diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 1b8bd9dc2..7486f676e 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -3487,7 +3487,7 @@ skip_dynamic_range_lvalue_expansion:;
 				goto apply_newNode;
 			}
 
-			if (str == "\\$size" || str == "\\$bits" || str == "\\$high" || str == "\\$low" || str == "\\$left" || str == "\\$right")
+			if (str == "\\$increment" || str == "\\$size" || str == "\\$bits" || str == "\\$high" || str == "\\$low" || str == "\\$left" || str == "\\$right")
 			{
 				int dim = 1;
 				if (str == "\\$bits") {
@@ -3556,6 +3556,8 @@ skip_dynamic_range_lvalue_expansion:;
 					result = left;
 				else if (str == "\\$right")
 					result = right;
+				else if (str == "\\$increment")
+					result = left >= right ? 1 : -1;
 				else if (str == "\\$size")
 					result = width;
 				else { // str == "\\$bits"
diff --git a/tests/sat/sizebits.sv b/tests/sat/sizebits.sv
index de2e7ecc1..a31cae78c 100644
--- a/tests/sat/sizebits.sv
+++ b/tests/sat/sizebits.sv
@@ -90,4 +90,17 @@ assert property ($right(z, 3) == 0);
 assert property ($right(z[3]) == 9);
 assert property ($right(z[3][3]) == 0);
 assert property ($right(z[3], 2) == 0);
+
+assert property ($increment(x) == 1);
+assert property ($increment(y) == -1);
+assert property ($increment(y, 1) == -1);
+assert property ($increment(y, (1+1)) == 1);
+
+assert property ($increment(z) == 1);
+assert property ($increment(z, 1) == 1);
+assert property ($increment(z, 2) == -1);
+assert property ($increment(z, 3) == 1);
+assert property ($increment(z[3]) == -1);
+assert property ($increment(z[3][3]) == 1);
+assert property ($increment(z[3], 2) == 1);
 endmodule
diff --git a/tests/svtypes/struct_sizebits.sv b/tests/svtypes/struct_sizebits.sv
index 092d9ecef..7f33fe72c 100644
--- a/tests/svtypes/struct_sizebits.sv
+++ b/tests/svtypes/struct_sizebits.sv
@@ -107,6 +107,19 @@ always_comb begin
 	assert ($right(s.sz.z[3]) == 9);
 	assert ($right(s.sz.z[3][3]) == 4);
 	assert ($right(s.sz.z[3], 2) == 4);
+
+	assert ($increment(s.x) == 1);
+	assert ($increment(s.sy.y) == -1);
+	assert ($increment(s.sy.y, 1) == -1);
+	assert ($increment(s.sy.y, (1+1)) == 1);
+
+	assert ($increment(s.sz.z) == 1);
+	assert ($increment(s.sz.z, 1) == 1);
+	assert ($increment(s.sz.z, 2) == -1);
+	assert ($increment(s.sz.z, 3) == -1);
+	assert ($increment(s.sz.z[3]) == -1);
+	assert ($increment(s.sz.z[3][3]) == -1);
+	assert ($increment(s.sz.z[3], 2) == -1);
 end
 
 endmodule