diff --git a/src/cmd/compile/internal/ssa/gen/386.rules b/src/cmd/compile/internal/ssa/gen/386.rules
index e8d19cf3c9..3a54a2a206 100644
--- a/src/cmd/compile/internal/ssa/gen/386.rules
+++ b/src/cmd/compile/internal/ssa/gen/386.rules
@@ -1151,10 +1151,14 @@
   -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p (SHLLconst <i.Type> [1] i) mem)
 
 // Combine stores into larger (unaligned) stores.
-(MOVBstore [i] {s} p (SHRLconst [8] w) x:(MOVBstore [i-1] {s} p w mem))
+(MOVBstore [i] {s} p (SHR(W|L)const [8] w) x:(MOVBstore [i-1] {s} p w mem))
   && x.Uses == 1
   && clobber(x)
   -> (MOVWstore [i-1] {s} p w mem)
+(MOVBstore [i] {s} p w x:(MOVBstore {s} [i+1] p (SHR(W|L)const [8] w) mem))
+  && x.Uses == 1
+  && clobber(x)
+  -> (MOVWstore [i] {s} p w mem)
 (MOVBstore [i] {s} p (SHRLconst [j] w) x:(MOVBstore [i-1] {s} p w0:(SHRLconst [j-8] w) mem))
   && x.Uses == 1
   && clobber(x)
@@ -1168,10 +1172,14 @@
   && clobber(x)
   -> (MOVLstore [i-2] {s} p w0 mem)
 
