Index: llvm/lib/Target/RISCV/RISCVInstrInfoB.td
===================================================================
--- llvm/lib/Target/RISCV/RISCVInstrInfoB.td
+++ llvm/lib/Target/RISCV/RISCVInstrInfoB.td
@@ -653,10 +653,6 @@
           (SLO GPR:$rs1, GPR:$rs2)>;
 def : Pat<(xor (srl (xor GPR:$rs1, -1), GPR:$rs2), -1),
           (SRO GPR:$rs1, GPR:$rs2)>;
-def : Pat<(SLOIPat GPR:$rs1, uimmlog2xlen:$shamt),
-          (SLOI GPR:$rs1, uimmlog2xlen:$shamt)>;
-def : Pat<(SROIPat GPR:$rs1, uimmlog2xlen:$shamt),
-          (SROI GPR:$rs1, uimmlog2xlen:$shamt)>;
 } // Predicates = [HasStdExtZbb]
 
 let Predicates = [HasStdExtZbbOrZbp] in {
@@ -666,6 +662,51 @@
 def : Pat<(fshr GPR:$rs1, GPR:$rs1, GPR:$rs2), (ROR GPR:$rs1, GPR:$rs2)>;
 } // Predicates = [HasStdExtZbbOrZbp]
 
+let Predicates = [HasStdExtZbs, IsRV32] in
+def : Pat<(and (xor (shl 1, (and GPR:$rs2, 31)), -1), GPR:$rs1),
+          (SBCLR GPR:$rs1, GPR:$rs2)>;
+let Predicates = [HasStdExtZbs, IsRV64] in
+def : Pat<(and (xor (shl 1, (and GPR:$rs2, 63)), -1), GPR:$rs1),
+          (SBCLR GPR:$rs1, GPR:$rs2)>;
+
+let Predicates = [HasStdExtZbs] in
+def : Pat<(and (rotl -2, GPR:$rs2), GPR:$rs1), (SBCLR GPR:$rs1, GPR:$rs2)>;
+
+let Predicates = [HasStdExtZbs, IsRV32] in
+def : Pat<(or (shl 1, (and GPR:$rs2, 31)), GPR:$rs1),
+          (SBSET GPR:$rs1, GPR:$rs2)>;
+let Predicates = [HasStdExtZbs, IsRV64] in
+def : Pat<(or (shl 1, (and GPR:$rs2, 63)), GPR:$rs1),
+          (SBSET GPR:$rs1, GPR:$rs2)>;
+
+let Predicates = [HasStdExtZbs, IsRV32] in
+def : Pat<(xor (shl 1, (and GPR:$rs2, 31)), GPR:$rs1),
+          (SBINV GPR:$rs1, GPR:$rs2)>;
+let Predicates = [HasStdExtZbs, IsRV64] in
+def : Pat<(xor (shl 1, (and GPR:$rs2, 63)), GPR:$rs1),
+          (SBINV GPR:$rs1, GPR:$rs2)>;
+
+let Predicates = [HasStdExtZbs, IsRV32] in
+def : Pat<(and (srl GPR:$rs1, (and GPR:$rs2, 31)), 1),
+          (SBEXT GPR:$rs1, GPR:$rs2)>;
+
+let Predicates = [HasStdExtZbs, IsRV64] in
+def : Pat<(and (srl GPR:$rs1, (and GPR:$rs2, 63)), 1),
+          (SBEXT GPR:$rs1, GPR:$rs2)>;
+
+let Predicates = [HasStdExtZbb] in {
+def : Pat<(SLOIPat GPR:$rs1, uimmlog2xlen:$shamt),
+          (SLOI GPR:$rs1, uimmlog2xlen:$shamt)>;
+def : Pat<(SROIPat GPR:$rs1, uimmlog2xlen:$shamt),
+          (SROI GPR:$rs1, uimmlog2xlen:$shamt)>;
+} // Predicates = [HasStdExtZbb]
+
+// We don't pattern-match sbclri, sbseti, sbinvi because they get easily
+// selected already as andi, ori, and xori.
