diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfoB.td b/llvm/lib/Target/RISCV/RISCVInstrInfoB.td
--- a/llvm/lib/Target/RISCV/RISCVInstrInfoB.td
+++ b/llvm/lib/Target/RISCV/RISCVInstrInfoB.td
@@ -224,6 +224,12 @@
 def XNOR  : ALU_rr<0b0100000, 0b100, "xnor">, Sched<[]>;
 } // Predicates = [HasStdExtZbbOrZbp]
 
+let Predicates = [HasStdExtZba] in {
+def SH1ADD : ALU_rr<0b0010000, 0b010, "sh1add">, Sched<[]>;
+def SH2ADD : ALU_rr<0b0010000, 0b100, "sh2add">, Sched<[]>;
+def SH3ADD : ALU_rr<0b0010000, 0b110, "sh3add">, Sched<[]>;
+} // Predicates = [HasStdExtZba]
+
 let Predicates = [HasStdExtZbb] in {
 def SLO  : ALU_rr<0b0010000, 0b001, "slo">, Sched<[]>;
 def SRO  : ALU_rr<0b0010000, 0b101, "sro">, Sched<[]>;
@@ -372,6 +378,9 @@
 let Predicates = [HasStdExtZba, IsRV64] in {
 def SLLIUW : RVBShift_ri<0b00001, 0b001, OPC_OP_IMM_32, "slli.uw">, Sched<[]>;
 def ADDUW : ALUW_rr<0b0000100, 0b000, "add.uw">, Sched<[]>;
+def SH1ADDUW : ALUW_rr<0b0010000, 0b010, "sh1add.uw">, Sched<[]>;
+def SH2ADDUW : ALUW_rr<0b0010000, 0b100, "sh2add.uw">, Sched<[]>;
+def SH3ADDUW : ALUW_rr<0b0010000, 0b110, "sh3add.uw">, Sched<[]>;
 } // Predicates = [HasStdExtZbb, IsRV64]
 
 let Predicates = [HasStdExtZbb, IsRV64] in {
diff --git a/llvm/test/MC/RISCV/rv32zba-invalid.s b/llvm/test/MC/RISCV/rv32zba-invalid.s
new file mode 100644
--- /dev/null
+++ b/llvm/test/MC/RISCV/rv32zba-invalid.s
@@ -0,0 +1,8 @@
+# RUN: not llvm-mc -triple riscv32 -mattr=+experimental-b,experimental-zba < %s 2>&1 | FileCheck %s
+
+# Too few operands
+sh1add t0, t1 # CHECK: :[[@LINE]]:1: error: too few operands for instruction
+# Too few operands
+sh2add t0, t1 # CHECK: :[[@LINE]]:1: error: too few operands for instruction
+# Too few operands
+sh3add t0, t1 # CHECK: :[[@LINE]]:1: error: too few operands for instruction
diff --git a/llvm/test/MC/RISCV/rv32zba-valid.s b/llvm/test/MC/RISCV/rv32zba-valid.s
new file mode 100644
--- /dev/null
+++ b/llvm/test/MC/RISCV/rv32zba-valid.s
@@ -0,0 +1,23 @@
+# With B extension:
+# RUN: llvm-mc %s -triple=riscv32 -mattr=+experimental-b -show-encoding \
+# RUN:     | FileCheck -check-prefixes=CHECK-ASM,CHECK-ASM-AND-OBJ %s
+# RUN: llvm-mc -filetype=obj -triple=riscv32 -mattr=+experimental-b < %s \
+# RUN:     | llvm-objdump --mattr=+experimental-b -d -r - \
+# RUN:     | FileCheck --check-prefix=CHECK-ASM-AND-OBJ %s
+
+# With Bitmanip base extension:
+# RUN: llvm-mc %s -triple=riscv32 -mattr=+experimental-zba -show-encoding \
+# RUN:     | FileCheck -check-prefixes=CHECK-ASM,CHECK-ASM-AND-OBJ %s
+# RUN: llvm-mc -filetype=obj -triple=riscv32 -mattr=+experimental-zba < %s \
+# RUN:     | llvm-objdump --mattr=+experimental-zba -d -r - \
+# RUN:     | FileCheck --check-prefix=CHECK-ASM-AND-OBJ %s
+
+# CHECK-ASM-AND-OBJ: sh1add t0, t1, t2
+# CHECK-ASM: encoding: [0xb3,0x22,0x73,0x20]
+sh1add t0, t1, t2
+# CHECK-ASM-AND-OBJ: sh2add t0, t1, t2
+# CHECK-ASM: encoding: [0xb3,0x42,0x73,0x20]
+sh2add t0, t1, t2
+# CHECK-ASM-AND-OBJ: sh3add t0, t1, t2
+# CHECK-ASM: encoding: [0xb3,0x62,0x73,0x20]
+sh3add t0, t1, t2
diff --git a/llvm/test/MC/RISCV/rv64zba-invalid.s b/llvm/test/MC/RISCV/rv64zba-invalid.s
--- a/llvm/test/MC/RISCV/rv64zba-invalid.s
+++ b/llvm/test/MC/RISCV/rv64zba-invalid.s
@@ -7,3 +7,9 @@
 slli.uw t0, t1, -1 # CHECK: :[[@LINE]]:17: error: immediate must be an integer in the range [0, 63]
 # Too few operands
 add.uw t0, t1 # CHECK: :[[@LINE]]:1: error: too few operands for instruction
+# Too few operands
+sh1add.uw t0, t1 # CHECK: :[[@LINE]]:1: error: too few operands for instruction
+# Too few operands
+sh2add.uw t0, t1 # CHECK: :[[@LINE]]:1: error: too few operands for instruction
+# Too few operands
+sh3add.uw t0, t1 # CHECK: :[[@LINE]]:1: error: too few operands for instruction
diff --git a/llvm/test/MC/RISCV/rv64zba-valid.s b/llvm/test/MC/RISCV/rv64zba-valid.s
--- a/llvm/test/MC/RISCV/rv64zba-valid.s
+++ b/llvm/test/MC/RISCV/rv64zba-valid.s
@@ -18,3 +18,12 @@
 # CHECK-ASM-AND-OBJ: add.uw t0, t1, t2
 # CHECK-ASM: encoding: [0xbb,0x02,0x73,0x08]
 add.uw t0, t1, t2
+# CHECK-ASM-AND-OBJ: sh1add.uw t0, t1, t2
+# CHECK-ASM: encoding: [0xbb,0x22,0x73,0x20]
+sh1add.uw t0, t1, t2
+# CHECK-ASM-AND-OBJ: sh2add.uw t0, t1, t2
+# CHECK-ASM: encoding: [0xbb,0x42,0x73,0x20]
+sh2add.uw t0, t1, t2
+# CHECK-ASM-AND-OBJ: sh3add.uw t0, t1, t2
+# CHECK-ASM: encoding: [0xbb,0x62,0x73,0x20]
+sh3add.uw t0, t1, t2