Minor optimization: when doing eq/ne comparions and RHS is a constant - swap operands...

[oota-llvm.git] / lib / Target / MSP430 / MSP430ISelLowering.cpp

diff --git a/lib/Target/MSP430/MSP430ISelLowering.cpp b/lib/Target/MSP430/MSP430ISelLowering.cpp
index 47a977798da9a438acd3dac69c7133a809be187b..29cc370bef99020770a6f5e9de572e894ceaa41b 100644 (file)
--- a/lib/Target/MSP430/MSP430ISelLowering.cpp
+++ b/lib/Target/MSP430/MSP430ISelLowering.cpp
@@ -62,7 +62,7 @@ MSP430TargetLowering::MSP430TargetLowering(MSP430TargetMachine &tm) :
   setBooleanContents(ZeroOrOneBooleanContent);
   setSchedulingPreference(SchedulingForLatency);
 
-  // We have post-incremented loads / stores
+  // We have post-incremented loads / stores.
   setIndexedLoadAction(ISD::POST_INC, MVT::i8, Legal);
   setIndexedLoadAction(ISD::POST_INC, MVT::i16, Legal);
 
@@ -162,7 +162,7 @@ SDValue MSP430TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) {
 
 /// getFunctionAlignment - Return the Log2 alignment of this function.
 unsigned MSP430TargetLowering::getFunctionAlignment(const Function *F) const {
-  return F->hasFnAttr(Attribute::OptimizeForSize) ? 1 : 4;
+  return F->hasFnAttr(Attribute::OptimizeForSize) ? 1 : 2;
 }
 
 //===----------------------------------------------------------------------===//
@@ -318,7 +318,7 @@ MSP430TargetLowering::LowerCCCArguments(SDValue Chain,
              << "\n";
       }
       // Create the frame index object for this incoming parameter...
-      int FI = MFI->CreateFixedObject(ObjSize, VA.getLocMemOffset());
+      int FI = MFI->CreateFixedObject(ObjSize, VA.getLocMemOffset(), true, false);
 
       // Create the SelectionDAG nodes corresponding to a load
       //from this parameter
@@ -594,9 +594,17 @@ static SDValue EmitCMP(SDValue &LHS, SDValue &RHS, SDValue &TargetCC,
   default: llvm_unreachable("Invalid integer condition!");
   case ISD::SETEQ:
     TCC = MSP430CC::COND_E;     // aka COND_Z
+    // Minor optimization: if RHS is a constant, swap operands, then the
+    // constant can be folded into comparison.
+    if (RHS.getOpcode() == ISD::Constant)
+      std::swap(LHS, RHS);
     break;
   case ISD::SETNE:
     TCC = MSP430CC::COND_NE;    // aka COND_NZ
+    // Minor optimization: if RHS is a constant, swap operands, then the
+    // constant can be folded into comparison.
+    if (RHS.getOpcode() == ISD::Constant)
+      std::swap(LHS, RHS);
     break;
   case ISD::SETULE:
     std::swap(LHS, RHS);        // FALLTHROUGH