+let Predicates = [HasStdExtZbs] in
+def : Pat<(and (srl GPR:$rs1, uimmlog2xlen:$shamt), (XLenVT 1)),
+          (SBEXTI GPR:$rs1, uimmlog2xlen:$shamt)>;
+
 let Predicates = [HasStdExtZbp, IsRV32] in {
 def : Pat<(or (or (and (srl GPR:$rs1, (i32 1)), (i32 0x55555555)), GPR:$rs1),
               (and (shl GPR:$rs1, (i32 1)), (i32 0xAAAAAAAA))),
@@ -878,6 +919,21 @@
           (RORW GPR:$rs1, GPR:$rs2)>;
 } // Predicates = [HasStdExtZbbOrZbp, IsRV64]
 
+let Predicates = [HasStdExtZbs, IsRV64] in {
+def : Pat<(and (xor (riscv_sllw 1, (assertsexti32 GPR:$rs2)), -1),
+               (assertsexti32 GPR:$rs1)),
+          (SBCLRW GPR:$rs1, GPR:$rs2)>;
+def : Pat<(or (riscv_sllw 1, (assertsexti32 GPR:$rs2)),
+              (assertsexti32 GPR:$rs1)),
+          (SBSETW GPR:$rs1, GPR:$rs2)>;
+def : Pat<(xor (riscv_sllw 1, (assertsexti32 GPR:$rs2)),
+               (assertsexti32 GPR:$rs1)),
+          (SBINVW GPR:$rs1, GPR:$rs2)>;
+def : Pat<(and (riscv_srlw (assertsexti32 GPR:$rs1), (assertsexti32 GPR:$rs2)),
+               1),
+          (SBEXTW GPR:$rs1, GPR:$rs2)>;
+} // Predicates = [HasStdExtZbs, IsRV64]
+
 let Predicates = [HasStdExtZbp, IsRV64] in {
 def : Pat<(sext_inreg (or (or (and (srl GPR:$rs1, (i64 1)), (i64 0x55555555)),
                               GPR:$rs1),
Index: llvm/test/CodeGen/RISCV/rv32Zbs.ll
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/RISCV/rv32Zbs.ll
@@ -0,0 +1,217 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=riscv32 -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=RV32I
+; RUN: llc -mtriple=riscv32 -mattr=+experimental-b -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=RV32IB
+; RUN: llc -mtriple=riscv32 -mattr=+experimental-zbs -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=RV32IB
+
+define i32 @sbclr_i32(i32 %a, i32 %b) nounwind {
+; RV32I-LABEL: sbclr_i32:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    addi a2, zero, 1
+; RV32I-NEXT:    sll a1, a2, a1
+; RV32I-NEXT:    not a1, a1
+; RV32I-NEXT:    and a0, a1, a0
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbclr_i32:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    sbclr a0, a0, a1
+; RV32IB-NEXT:    ret
+  %and = and i32 %b, 31
+  %shl = shl nuw i32 1, %and
+  %neg = xor i32 %shl, -1
+  %and1 = and i32 %neg, %a
+  ret i32 %and1
+}
+
+; This pattern-matching of sbclr_i64 would generate an asm conflict if tested
+; on RV32. Until b the extension is ratified or new patterns can be matched to
+; this corner case we'll skip it.
