[ARM] Define a subtarget feature and use it to decide whether long calls should

be emitted.

This is needed to enable ARM long calls for LTO and enable and disable it on a
per-function basis.

Out-of-tree projects currently using EnableARMLongCalls to emit long calls
should start passing "+long-calls" to the feature string (see the changes made
to clang in r241565).

rdar://problem/21529937

Differential Revision: http://reviews.llvm.org/D9364

llvm-svn: 241566

1 files changed, 1 insertions, 0 deletions

diff --git a/llvm/lib/Target/ARM/ARMSubtarget.cpp b/llvm/lib/Target/ARM/ARMSubtarget.cpp
index af18eeabf0e..fe9743d09b5 100644
--- a/llvm/lib/Target/ARM/ARMSubtarget.cpp
+++ b/llvm/lib/Target/ARM/ARMSubtarget.cpp
@@ -172,6 +172,7 @@ void ARMSubtarget::initializeEnvironment() {
   AllowsUnalignedMem = false;
   Thumb2DSP = false;
   UseNaClTrap = false;
+  GenLongCalls = false;
   UnsafeFPMath = false;
 }