[AArch64][DAGCombine] Add performBuildVectorCombine 'extract_elt ~> anyext'

david-arm · david-arm · commit 487fa6f8c3af · 2022-07-29T09:51:09.000+01:00
A build vector of two extracted elements is equivalent to an extract subvector where the inner vector is any-extended to the extract_vector_elt VT, because extract_vector_elt has the effect of an any-extend. (build_vector (extract_elt_i16_to_i32 vec Idx+0) (extract_elt_i16_to_i32 vec Idx+1)) => (extract_subvector (anyext_i16_to_i32 vec) Idx) Depends on D130697 Differential Revision: https://reviews.llvm.org/D130698
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -888,7 +888,7 @@ AArch64TargetLowering::AArch64TargetLowering(const TargetMachine &TM,
   setTargetDAGCombine({ISD::ANY_EXTEND, ISD::ZERO_EXTEND, ISD::SIGN_EXTEND,
                        ISD::VECTOR_SPLICE, ISD::SIGN_EXTEND_INREG,
                        ISD::CONCAT_VECTORS, ISD::EXTRACT_SUBVECTOR,
-                       ISD::INSERT_SUBVECTOR, ISD::STORE});
+                       ISD::INSERT_SUBVECTOR, ISD::STORE, ISD::BUILD_VECTOR});
   if (Subtarget->supportsAddressTopByteIgnored())
     setTargetDAGCombine(ISD::LOAD);
 
@@ -16031,6 +16031,49 @@ static SDValue performVectorAddSubExtCombine(SDNode *N, SelectionDAG &DAG) {
   return SDValue();
 }
 
+static SDValue performBuildVectorCombine(SDNode *N,
+                                         TargetLowering::DAGCombinerInfo &DCI,
+                                         SelectionDAG &DAG) {
+  SDLoc DL(N);
+
+  // A build vector of two extracted elements is equivalent to an
+  // extract subvector where the inner vector is any-extended to the
+  // extract_vector_elt VT.
+  //    (build_vector (extract_elt_iXX_to_i32 vec Idx+0)
+  //                  (extract_elt_iXX_to_i32 vec Idx+1))
+  // => (extract_subvector (anyext_iXX_to_i32 vec) Idx)
+
+  // For now, only consider the v2i32 case, which arises as a result of
+  // legalization.
+  if (N->getValueType(0) != MVT::v2i32)
+    return SDValue();
+
+  SDValue Elt0 = N->getOperand(0), Elt1 = N->getOperand(1);
+  // Reminder, EXTRACT_VECTOR_ELT has the effect of any-extending to its VT.
+  if (Elt0->getOpcode() == ISD::EXTRACT_VECTOR_ELT &&
+      Elt1->getOpcode() == ISD::EXTRACT_VECTOR_ELT &&
+      // Constant index.
+      isa<ConstantSDNode>(Elt0->getOperand(1)) &&
+      isa<ConstantSDNode>(Elt1->getOperand(1)) &&
+      // Both EXTRACT_VECTOR_ELT from same vector...
+      Elt0->getOperand(0) == Elt1->getOperand(0) &&
+      // ... and contiguous. First element's index +1 == second element's index.