+
+
+define i32 @sbset_i32(i32 %a, i32 %b) nounwind {
+; RV32I-LABEL: sbset_i32:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    addi a2, zero, 1
+; RV32I-NEXT:    sll a1, a2, a1
+; RV32I-NEXT:    or a0, a1, a0
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbset_i32:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    sbset a0, a0, a1
+; RV32IB-NEXT:    ret
+  %and = and i32 %b, 31
+  %shl = shl nuw i32 1, %and
+  %or = or i32 %shl, %a
+  ret i32 %or
+}
+
+define i64 @sbset_i64(i64 %a, i64 %b) nounwind {
+; RV32I-LABEL: sbset_i64:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    addi a3, zero, 1
+; RV32I-NEXT:    sll a2, a3, a2
+; RV32I-NEXT:    srai a3, a2, 31
+; RV32I-NEXT:    or a0, a2, a0
+; RV32I-NEXT:    or a1, a3, a1
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbset_i64:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    addi a3, zero, 1
+; RV32IB-NEXT:    sll a2, a3, a2
+; RV32IB-NEXT:    srai a3, a2, 31
+; RV32IB-NEXT:    or a0, a2, a0
+; RV32IB-NEXT:    or a1, a3, a1
+; RV32IB-NEXT:    ret
+  %1 = trunc i64 %b to i32
+  %conv = and i32 %1, 63
+  %shl = shl nuw i32 1, %conv
+  %conv1 = sext i32 %shl to i64
+  %or = or i64 %conv1, %a
+  ret i64 %or
+}
+
+define i32 @sbinv_i32(i32 %a, i32 %b) nounwind {
+; RV32I-LABEL: sbinv_i32:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    addi a2, zero, 1
+; RV32I-NEXT:    sll a1, a2, a1
+; RV32I-NEXT:    xor a0, a1, a0
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbinv_i32:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    sbinv a0, a0, a1
+; RV32IB-NEXT:    ret
+  %and = and i32 %b, 31
+  %shl = shl nuw i32 1, %and
+  %xor = xor i32 %shl, %a
+  ret i32 %xor
+}
+
+define i64 @sbinv_i64(i64 %a, i64 %b) nounwind {
+; RV32I-LABEL: sbinv_i64:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    addi a3, zero, 1
+; RV32I-NEXT:    sll a2, a3, a2
+; RV32I-NEXT:    srai a3, a2, 31
+; RV32I-NEXT:    xor a0, a2, a0
+; RV32I-NEXT:    xor a1, a3, a1
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbinv_i64:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    addi a3, zero, 1
+; RV32IB-NEXT:    sll a2, a3, a2
+; RV32IB-NEXT:    srai a3, a2, 31
+; RV32IB-NEXT:    xor a0, a2, a0
+; RV32IB-NEXT:    xor a1, a3, a1
+; RV32IB-NEXT:    ret
+  %1 = trunc i64 %b to i32
+  %conv = and i32 %1, 63
+  %shl = shl nuw i32 1, %conv
+  %conv1 = sext i32 %shl to i64
+  %xor = xor i64 %conv1, %a
+  ret i64 %xor
+}
+
+define i32 @sbext_i32(i32 %a, i32 %b) nounwind {
+; RV32I-LABEL: sbext_i32:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    srl a0, a0, a1
+; RV32I-NEXT:    andi a0, a0, 1
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbext_i32:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    sbext a0, a0, a1
+; RV32IB-NEXT:    ret
+  %and = and i32 %b, 31
+  %shr = lshr i32 %a, %and
+  %and1 = and i32 %shr, 1
+  ret i32 %and1
+}
+
+define i64 @sbext_i64(i64 %a, i64 %b) nounwind {
+; RV32I-LABEL: sbext_i64:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    andi a3, a2, 63
+; RV32I-NEXT:    addi a4, a3, -32
+; RV32I-NEXT:    bltz a4, .LBB6_2
+; RV32I-NEXT:  # %bb.1:
+; RV32I-NEXT:    srl a0, a1, a4
+; RV32I-NEXT:    j .LBB6_3
+; RV32I-NEXT:  .LBB6_2:
+; RV32I-NEXT:    srl a0, a0, a2
+; RV32I-NEXT:    addi a2, zero, 31
+; RV32I-NEXT:    sub a2, a2, a3
+; RV32I-NEXT:    slli a1, a1, 1
+; RV32I-NEXT:    sll a1, a1, a2
+; RV32I-NEXT:    or a0, a0, a1
+; RV32I-NEXT:  .LBB6_3:
