[llvm] r227550 - [AArch64]Fix PR21675, a bug about lowering llvm.ctpop.i32. We should noot use "DAG.getUNDEF(MVT::v8i8)" to get all zero vector.

[Hao Liu]

Author: haoliu
Date: Thu Jan 29 20:13:53 2015
New Revision: 227550

URL: http://llvm.org/viewvc/llvm-project?rev=227550&view=rev
Log:
[AArch64]Fix PR21675, a bug about lowering llvm.ctpop.i32. We should noot use "DAG.getUNDEF(MVT::v8i8)" to get all zero vector.
Patch by Wei-cheng Wang.

Modified:
    llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp
    llvm/trunk/test/CodeGen/AArch64/arm64-popcnt.ll

Modified: llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp?rev=227550&r1=227549&r2=227550&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp Thu Jan 29 20:13:53 2015
@@ -3451,18 +3451,12 @@ SDValue AArch64TargetLowering::LowerCTPO
   SDValue Val = Op.getOperand(0);
   SDLoc DL(Op);
   EVT VT = Op.getValueType();
-  SDValue ZeroVec = DAG.getUNDEF(MVT::v8i8);
 
-  SDValue VecVal;
-  if (VT == MVT::i32) {
-    VecVal = DAG.getNode(ISD::BITCAST, DL, MVT::f32, Val);
-    VecVal = DAG.getTargetInsertSubreg(AArch64::ssub, DL, MVT::v8i8, ZeroVec,
-                                       VecVal);
-  } else {
-    VecVal = DAG.getNode(ISD::BITCAST, DL, MVT::v8i8, Val);
-  }
+  if (VT == MVT::i32)
+    Val = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i64, Val);
+  Val = DAG.getNode(ISD::BITCAST, DL, MVT::v8i8, Val);
 
-  SDValue CtPop = DAG.getNode(ISD::CTPOP, DL, MVT::v8i8, VecVal);
+  SDValue CtPop = DAG.getNode(ISD::CTPOP, DL, MVT::v8i8, Val);
   SDValue UaddLV = DAG.getNode(
       ISD::INTRINSIC_WO_CHAIN, DL, MVT::i32,
       DAG.getConstant(Intrinsic::aarch64_neon_uaddlv, MVT::i32), CtPop);

Modified: llvm/trunk/test/CodeGen/AArch64/arm64-popcnt.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AArch64/arm64-popcnt.ll?rev=227550&r1=227549&r2=227550&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AArch64/arm64-popcnt.ll (original)
+++ llvm/trunk/test/CodeGen/AArch64/arm64-popcnt.ll Thu Jan 29 20:13:53 2015
@@ -4,7 +4,8 @@
 define i32 @cnt32_advsimd(i32 %x) nounwind readnone {
   %cnt = tail call i32 @llvm.ctpop.i32(i32 %x)
   ret i32 %cnt
-; CHECK: fmov	s0, w0
+; CHECK: ubfx	x{{[0-9]+}}
+; CHECK: fmov	d0, x{{[0-9]+}}
 ; CHECK: cnt.8b	v0, v0
 ; CHECK: uaddlv.8b	h0, v0
 ; CHECK: fmov w0, s0
@@ -15,7 +16,24 @@ define i32 @cnt32_advsimd(i32 %x) nounwi
 ; CHECK-NONEON: and w{{[0-9]+}}, w{{[0-9]+}}, #0x33333333
 ; CHECK-NONEON: and w{{[0-9]+}}, w{{[0-9]+}}, #0xf0f0f0f
 ; CHECK-NONEON: mul
+}
 
+define i32 @cnt32_advsimd_2(<2 x i32> %x) {
+  %1 = extractelement <2 x i32> %x, i64 0
+  %2 = tail call i32 @llvm.ctpop.i32(i32 %1)
+  ret i32 %2
+; CHECK: fmov	w0, s0
+; CHECK: fmov	d0, x0
+; CHECK: cnt.8b	v0, v0
+; CHECK: uaddlv.8b	h0, v0
+; CHECK: fmov w0, s0
+; CHECK: ret
+; CHECK-NONEON-LABEL: cnt32_advsimd_2
+; CHECK-NONEON-NOT: 8b
+; CHECK-NONEON: and w{{[0-9]+}}, w{{[0-9]+}}, #0x55555555
+; CHECK-NONEON: and w{{[0-9]+}}, w{{[0-9]+}}, #0x33333333
+; CHECK-NONEON: and w{{[0-9]+}}, w{{[0-9]+}}, #0xf0f0f0f
+; CHECK-NONEON: mul
 }
 
 define i64 @cnt64_advsimd(i64 %x) nounwind readnone {