+      Elt0->getConstantOperandVal(1) + 1 == Elt1->getConstantOperandVal(1)) {
+    SDValue VecToExtend = Elt0->getOperand(0);
+    EVT ExtVT = VecToExtend.getValueType().changeVectorElementType(MVT::i32);
+    if (!DAG.getTargetLoweringInfo().isTypeLegal(ExtVT))
+      return SDValue();
+
+    SDValue SubvectorIdx = DAG.getVectorIdxConstant(Elt0->getConstantOperandVal(1), DL);
+
+    SDValue Ext = DAG.getNode(ISD::ANY_EXTEND, DL, ExtVT, VecToExtend);
+    return DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, MVT::v2i32, Ext,
+                       SubvectorIdx);
+  }
+
+  return SDValue();
+}
+
 static SDValue performAddSubCombine(SDNode *N,
                                     TargetLowering::DAGCombinerInfo &DCI,
                                     SelectionDAG &DAG) {
@@ -19500,6 +19543,8 @@ SDValue AArch64TargetLowering::PerformDAGCombine(SDNode *N,
   case ISD::ADD:
   case ISD::SUB:
     return performAddSubCombine(N, DCI, DAG);
+  case ISD::BUILD_VECTOR:
+    return performBuildVectorCombine(N, DCI, DAG);
   case AArch64ISD::ANDS:
     return performFlagSettingCombine(N, DCI, ISD::AND);
   case AArch64ISD::ADC:
diff --git a/llvm/test/CodeGen/AArch64/bitcast-promote-widen.ll b/llvm/test/CodeGen/AArch64/bitcast-promote-widen.ll
@@ -6,11 +6,7 @@
 define <2 x i16> @bitcast_v2i16_v2f16(<2 x half> %x) {
 ; CHECK-LABEL: bitcast_v2i16_v2f16:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    // kill: def $d0 killed $d0 def $q0
-; CHECK-NEXT:    umov w8, v0.h[0]
-; CHECK-NEXT:    umov w9, v0.h[1]
-; CHECK-NEXT:    fmov s0, w8
-; CHECK-NEXT:    mov v0.s[1], w9
+; CHECK-NEXT:    ushll v0.4s, v0.4h, #0
 ; CHECK-NEXT:    // kill: def $d0 killed $d0 killed $q0
 ; CHECK-NEXT:    ret
   %y = bitcast <2 x half> %x to <2 x i16>
diff --git a/llvm/test/CodeGen/AArch64/sve-fixed-length-extract-subvector.ll b/llvm/test/CodeGen/AArch64/sve-fixed-length-extract-subvector.ll
@@ -101,11 +101,8 @@ define void @extract_subvector_v256i8(<256 x i8>* %a, <128 x i8>* %b) vscale_ran
 define <2 x i16> @extract_subvector_v4i16(<4 x i16> %op) vscale_range(2,0) #0 {
 ; CHECK-LABEL: extract_subvector_v4i16:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    // kill: def $d0 killed $d0 def $q0
-; CHECK-NEXT:    umov w8, v0.h[2]
-; CHECK-NEXT:    umov w9, v0.h[3]
-; CHECK-NEXT:    fmov s0, w8
-; CHECK-NEXT:    mov v0.s[1], w9
+; CHECK-NEXT:    ushll v0.4s, v0.4h, #0
