[X86] Make the post machine scheduler macrofusion-aware.

Summary:
Given that X86 does not use this currently, this is an NFC. I'll
experiment with enabling and will report numbers.

Reviewers: andreadb, lebedev.ri

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60185

llvm-svn: 357568

1 files changed, 7 insertions, 0 deletions

diff --git a/llvm/lib/Target/X86/X86TargetMachine.cpp b/llvm/lib/Target/X86/X86TargetMachine.cpp
index b40b8b643ff..89c5d2d6628 100644
--- a/llvm/lib/Target/X86/X86TargetMachine.cpp
+++ b/llvm/lib/Target/X86/X86TargetMachine.cpp
@@ -355,6 +355,13 @@ public:
     return DAG;
   }
 
+  ScheduleDAGInstrs *
+  createPostMachineScheduler(MachineSchedContext *C) const override {
+    ScheduleDAGMI *DAG = createGenericSchedPostRA(C);
+    DAG->addMutation(createX86MacroFusionDAGMutation());
+    return DAG;
+  }
+
   void addIRPasses() override;
   bool addInstSelector() override;
   bool addIRTranslator() override;