+; RV32I-NEXT:    andi a0, a0, 1
+; RV32I-NEXT:    mv a1, zero
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbext_i64:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    andi a3, a2, 63
+; RV32IB-NEXT:    addi a4, a3, -32
+; RV32IB-NEXT:    bltz a4, .LBB6_2
+; RV32IB-NEXT:  # %bb.1:
+; RV32IB-NEXT:    srl a0, a1, a4
+; RV32IB-NEXT:    j .LBB6_3
+; RV32IB-NEXT:  .LBB6_2:
+; RV32IB-NEXT:    srl a0, a0, a2
+; RV32IB-NEXT:    addi a2, zero, 31
+; RV32IB-NEXT:    sub a2, a2, a3
+; RV32IB-NEXT:    slli a1, a1, 1
+; RV32IB-NEXT:    sll a1, a1, a2
+; RV32IB-NEXT:    or a0, a0, a1
+; RV32IB-NEXT:  .LBB6_3:
+; RV32IB-NEXT:    andi a0, a0, 1
+; RV32IB-NEXT:    mv a1, zero
+; RV32IB-NEXT:    ret
+  %conv = and i64 %b, 63
+  %shr = lshr i64 %a, %conv
+  %and1 = and i64 %shr, 1
+  ret i64 %and1
+}
+
+define i32 @sbexti_i32(i32 %a) nounwind {
+; RV32I-LABEL: sbexti_i32:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    srli a0, a0, 5
+; RV32I-NEXT:    andi a0, a0, 1
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbexti_i32:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    sbexti a0, a0, 5
+; RV32IB-NEXT:    ret
+  %shr = lshr i32 %a, 5
+  %and = and i32 %shr, 1
+  ret i32 %and
+}
+
+define i64 @sbexti_i64(i64 %a) nounwind {
+; RV32I-LABEL: sbexti_i64:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    srli a0, a0, 5
+; RV32I-NEXT:    andi a0, a0, 1
+; RV32I-NEXT:    mv a1, zero
+; RV32I-NEXT:    ret
+;
+; RV32IB-LABEL: sbexti_i64:
+; RV32IB:       # %bb.0:
+; RV32IB-NEXT:    sbexti a0, a0, 5
+; RV32IB-NEXT:    mv a1, zero
+; RV32IB-NEXT:    ret
+  %shr = lshr i64 %a, 5
+  %and = and i64 %shr, 1
+  ret i64 %and
+}
Index: llvm/test/CodeGen/RISCV/rv64Zbs.ll
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/RISCV/rv64Zbs.ll
@@ -0,0 +1,185 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=riscv64 -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=RV64I
+; RUN: llc -mtriple=riscv64 -mattr=+experimental-b -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=RV64IB
+; RUN: llc -mtriple=riscv64 -mattr=+experimental-zbs -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=RV64IB
+
+define signext i32 @sbclr_i32(i32 signext %a, i32 signext %b) nounwind {
+; RV64I-LABEL: sbclr_i32:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    addi a2, zero, 1
+; RV64I-NEXT:    sllw a1, a2, a1
+; RV64I-NEXT:    not a1, a1
+; RV64I-NEXT:    and a0, a1, a0
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbclr_i32:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbclrw a0, a0, a1
+; RV64IB-NEXT:    ret
+  %and = and i32 %b, 31
+  %shl = shl nuw i32 1, %and
+  %neg = xor i32 %shl, -1
+  %and1 = and i32 %neg, %a
+  ret i32 %and1
+}
+
+define i64 @sbclr_i64(i64 %a, i64 %b) nounwind {
+; RV64I-LABEL: sbclr_i64:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    addi a2, zero, 1
+; RV64I-NEXT:    sll a1, a2, a1
+; RV64I-NEXT:    not a1, a1
+; RV64I-NEXT:    and a0, a1, a0
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbclr_i64:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbclr a0, a0, a1
+; RV64IB-NEXT:    ret
+  %and = and i64 %b, 63
+  %shl = shl nuw i64 1, %and
+  %neg = xor i64 %shl, -1
+  %and1 = and i64 %neg, %a
+  ret i64 %and1
+}
+
+define signext i32 @sbset_i32(i32 signext %a, i32 signext %b) nounwind {
+; RV64I-LABEL: sbset_i32:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    addi a2, zero, 1
+; RV64I-NEXT:    sllw a1, a2, a1
