From abc76c6b5b3e2eabd3fd3ceb96ffe02979dc8956 Mon Sep 17 00:00:00 2001
From: Martin Doerr <mdoerr@openjdk.org>
Date: Wed, 11 Jun 2025 08:28:31 +0000
Subject: [PATCH] 8359126: [AIX] new test TestImplicitNullChecks.java fails

Reviewed-by: rcastanedalo, dbriemann
---
 .../jtreg/compiler/gcbarriers/TestImplicitNullChecks.java    | 5 ++++-
 .../compiler/lib/ir_framework/test/IREncodingPrinter.java    | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/test/hotspot/jtreg/compiler/gcbarriers/TestImplicitNullChecks.java b/test/hotspot/jtreg/compiler/gcbarriers/TestImplicitNullChecks.java
index a77a51312de..34583b8fea9 100644
--- a/test/hotspot/jtreg/compiler/gcbarriers/TestImplicitNullChecks.java
+++ b/test/hotspot/jtreg/compiler/gcbarriers/TestImplicitNullChecks.java
@@ -67,7 +67,10 @@ public class TestImplicitNullChecks {
     }
 
     @Test
-    @IR(applyIfOr = {"UseZGC", "true", "UseG1GC", "true"},
+    // On AIX, implicit null checks are limited because the zero page is
+    // readable (but not writable). See os::zero_page_read_protected().
+    @IR(applyIfPlatform = {"aix", "false"},
+        applyIfOr = {"UseZGC", "true", "UseG1GC", "true"},
         counts = {IRNode.NULL_CHECK, "1"},
         phase = CompilePhase.FINAL_CODE)
     static Object testLoad(Outer o) {
diff --git a/test/hotspot/jtreg/compiler/lib/ir_framework/test/IREncodingPrinter.java b/test/hotspot/jtreg/compiler/lib/ir_framework/test/IREncodingPrinter.java
index 4ad95ab786f..eef9998ebf8 100644
--- a/test/hotspot/jtreg/compiler/lib/ir_framework/test/IREncodingPrinter.java
+++ b/test/hotspot/jtreg/compiler/lib/ir_framework/test/IREncodingPrinter.java
@@ -62,6 +62,7 @@ public class IREncodingPrinter {
     // as adding non-existent platforms can lead to skipped tests.
     private static final List<String> irTestingPlatforms = new ArrayList<String>(Arrays.asList(
         // os.family
+        "aix",
         "linux",
         "mac",
         "windows",
@@ -346,7 +347,9 @@ public class IREncodingPrinter {
         }
 
         String os = "";
-        if (Platform.isLinux()) {
+        if (Platform.isAix()) {
+            os = "aix";
+        } else if (Platform.isLinux()) {
             os = "linux";
         } else if (Platform.isOSX()) {
             os = "mac";