[llvm-commits] [llvm] r152243 - /llvm/trunk/lib/Target/ARM/ARMFastISel.cpp

[Chad Rosier]

Author: mcrosier
Date: Wed Mar  7 14:59:26 2012
New Revision: 152243

URL: http://llvm.org/viewvc/llvm-project?rev=152243&view=rev
Log:
[fast-isel] ARMEmitCmp generates FMSTAT, which transfers the floating-point 
condition flags to CPSR.  This allows us to simplify SelectCmp.
Patch by Zonr Chang <zonr.xchg at gmail.com>.

Modified:
    llvm/trunk/lib/Target/ARM/ARMFastISel.cpp

Modified: llvm/trunk/lib/Target/ARM/ARMFastISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMFastISel.cpp?rev=152243&r1=152242&r2=152243&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMFastISel.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMFastISel.cpp Wed Mar  7 14:59:26 2012
@@ -1475,7 +1475,6 @@
 
 bool ARMFastISel::SelectCmp(const Instruction *I) {
   const CmpInst *CI = cast<CmpInst>(I);
-  Type *Ty = CI->getOperand(0)->getType();
 
   // Get the compare predicate.
   ARMCC::CondCodes ARMPred = getComparePred(CI->getPredicate());
@@ -1495,11 +1494,10 @@
   unsigned DestReg = createResultReg(RC);
   Constant *Zero = ConstantInt::get(Type::getInt32Ty(*Context), 0);
   unsigned ZeroReg = TargetMaterializeConstant(Zero);
-  bool isFloat = (Ty->isFloatTy() || Ty->isDoubleTy());
-  unsigned CondReg = isFloat ? ARM::FPSCR_NZCV : ARM::CPSR;
+  // ARMEmitCmp emits a FMSTAT when necessary, so it's always safe to use CPSR.
   BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(MovCCOpc), DestReg)
           .addReg(ZeroReg).addImm(1)
-          .addImm(ARMPred).addReg(CondReg);
+          .addImm(ARMPred).addReg(ARM::CPSR);
 
   UpdateValueMap(I, DestReg);
   return true;