diff --git a/src/V3DfgPeephole.cpp b/src/V3DfgPeephole.cpp
index c48bdbbe7..089655971 100644
--- a/src/V3DfgPeephole.cpp
+++ b/src/V3DfgPeephole.cpp
@@ -1274,6 +1274,33 @@ class V3DfgPeephole final : public DfgVisitor {
         }
     }
 
+    void visit(DfgMux* const vtxp) override {
+        DfgVertex* const fromp = vtxp->fromp();
+        DfgVertex* const lsbp = vtxp->lsbp();
+        FileLine* const flp = vtxp->fileline();
+
+        if (DfgConst* const lsbConstp = lsbp->cast<DfgConst>()) {
+            APPLYING(REPLACE_MUX_WITH_SEL) {
+                replace(make<DfgSel>(vtxp, fromp, lsbConstp->num().toUInt()));
+                return;
+            }
+        }
+
+        if (isZero(fromp)) {
+            APPLYING(FOLD_MUX_FROM_ZERO) {
+                replace(makeZero(flp, vtxp->width()));
+                return;
+            }
+        }
+
+        if (isOnes(fromp)) {
+            APPLYING(FOLD_MUX_FROM_ONES) {
+                replace(makeOnes(flp, vtxp->width()));
+                return;
+            }
+        }
+    }
+
     //=========================================================================
     //  DfgVertexBinary - bitwise
     //=========================================================================
diff --git a/src/V3DfgPeepholePatterns.h b/src/V3DfgPeepholePatterns.h
index 5910167bd..b8aa011c9 100644
--- a/src/V3DfgPeepholePatterns.h
+++ b/src/V3DfgPeepholePatterns.h
@@ -31,6 +31,8 @@
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_ASSOC_BINARY_LHS_OF_RHS) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_ASSOC_BINARY_RHS_OF_LHS) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_BINARY) \
+    _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_MUX_FROM_ONES) \
+    _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_MUX_FROM_ZERO) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_SEL) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_SELF_EQ) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, FOLD_SELF_GT) \
@@ -117,6 +119,7 @@
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_EXTEND) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_LOGAND_WITH_AND) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_LOGOR_WITH_OR) \
+    _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_MUX_WITH_SEL) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_NESTED_CONCAT_OF_ADJOINING_SELS_ON_LHS) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_NESTED_CONCAT_OF_ADJOINING_SELS_ON_RHS) \
     _FOR_EACH_DFG_PEEPHOLE_OPTIMIZATION_APPLY(macro, REPLACE_NOT_EQ) \
diff --git a/test_regress/t/t_dfg_peephole.v b/test_regress/t/t_dfg_peephole.v
index c580708d7..15b6100d1 100644
--- a/test_regress/t/t_dfg_peephole.v
+++ b/test_regress/t/t_dfg_peephole.v
@@ -33,6 +33,8 @@ module t (
   wire        logic [127:0] rand_aa = {2{rand_a}};
   wire        logic [63:0] const_a;
   wire        logic [63:0] const_b;
+  wire        logic [63:0] zero;
+  wire        logic [63:0] ones;
   wire        logic signed [63:0] sconst_a;
   wire        logic signed [63:0] sconst_b;
              logic [63:0] array [3:0];
@@ -305,6 +307,9 @@ module t (
   `signal(FOLD_SELF_LTS, srand_a < srand_a);
   `signal(FOLD_SELF_LE, rand_a <= rand_a);
   `signal(FOLD_SELF_LES, srand_a <= srand_a);
+  `signal(FOLD_MUX_FROM_ONES, ones[rand_a[5:0]]);
+  `signal(FOLD_MUX_FROM_ZERO, zero[rand_a[5:0]]);
+  `signal(REPLACE_MUX_WITH_SEL, rand_a[const_a[5:0]]);
 
   // Operators that should work wiht mismatched widths
   `signal(MISMATCHED_ShiftL,const_a << 4'd2);
@@ -366,4 +371,6 @@ module t (
   assign const_b  = 64'h98badefc10325647;
   assign sconst_a = 64'hfedcba9876543210;
   assign sconst_b = 64'hba0123456789cdef;
+  assign zero = '0;
+  assign ones = '1;
 endmodule