diff --git a/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp b/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
index 8402a41252bd3..1dd12ab396fd8 100644
--- a/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
+++ b/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
@@ -1045,7 +1045,8 @@ static bool isSupportedInstr(const MachineInstr &MI) {
   case RISCV::VSLIDEUP_VI:
   case RISCV::VSLIDEDOWN_VX:
   case RISCV::VSLIDEDOWN_VI:
-  // TODO: Handle v[f]slide1up, but not v[f]slide1down.
+  case RISCV::VSLIDE1UP_VX:
+  case RISCV::VFSLIDE1UP_VF:
   // Vector Single-Width Floating-Point Add/Subtract Instructions
   case RISCV::VFADD_VF:
   case RISCV::VFADD_VV:
diff --git a/llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll b/llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll
index f84eebe1c6d6a..e6407b322c447 100644
--- a/llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll
+++ b/llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll
@@ -3514,6 +3514,92 @@ define <vscale x 4 x i32> @vslidedown_vi(<vscale x 4 x i32> %a, iXLen %vl) {
   ret <vscale x 4 x i32> %2
 }
 
+define <vscale x 4 x i32> @vslide1up_vx(<vscale x 4 x i32> %a, iXLen %b, iXLen %vl) {
+; NOVLOPT-LABEL: vslide1up_vx:
+; NOVLOPT:       # %bb.0:
+; NOVLOPT-NEXT:    vsetvli a2, zero, e32, m2, ta, ma
+; NOVLOPT-NEXT:    vslide1up.vx v10, v8, a0
+; NOVLOPT-NEXT:    vsetvli zero, a1, e32, m2, ta, ma
+; NOVLOPT-NEXT:    vadd.vv v8, v10, v10
+; NOVLOPT-NEXT:    ret
+;
+; VLOPT-LABEL: vslide1up_vx:
+; VLOPT:       # %bb.0:
+; VLOPT-NEXT:    vsetvli zero, a1, e32, m2, ta, ma
+; VLOPT-NEXT:    vslide1up.vx v10, v8, a0
+; VLOPT-NEXT:    vadd.vv v8, v10, v10
+; VLOPT-NEXT:    ret
+  %1 = call <vscale x 4 x i32> @llvm.riscv.vslide1up(<vscale x 4 x i32> poison, <vscale x 4 x i32> %a, iXLen %b, iXLen -1)
+  %2 = call <vscale x 4 x i32> @llvm.riscv.vadd(<vscale x 4 x i32> poison, <vscale x 4 x i32> %1, <vscale x 4 x i32> %1, iXLen %vl)
+  ret <vscale x 4 x i32> %2
+}
+
+define <vscale x 4 x float> @vfslide1up_vf(<vscale x 4 x float> %a, float %b, iXLen %vl) {
+; NOVLOPT-LABEL: vfslide1up_vf:
+; NOVLOPT:       # %bb.0:
+; NOVLOPT-NEXT:    vsetvli a1, zero, e32, m2, ta, ma
+; NOVLOPT-NEXT:    vfslide1up.vf v10, v8, fa0
+; NOVLOPT-NEXT:    vsetvli zero, a0, e32, m2, ta, ma
+; NOVLOPT-NEXT:    vfadd.vv v8, v10, v10
+; NOVLOPT-NEXT:    ret
+;
+; VLOPT-LABEL: vfslide1up_vf:
+; VLOPT:       # %bb.0:
+; VLOPT-NEXT:    vsetvli zero, a0, e32, m2, ta, ma
+; VLOPT-NEXT:    vfslide1up.vf v10, v8, fa0
