[PowerPC] [NFC] Create a helper function to copy register to particul…

…ar register class at PPCFastISel

Make copy register code as common function as following.

unsigned copyRegToRegClass(const TargetRegisterClass *ToRC, unsigned SrcReg, unsigned Flag = 0, unsigned SubReg = 0);

Differential Revision: https://reviews.llvm.org/D57368

llvm-svn: 352596

llvm/lib/Target/PowerPC/PPCFastISel.cpp

@@ -151,6 +151,14 @@ class PPCFastISel final : public FastISel {
     bool isVSSRCRegClass(const TargetRegisterClass *RC) const {
       return RC->getID() == PPC::VSSRCRegClassID;
     }
+    unsigned copyRegToRegClass(const TargetRegisterClass *ToRC,
+                               unsigned SrcReg, unsigned Flag = 0,
+                               unsigned SubReg = 0) {
+      unsigned TmpReg = createResultReg(ToRC);
+      BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
+              TII.get(TargetOpcode::COPY), TmpReg).addReg(SrcReg, Flag, SubReg);
+      return TmpReg;
+    }
     bool PPCEmitCmp(const Value *Src1Value, const Value *Src2Value,
                     bool isZExt, unsigned DestReg,
                     const PPC::Predicate Pred);
@@ -877,18 +885,10 @@ bool PPCFastISel::PPCEmitCmp(const Value *SrcValue1, const Value *SrcValue2,
         }
       } else {
         CmpOpc = PPC::FCMPUS;
-        if (isVSSRCRegClass(RC1)) {
-          unsigned TmpReg = createResultReg(&PPC::F4RCRegClass);
-          BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
-                  TII.get(TargetOpcode::COPY), TmpReg).addReg(SrcReg1);
-          SrcReg1 = TmpReg;
-        }
-        if (RC2 && isVSSRCRegClass(RC2)) {
-          unsigned TmpReg = createResultReg(&PPC::F4RCRegClass);
-          BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
-                  TII.get(TargetOpcode::COPY), TmpReg).addReg(SrcReg2);
-          SrcReg2 = TmpReg;
-        }
+        if (isVSSRCRegClass(RC1))
+          SrcReg1 = copyRegToRegClass(&PPC::F4RCRegClass, SrcReg1);
+        if (RC2 && isVSSRCRegClass(RC2))
+          SrcReg2 = copyRegToRegClass(&PPC::F4RCRegClass, SrcReg2);
       }
       break;
     case MVT::f64:
@@ -1210,13 +1210,8 @@ bool PPCFastISel::SelectFPToI(const Instruction *I, bool IsSigned) {
   // Convert f32 to f64 if necessary.  This is just a meaningless copy
   // to get the register class right.
   const TargetRegisterClass *InRC = MRI.getRegClass(SrcReg);
-  if (InRC == &PPC::F4RCRegClass) {
-    unsigned TmpReg = createResultReg(&PPC::F8RCRegClass);
-    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
-            TII.get(TargetOpcode::COPY), TmpReg)
-      .addReg(SrcReg);
-    SrcReg = TmpReg;
-  }
+  if (InRC == &PPC::F4RCRegClass)
+    SrcReg = copyRegToRegClass(&PPC::F8RCRegClass, SrcReg);
 
   // Determine the opcode for the conversion, which takes place
   // entirely within FPRs.
@@ -1510,11 +1505,7 @@ bool PPCFastISel::finishCall(MVT RetVT, CallLoweringInfo &CLI, unsigned &NumByte
 
     if (RetVT == CopyVT) {
       const TargetRegisterClass *CpyRC = TLI.getRegClassFor(CopyVT);
-      ResultReg = createResultReg(CpyRC);
-
-      BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
-              TII.get(TargetOpcode::COPY), ResultReg)
-        .addReg(SourcePhysReg);
+      ResultReg = copyRegToRegClass(CpyRC, SourcePhysReg);
 
     // If necessary, round the floating result to single precision.
     } else if (CopyVT == MVT::f64) {
@@ -1527,12 +1518,9 @@ bool PPCFastISel::finishCall(MVT RetVT, CallLoweringInfo &CLI, unsigned &NumByte
     // used along the fast-isel path (not lowered), and downstream logic
     // also doesn't like a direct subreg copy on a physical reg.)
     } else if (RetVT == MVT::i8 || RetVT == MVT::i16 || RetVT == MVT::i32) {
-      ResultReg = createResultReg(&PPC::GPRCRegClass);
       // Convert physical register from G8RC to GPRC.
       SourcePhysReg -= PPC::X0 - PPC::R0;
-      BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
-              TII.get(TargetOpcode::COPY), ResultReg)
-        .addReg(SourcePhysReg);
+      ResultReg = copyRegToRegClass(&PPC::GPRCRegClass, SourcePhysReg);
     }
 
     assert(ResultReg && "ResultReg unset!");
@@ -1884,13 +1872,8 @@ bool PPCFastISel::SelectTrunc(const Instruction *I) {
     return false;
 
   // The only interesting case is when we need to switch register classes.
-  if (SrcVT == MVT::i64) {
-    unsigned ResultReg = createResultReg(&PPC::GPRCRegClass);
-    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
-            TII.get(TargetOpcode::COPY),
-            ResultReg).addReg(SrcReg, 0, PPC::sub_32);
-    SrcReg = ResultReg;
-  }
+  if (SrcVT == MVT::i64)
+    SrcReg = copyRegToRegClass(&PPC::GPRCRegClass, SrcReg, 0, PPC::sub_32);
 
   updateValueMap(I, SrcReg);
   return true;