-(MOVBstoreidx1 [i] {s} p idx (SHRLconst [8] w) x:(MOVBstoreidx1 [i-1] {s} p idx w mem))
+(MOVBstoreidx1 [i] {s} p idx (SHR(L|W)const [8] w) x:(MOVBstoreidx1 [i-1] {s} p idx w mem))
   && x.Uses == 1
   && clobber(x)
   -> (MOVWstoreidx1 [i-1] {s} p idx w mem)
+(MOVBstoreidx1 [i] {s} p idx w x:(MOVBstoreidx1 [i+1] {s} p idx (SHR(L|W)const [8] w) mem))
+  && x.Uses == 1
+  && clobber(x)
+  -> (MOVWstoreidx1 [i] {s} p idx w mem)
 (MOVBstoreidx1 [i] {s} p idx (SHRLconst [j] w) x:(MOVBstoreidx1 [i-1] {s} p idx w0:(SHRLconst [j-8] w) mem))
   && x.Uses == 1
   && clobber(x)
diff --git a/src/cmd/compile/internal/ssa/rewrite386.go b/src/cmd/compile/internal/ssa/rewrite386.go
index 14784bef3a..2fce9c151e 100644
--- a/src/cmd/compile/internal/ssa/rewrite386.go
+++ b/src/cmd/compile/internal/ssa/rewrite386.go
@@ -106,13 +106,13 @@ func rewriteValue386(v *Value) bool {
 	case Op386MOVBloadidx1:
 		return rewriteValue386_Op386MOVBloadidx1_0(v)
 	case Op386MOVBstore:
-		return rewriteValue386_Op386MOVBstore_0(v)
+		return rewriteValue386_Op386MOVBstore_0(v) || rewriteValue386_Op386MOVBstore_10(v)
 	case Op386MOVBstoreconst:
 		return rewriteValue386_Op386MOVBstoreconst_0(v)
 	case Op386MOVBstoreconstidx1:
 		return rewriteValue386_Op386MOVBstoreconstidx1_0(v)
 	case Op386MOVBstoreidx1:
-		return rewriteValue386_Op386MOVBstoreidx1_0(v) || rewriteValue386_Op386MOVBstoreidx1_10(v)
+		return rewriteValue386_Op386MOVBstoreidx1_0(v) || rewriteValue386_Op386MOVBstoreidx1_10(v) || rewriteValue386_Op386MOVBstoreidx1_20(v)
 	case Op386MOVLload:
 		return rewriteValue386_Op386MOVLload_0(v)
 	case Op386MOVLloadidx1:
@@ -5545,6 +5545,51 @@ func rewriteValue386_Op386MOVBstore_0(v *Value) bool {
 		v.AddArg(mem)
 		return true
 	}
+	// match: (MOVBstore [i] {s} p (SHRWconst [8] w) x:(MOVBstore [i-1] {s} p w mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstore [i-1] {s} p w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[2]
+		p := v.Args[0]
+		v_1 := v.Args[1]
+		if v_1.Op != Op386SHRWconst {
+			break
+		}
+		if v_1.AuxInt != 8 {
+			break
+		}
+		w := v_1.Args[0]
+		x := v.Args[2]
+		if x.Op != Op386MOVBstore {
+			break
+		}
+		if x.AuxInt != i-1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[2]
+		if p != x.Args[0] {
+			break
+		}
+		if w != x.Args[1] {
+			break
+		}
+		mem := x.Args[2]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstore)
+		v.AuxInt = i - 1
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
 	// match: (MOVBstore [i] {s} p (SHRLconst [8] w) x:(MOVBstore [i-1] {s} p w mem))
 	// cond: x.Uses == 1 && clobber(x)
 	// result: (MOVWstore [i-1] {s} p w mem)
@@ -5590,6 +5635,99 @@ func rewriteValue386_Op386MOVBstore_0(v *Value) bool {
 		v.AddArg(mem)
 		return true
 	}
+	// match: (MOVBstore [i] {s} p w x:(MOVBstore {s} [i+1] p (SHRWconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstore [i] {s} p w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[2]
+		p := v.Args[0]
+		w := v.Args[1]
+		x := v.Args[2]
+		if x.Op != Op386MOVBstore {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[2]
+		if p != x.Args[0] {
+			break
+		}
+		x_1 := x.Args[1]
+		if x_1.Op != Op386SHRWconst {
+			break
+		}
+		if x_1.AuxInt != 8 {
+			break
+		}
+		if w != x_1.Args[0] {
+			break
+		}
+		mem := x.Args[2]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstore)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	return false
+}
+func rewriteValue386_Op386MOVBstore_10(v *Value) bool {
+	// match: (MOVBstore [i] {s} p w x:(MOVBstore {s} [i+1] p (SHRLconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstore [i] {s} p w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[2]
+		p := v.Args[0]
+		w := v.Args[1]
+		x := v.Args[2]
+		if x.Op != Op386MOVBstore {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[2]
+		if p != x.Args[0] {
+			break
+		}
+		x_1 := x.Args[1]
+		if x_1.Op != Op386SHRLconst {
+			break
+		}
+		if x_1.AuxInt != 8 {
+			break
+		}
+		if w != x_1.Args[0] {
+			break
+		}
+		mem := x.Args[2]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstore)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
