diff --git a/gcc/testsuite/gcc.dg/pr98766.c b/gcc/testsuite/gcc.dg/pr98766.c
new file mode 100644
index 00000000000..d388fd2aa87
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr98766.c
@@ -0,0 +1,12 @@
+/* PR tree-optimization/98766.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O3 --param=avoid-fma-max-bits=8 " } */
+/* { dg-additional-options "-march=armv8.2-a+sve" { target aarch64*-*-* } } */
+
+extern int a[];
+void c(short *d) {
+  for (int e = 0; e < 9; e++)
+    a[e] = d[e] * 2;
+}
+
diff --git a/gcc/tree-ssa-math-opts.c b/gcc/tree-ssa-math-opts.c
index d6201d3cb94..c4a6492b50d 100644
--- a/gcc/tree-ssa-math-opts.c
+++ b/gcc/tree-ssa-math-opts.c
@@ -3252,8 +3252,8 @@ convert_mult_to_fma (gimple *mul_stmt, tree op1, tree op2,
 
   bool check_defer
     = (state->m_deferring_p
-       && (tree_to_shwi (TYPE_SIZE (type))
-	   <= param_avoid_fma_max_bits));
+       && maybe_le (tree_to_poly_int64 (TYPE_SIZE (type)),
+		    param_avoid_fma_max_bits));
   bool defer = check_defer;
   bool seen_negate_p = false;
   /* Make sure that the multiplication statement becomes dead after