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[AArch64] Use i32 extract from UADDV in popcount lowering. #140718

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Merged
merged 2 commits into from
May 20, 2025
Merged

[AArch64] Use i32 extract from UADDV in popcount lowering. #140718

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e233002
[AArch64] Add a test for extract from ctpop, #140707. NFC
davemgreen May 20, 2025
8789d19
[AArch64] Use i32 extract from UADDV in popcount lowering.
davemgreen May 20, 2025
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11 changes: 4 additions & 7 deletions llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -10852,13 +10852,10 @@ SDValue AArch64TargetLowering::LowerCTPOP_PARITY(SDValue Op,

SDValue CtPop = DAG.getNode(ISD::CTPOP, DL, MVT::v8i8, Val);
SDValue AddV = DAG.getNode(AArch64ISD::UADDV, DL, MVT::v8i8, CtPop);
if (VT == MVT::i32)
AddV = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, MVT::i32, AddV,
DAG.getConstant(0, DL, MVT::i64));
else
AddV = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, VT,
DAG.getNode(AArch64ISD::NVCAST, DL, MVT::v1i64, AddV),
DAG.getConstant(0, DL, MVT::i64));
AddV = DAG.getNode(AArch64ISD::NVCAST, DL,
VT == MVT::i32 ? MVT::v2i32 : MVT::v1i64, AddV);
AddV = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, VT, AddV,
DAG.getConstant(0, DL, MVT::i64));
if (IsParity)
AddV = DAG.getNode(ISD::AND, DL, VT, AddV, DAG.getConstant(1, DL, VT));
return AddV;
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109 changes: 109 additions & 0 deletions llvm/test/CodeGen/AArch64/popcount.ll
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Expand Up @@ -648,4 +648,113 @@ Entry:
ret <4 x i16> %1
}

