malloc elimination: it's a bad idea to use raw_svector_ostream on a

small heap-allocated SmallString because it unconditionally forces a malloc.

(Revised version of r129688, with the necessary flush() call.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129716 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/MC/MCObjectStreamer.cpp b/lib/MC/MCObjectStreamer.cpp
index ef22eaaaa49836016cbaf1758d5def219c3a8cac..bd7de5739ad08ec4341d281e632a55d896d27b20 100644 (file)
--- a/lib/MC/MCObjectStreamer.cpp
+++ b/lib/MC/MCObjectStreamer.cpp
@@ -191,8 +191,11 @@ void MCObjectStreamer::EmitInstruction(const MCInst &Inst) {
 void MCObjectStreamer::EmitInstToFragment(const MCInst &Inst) {
   MCInstFragment *IF = new MCInstFragment(Inst, getCurrentSectionData());
 
-  raw_svector_ostream VecOS(IF->getCode());
+  SmallString<128> Code;
+  raw_svector_ostream VecOS(Code);
   getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, IF->getFixups());
+  VecOS.flush();
+  IF->getCode().append(Code.begin(), Code.end());
 }
 
 static const MCExpr *BuildSymbolDiff(MCContext &Context,