 	// match: (MOVBstore [i] {s} p (SHRLconst [j] w) x:(MOVBstore [i-1] {s} p w0:(SHRLconst [j-8] w) mem))
 	// cond: x.Uses == 1 && clobber(x)
 	// result: (MOVWstore [i-1] {s} p w0 mem)
@@ -6166,6 +6304,612 @@ func rewriteValue386_Op386MOVBstoreidx1_0(v *Value) bool {
 		v.AddArg(mem)
 		return true
 	}
+	// match: (MOVBstoreidx1 [i] {s} p idx (SHRWconst [8] w) x:(MOVBstoreidx1 [i-1] {s} p idx w mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i-1] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		p := v.Args[0]
+		idx := v.Args[1]
+		v_2 := v.Args[2]
+		if v_2.Op != Op386SHRWconst {
+			break
+		}
+		if v_2.AuxInt != 8 {
+			break
+		}
+		w := v_2.Args[0]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i-1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if p != x.Args[0] {
+			break
+		}
+		if idx != x.Args[1] {
+			break
+		}
+		if w != x.Args[2] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i - 1
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} p idx (SHRWconst [8] w) x:(MOVBstoreidx1 [i-1] {s} idx p w mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i-1] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		p := v.Args[0]
+		idx := v.Args[1]
+		v_2 := v.Args[2]
+		if v_2.Op != Op386SHRWconst {
+			break
+		}
+		if v_2.AuxInt != 8 {
+			break
+		}
+		w := v_2.Args[0]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i-1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if idx != x.Args[0] {
+			break
+		}
+		if p != x.Args[1] {
+			break
+		}
+		if w != x.Args[2] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i - 1
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	return false
+}
+func rewriteValue386_Op386MOVBstoreidx1_10(v *Value) bool {
+	// match: (MOVBstoreidx1 [i] {s} idx p (SHRWconst [8] w) x:(MOVBstoreidx1 [i-1] {s} p idx w mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i-1] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		idx := v.Args[0]
+		p := v.Args[1]
+		v_2 := v.Args[2]
+		if v_2.Op != Op386SHRWconst {
+			break
+		}
+		if v_2.AuxInt != 8 {
+			break
+		}
+		w := v_2.Args[0]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i-1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if p != x.Args[0] {
+			break
+		}
+		if idx != x.Args[1] {
+			break
+		}
+		if w != x.Args[2] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i - 1
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} idx p (SHRWconst [8] w) x:(MOVBstoreidx1 [i-1] {s} idx p w mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i-1] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		idx := v.Args[0]
+		p := v.Args[1]
+		v_2 := v.Args[2]
+		if v_2.Op != Op386SHRWconst {
+			break
+		}
+		if v_2.AuxInt != 8 {
+			break
+		}
+		w := v_2.Args[0]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i-1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if idx != x.Args[0] {
+			break
+		}
+		if p != x.Args[1] {
+			break
+		}
+		if w != x.Args[2] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i - 1
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} p idx w x:(MOVBstoreidx1 [i+1] {s} p idx (SHRLconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		p := v.Args[0]
+		idx := v.Args[1]
+		w := v.Args[2]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if p != x.Args[0] {
+			break
+		}
+		if idx != x.Args[1] {
+			break
+		}
+		x_2 := x.Args[2]
+		if x_2.Op != Op386SHRLconst {
+			break
+		}
+		if x_2.AuxInt != 8 {
+			break
+		}
+		if w != x_2.Args[0] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} p idx w x:(MOVBstoreidx1 [i+1] {s} idx p (SHRLconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		p := v.Args[0]
+		idx := v.Args[1]
+		w := v.Args[2]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if idx != x.Args[0] {
+			break
+		}
+		if p != x.Args[1] {
+			break
+		}
+		x_2 := x.Args[2]
+		if x_2.Op != Op386SHRLconst {
+			break
+		}
+		if x_2.AuxInt != 8 {
+			break
+		}
+		if w != x_2.Args[0] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} idx p w x:(MOVBstoreidx1 [i+1] {s} p idx (SHRLconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		idx := v.Args[0]