+; CHECK-NEXT:    ext v0.16b, v0.16b, v0.16b, #8
 ; CHECK-NEXT:    // kill: def $d0 killed $d0 killed $q0
 ; CHECK-NEXT:    ret
   %ret = call <2 x i16> @llvm.vector.extract.v2i16.v4i16(<4 x i16> %op, i64 2)
diff --git a/llvm/test/CodeGen/AArch64/sve-fixed-length-masked-gather.ll b/llvm/test/CodeGen/AArch64/sve-fixed-length-masked-gather.ll
@@ -575,10 +575,7 @@ define void @masked_gather_v2f16(<2 x half>* %a, <2 x half*>* %b) vscale_range(2
 ; CHECK-NEXT:    movi d0, #0000000000000000
 ; CHECK-NEXT:    ptrue p0.d, vl4
 ; CHECK-NEXT:    fcmeq v1.4h, v1.4h, #0.0
-; CHECK-NEXT:    umov w8, v1.h[0]
-; CHECK-NEXT:    umov w9, v1.h[1]
-; CHECK-NEXT:    fmov s1, w8
-; CHECK-NEXT:    mov v1.s[1], w9
+; CHECK-NEXT:    ushll v1.4s, v1.4h, #0
 ; CHECK-NEXT:    shl v1.2s, v1.2s, #16
 ; CHECK-NEXT:    sshr v1.2s, v1.2s, #16
 ; CHECK-NEXT:    fmov w8, s1
diff --git a/llvm/test/CodeGen/AArch64/sve-fixed-length-masked-loads.ll b/llvm/test/CodeGen/AArch64/sve-fixed-length-masked-loads.ll
@@ -17,10 +17,7 @@ define <2 x half> @masked_load_v2f16(<2 x half>* %ap, <2 x half>* %bp) vscale_ra
 ; CHECK-NEXT:    ldr s2, [x1]
 ; CHECK-NEXT:    ptrue p0.h, vl4
 ; CHECK-NEXT:    fcmeq v1.4h, v1.4h, v2.4h
-; CHECK-NEXT:    umov w8, v1.h[0]
-; CHECK-NEXT:    umov w9, v1.h[1]
-; CHECK-NEXT:    fmov s1, w8
-; CHECK-NEXT:    mov v1.s[1], w9
+; CHECK-NEXT:    ushll v1.4s, v1.4h, #0
 ; CHECK-NEXT:    shl v1.2s, v1.2s, #16
 ; CHECK-NEXT:    sshr v1.2s, v1.2s, #16
 ; CHECK-NEXT:    fmov w8, s1
diff --git a/llvm/test/CodeGen/AArch64/sve-fixed-length-masked-scatter.ll b/llvm/test/CodeGen/AArch64/sve-fixed-length-masked-scatter.ll
@@ -538,10 +538,7 @@ define void @masked_scatter_v2f16(<2 x half>* %a, <2 x half*>* %b) vscale_range(
 ; CHECK-NEXT:    ptrue p0.d, vl4
 ; CHECK-NEXT:    fcmeq v2.4h, v1.4h, #0.0
 ; CHECK-NEXT:    uunpklo z1.s, z1.h
-; CHECK-NEXT:    umov w8, v2.h[0]
-; CHECK-NEXT:    umov w9, v2.h[1]
-; CHECK-NEXT:    fmov s2, w8
-; CHECK-NEXT:    mov v2.s[1], w9
+; CHECK-NEXT:    ushll v2.4s, v2.4h, #0
 ; CHECK-NEXT:    shl v2.2s, v2.2s, #16
 ; CHECK-NEXT:    sshr v2.2s, v2.2s, #16
 ; CHECK-NEXT:    fmov w8, s2
diff --git a/llvm/test/CodeGen/AArch64/sve-fixed-length-masked-stores.ll b/llvm/test/CodeGen/AArch64/sve-fixed-length-masked-stores.ll
@@ -17,10 +17,7 @@ define void @masked_store_v2f16(<2 x half>* %ap, <2 x half>* %bp) vscale_range(2
 ; CHECK-NEXT:    ldr s2, [x1]
