHECK-NEXT:   }
+
+.text
+nop
+.zero 4