[PowerPC] Handle selection of compare instructions in fast-isel.

Mostly trivial patch adding support for compares.  The meat of the
work was added with the branch support.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189639 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 18 insertions, 0 deletions

diff --git a/lib/Target/PowerPC/PPCFastISel.cpp b/lib/Target/PowerPC/PPCFastISel.cpp
index 14a4b31710b4..aeda78bf6b9a 100644
--- a/lib/Target/PowerPC/PPCFastISel.cpp
+++ b/lib/Target/PowerPC/PPCFastISel.cpp
@@ -108,6 +108,7 @@ class PPCFastISel : public FastISel {
     bool SelectStore(const Instruction *I);
     bool SelectBranch(const Instruction *I);
     bool SelectIndirectBr(const Instruction *I);
+    bool SelectCmp(const Instruction *I);
     bool SelectBinaryIntOp(const Instruction *I, unsigned ISDOpcode);
     bool SelectRet(const Instruction *I);
     bool SelectIntExt(const Instruction *I);
@@ -1065,6 +1066,23 @@ bool PPCFastISel::SelectIndirectBr(const Instruction *I) {
   return true;
 }
 
+// Attempt to fast-select a compare instruction.
+bool PPCFastISel::SelectCmp(const Instruction *I) {
+  const CmpInst *CI = cast<CmpInst>(I);
+  Optional<PPC::Predicate> OptPPCPred = getComparePred(CI->getPredicate());
+  if (!OptPPCPred)
+    return false;
+
+  unsigned CondReg = createResultReg(&PPC::CRRCRegClass);
+
+  if (!PPCEmitCmp(CI->getOperand(0), CI->getOperand(1), CI->isUnsigned(),
+                  CondReg))
+    return false;
+
+  UpdateValueMap(I, CondReg);
+  return true;
+}
+
 // Attempt to fast-select an integer extend instruction.
 bool PPCFastISel::SelectIntExt(const Instruction *I) {
   Type *DestTy = I->getType();