PowerPC: Use CCBITRC operand for ISEL patterns.

This commit changes the ISEL patterns to use a CCBITRC operand
instead of a "pred" operand.  This matches the actual instruction
text more directly, and simplifies use of ISEL with the asm parser.
In addition, this change allows some simplification of handling
the "pred" operand, as this is now only used by BCC.

No change in generated code.

llvm-svn: 178003

llvm/lib/Target/PowerPC/InstPrinter/PPCInstPrinter.cpp

@@ -87,31 +87,6 @@ void PPCInstPrinter::printPredicateOperand(const MCInst *MI, unsigned OpNo,
                                            raw_ostream &O, 
                                            const char *Modifier) {
   unsigned Code = MI->getOperand(OpNo).getImm();
-  if (!Modifier) {
-    unsigned CCReg = MI->getOperand(OpNo+1).getReg();
-    unsigned RegNo;
-    switch (CCReg) {
-    default: llvm_unreachable("Unknown CR register");
-    case PPC::CR0: RegNo = 0; break;
-    case PPC::CR1: RegNo = 1; break;
-    case PPC::CR2: RegNo = 2; break;
-    case PPC::CR3: RegNo = 3; break;
-    case PPC::CR4: RegNo = 4; break;
-    case PPC::CR5: RegNo = 5; break;
-    case PPC::CR6: RegNo = 6; break;
-    case PPC::CR7: RegNo = 7; break;
-    }
-
-    // Print the CR bit number. The Code is ((BI << 5) | BO) for a
-    // BCC, but we must have the positive form here (BO == 12)
-    unsigned BI = Code >> 5;
-    assert((Code & 0xF) == 12 &&
-           "BO in predicate bit must have the positive form");
-
-    unsigned Value = 4*RegNo + BI;
-    O << Value;
-    return;
-  }
 
   if (StringRef(Modifier) == "cc") {
     switch ((PPC::Predicate)Code) {

llvm/lib/Target/PowerPC/PPCISelLowering.cpp

@@ -6170,24 +6170,24 @@ PPCTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
     unsigned SelectPred = MI->getOperand(4).getImm();
     DebugLoc dl = MI->getDebugLoc();
 
-    // The SelectPred is ((BI << 5) | BO) for a BCC
-    unsigned BO = SelectPred & 0xF;
-    assert((BO == 12 || BO == 4) && "invalid predicate BO field for isel");
-
-    unsigned TrueOpNo, FalseOpNo;
-    if (BO == 12) {
-      TrueOpNo = 2;
-      FalseOpNo = 3;
-    } else {
-      TrueOpNo = 3;
-      FalseOpNo = 2;
-      SelectPred = PPC::InvertPredicate((PPC::Predicate)SelectPred);
+    unsigned SubIdx;
+    bool SwapOps;
+    switch (SelectPred) {
+    default: llvm_unreachable("invalid predicate for isel");
+    case PPC::PRED_EQ: SubIdx = PPC::sub_eq; SwapOps = false; break;
+    case PPC::PRED_NE: SubIdx = PPC::sub_eq; SwapOps = true; break;
+    case PPC::PRED_LT: SubIdx = PPC::sub_lt; SwapOps = false; break;
+    case PPC::PRED_GE: SubIdx = PPC::sub_lt; SwapOps = true; break;
+    case PPC::PRED_GT: SubIdx = PPC::sub_gt; SwapOps = false; break;
+    case PPC::PRED_LE: SubIdx = PPC::sub_gt; SwapOps = true; break;
+    case PPC::PRED_UN: SubIdx = PPC::sub_un; SwapOps = false; break;
+    case PPC::PRED_NU: SubIdx = PPC::sub_un; SwapOps = true; break;
     }
 
     BuildMI(*BB, MI, dl, TII->get(OpCode), MI->getOperand(0).getReg())
-      .addReg(MI->getOperand(TrueOpNo).getReg())
-      .addReg(MI->getOperand(FalseOpNo).getReg())
-      .addImm(SelectPred).addReg(MI->getOperand(1).getReg());
+      .addReg(MI->getOperand(SwapOps? 3 : 2).getReg())
+      .addReg(MI->getOperand(SwapOps? 2 : 3).getReg())
+      .addReg(MI->getOperand(1).getReg(), 0, SubIdx);
   } else if (MI->getOpcode() == PPC::SELECT_CC_I4 ||
              MI->getOpcode() == PPC::SELECT_CC_I8 ||
              MI->getOpcode() == PPC::SELECT_CC_F4 ||

llvm/lib/Target/PowerPC/PPCInstr64Bit.td

@@ -514,7 +514,7 @@ def RLWINM8 : MForm_2<21,
                      []>;
 
 def ISEL8   : AForm_4<31, 15,
-                     (outs G8RC:$rT), (ins G8RC_NOX0:$rA, G8RC:$rB, pred:$cond),
+                     (outs G8RC:$rT), (ins G8RC_NOX0:$rA, G8RC:$rB, CRBITRC:$cond),
                      "isel $rT, $rA, $rB, $cond", IntGeneral,
                      []>;
 }  // End FXU Operations.

llvm/lib/Target/PowerPC/PPCInstrFormats.td

@@ -777,16 +777,14 @@ class AForm_4<bits<6> opcode, bits<5> xo, dag OOL, dag IOL, string asmstr,
   bits<5> RT;
   bits<5> RA;
   bits<5> RB;
-  bits<7> BIBO;  // 2 bits of BI and 5 bits of BO (must be 12).
-  bits<3> CR;
+  bits<5> COND;
 
   let Pattern = pattern;
 
   let Inst{6-10}  = RT;
   let Inst{11-15} = RA;
   let Inst{16-20} = RB;
-  let Inst{21-23} = CR;
-  let Inst{24-25} = BIBO{6-5};
+  let Inst{21-25} = COND;
   let Inst{26-30} = xo;
   let Inst{31}    = 0;
 }

llvm/lib/Target/PowerPC/PPCInstrInfo.td

@@ -1482,7 +1482,7 @@ let Uses = [RM] in {
 
 let PPC970_Unit = 1 in {  // FXU Operations.
   def ISEL  : AForm_4<31, 15,
-                     (outs GPRC:$rT), (ins GPRC_NOR0:$rA, GPRC:$rB, pred:$cond),
+                     (outs GPRC:$rT), (ins GPRC_NOR0:$rA, GPRC:$rB, CRBITRC:$cond),
                      "isel $rT, $rA, $rB, $cond", IntGeneral,
                      []>;
 }