[MC] Teach the MachO object writer about N_FUNC_COLD
N_FUNC_COLD is a new MachO symbol attribute. It's a hint to the linker
to order a symbol towards the end of its section, to improve locality.
Example:
```
void a1() {}
__attribute__((cold)) void a2() {}
void a3() {}
int main() {
a1();
a2();
a3();
return 0;
}
```
A linker that supports N_FUNC_COLD will order _a2 to the end of the text
section. From `nm -njU` output, we see:
```
_a1
_a3
_main
_a2
```
Differential Revision: https://reviews.llvm.org/D57190
llvm-svn: 352227
diff --git a/llvm/lib/MC/MCELFStreamer.cpp b/llvm/lib/MC/MCELFStreamer.cpp
index 6954692..6fe16abd 100644
--- a/llvm/lib/MC/MCELFStreamer.cpp
+++ b/llvm/lib/MC/MCELFStreamer.cpp
@@ -201,6 +201,7 @@
// In the future it might be worth trying to make these operations more well
// defined.
switch (Attribute) {
+ case MCSA_Cold:
case MCSA_LazyReference:
case MCSA_Reference:
case MCSA_SymbolResolver: