[llvm-commits] [llvm] r118192 - /llvm/trunk/lib/Target/ARM/ARMFastISel.cpp

[Eric Christopher]

Author: echristo
Date: Wed Nov  3 15:21:17 2010
New Revision: 118192

URL: http://llvm.org/viewvc/llvm-project?rev=118192&view=rev
Log:
Optimize generated code for integer materialization a bit.

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=118192&r1=118191&r2=118192&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMFastISel.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMFastISel.cpp Wed Nov  3 15:21:17 2010
@@ -434,6 +434,19 @@
   // For now 32-bit only.
   if (VT != MVT::i32) return false;
 
+  unsigned DestReg = createResultReg(TLI.getRegClassFor(VT));
+
+  // If we can do this in a single instruction without a constant pool entry
+  // do so now.
+  const ConstantInt *CI = cast<ConstantInt>(C);
+  if (isUInt<16>(CI->getSExtValue())) {
+    unsigned Opc = isThumb ? ARM::t2MOVi16 : ARM::MOVi16;
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+			    TII.get(Opc), DestReg)
+		    .addImm(CI->getSExtValue()));
+    return DestReg;
+  }
+
   // MachineConstantPool wants an explicit alignment.
   unsigned Align = TD.getPrefTypeAlignment(C->getType());
   if (Align == 0) {
@@ -441,7 +454,6 @@
     Align = TD.getTypeAllocSize(C->getType());
   }
   unsigned Idx = MCP.getConstantPoolIndex(C, Align);
-  unsigned DestReg = createResultReg(TLI.getRegClassFor(VT));
 
   if (isThumb)
     AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,