 ; CHECK-NEXT:    ptrue p0.h, vl4
 ; CHECK-NEXT:    fcmeq v2.4h, v1.4h, v2.4h
-; CHECK-NEXT:    umov w8, v2.h[0]
-; CHECK-NEXT:    umov w9, v2.h[1]
-; CHECK-NEXT:    fmov s2, w8
-; CHECK-NEXT:    mov v2.s[1], w9
+; CHECK-NEXT:    ushll v2.4s, v2.4h, #0
 ; CHECK-NEXT:    shl v2.2s, v2.2s, #16
 ; CHECK-NEXT:    sshr v2.2s, v2.2s, #16
 ; CHECK-NEXT:    fmov w8, s2
diff --git a/llvm/test/CodeGen/AArch64/vector-fcvt.ll b/llvm/test/CodeGen/AArch64/vector-fcvt.ll
@@ -194,23 +194,16 @@ define <8 x float> @uitofp_i64_float(<8 x i64> %a) {
 define <4 x double> @sitofp_v4i8_double(<4 x i8> %a) {
 ; CHECK-LABEL: sitofp_v4i8_double:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    // kill: def $d0 killed $d0 def $q0
-; CHECK-NEXT:    umov w8, v0.h[0]
-; CHECK-NEXT:    umov w9, v0.h[2]
-; CHECK-NEXT:    umov w10, v0.h[1]
-; CHECK-NEXT:    fmov s1, w8
-; CHECK-NEXT:    umov w8, v0.h[3]
-; CHECK-NEXT:    fmov s0, w9
-; CHECK-NEXT:    mov v1.s[1], w10
-; CHECK-NEXT:    mov v0.s[1], w8
-; CHECK-NEXT:    shl v1.2s, v1.2s, #24
+; CHECK-NEXT:    ushll v0.4s, v0.4h, #0
+; CHECK-NEXT:    ext v1.16b, v0.16b, v0.16b, #8
 ; CHECK-NEXT:    shl v0.2s, v0.2s, #24
-; CHECK-NEXT:    sshr v1.2s, v1.2s, #24
 ; CHECK-NEXT:    sshr v0.2s, v0.2s, #24
+; CHECK-NEXT:    shl v1.2s, v1.2s, #24
+; CHECK-NEXT:    sshll v0.2d, v0.2s, #0
+; CHECK-NEXT:    sshr v1.2s, v1.2s, #24
+; CHECK-NEXT:    scvtf v0.2d, v0.2d
 ; CHECK-NEXT:    sshll v1.2d, v1.2s, #0
-; CHECK-NEXT:    sshll v2.2d, v0.2s, #0
-; CHECK-NEXT:    scvtf v0.2d, v1.2d
-; CHECK-NEXT:    scvtf v1.2d, v2.2d
+; CHECK-NEXT:    scvtf v1.2d, v1.2d
 ; CHECK-NEXT:    ret
   %1 = sitofp <4 x i8> %a to <4 x double>
   ret <4 x double> %1
@@ -333,39 +326,26 @@ define <16 x double> @sitofp_v16i8_double(<16 x i8> %a) {
 define <8 x double> @sitofp_i16_double(<8 x i16> %a) {
 ; CHECK-LABEL: sitofp_i16_double:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    ext v1.16b, v0.16b, v0.16b, #8
-; CHECK-NEXT:    umov w8, v0.h[0]
-; CHECK-NEXT:    umov w9, v0.h[2]
-; CHECK-NEXT:    umov w11, v0.h[1]
-; CHECK-NEXT:    umov w10, v1.h[0]
-; CHECK-NEXT:    umov w12, v1.h[2]
-; CHECK-NEXT:    fmov s2, w8
-; CHECK-NEXT:    umov w8, v0.h[3]
-; CHECK-NEXT:    fmov s0, w9
-; CHECK-NEXT:    umov w9, v1.h[1]
-; CHECK-NEXT:    fmov s3, w10
-; CHECK-NEXT:    umov w10, v1.h[3]
-; CHECK-NEXT:    fmov s1, w12
-; CHECK-NEXT:    mov v0.s[1], w8
