[PowerPC] Implement PPCTargetLowering::getTgtMemIntrinsic

This implements PPCTargetLowering::getTgtMemIntrinsic for Altivec load/store
intrinsics. As with the construction of the MachineMemOperands for the
intrinsic calls used for unaligned load/store lowering, the only slight
complication is that we need to represent a larger memory range than the
loaded/stored value-type size (because the address is rounded down to an
aligned address, and we need to conservatively represent the entire possible
range of the actual access). This required adding an extra size field to
TargetLowering::IntrinsicInfo, and this was done in a way that required no
modifications to other targets (the size defaults to the store size of the
provided memory data type).

This fixes test/CodeGen/PowerPC/unal-altivec-wint.ll (so it can be un-XFAILed).

llvm-svn: 215512
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 085318c..8d28d79 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -9206,6 +9206,82 @@
   return false;
 }
 
+bool PPCTargetLowering::getTgtMemIntrinsic(IntrinsicInfo &Info,
+                                           const CallInst &I,
+                                           unsigned Intrinsic) const {
+
+  switch (Intrinsic) {
+  case Intrinsic::ppc_altivec_lvx:
+  case Intrinsic::ppc_altivec_lvxl:
+  case Intrinsic::ppc_altivec_lvebx:
+  case Intrinsic::ppc_altivec_lvehx:
+  case Intrinsic::ppc_altivec_lvewx: {
+    EVT VT;
+    switch (Intrinsic) {
+    case Intrinsic::ppc_altivec_lvebx:
+      VT = MVT::i8;
+      break;
+    case Intrinsic::ppc_altivec_lvehx:
+      VT = MVT::i16;
+      break;
+    case Intrinsic::ppc_altivec_lvewx:
+      VT = MVT::i32;
+      break;
+    default:
+      VT = MVT::v4i32;
+      break;
+    }
+
+    Info.opc = ISD::INTRINSIC_W_CHAIN;
+    Info.memVT = VT;
+    Info.ptrVal = I.getArgOperand(0);
+    Info.offset = -VT.getStoreSize()+1;
+    Info.size = 2*VT.getStoreSize()-1;
+    Info.align = 1;
+    Info.vol = false;
+    Info.readMem = true;
+    Info.writeMem = false;
+    return true;
+  }
+  case Intrinsic::ppc_altivec_stvx:
+  case Intrinsic::ppc_altivec_stvxl:
+  case Intrinsic::ppc_altivec_stvebx:
+  case Intrinsic::ppc_altivec_stvehx:
+  case Intrinsic::ppc_altivec_stvewx: {
+    EVT VT;
+    switch (Intrinsic) {
+    case Intrinsic::ppc_altivec_stvebx:
+      VT = MVT::i8;
+      break;
+    case Intrinsic::ppc_altivec_stvehx:
+      VT = MVT::i16;
+      break;
+    case Intrinsic::ppc_altivec_stvewx:
+      VT = MVT::i32;
+      break;
+    default:
+      VT = MVT::v4i32;
+      break;
+    }
+
+    Info.opc = ISD::INTRINSIC_VOID;
+    Info.memVT = VT;
+    Info.ptrVal = I.getArgOperand(1);
+    Info.offset = -VT.getStoreSize()+1;
+    Info.size = 2*VT.getStoreSize()-1;
+    Info.align = 1;
+    Info.vol = false;
+    Info.readMem = false;
+    Info.writeMem = true;
+    return true;
+  }
+  default:
+    break;
+  }
+
+  return false;
+}
+
 /// getOptimalMemOpType - Returns the target specific optimal type for load
 /// and store operations as a result of memset, memcpy, and memmove
 /// lowering. If DstAlign is zero that means it's safe to destination