RFR (XS) 8242073: x86_32 build failure after JDK-8241040

[Aleksey Shipilev]

Build bug:
  https://bugs.openjdk.java.net/browse/JDK-8242073

immU8 is undefined in x86_32.ad, so new matchers in x86.ad fail. Copying immU8 definition from
x86_64.ad helps. Matched the operand block order and internal format of x86_32.ad with this patch:

diff -r f50a7df94744 src/hotspot/cpu/x86/x86_32.ad
--- a/src/hotspot/cpu/x86/x86_32.ad     Fri Apr 03 07:27:53 2020 +0100
+++ b/src/hotspot/cpu/x86/x86_32.ad     Fri Apr 03 09:29:33 2020 +0200
@@ -3367,10 +3367,19 @@
   op_cost(5);
   format %{ %}
   interface(CONST_INTER);
 %}

+operand immU8() %{
+  predicate((0 <= n->get_int()) && (n->get_int() <= 255));
+  match(ConI);
+
+  op_cost(5);
+  format %{ %}
+  interface(CONST_INTER);
+%}
+
 operand immI16() %{
   predicate((-32768 <= n->get_int()) && (n->get_int() <= 32767));
   match(ConI);

   op_cost(10);

Testing: x86_32 build

-- 
Thanks,
-Aleksey