TableGen: Optimize common string concatenation with SmallString
llvm-svn: 288611
diff --git a/llvm/lib/TableGen/Record.cpp b/llvm/lib/TableGen/Record.cpp
index 3e1be83..a82c381 100644
--- a/llvm/lib/TableGen/Record.cpp
+++ b/llvm/lib/TableGen/Record.cpp
@@ -15,6 +15,7 @@
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringMap.h"
@@ -839,8 +840,12 @@
case STRCONCAT: {
StringInit *LHSs = dyn_cast<StringInit>(LHS);
StringInit *RHSs = dyn_cast<StringInit>(RHS);
- if (LHSs && RHSs)
- return StringInit::get(LHSs->getValue() + RHSs->getValue());
+ if (LHSs && RHSs) {
+ // STRCONCAT is common; Use a SmallString to avoid most heap allocations.
+ SmallString<80> Concat(LHSs->getValue());
+ Concat.append(RHSs->getValue());
+ return StringInit::get(Concat);
+ }
break;
}
case EQ: {