diff --git a/grep.c b/grep.c
index 7bb0360869..5bec7fd793 100644
--- a/grep.c
+++ b/grep.c
@@ -595,6 +595,35 @@ static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 	}
 }
 
+static struct grep_expr *grep_not_expr(struct grep_expr *expr)
+{
+	struct grep_expr *z = xcalloc(1, sizeof(*z));
+	z->node = GREP_NODE_NOT;
+	z->u.unary = expr;
+	return z;
+}
+
+static struct grep_expr *grep_binexp(enum grep_expr_node kind,
+				     struct grep_expr *left,
+				     struct grep_expr *right)
+{
+	struct grep_expr *z = xcalloc(1, sizeof(*z));
+	z->node = kind;
+	z->u.binary.left = left;
+	z->u.binary.right = right;
+	return z;
+}
+
+static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right)
+{
+	return grep_binexp(GREP_NODE_OR, left, right);
+}
+
+static struct grep_expr *grep_and_expr(struct grep_expr *left, struct grep_expr *right)
+{
+	return grep_binexp(GREP_NODE_AND, left, right);
+}
+
 static struct grep_expr *compile_pattern_or(struct grep_pat **);
 static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
 {
@@ -638,12 +667,10 @@ static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 		if (!p->next)
 			die("--not not followed by pattern expression");
 		*list = p->next;
-		CALLOC_ARRAY(x, 1);
-		x->node = GREP_NODE_NOT;
-		x->u.unary = compile_pattern_not(list);
-		if (!x->u.unary)
+		x = compile_pattern_not(list);
+		if (!x)
 			die("--not followed by non pattern expression");
-		return x;
+		return grep_not_expr(x);
 	default:
 		return compile_pattern_atom(list);
 	}
@@ -652,7 +679,7 @@ static struct grep_expr *compile_pattern_not(struct grep_pat **list)
 static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 {
 	struct grep_pat *p;
-	struct grep_expr *x, *y, *z;
+	struct grep_expr *x, *y;
 
 	x = compile_pattern_not(list);
 	p = *list;
@@ -665,11 +692,7 @@ static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 		y = compile_pattern_and(list);
 		if (!y)
 			die("--and not followed by pattern expression");
-		CALLOC_ARRAY(z, 1);
-		z->node = GREP_NODE_AND;
-		z->u.binary.left = x;
-		z->u.binary.right = y;
-		return z;
+		return grep_and_expr(x, y);
 	}
 	return x;
 }
@@ -677,7 +700,7 @@ static struct grep_expr *compile_pattern_and(struct grep_pat **list)
 static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 {
 	struct grep_pat *p;
-	struct grep_expr *x, *y, *z;
+	struct grep_expr *x, *y;
 
 	x = compile_pattern_and(list);
 	p = *list;
@@ -685,11 +708,7 @@ static struct grep_expr *compile_pattern_or(struct grep_pat **list)
 		y = compile_pattern_or(list);
 		if (!y)
 			die("not a pattern expression %s", p->pattern);
-		CALLOC_ARRAY(z, 1);
-		z->node = GREP_NODE_OR;
-		z->u.binary.left = x;
-		z->u.binary.right = y;
-		return z;
+		return grep_or_expr(x, y);
 	}
 	return x;
 }
@@ -699,14 +718,6 @@ static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
 	return compile_pattern_or(list);
 }
 
-static struct grep_expr *grep_not_expr(struct grep_expr *expr)
-{
-	struct grep_expr *z = xcalloc(1, sizeof(*z));
-	z->node = GREP_NODE_NOT;
-	z->u.unary = expr;
-	return z;
-}
-
 static struct grep_expr *grep_true_expr(void)
 {
 	struct grep_expr *z = xcalloc(1, sizeof(*z));
@@ -714,15 +725,6 @@ static struct grep_expr *grep_true_expr(void)
 	return z;
 }
 
-static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right)
-{
-	struct grep_expr *z = xcalloc(1, sizeof(*z));
-	z->node = GREP_NODE_OR;
-	z->u.binary.left = left;
-	z->u.binary.right = right;
-	return z;
-}
-
 static struct grep_expr *prep_header_patterns(struct grep_opt *opt)
 {
 	struct grep_pat *p;