Support: Simplify endian stream interface. NFCI.

Provide some free functions to reduce verbosity of endian-writing
a single value, and replace the endianness template parameter with
a field.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47032

llvm-svn: 332757

1 files changed, 4 insertions, 11 deletions

diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCCodeEmitter.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCCodeEmitter.cpp
index 92c8c224b71..2b948ca6002 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCCodeEmitter.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCCodeEmitter.cpp
@@ -122,25 +122,18 @@ public:
 
     // Output the constant in big/little endian byte order.
     unsigned Size = Desc.getSize();
+    support::endianness E = IsLittleEndian ? support::little : support::big;
     switch (Size) {
     case 0:
       break;
     case 4:
-      if (IsLittleEndian) {
-        support::endian::Writer<support::little>(OS).write<uint32_t>(Bits);
-      } else {
-        support::endian::Writer<support::big>(OS).write<uint32_t>(Bits);
-      }
+      support::endian::write<uint32_t>(OS, Bits, E);
       break;
     case 8:
       // If we emit a pair of instructions, the first one is
       // always in the top 32 bits, even on little-endian.
-      if (IsLittleEndian) {
-        uint64_t Swapped = (Bits << 32) | (Bits >> 32);
-        support::endian::Writer<support::little>(OS).write<uint64_t>(Swapped);
-      } else {
-        support::endian::Writer<support::big>(OS).write<uint64_t>(Bits);
-      }
+      support::endian::write<uint32_t>(OS, Bits >> 32, E);
+      support::endian::write<uint32_t>(OS, Bits, E);
       break;
     default:
       llvm_unreachable("Invalid instruction size");