[llvm-commits] [llvm] r85044 - /llvm/trunk/include/llvm/Target/TargetInstrInfo.h

[Evan Cheng]

Author: evancheng
Date: Sun Oct 25 02:47:07 2009
New Revision: 85044

URL: http://llvm.org/viewvc/llvm-project?rev=85044&view=rev
Log:
Add isIdentityCopy to check for identity copy (or extract_subreg, etc.)

Modified:
    llvm/trunk/include/llvm/Target/TargetInstrInfo.h

Modified: llvm/trunk/include/llvm/Target/TargetInstrInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetInstrInfo.h?rev=85044&r1=85043&r2=85044&view=diff

==============================================================================
--- llvm/trunk/include/llvm/Target/TargetInstrInfo.h (original)
+++ llvm/trunk/include/llvm/Target/TargetInstrInfo.h Sun Oct 25 02:47:07 2009
@@ -145,20 +145,30 @@
   /// isIdentityCopy - Return true if the instruction is a copy (or
   /// extract_subreg, insert_subreg, subreg_to_reg) where the source and
   /// destination registers are the same.
-  bool isIdentityCopy(const MachineInstr &MI) const {
-    unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
+  bool isIdentityCopy(const MachineInstr &MI,
+                      unsigned &SrcReg, unsigned &DstReg,
+                      unsigned &SrcSubIdx, unsigned &DstSubIdx) const {
     if (isMoveInstr(MI, SrcReg, DstReg, SrcSubIdx, DstSubIdx) &&
         SrcReg == DstReg)
       return true;
 
-    if (MI.getOpcode() == TargetInstrInfo::EXTRACT_SUBREG &&
-        MI.getOperand(0).getReg() == MI.getOperand(1).getReg())
-    return true;
+    if (MI.getOpcode() == TargetInstrInfo::EXTRACT_SUBREG) {
+      DstReg = MI.getOperand(0).getReg();
+      DstSubIdx = MI.getOperand(0).getSubReg();
+      SrcReg = MI.getOperand(1).getReg();
+      SrcSubIdx = MI.getOperand(1).getSubReg();
+      return DstReg == SrcReg;
+    }
+
+    if (MI.getOpcode() == TargetInstrInfo::INSERT_SUBREG ||
+        MI.getOpcode() == TargetInstrInfo::SUBREG_TO_REG) {
+      DstReg = MI.getOperand(0).getReg();
+      DstSubIdx = MI.getOperand(0).getSubReg();
+      SrcReg = MI.getOperand(2).getReg();
+      SrcSubIdx = MI.getOperand(2).getSubReg();
+      return DstReg == SrcReg;
+    }
 
-    if ((MI.getOpcode() == TargetInstrInfo::INSERT_SUBREG ||
-         MI.getOpcode() == TargetInstrInfo::SUBREG_TO_REG) &&
-        MI.getOperand(0).getReg() == MI.getOperand(2).getReg())
-      return true;
     return false;
   }