+; VLOPT-NEXT:    vfadd.vv v8, v10, v10
+; VLOPT-NEXT:    ret
+  %1 = call <vscale x 4 x float> @llvm.riscv.vfslide1up(<vscale x 4 x float> poison, <vscale x 4 x float> %a, float %b, iXLen -1)
+  %2 = call <vscale x 4 x float> @llvm.riscv.vfadd(<vscale x 4 x float> poison, <vscale x 4 x float> %1, <vscale x 4 x float> %1, iXLen 7, iXLen %vl)
+  ret <vscale x 4 x float> %2
+}
+
+; Negative test – not safe to reduce vl
+
+define <vscale x 4 x i32> @vslide1down_vx(<vscale x 4 x i32> %a, iXLen %b, iXLen %vl) {
+; NOVLOPT-LABEL: vslide1down_vx:
+; NOVLOPT:       # %bb.0:
+; NOVLOPT-NEXT:    vsetvli a2, zero, e32, m2, ta, ma
+; NOVLOPT-NEXT:    vslide1down.vx v8, v8, a0
+; NOVLOPT-NEXT:    vsetvli zero, a1, e32, m2, ta, ma
+; NOVLOPT-NEXT:    vadd.vv v8, v8, v8
+; NOVLOPT-NEXT:    ret
+;
+; VLOPT-LABEL: vslide1down_vx:
+; VLOPT:       # %bb.0:
+; VLOPT-NEXT:    vsetvli a2, zero, e32, m2, ta, ma
+; VLOPT-NEXT:    vslide1down.vx v8, v8, a0
+; VLOPT-NEXT:    vsetvli zero, a1, e32, m2, ta, ma
+; VLOPT-NEXT:    vadd.vv v8, v8, v8
+; VLOPT-NEXT:    ret
+  %1 = call <vscale x 4 x i32> @llvm.riscv.vslide1down(<vscale x 4 x i32> poison, <vscale x 4 x i32> %a, iXLen %b, iXLen -1)
+  %2 = call <vscale x 4 x i32> @llvm.riscv.vadd(<vscale x 4 x i32> poison, <vscale x 4 x i32> %1, <vscale x 4 x i32> %1, iXLen %vl)
+  ret <vscale x 4 x i32> %2
+}
+
+; Negative test – not safe to reduce vl
+
+define <vscale x 4 x float> @vfslide1down_vf(<vscale x 4 x float> %a, float %b, iXLen %vl) {
+; NOVLOPT-LABEL: vfslide1down_vf:
+; NOVLOPT:       # %bb.0:
+; NOVLOPT-NEXT:    vsetvli a1, zero, e32, m2, ta, ma
+; NOVLOPT-NEXT:    vfslide1down.vf v8, v8, fa0
+; NOVLOPT-NEXT:    vsetvli zero, a0, e32, m2, ta, ma
+; NOVLOPT-NEXT:    vfadd.vv v8, v8, v8
+; NOVLOPT-NEXT:    ret
+;
+; VLOPT-LABEL: vfslide1down_vf:
+; VLOPT:       # %bb.0:
+; VLOPT-NEXT:    vsetvli a1, zero, e32, m2, ta, ma
+; VLOPT-NEXT:    vfslide1down.vf v8, v8, fa0
+; VLOPT-NEXT:    vsetvli zero, a0, e32, m2, ta, ma
+; VLOPT-NEXT:    vfadd.vv v8, v8, v8
+; VLOPT-NEXT:    ret
+  %1 = call <vscale x 4 x float> @llvm.riscv.vfslide1down(<vscale x 4 x float> poison, <vscale x 4 x float> %a, float %b, iXLen -1)
+  %2 = call <vscale x 4 x float> @llvm.riscv.vfadd(<vscale x 4 x float> poison, <vscale x 4 x float> %1, <vscale x 4 x float> %1, iXLen 7, iXLen %vl)
+  ret <vscale x 4 x float> %2
+}
+
 define <vscale x 4 x float> @vfadd_vv(<vscale x 4 x float> %a, <vscale x 4 x float> %b, iXLen %vl) {
 ; NOVLOPT-LABEL: vfadd_vv:
 ; NOVLOPT:       # %bb.0: