Index: llvm/lib/Target/AArch64/AArch64SVEInstrInfo.td
===================================================================
--- llvm/lib/Target/AArch64/AArch64SVEInstrInfo.td
+++ llvm/lib/Target/AArch64/AArch64SVEInstrInfo.td
@@ -3581,4 +3581,9 @@
 def BFMLSLT_ZZZ_S : sve_bfloat_matmul_longvecl<0b1, 0b1, "bfmlslt">;
 def BFMLSLB_ZZZI_S : sve_bfloat_matmul_longvecl_idx<0b0, 0b1, "bfmlslb">;
 def BFMLSLT_ZZZI_S : sve_bfloat_matmul_longvecl_idx<0b1, 0b1, "bfmlslt">;
+
+def SDOT_2WAY_ZZZ_S  : sve2p1_two_way_dot_vv<"sdot", 0b0>;
+def UDOT_2WAY_ZZZ_S  : sve2p1_two_way_dot_vv<"udot", 0b1>;
+def SDOT_2WAY_ZZZI_S : sve2p1_two_way_dot_vvi<"sdot", 0b0>;
+def UDOT_2WAY_ZZZI_S : sve2p1_two_way_dot_vvi<"udot", 0b1>;
 } // End HasSVE2p1_or_HasSME2
Index: llvm/lib/Target/AArch64/SVEInstrFormats.td
===================================================================
--- llvm/lib/Target/AArch64/SVEInstrFormats.td
+++ llvm/lib/Target/AArch64/SVEInstrFormats.td
@@ -8654,3 +8654,44 @@
   def _S : sve2p1_fclamp<asm, 0b10, ZPR32>;
   def _D : sve2p1_fclamp<asm, 0b11, ZPR64>;
 }
+
+// SVE two-way dot product
+class sve2p1_two_way_dot_vv<string mnemonic, bit u>
+    : I<(outs ZPR32:$Zda), (ins ZPR32:$_Zda, ZPR16:$Zn, ZPR16:$Zm),
+        mnemonic, "\t$Zda, $Zn, $Zm",
+        "", []>, Sched<[]> {
+  bits<5> Zda;
+  bits<5> Zn;
+  bits<5> Zm;
+  let Inst{31-21} = 0b01000100000;
+  let Inst{20-16} = Zm;
+  let Inst{15-11} = 0b11001;
+  let Inst{10}    = u;
+  let Inst{9-5}   = Zn;
+  let Inst{4-0}   = Zda;
+
+  let Constraints = "$Zda = $_Zda";
+  let DestructiveInstType = DestructiveOther;
+}
+
+
+// SVE two-way dot product (indexed)
+class sve2p1_two_way_dot_vvi<string mnemonic, bit u>
+    : I<(outs ZPR32:$Zda), (ins ZPR32:$_Zda, ZPR16:$Zn, ZPR3b16:$Zm, VectorIndexS:$i2),
+        mnemonic, "\t$Zda, $Zn, $Zm$i2",
+        "", []>, Sched<[]> {
+  bits<5> Zda;
+  bits<5> Zn;
+  bits<3> Zm;
+  bits<2> i2;
+  let Inst{31-21} = 0b01000100100;
+  let Inst{20-19} = i2;
+  let Inst{18-16} = Zm;
+  let Inst{15-11} = 0b11001;
+  let Inst{10}    = u;
+  let Inst{9-5}   = Zn;
+  let Inst{4-0}   = Zda;
+
+  let Constraints = "$Zda = $_Zda";
+  let DestructiveInstType = DestructiveOther;
+}
Index: llvm/test/MC/AArch64/SVE2p1/sdot-diagnostics.s
===================================================================
--- /dev/null
+++ llvm/test/MC/AArch64/SVE2p1/sdot-diagnostics.s
@@ -0,0 +1,27 @@
+// RUN: not llvm-mc -triple=aarch64 -show-encoding -mattr=+sve2p1 2>&1 < %s | FileCheck %s
+
+// --------------------------------------------------------------------------//
+// Invalid vector lane index
+
+sdot z0.s, z0.h, z0.h[8]
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: vector lane must be an integer in range [0, 3].
+// CHECK-NEXT: sdot z0.s, z0.h, z0.h[8]
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+sdot z0.s, z0.h, z0.h[-1]
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: vector lane must be an integer in range [0, 3].
+// CHECK-NEXT: sdot z0.s, z0.h, z0.h[-1]
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+// --------------------------------------------------------------------------//
+// Invalid vector suffix
+
+sdot z0.h, z0.s, z0.s
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: sdot z0.h, z0.s, z0.s
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+sdot z0.b, z0.h, z0.h[1]
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: sdot z0.b, z0.h, z0.h[1]
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
Index: llvm/test/MC/AArch64/SVE2p1/sdot.s
===================================================================
--- /dev/null
+++ llvm/test/MC/AArch64/SVE2p1/sdot.s
@@ -0,0 +1,78 @@
+// RUN: llvm-mc -triple=aarch64 -show-encoding -mattr=+sme2 < %s \
+// RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+// RUN: llvm-mc -triple=aarch64 -show-encoding -mattr=+sve2p1 < %s \
+// RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+// RUN: not llvm-mc -triple=aarch64 -show-encoding < %s 2>&1 \
+// RUN:        | FileCheck %s --check-prefix=CHECK-ERROR
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -mattr=+sme2 < %s \
+// RUN:        | llvm-objdump -d --mattr=+sme2 - | FileCheck %s --check-prefix=CHECK-INST
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -mattr=+sme2 < %s \
+// RUN:        | llvm-objdump -d - | FileCheck %s --check-prefix=CHECK-UNKNOWN
+// RUN: llvm-mc -triple=aarch64 -show-encoding -mattr=+sme2 < %s \
+// RUN:        | sed '/.text/d' | sed 's/.*encoding: //g' \
+// RUN:        | llvm-mc -triple=aarch64 -mattr=+sme2 -disassemble -show-encoding \
+// RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+
+movprfx z23, z31
+sdot    z23.s, z13.h, z0.h[1]  // 01000100-10001000-11001001-10110111
+// CHECK-INST:  movprfx z23, z31
+// CHECK-INST: sdot    z23.s, z13.h, z0.h[1]
+// CHECK-ENCODING: [0xb7,0xc9,0x88,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4488c9b7 <unknown>
+
+sdot    z0.s, z0.h, z0.h[0]  // 01000100-10000000-11001000-00000000
+// CHECK-INST: sdot    z0.s, z0.h, z0.h[0]
+// CHECK-ENCODING: [0x00,0xc8,0x80,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4480c800 <unknown>
+
+sdot    z21.s, z10.h, z5.h[2]  // 01000100-10010101-11001001-01010101
+// CHECK-INST: sdot    z21.s, z10.h, z5.h[2]
+// CHECK-ENCODING: [0x55,0xc9,0x95,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4495c955 <unknown>
+
+sdot    z23.s, z13.h, z0.h[1]  // 01000100-10001000-11001001-10110111
+// CHECK-INST: sdot    z23.s, z13.h, z0.h[1]
+// CHECK-ENCODING: [0xb7,0xc9,0x88,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4488c9b7 <unknown>
+
+sdot    z31.s, z31.h, z7.h[3]  // 01000100-10011111-11001011-11111111
+// CHECK-INST: sdot    z31.s, z31.h, z7.h[3]
+// CHECK-ENCODING: [0xff,0xcb,0x9f,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 449fcbff <unknown>
+
+movprfx z23, z31
+sdot    z23.s, z13.h, z8.h  // 01000100-00001000-11001001-10110111
+// CHECK-INST:  movprfx z23, z31
+// CHECK-INST: sdot    z23.s, z13.h, z8.h
+// CHECK-ENCODING: [0xb7,0xc9,0x08,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4408c9b7 <unknown>
+
+sdot    z0.s, z0.h, z0.h  // 01000100-00000000-11001000-00000000
+// CHECK-INST: sdot    z0.s, z0.h, z0.h
+// CHECK-ENCODING: [0x00,0xc8,0x00,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4400c800 <unknown>
+
+sdot    z21.s, z10.h, z21.h  // 01000100-00010101-11001001-01010101
+// CHECK-INST: sdot    z21.s, z10.h, z21.h
+// CHECK-ENCODING: [0x55,0xc9,0x15,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4415c955 <unknown>
+
+sdot    z23.s, z13.h, z8.h  // 01000100-00001000-11001001-10110111
+// CHECK-INST: sdot    z23.s, z13.h, z8.h
+// CHECK-ENCODING: [0xb7,0xc9,0x08,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4408c9b7 <unknown>
+
+sdot    z31.s, z31.h, z31.h  // 01000100-00011111-11001011-11111111
+// CHECK-INST: sdot    z31.s, z31.h, z31.h
+// CHECK-ENCODING: [0xff,0xcb,0x1f,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 441fcbff <unknown>
Index: llvm/test/MC/AArch64/SVE2p1/udot-diagnostics.s
===================================================================
--- /dev/null
+++ llvm/test/MC/AArch64/SVE2p1/udot-diagnostics.s
@@ -0,0 +1,27 @@
+// RUN: not llvm-mc -triple=aarch64 -show-encoding -mattr=+sve2p1 2>&1 < %s | FileCheck %s
+
+// --------------------------------------------------------------------------//
+// Invalid vector lane index
+
+udot z0.s, z0.h, z0.h[8]
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: vector lane must be an integer in range [0, 3].
