Enable ILP scheduling for all nodes by default on PPC.

Over the entire test-suite, this has an insignificantly negative average
performance impact, but reduces some of the worst slowdowns from the
anti-dep. change (r158294).

Largest speedups:
SingleSource/Benchmarks/Stanford/Quicksort - 28%
SingleSource/Benchmarks/Stanford/Towers - 24%
SingleSource/Benchmarks/Shootout-C++/matrix - 23%
MultiSource/Benchmarks/SciMark2-C/scimark2 - 19%
MultiSource/Benchmarks/MiBench/automotive-bitcount/automotive-bitcount - 15%
(matrix and automotive-bitcount were both in the top-5 slowdown list from the
anti-dep. change)

Largest slowdowns:
MultiSource/Benchmarks/McCat/03-testtrie/testtrie - 28%
MultiSource/Benchmarks/mediabench/gsm/toast/toast - 26%
MultiSource/Benchmarks/MiBench/automotive-susan/automotive-susan - 21%
SingleSource/Benchmarks/CoyoteBench/lpbench - 20%
MultiSource/Applications/d/make_dparser - 16%

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158296 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 4 deletions

diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index c0d75b237c..964d5a0d94 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -54,6 +54,9 @@ static bool CC_PPC_SVR4_Custom_AlignFPArgRegs(unsigned &ValNo, MVT &ValVT,
 static cl::opt<bool> DisablePPCPreinc("disable-ppc-preinc",
 cl::desc("disable preincrement load/store generation on PPC"), cl::Hidden);
 
+static cl::opt<bool> DisableILPPref("disable-ppc-ilp-pref",
+cl::desc("disable setting the node scheduling preference to ILP on PPC"), cl::Hidden);
+
 static TargetLoweringObjectFile *CreateTLOF(const PPCTargetMachine &TM) {
   if (TM.getSubtargetImpl()->isDarwin())
     return new TargetLoweringObjectFileMachO();
@@ -5871,10 +5874,9 @@ EVT PPCTargetLowering::getOptimalMemOpType(uint64_t Size,
 }
 
 Sched::Preference PPCTargetLowering::getSchedulingPreference(SDNode *N) const {
-  unsigned Directive = PPCSubTarget.getDarwinDirective();
-  if (Directive == PPC::DIR_440 || Directive == PPC::DIR_A2)
-    return Sched::ILP;
+  if (DisableILPPref)
+    return TargetLowering::getSchedulingPreference(N);
 
-  return TargetLowering::getSchedulingPreference(N);
+  return Sched::ILP;
 }