-; CHECK-NEXT:    mov v2.s[1], w11
-; CHECK-NEXT:    mov v3.s[1], w9
-; CHECK-NEXT:    mov v1.s[1], w10
-; CHECK-NEXT:    shl v0.2s, v0.2s, #16
-; CHECK-NEXT:    shl v2.2s, v2.2s, #16
-; CHECK-NEXT:    sshr v0.2s, v0.2s, #16
-; CHECK-NEXT:    shl v3.2s, v3.2s, #16
-; CHECK-NEXT:    shl v1.2s, v1.2s, #16
+; CHECK-NEXT:    ushll2 v1.4s, v0.8h, #0
+; CHECK-NEXT:    ushll v0.4s, v0.4h, #0
+; CHECK-NEXT:    shl v2.2s, v1.2s, #16
+; CHECK-NEXT:    shl v3.2s, v0.2s, #16
+; CHECK-NEXT:    ext v1.16b, v1.16b, v1.16b, #8
 ; CHECK-NEXT:    sshr v2.2s, v2.2s, #16
-; CHECK-NEXT:    sshll v4.2d, v0.2s, #0
-; CHECK-NEXT:    sshr v0.2s, v3.2s, #16
-; CHECK-NEXT:    sshr v1.2s, v1.2s, #16
+; CHECK-NEXT:    ext v0.16b, v0.16b, v0.16b, #8
+; CHECK-NEXT:    sshr v3.2s, v3.2s, #16
 ; CHECK-NEXT:    sshll v2.2d, v2.2s, #0
-; CHECK-NEXT:    sshll v3.2d, v0.2s, #0
-; CHECK-NEXT:    sshll v5.2d, v1.2s, #0
-; CHECK-NEXT:    scvtf v0.2d, v2.2d
-; CHECK-NEXT:    scvtf v1.2d, v4.2d
-; CHECK-NEXT:    scvtf v2.2d, v3.2d
-; CHECK-NEXT:    scvtf v3.2d, v5.2d
+; CHECK-NEXT:    shl v1.2s, v1.2s, #16
+; CHECK-NEXT:    shl v0.2s, v0.2s, #16
+; CHECK-NEXT:    scvtf v2.2d, v2.2d
+; CHECK-NEXT:    sshr v1.2s, v1.2s, #16
+; CHECK-NEXT:    sshr v0.2s, v0.2s, #16
+; CHECK-NEXT:    sshll v3.2d, v3.2s, #0
+; CHECK-NEXT:    sshll v4.2d, v1.2s, #0
+; CHECK-NEXT:    sshll v1.2d, v0.2s, #0
+; CHECK-NEXT:    scvtf v0.2d, v3.2d
+; CHECK-NEXT:    scvtf v1.2d, v1.2d
+; CHECK-NEXT:    scvtf v3.2d, v4.2d
 ; CHECK-NEXT:    ret
   %1 = sitofp <8 x i16> %a to <8 x double>
   ret <8 x double> %1
@@ -402,22 +382,15 @@ define <8 x double> @sitofp_i64_double(<8 x i64> %a) {
 define <4 x double> @uitofp_v4i8_double(<4 x i8> %a) {
 ; CHECK-LABEL: uitofp_v4i8_double:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    // kill: def $d0 killed $d0 def $q0
-; CHECK-NEXT:    umov w8, v0.h[0]
-; CHECK-NEXT:    umov w9, v0.h[2]
-; CHECK-NEXT:    umov w10, v0.h[1]
+; CHECK-NEXT:    ushll v0.4s, v0.4h, #0
 ; CHECK-NEXT:    movi d1, #0x0000ff000000ff
-; CHECK-NEXT:    fmov s2, w8
-; CHECK-NEXT:    umov w8, v0.h[3]
-; CHECK-NEXT:    fmov s0, w9
-; CHECK-NEXT:    mov v2.s[1], w10
-; CHECK-NEXT:    mov v0.s[1], w8
-; CHECK-NEXT:    and v2.8b, v2.8b, v1.8b
+; CHECK-NEXT:    ext v2.16b, v0.16b, v0.16b, #8
 ; CHECK-NEXT:    and v0.8b, v0.8b, v1.8b
-; CHECK-NEXT:    ushll v1.2d, v2.2s, #0
-; CHECK-NEXT:    ushll v2.2d, v0.2s, #0