+		p := v.Args[1]
+		w := v.Args[2]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if p != x.Args[0] {
+			break
+		}
+		if idx != x.Args[1] {
+			break
+		}
+		x_2 := x.Args[2]
+		if x_2.Op != Op386SHRLconst {
+			break
+		}
+		if x_2.AuxInt != 8 {
+			break
+		}
+		if w != x_2.Args[0] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} idx p w x:(MOVBstoreidx1 [i+1] {s} idx p (SHRLconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		idx := v.Args[0]
+		p := v.Args[1]
+		w := v.Args[2]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if idx != x.Args[0] {
+			break
+		}
+		if p != x.Args[1] {
+			break
+		}
+		x_2 := x.Args[2]
+		if x_2.Op != Op386SHRLconst {
+			break
+		}
+		if x_2.AuxInt != 8 {
+			break
+		}
+		if w != x_2.Args[0] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} p idx w x:(MOVBstoreidx1 [i+1] {s} p idx (SHRWconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		p := v.Args[0]
+		idx := v.Args[1]
+		w := v.Args[2]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if p != x.Args[0] {
+			break
+		}
+		if idx != x.Args[1] {
+			break
+		}
+		x_2 := x.Args[2]
+		if x_2.Op != Op386SHRWconst {
+			break
+		}
+		if x_2.AuxInt != 8 {
+			break
+		}
+		if w != x_2.Args[0] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} p idx w x:(MOVBstoreidx1 [i+1] {s} idx p (SHRWconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		p := v.Args[0]
+		idx := v.Args[1]
+		w := v.Args[2]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if idx != x.Args[0] {
+			break
+		}
+		if p != x.Args[1] {
+			break
+		}
+		x_2 := x.Args[2]
+		if x_2.Op != Op386SHRWconst {
+			break
+		}
+		if x_2.AuxInt != 8 {
+			break
+		}
+		if w != x_2.Args[0] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} idx p w x:(MOVBstoreidx1 [i+1] {s} p idx (SHRWconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		idx := v.Args[0]
+		p := v.Args[1]
+		w := v.Args[2]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if p != x.Args[0] {
+			break
+		}
+		if idx != x.Args[1] {
+			break
+		}
+		x_2 := x.Args[2]
+		if x_2.Op != Op386SHRWconst {
+			break
+		}
+		if x_2.AuxInt != 8 {
+			break
+		}
+		if w != x_2.Args[0] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	// match: (MOVBstoreidx1 [i] {s} idx p w x:(MOVBstoreidx1 [i+1] {s} idx p (SHRWconst [8] w) mem))
+	// cond: x.Uses == 1 && clobber(x)
+	// result: (MOVWstoreidx1 [i] {s} p idx w mem)
+	for {
+		i := v.AuxInt
+		s := v.Aux
+		_ = v.Args[3]
+		idx := v.Args[0]
+		p := v.Args[1]
+		w := v.Args[2]
+		x := v.Args[3]
+		if x.Op != Op386MOVBstoreidx1 {
+			break
+		}
+		if x.AuxInt != i+1 {
+			break
+		}
+		if x.Aux != s {
+			break
+		}
+		_ = x.Args[3]
+		if idx != x.Args[0] {
+			break
+		}
+		if p != x.Args[1] {
+			break
+		}
+		x_2 := x.Args[2]
+		if x_2.Op != Op386SHRWconst {
+			break
+		}
+		if x_2.AuxInt != 8 {
+			break
+		}
+		if w != x_2.Args[0] {
+			break
+		}
+		mem := x.Args[3]
+		if !(x.Uses == 1 && clobber(x)) {
+			break
+		}
+		v.reset(Op386MOVWstoreidx1)
+		v.AuxInt = i
+		v.Aux = s
+		v.AddArg(p)
+		v.AddArg(idx)
+		v.AddArg(w)
+		v.AddArg(mem)
+		return true
+	}
+	return false
+}
+func rewriteValue386_Op386MOVBstoreidx1_20(v *Value) bool {
 	// match: (MOVBstoreidx1 [i] {s} p idx (SHRLconst [j] w) x:(MOVBstoreidx1 [i-1] {s} p idx w0:(SHRLconst [j-8] w) mem))
 	// cond: x.Uses == 1 && clobber(x)
 	// result: (MOVWstoreidx1 [i-1] {s} p idx w0 mem)
@@ -6276,9 +7020,6 @@ func rewriteValue386_Op386MOVBstoreidx1_0(v *Value) bool {
 		v.AddArg(mem)
 		return true
 	}
-	return false
-}
-func rewriteValue386_Op386MOVBstoreidx1_10(v *Value) bool {
 	// match: (MOVBstoreidx1 [i] {s} idx p (SHRLconst [j] w) x:(MOVBstoreidx1 [i-1] {s} p idx w0:(SHRLconst [j-8] w) mem))
 	// cond: x.Uses == 1 && clobber(x)
 	// result: (MOVWstoreidx1 [i-1] {s} p idx w0 mem)
diff --git a/test/codegen/memcombine.go b/test/codegen/memcombine.go
index 230aadfb74..d0043da7ef 100644
--- a/test/codegen/memcombine.go
+++ b/test/codegen/memcombine.go
@@ -113,11 +113,13 @@ func load_be16_idx(b []byte, idx int) {
 