+// CHECK-NEXT: udot z0.s, z0.h, z0.h[8]
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+udot z0.s, z0.h, z0.h[-1]
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: vector lane must be an integer in range [0, 3].
+// CHECK-NEXT: udot z0.s, z0.h, z0.h[-1]
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+// --------------------------------------------------------------------------//
+// Invalid vector suffix
+
+udot z0.h, z0.s, z0.s
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: udot z0.h, z0.s, z0.s
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+udot z0.h, z0.s, z0.s[1]
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: udot z0.h, z0.s, z0.s[1]
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
Index: llvm/test/MC/AArch64/SVE2p1/udot.s
===================================================================
--- /dev/null
+++ llvm/test/MC/AArch64/SVE2p1/udot.s
@@ -0,0 +1,78 @@
+// RUN: llvm-mc -triple=aarch64 -show-encoding -mattr=+sme2 < %s \
+// RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+// RUN: llvm-mc -triple=aarch64 -show-encoding -mattr=+sve2p1 < %s \
+// RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+// RUN: not llvm-mc -triple=aarch64 -show-encoding < %s 2>&1 \
+// RUN:        | FileCheck %s --check-prefix=CHECK-ERROR
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -mattr=+sme2 < %s \
+// RUN:        | llvm-objdump -d --mattr=+sme2 - | FileCheck %s --check-prefix=CHECK-INST
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -mattr=+sme2 < %s \
+// RUN:        | llvm-objdump -d - | FileCheck %s --check-prefix=CHECK-UNKNOWN
+// RUN: llvm-mc -triple=aarch64 -show-encoding -mattr=+sme2 < %s \
+// RUN:        | sed '/.text/d' | sed 's/.*encoding: //g' \
+// RUN:        | llvm-mc -triple=aarch64 -mattr=+sme2 -disassemble -show-encoding \
+// RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+
+movprfx z23, z31
+udot    z23.s, z13.h, z0.h[1]  // 01000100-10001000-11001101-10110111
+// CHECK-INST:  movprfx z23, z31
+// CHECK-INST: udot    z23.s, z13.h, z0.h[1]
+// CHECK-ENCODING: [0xb7,0xcd,0x88,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4488cdb7 <unknown>
+
+udot    z0.s, z0.h, z0.h[0]  // 01000100-10000000-11001100-00000000
+// CHECK-INST: udot    z0.s, z0.h, z0.h[0]
+// CHECK-ENCODING: [0x00,0xcc,0x80,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4480cc00 <unknown>
+
+udot    z21.s, z10.h, z5.h[2]  // 01000100-10010101-11001101-01010101
+// CHECK-INST: udot    z21.s, z10.h, z5.h[2]
+// CHECK-ENCODING: [0x55,0xcd,0x95,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4495cd55 <unknown>
+
+udot    z23.s, z13.h, z0.h[1]  // 01000100-10001000-11001101-10110111
+// CHECK-INST: udot    z23.s, z13.h, z0.h[1]
+// CHECK-ENCODING: [0xb7,0xcd,0x88,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4488cdb7 <unknown>
+
+udot    z31.s, z31.h, z7.h[3]  // 01000100-10011111-11001111-11111111
+// CHECK-INST: udot    z31.s, z31.h, z7.h[3]
+// CHECK-ENCODING: [0xff,0xcf,0x9f,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 449fcfff <unknown>
+
+movprfx z23, z31
+udot    z23.s, z13.h, z8.h  // 01000100-00001000-11001101-10110111
+// CHECK-INST:  movprfx z23, z31
+// CHECK-INST: udot    z23.s, z13.h, z8.h
+// CHECK-ENCODING: [0xb7,0xcd,0x08,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4408cdb7 <unknown>
+
+udot    z0.s, z0.h, z0.h  // 01000100-00000000-11001100-00000000
+// CHECK-INST: udot    z0.s, z0.h, z0.h
+// CHECK-ENCODING: [0x00,0xcc,0x00,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4400cc00 <unknown>
+
+udot    z21.s, z10.h, z21.h  // 01000100-00010101-11001101-01010101
+// CHECK-INST: udot    z21.s, z10.h, z21.h
+// CHECK-ENCODING: [0x55,0xcd,0x15,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4415cd55 <unknown>
+
+udot    z23.s, z13.h, z8.h  // 01000100-00001000-11001101-10110111
+// CHECK-INST: udot    z23.s, z13.h, z8.h
+// CHECK-ENCODING: [0xb7,0xcd,0x08,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 4408cdb7 <unknown>
+
+udot    z31.s, z31.h, z31.h  // 01000100-00011111-11001111-11111111
+// CHECK-INST: udot    z31.s, z31.h, z31.h
+// CHECK-ENCODING: [0xff,0xcf,0x1f,0x44]
+// CHECK-ERROR: instruction requires: sme2 or sve2p1
+// CHECK-UNKNOWN: 441fcfff <unknown>