-; CHECK-NEXT:    ucvtf v0.2d, v1.2d
-; CHECK-NEXT:    ucvtf v1.2d, v2.2d
+; CHECK-NEXT:    ushll v0.2d, v0.2s, #0
+; CHECK-NEXT:    and v1.8b, v2.8b, v1.8b
+; CHECK-NEXT:    ushll v1.2d, v1.2s, #0
+; CHECK-NEXT:    ucvtf v0.2d, v0.2d
+; CHECK-NEXT:    ucvtf v1.2d, v1.2d
 ; CHECK-NEXT:    ret
   %1 = uitofp <4 x i8> %a to <4 x double>
   ret <4 x double> %1
@@ -530,36 +503,23 @@ define <16 x double> @uitofp_v16i8_double(<16 x i8> %a) {
 define <8 x double> @uitofp_i16_double(<8 x i16> %a) {
 ; CHECK-LABEL: uitofp_i16_double:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    ext v2.16b, v0.16b, v0.16b, #8
-; CHECK-NEXT:    umov w8, v0.h[0]
-; CHECK-NEXT:    umov w9, v0.h[2]
-; CHECK-NEXT:    umov w11, v0.h[1]
 ; CHECK-NEXT:    movi d1, #0x00ffff0000ffff
-; CHECK-NEXT:    umov w10, v2.h[0]
-; CHECK-NEXT:    umov w12, v2.h[2]
-; CHECK-NEXT:    fmov s3, w8
-; CHECK-NEXT:    umov w8, v0.h[3]
-; CHECK-NEXT:    fmov s0, w9
-; CHECK-NEXT:    umov w9, v2.h[1]
-; CHECK-NEXT:    fmov s4, w10
-; CHECK-NEXT:    umov w10, v2.h[3]
-; CHECK-NEXT:    fmov s2, w12
-; CHECK-NEXT:    mov v0.s[1], w8
-; CHECK-NEXT:    mov v3.s[1], w11
-; CHECK-NEXT:    mov v4.s[1], w9
-; CHECK-NEXT:    mov v2.s[1], w10
-; CHECK-NEXT:    and v0.8b, v0.8b, v1.8b
-; CHECK-NEXT:    and v3.8b, v3.8b, v1.8b
-; CHECK-NEXT:    ushll v5.2d, v0.2s, #0
-; CHECK-NEXT:    and v0.8b, v4.8b, v1.8b
-; CHECK-NEXT:    and v1.8b, v2.8b, v1.8b
+; CHECK-NEXT:    ushll2 v2.4s, v0.8h, #0
+; CHECK-NEXT:    ushll v0.4s, v0.4h, #0
+; CHECK-NEXT:    and v3.8b, v2.8b, v1.8b
+; CHECK-NEXT:    and v4.8b, v0.8b, v1.8b
+; CHECK-NEXT:    ext v2.16b, v2.16b, v2.16b, #8
+; CHECK-NEXT:    ext v0.16b, v0.16b, v0.16b, #8
 ; CHECK-NEXT:    ushll v3.2d, v3.2s, #0
-; CHECK-NEXT:    ushll v2.2d, v0.2s, #0
-; CHECK-NEXT:    ushll v4.2d, v1.2s, #0
-; CHECK-NEXT:    ucvtf v0.2d, v3.2d
-; CHECK-NEXT:    ucvtf v1.2d, v5.2d
-; CHECK-NEXT:    ucvtf v2.2d, v2.2d
-; CHECK-NEXT:    ucvtf v3.2d, v4.2d
+; CHECK-NEXT:    ushll v4.2d, v4.2s, #0
+; CHECK-NEXT:    and v2.8b, v2.8b, v1.8b
+; CHECK-NEXT:    and v0.8b, v0.8b, v1.8b
+; CHECK-NEXT:    ushll v5.2d, v2.2s, #0
+; CHECK-NEXT:    ucvtf v2.2d, v3.2d
+; CHECK-NEXT:    ushll v1.2d, v0.2s, #0
+; CHECK-NEXT:    ucvtf v0.2d, v4.2d
+; CHECK-NEXT:    ucvtf v1.2d, v1.2d
+; CHECK-NEXT:    ucvtf v3.2d, v5.2d
 ; CHECK-NEXT:    ret
   %1 = uitofp <8 x i16> %a to <8 x double>
   ret <8 x double> %1
