Add a subtarget hook: enablePostMachineScheduler.

As requested by AArch64 subtargets.

Note that this will have no effect until the
AArch64 target actually enables the pass like this:
substitutePass(&PostRASchedulerID, &PostMachineSchedulerID);

As soon as armv7 switches over, PostMachineScheduler will become the
default postRA scheduler, so this won't be necessary any more.
Targets using the old postRA schedule would then do:
substitutePass(&PostMachineSchedulerID, &PostRASchedulerID);

llvm-svn: 210167

3 files changed, 14 insertions, 0 deletions

diff --git a/llvm/lib/Target/ARM/ARMSubtarget.cpp b/llvm/lib/Target/ARM/ARMSubtarget.cpp
index 1c9dd4d49d6..61c00b5930c 100644
--- a/llvm/lib/Target/ARM/ARMSubtarget.cpp
+++ b/llvm/lib/Target/ARM/ARMSubtarget.cpp
@@ -352,6 +352,13 @@ bool ARMSubtarget::hasSinCos() const {
     !getTargetTriple().isOSVersionLT(7, 0);
 }
 
+// Enable the PostMachineScheduler if the target selects it instead of
+// PostRAScheduler. Currently only available on the command line via
+// -misched-postra.
+bool ARMSubtarget::enablePostMachineScheduler() const {
+  return PostRAScheduler;
+}
+
 bool ARMSubtarget::enablePostRAScheduler(
            CodeGenOpt::Level OptLevel,
            TargetSubtargetInfo::AntiDepBreakMode& Mode,
diff --git a/llvm/lib/Target/ARM/ARMSubtarget.h b/llvm/lib/Target/ARM/ARMSubtarget.h
index fd106f6fc86..2694c34293a 100644
--- a/llvm/lib/Target/ARM/ARMSubtarget.h
+++ b/llvm/lib/Target/ARM/ARMSubtarget.h
@@ -396,6 +396,9 @@ public:
   /// compiler runtime or math libraries.
   bool hasSinCos() const;
 
+  /// True for some subtargets at > -O0.
+  bool enablePostMachineScheduler() const;
+
   /// enablePostRAScheduler - True at 'More' optimization.
   bool enablePostRAScheduler(CodeGenOpt::Level OptLevel,
                              TargetSubtargetInfo::AntiDepBreakMode& Mode,
diff --git a/llvm/lib/Target/TargetSubtargetInfo.cpp b/llvm/lib/Target/TargetSubtargetInfo.cpp
index 3ca13dac035..0c388f8fb26 100644
--- a/llvm/lib/Target/TargetSubtargetInfo.cpp
+++ b/llvm/lib/Target/TargetSubtargetInfo.cpp
@@ -43,6 +43,10 @@ bool TargetSubtargetInfo::enableMachineScheduler() const {
   return false;
 }
 
+bool TargetSubtargetInfo::enablePostMachineScheduler() const {
+  return false;
+}
+
 bool TargetSubtargetInfo::enablePostRAScheduler(
           CodeGenOpt::Level OptLevel,
           AntiDepBreakMode& Mode,