Index: llvm/lib/Target/RISCV/MCTargetDesc/RISCVMatInt.cpp
===================================================================
--- llvm/lib/Target/RISCV/MCTargetDesc/RISCVMatInt.cpp
+++ llvm/lib/Target/RISCV/MCTargetDesc/RISCVMatInt.cpp
@@ -182,6 +182,34 @@
     }
   }
 
+  // Try to use BCLRI for upper 32-bit if the lower 32-bit is negative int32,
+  // or use BSETI for upper 32-bit if the lower 32-bit is positive int32.
+  if (Res.size() > 2 && ActiveFeatures[RISCV::FeatureStdExtZbs]) {
+    assert(ActiveFeatures[RISCV::Feature64Bit] &&
+           "Expected RV32 to only need 2 instructions");
+    int32_t Lo = Val;
+    uint32_t Hi = Val >> 32;
+    unsigned Opc = 0;
+    RISCVMatInt::InstSeq TmpSeq;
+    generateInstSeqImpl(Lo, ActiveFeatures, TmpSeq);
+    // Check if it is profitable to use BCLRI/BSETI.
+    if (Lo > 0 && TmpSeq.size() + countPopulation(Hi) < Res.size()) {
+      Opc = RISCV::BSETI;
+    } else if (Lo < 0 && TmpSeq.size() + countPopulation(~Hi) < Res.size()) {
+      Opc = RISCV::BCLRI;
+      Hi = ~Hi;
+    }
+    // Search for each bit and build corresponding BCLRI/BSETI.
+    if (Opc > 0) {
+      while (Hi != 0) {
+        unsigned Bit = countTrailingZeros(Hi);
+        TmpSeq.push_back(RISCVMatInt::Inst(Opc, Bit + 32));
+        Hi &= ~(1 << Bit);
+      }
+      Res = TmpSeq;
+    }
+  }
+
   return Res;
 }
 
Index: llvm/test/CodeGen/RISCV/imm.ll
===================================================================
--- llvm/test/CodeGen/RISCV/imm.ll
+++ llvm/test/CodeGen/RISCV/imm.ll
@@ -841,13 +841,12 @@
 ;
 ; RV64IZBS-LABEL: imm_2reg_1:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    addi a0, zero, -1
-; RV64IZBS-NEXT:    slli a0, a0, 35
-; RV64IZBS-NEXT:    addi a0, a0, 9
-; RV64IZBS-NEXT:    slli a0, a0, 13
-; RV64IZBS-NEXT:    addi a0, a0, 837
-; RV64IZBS-NEXT:    slli a0, a0, 12
-; RV64IZBS-NEXT:    addi a0, a0, 1656
+; RV64IZBS-NEXT:    lui a0, 74565
+; RV64IZBS-NEXT:    addiw a0, a0, 1656
+; RV64IZBS-NEXT:    bseti a0, a0, 60
+; RV64IZBS-NEXT:    bseti a0, a0, 61
+; RV64IZBS-NEXT:    bseti a0, a0, 62
+; RV64IZBS-NEXT:    bseti a0, a0, 63
 ; RV64IZBS-NEXT:    ret
   ret i64 -1152921504301427080 ; 0xF000_0000_1234_5678
 }
@@ -936,10 +935,9 @@
 ;
 ; RV64IZBS-LABEL: imm_5372288229:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 160
-; RV64IZBS-NEXT:    addiw a0, a0, 437
-; RV64IZBS-NEXT:    slli a0, a0, 13
-; RV64IZBS-NEXT:    addi a0, a0, -795
+; RV64IZBS-NEXT:    lui a0, 263018
+; RV64IZBS-NEXT:    addiw a0, a0, -795
+; RV64IZBS-NEXT:    bseti a0, a0, 32
 ; RV64IZBS-NEXT:    ret
   ret i64 5372288229
 }
@@ -970,10 +968,9 @@
 ;
 ; RV64IZBS-LABEL: imm_neg_5372288229:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 1048416