define i32 @ctpop_into_extract(ptr %p) {
; CHECKO0-LABEL: ctpop_into_extract:
; CHECKO0: // %bb.0:
; CHECKO0-NEXT: mov w8, #-1 // =0xffffffff
; CHECKO0-NEXT: // implicit-def: $d1
; CHECKO0-NEXT: // implicit-def: $q0
; CHECKO0-NEXT: fmov d0, d1
; CHECKO0-NEXT: mov v0.s[0], w8
; CHECKO0-NEXT: fmov d2, d0
; CHECKO0-NEXT: ldr d0, [x0]
; CHECKO0-NEXT: fmov s1, s0
; CHECKO0-NEXT: fmov w8, s1
; CHECKO0-NEXT: fmov s1, w8
; CHECKO0-NEXT: // kill: def $d1 killed $s1
; CHECKO0-NEXT: cnt v1.8b, v1.8b
; CHECKO0-NEXT: uaddlv h1, v1.8b
; CHECKO0-NEXT: // kill: def $q1 killed $h1
; CHECKO0-NEXT: // kill: def $s1 killed $s1 killed $q1
; CHECKO0-NEXT: fmov w8, s1
; CHECKO0-NEXT: // implicit-def: $q1
; CHECKO0-NEXT: fmov d1, d2
; CHECKO0-NEXT: mov v1.s[1], w8
; CHECKO0-NEXT: // kill: def $d1 killed $d1 killed $q1
; CHECKO0-NEXT: sub v0.2s, v0.2s, v1.2s
; CHECKO0-NEXT: str d0, [x0]
; CHECKO0-NEXT: mov w0, wzr
; CHECKO0-NEXT: ret
;
; CHECK-LABEL: ctpop_into_extract:
; CHECK: // %bb.0:
; CHECK-NEXT: ldr d0, [x0]
; CHECK-NEXT: movi v2.2d, #0xffffffffffffffff
; CHECK-NEXT: mov x8, x0
; CHECK-NEXT: mov w0, wzr
; CHECK-NEXT: fmov w9, s0
; CHECK-NEXT: fmov s1, w9
; CHECK-NEXT: cnt v1.8b, v1.8b
; CHECK-NEXT: addv b1, v1.8b
; CHECK-NEXT: mov v2.s[1], v1.s[0]
; CHECK-NEXT: sub v0.2s, v0.2s, v2.2s
; CHECK-NEXT: str d0, [x8]
; CHECK-NEXT: ret
;
; BE-LABEL: ctpop_into_extract:
; BE: // %bb.0:
; BE-NEXT: ld1 { v0.2s }, [x0]
; BE-NEXT: movi v2.2d, #0xffffffffffffffff
; BE-NEXT: mov x8, x0
; BE-NEXT: mov w0, wzr
; BE-NEXT: fmov w9, s0
; BE-NEXT: fmov s1, w9
; BE-NEXT: cnt v1.8b, v1.8b
; BE-NEXT: addv b1, v1.8b
; BE-NEXT: mov v2.s[1], v1.s[0]
; BE-NEXT: sub v0.2s, v0.2s, v2.2s
; BE-NEXT: st1 { v0.2s }, [x8]
; BE-NEXT: ret
;
; GISEL-LABEL: ctpop_into_extract:
; GISEL: // %bb.0:
; GISEL-NEXT: ldr d0, [x0]
; GISEL-NEXT: mov w9, #-1 // =0xffffffff
; GISEL-NEXT: mov x8, x0
; GISEL-NEXT: mov v2.s[0], w9
; GISEL-NEXT: mov w0, wzr
; GISEL-NEXT: fmov w10, s0
; GISEL-NEXT: fmov s1, w10
; GISEL-NEXT: cnt v1.8b, v1.8b
; GISEL-NEXT: uaddlv h1, v1.8b
; GISEL-NEXT: mov v2.s[1], v1.s[0]
; GISEL-NEXT: sub v0.2s, v0.2s, v2.2s
; GISEL-NEXT: str d0, [x8]
; GISEL-NEXT: ret
;
; GISELO0-LABEL: ctpop_into_extract:
; GISELO0: // %bb.0:
; GISELO0-NEXT: mov w8, #-1 // =0xffffffff
; GISELO0-NEXT: // implicit-def: $d1
; GISELO0-NEXT: // implicit-def: $q0
; GISELO0-NEXT: fmov d0, d1
; GISELO0-NEXT: mov v0.s[0], w8
; GISELO0-NEXT: fmov d2, d0
; GISELO0-NEXT: ldr d0, [x0]
; GISELO0-NEXT: fmov s1, s0
; GISELO0-NEXT: fmov w8, s1
; GISELO0-NEXT: fmov s1, w8
; GISELO0-NEXT: // kill: def $d1 killed $s1
; GISELO0-NEXT: cnt v1.8b, v1.8b
; GISELO0-NEXT: uaddlv h1, v1.8b
; GISELO0-NEXT: // kill: def $q1 killed $h1
; GISELO0-NEXT: // kill: def $s1 killed $s1 killed $q1
; GISELO0-NEXT: fmov w8, s1
; GISELO0-NEXT: // implicit-def: $q1
; GISELO0-NEXT: fmov d1, d2
; GISELO0-NEXT: mov v1.s[1], w8
; GISELO0-NEXT: // kill: def $d1 killed $d1 killed $q1
; GISELO0-NEXT: sub v0.2s, v0.2s, v1.2s
; GISELO0-NEXT: str d0, [x0]
; GISELO0-NEXT: mov w0, wzr
; GISELO0-NEXT: ret
%1 = load <2 x i32>, ptr %p, align 4
%2 = extractelement <2 x i32> %1, i64 0
%3 = call i32 @llvm.ctpop.i32(i32 %2)
%4 = insertelement <2 x i32> <i32 -1, i32 poison>, i32 %3, i64 1
%5 = sub <2 x i32> %1, %4
store <2 x i32> %5, ptr %p, align 4
ret i32 0
}

declare <4 x i16> @llvm.ctpop.v4i16(<4 x i16>)