[PPC] Add intrinsic mapping to the xscvhpsp instruction

add an intrinsic to expose the 'VSX Scalar Convert Half-Precision to
Single-Precision' instruction.

Differential review: https://reviews.llvm.org/D26536

llvm-svn: 286862

llvm/include/llvm/IR/IntrinsicsPowerPC.td

@@ -867,6 +867,9 @@ def int_ppc_vsx_xvtstdcdp :
 def int_ppc_vsx_xvtstdcsp :
       PowerPC_VSX_Intrinsic<"xvtstdcsp", [llvm_v4i32_ty],
                             [llvm_v4f32_ty,llvm_i32_ty], [IntrNoMem]>;
+def int_ppc_vsx_xvcvhpsp :
+      PowerPC_VSX_Intrinsic<"xvcvhpsp", [llvm_v4f32_ty],
+                            [llvm_v8i16_ty],[IntrNoMem]>;
 }
 
 //===----------------------------------------------------------------------===//

llvm/lib/Target/PowerPC/PPCInstrVSX.td

@@ -2132,6 +2132,7 @@ let AddedComplexity = 400, Predicates = [HasP9Vector] in {
   def XSCVSDQP  : X_VT5_XO5_VB5_TyVB<63, 10, 836, "xscvsdqp", vfrc, []>;
   def XSCVUDQP  : X_VT5_XO5_VB5_TyVB<63,  2, 836, "xscvudqp", vfrc, []>;
 
+  let UseVSXReg = 1 in {
   //===--------------------------------------------------------------------===//
   // Round to Floating-Point Integer Instructions
 
@@ -2148,6 +2149,14 @@ let AddedComplexity = 400, Predicates = [HasP9Vector] in {
                                  [(set v4f32:$XT,
                                      (int_ppc_vsx_xvcvsphp v4f32:$XB))]>;
 
+  } // UseVSXReg = 1
+
+  // Pattern for matching Vector HP -> Vector SP intrinsic. Defined as a
+  // seperate pattern so that it can convert the input register class from
+  // VRRC(v8i16) to VSRC.
+  def : Pat<(v4f32 (int_ppc_vsx_xvcvhpsp v8i16:$A)),
+            (v4f32 (XVCVHPSP (COPY_TO_REGCLASS $A, VSRC)))>;
+
   class Z23_VT5_R1_VB5_RMC2_EX1<bits<6> opcode, bits<8> xo, bit ex, string opc,
                                 list<dag> pattern>
     : Z23Form_1<opcode, xo,

llvm/test/CodeGen/PowerPC/vsx-p9.ll

@@ -331,4 +331,15 @@ entry:
 ; Function Attrs: nounwind readnone
 declare <2 x i64> @llvm.ppc.vsx.xvtstdcdp(<2 x double> %a, i32 %b)
 
+define <4 x float> @testXVCVHPSP(<8 x i16> %a) {
+entry:
+  %0 = tail call <4 x float>@llvm.ppc.vsx.xvcvhpsp(<8 x i16> %a)
+  ret <4 x float> %0
+; CHECK-LABEL: testXVCVHPSP
+; CHECK: xvcvhpsp 34, 34
+; CHECK: blr
+}
+; Function Attrs: nounwind readnone
+declare <4 x float>@llvm.ppc.vsx.xvcvhpsp(<8 x i16>)
+
 declare void @sink(...)