[llvm-commits] [llvm] r89574 - /llvm/trunk/lib/Target/MSP430/MSP430ISelLowering.cpp

[Anton Korobeynikov]

Author: asl
Date: Sat Nov 21 19:14:08 2009
New Revision: 89574

URL: http://llvm.org/viewvc/llvm-project?rev=89574&view=rev
Log:
Minor optimization: when doing eq/ne comparions and RHS is a constant - swap operands, this will allow us to fold imm into comparison.

Modified:
    llvm/trunk/lib/Target/MSP430/MSP430ISelLowering.cpp

Modified: llvm/trunk/lib/Target/MSP430/MSP430ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/MSP430/MSP430ISelLowering.cpp?rev=89574&r1=89573&r2=89574&view=diff

==============================================================================
--- llvm/trunk/lib/Target/MSP430/MSP430ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/MSP430/MSP430ISelLowering.cpp Sat Nov 21 19:14:08 2009
@@ -594,9 +594,17 @@
   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