 func load_le_byte2_uint16(s []byte) uint16 {
 	// arm64:`MOVHU\t\(R[0-9]+\)`,-`ORR`,-`MOVB`
+	// 386:`MOVWLZX\s\([A-Z]+\)`,-`MOVB`,-`ORL`
 	return uint16(s[0]) | uint16(s[1])<<8
 }
 
 func load_le_byte2_uint16_inv(s []byte) uint16 {
 	// arm64:`MOVHU\t\(R[0-9]+\)`,-`ORR`,-`MOVB`
+	// 386:`MOVWLZX\s\([A-Z]+\)`,-`MOVB`,-`ORL`
 	return uint16(s[1])<<8 | uint16(s[0])
 }
 
@@ -173,11 +175,13 @@ func load_be_byte8_uint64_inv(s []byte) uint64 {
 
 func load_le_byte2_uint16_idx(s []byte, idx int) uint16 {
 	// arm64:`MOVHU\s\(R[0-9]+\)\(R[0-9]+\)`,-`ORR`,-`MOVB`
+	// 386:`MOVWLZX\s\([A-Z]+\)\([A-Z]+`,-`ORL`,-`MOVB`
 	return uint16(s[idx]) | uint16(s[idx+1])<<8
 }
 
 func load_le_byte2_uint16_idx_inv(s []byte, idx int) uint16 {
 	// arm64:`MOVHU\s\(R[0-9]+\)\(R[0-9]+\)`,-`ORR`,-`MOVB`
+	// 386:`MOVWLZX\s\([A-Z]+\)\([A-Z]+`,-`ORL`,-`MOVB`
 	return uint16(s[idx+1])<<8 | uint16(s[idx])
 }
 
@@ -405,9 +409,16 @@ func store_be16_idx(b []byte, idx int) {
 func store_le_byte_2(b []byte, val uint16) {
 	_ = b[2]
 	// arm64:`MOVH\sR[0-9]+,\s1\(R[0-9]+\)`,-`MOVB`
+	// 386:`MOVW\s[A-Z]+,\s1\([A-Z]+\)`,-`MOVB`
 	b[1], b[2] = byte(val), byte(val>>8)
 }
 
+func store_le_byte_2_inv(b []byte, val uint16) {
+	_ = b[2]
+	// 386:`MOVW\s[A-Z]+,\s1\([A-Z]+\)`,-`MOVB`
+	b[2], b[1] = byte(val>>8), byte(val)
+}
+
 func store_le_byte_4(b []byte, val uint32) {
 	_ = b[4]
 	// arm64:`MOVW\sR[0-9]+,\s1\(R[0-9]+\)`,-`MOVB`,-`MOVH`
@@ -441,9 +452,16 @@ func store_be_byte_8(b []byte, val uint64) {
 func store_le_byte_2_idx(b []byte, idx int, val uint16) {
 	_, _ = b[idx+0], b[idx+1]
 	// arm64:`MOVH\sR[0-9]+,\s\(R[0-9]+\)\(R[0-9]+\)`,-`MOVB`
+	// 386:`MOVW\s[A-Z]+,\s\([A-Z]+\)\([A-Z]+`,-`MOVB`
 	b[idx+1], b[idx+0] = byte(val>>8), byte(val)
 }
 
+func store_le_byte_2_idx_inv(b []byte, idx int, val uint16) {
+	_, _ = b[idx+0], b[idx+1]
+	// 386:`MOVW\s[A-Z]+,\s\([A-Z]+\)\([A-Z]+`,-`MOVB`
+	b[idx+0], b[idx+1] = byte(val), byte(val>>8)
+}
+
 func store_le_byte_4_idx(b []byte, idx int, val uint32) {
 	_, _, _, _ = b[idx+0], b[idx+1], b[idx+2], b[idx+3]
 	// arm64:`MOVW\sR[0-9]+,\s\(R[0-9]+\)\(R[0-9]+\)`,-`MOVB`,-`MOVH`