-; RV64IZBS-NEXT:    addiw a0, a0, -437
-; RV64IZBS-NEXT:    slli a0, a0, 13
-; RV64IZBS-NEXT:    addi a0, a0, 795
+; RV64IZBS-NEXT:    lui a0, 785558
+; RV64IZBS-NEXT:    addiw a0, a0, 795
+; RV64IZBS-NEXT:    bclri a0, a0, 32
 ; RV64IZBS-NEXT:    ret
   ret i64 -5372288229
 }
@@ -1004,10 +1001,9 @@
 ;
 ; RV64IZBS-LABEL: imm_8953813715:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 267
-; RV64IZBS-NEXT:    addiw a0, a0, -637
-; RV64IZBS-NEXT:    slli a0, a0, 13
-; RV64IZBS-NEXT:    addi a0, a0, -1325
+; RV64IZBS-NEXT:    lui a0, 88838
+; RV64IZBS-NEXT:    addiw a0, a0, -1325
+; RV64IZBS-NEXT:    bseti a0, a0, 33
 ; RV64IZBS-NEXT:    ret
   ret i64 8953813715
 }
@@ -1038,10 +1034,9 @@
 ;
 ; RV64IZBS-LABEL: imm_neg_8953813715:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 1048309
-; RV64IZBS-NEXT:    addiw a0, a0, 637
-; RV64IZBS-NEXT:    slli a0, a0, 13
-; RV64IZBS-NEXT:    addi a0, a0, 1325
+; RV64IZBS-NEXT:    lui a0, 959738
+; RV64IZBS-NEXT:    addiw a0, a0, 1325
+; RV64IZBS-NEXT:    bclri a0, a0, 33
 ; RV64IZBS-NEXT:    ret
   ret i64 -8953813715
 }
@@ -1175,12 +1170,9 @@
 ;
 ; RV64IZBS-LABEL: imm_70370820078523:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 256
-; RV64IZBS-NEXT:    addiw a0, a0, 31
-; RV64IZBS-NEXT:    slli a0, a0, 12
-; RV64IZBS-NEXT:    addi a0, a0, -273
-; RV64IZBS-NEXT:    slli a0, a0, 14
-; RV64IZBS-NEXT:    addi a0, a0, -1093
+; RV64IZBS-NEXT:    lui a0, 506812
+; RV64IZBS-NEXT:    addiw a0, a0, -1093
+; RV64IZBS-NEXT:    bseti a0, a0, 46
 ; RV64IZBS-NEXT:    ret
   ret i64 70370820078523 ; 0x40007bbbbbbb
 }
@@ -1217,13 +1209,9 @@
 ;
 ; RV64IZBS-LABEL: imm_neg_9223372034778874949:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    addi a0, zero, -1
-; RV64IZBS-NEXT:    slli a0, a0, 37
-; RV64IZBS-NEXT:    addi a0, a0, 31
-; RV64IZBS-NEXT:    slli a0, a0, 12
-; RV64IZBS-NEXT:    addi a0, a0, -273
-; RV64IZBS-NEXT:    slli a0, a0, 14
-; RV64IZBS-NEXT:    addi a0, a0, -1093
+; RV64IZBS-NEXT:    lui a0, 506812
+; RV64IZBS-NEXT:    addiw a0, a0, -1093
+; RV64IZBS-NEXT:    bseti a0, a0, 63
 ; RV64IZBS-NEXT:    ret
   ret i64 -9223372034778874949 ; 0x800000007bbbbbbb
 }
@@ -1260,13 +1248,10 @@
 ;
 ; RV64IZBS-LABEL: imm_neg_9223301666034697285:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 917505
-; RV64IZBS-NEXT:    slli a0, a0, 8
-; RV64IZBS-NEXT:    addi a0, a0, 31
-; RV64IZBS-NEXT:    slli a0, a0, 12
-; RV64IZBS-NEXT:    addi a0, a0, -273
-; RV64IZBS-NEXT:    slli a0, a0, 14
-; RV64IZBS-NEXT:    addi a0, a0, -1093
+; RV64IZBS-NEXT:    lui a0, 506812
+; RV64IZBS-NEXT:    addiw a0, a0, -1093
+; RV64IZBS-NEXT:    bseti a0, a0, 46