+; RV64I-NEXT:    or a0, a1, a0
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbset_i32:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbsetw a0, a0, a1
+; RV64IB-NEXT:    ret
+  %and = and i32 %b, 31
+  %shl = shl nuw i32 1, %and
+  %or = or i32 %shl, %a
+  ret i32 %or
+}
+
+define i64 @sbset_i64(i64 %a, i64 %b) nounwind {
+; RV64I-LABEL: sbset_i64:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    addi a2, zero, 1
+; RV64I-NEXT:    sll a1, a2, a1
+; RV64I-NEXT:    or a0, a1, a0
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbset_i64:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbset a0, a0, a1
+; RV64IB-NEXT:    ret
+  %conv = and i64 %b, 63
+  %shl = shl nuw i64 1, %conv
+  %or = or i64 %shl, %a
+  ret i64 %or
+}
+
+define signext i32 @sbinv_i32(i32 signext %a, i32 signext %b) nounwind {
+; RV64I-LABEL: sbinv_i32:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    addi a2, zero, 1
+; RV64I-NEXT:    sllw a1, a2, a1
+; RV64I-NEXT:    xor a0, a1, a0
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbinv_i32:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbinvw a0, a0, a1
+; RV64IB-NEXT:    ret
+  %and = and i32 %b, 31
+  %shl = shl nuw i32 1, %and
+  %xor = xor i32 %shl, %a
+  ret i32 %xor
+}
+
+define i64 @sbinv_i64(i64 %a, i64 %b) nounwind {
+; RV64I-LABEL: sbinv_i64:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    addi a2, zero, 1
+; RV64I-NEXT:    sll a1, a2, a1
+; RV64I-NEXT:    xor a0, a1, a0
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbinv_i64:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbinv a0, a0, a1
+; RV64IB-NEXT:    ret
+  %conv = and i64 %b, 63
+  %shl = shl nuw i64 1, %conv
+  %xor = xor i64 %shl, %a
+  ret i64 %xor
+}
+
+define signext i32 @sbext_i32(i32 signext %a, i32 signext %b) nounwind {
+; RV64I-LABEL: sbext_i32:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    srlw a0, a0, a1
+; RV64I-NEXT:    andi a0, a0, 1
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbext_i32:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbextw a0, a0, a1
+; RV64IB-NEXT:    ret
+  %and = and i32 %b, 31
+  %shr = lshr i32 %a, %and
+  %and1 = and i32 %shr, 1
+  ret i32 %and1
+}
+
+define i64 @sbext_i64(i64 %a, i64 %b) nounwind {
+; RV64I-LABEL: sbext_i64:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    srl a0, a0, a1
+; RV64I-NEXT:    andi a0, a0, 1
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbext_i64:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbext a0, a0, a1
+; RV64IB-NEXT:    ret
+  %conv = and i64 %b, 63
+  %shr = lshr i64 %a, %conv
+  %and1 = and i64 %shr, 1
+  ret i64 %and1
+}
+
+define signext i32 @sbexti_i32(i32 signext %a) nounwind {
+; RV64I-LABEL: sbexti_i32:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    srli a0, a0, 5
+; RV64I-NEXT:    andi a0, a0, 1
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbexti_i32:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbexti a0, a0, 5
+; RV64IB-NEXT:    ret
+  %shr = lshr i32 %a, 5
+  %and = and i32 %shr, 1
+  ret i32 %and
+}
+
+define i64 @sbexti_i64(i64 %a) nounwind {
+; RV64I-LABEL: sbexti_i64:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    srli a0, a0, 5
+; RV64I-NEXT:    andi a0, a0, 1
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: sbexti_i64:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    sbexti a0, a0, 5
+; RV64IB-NEXT:    ret
+  %shr = lshr i64 %a, 5
+  %and = and i64 %shr, 1
+  ret i64 %and
+}