+; RV64IZBS-NEXT:    bseti a0, a0, 63
 ; RV64IZBS-NEXT:    ret
   ret i64 -9223301666034697285 ; 0x800040007bbbbbbb
 }
@@ -1329,10 +1314,9 @@
 ;
 ; RV64IZBS-LABEL: imm_neg_8798043653189:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 917475
-; RV64IZBS-NEXT:    addiw a0, a0, -273
-; RV64IZBS-NEXT:    slli a0, a0, 14
-; RV64IZBS-NEXT:    addi a0, a0, -1093
+; RV64IZBS-NEXT:    lui a0, 572348
+; RV64IZBS-NEXT:    addiw a0, a0, -1093
+; RV64IZBS-NEXT:    bclri a0, a0, 43
 ; RV64IZBS-NEXT:    ret
   ret i64 -8798043653189 ; 0xfffff7ff8bbbbbbb
 }
@@ -1366,11 +1350,9 @@
 ;
 ; RV64IZBS-LABEL: imm_9223372034904144827:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 1048343
-; RV64IZBS-NEXT:    addiw a0, a0, 1911
-; RV64IZBS-NEXT:    slli a0, a0, 12
-; RV64IZBS-NEXT:    addi a0, a0, 1911
-; RV64IZBS-NEXT:    srli a0, a0, 1
+; RV64IZBS-NEXT:    lui a0, 572348
+; RV64IZBS-NEXT:    addiw a0, a0, -1093
+; RV64IZBS-NEXT:    bclri a0, a0, 63
 ; RV64IZBS-NEXT:    ret
   ret i64 9223372034904144827 ; 0x7fffffff8bbbbbbb
 }
@@ -1408,13 +1390,10 @@
 ;
 ; RV64IZBS-LABEL: imm_neg_9223354442718100411:
 ; RV64IZBS:       # %bb.0:
-; RV64IZBS-NEXT:    lui a0, 524287
-; RV64IZBS-NEXT:    slli a0, a0, 6
-; RV64IZBS-NEXT:    addi a0, a0, -29
-; RV64IZBS-NEXT:    slli a0, a0, 12
-; RV64IZBS-NEXT:    addi a0, a0, -273
-; RV64IZBS-NEXT:    slli a0, a0, 14
-; RV64IZBS-NEXT:    addi a0, a0, -1093
+; RV64IZBS-NEXT:    lui a0, 572348
+; RV64IZBS-NEXT:    addiw a0, a0, -1093
+; RV64IZBS-NEXT:    bclri a0, a0, 44
+; RV64IZBS-NEXT:    bclri a0, a0, 63
 ; RV64IZBS-NEXT:    ret
   ret i64 9223354442718100411 ; 0x7fffefff8bbbbbbb
 }
Index: llvm/test/MC/RISCV/rv64zbs-aliases-valid.s
===================================================================
--- llvm/test/MC/RISCV/rv64zbs-aliases-valid.s
+++ llvm/test/MC/RISCV/rv64zbs-aliases-valid.s
@@ -30,3 +30,23 @@
 # CHECK-S-OBJ-NOALIAS: bexti t0, t1, 8
 # CHECK-S-OBJ: bexti t0, t1, 8
 bext x5, x6, 8
+
+# CHECK-S-OBJ-NOALIAS: lui t1, 572348
+# CHECK-S-OBJ-NOALIAS-NEXT: addiw t1, t1, -1093
+# CHECK-S-OBJ-NOALIAS-NEXT: bclri t1, t1, 44
+# CHECK-S-OBJ-NOALIAS-NEXT: bclri t1, t1, 63
+# CHECK-S-OBJ: lui t1, 572348
+# CHECK-S-OBJ-NEXT: addiw t1, t1, -1093
+# CHECK-S-OBJ-NEXT: bclri t1, t1, 44
+# CHECK-S-OBJ-NEXT: bclri t1, t1, 63
+li x6, 9223354442718100411
+
+# CHECK-S-OBJ-NOALIAS: lui t1, 506812
+# CHECK-S-OBJ-NOALIAS-NEXT: addiw t1, t1, -1093
+# CHECK-S-OBJ-NOALIAS-NEXT: bseti t1, t1, 46
+# CHECK-S-OBJ-NOALIAS-NEXT: bseti t1, t1, 63
+# CHECK-S-OBJ: lui t1, 506812
+# CHECK-S-OBJ-NEXT: addiw t1, t1, -1093
+# CHECK-S-OBJ-NEXT: bseti t1, t1, 46
+# CHECK-S-OBJ-NEXT: bseti t1, t1, 63
+li x6, -9223301666034697285