From fb2bca07ddc497b6d38f92cd9e5e712a0f2ffef7 Mon Sep 17 00:00:00 2001
From: Nathan Henderson <nathan.t.henderson@outlook.com>
Date: Thu, 31 Oct 2024 13:38:46 -0400
Subject: [PATCH] Add configure support to enable RAM class persistence

Related: https://github.ibm.com/runtimes/openj9/issues/755
Related: https://github.com/eclipse-openj9/openj9/pull/20387
Signed-off-by: Nathan Henderson <nathan.henderson@ibm.com>
---
 closed/OpenJ9.gmk                  | 13 +++++++++++++
 closed/autoconf/custom-hook.m4     | 20 ++++++++++++++++++++
 closed/autoconf/custom-spec.gmk.in |  1 +
 3 files changed, 34 insertions(+)

diff --git a/closed/OpenJ9.gmk b/closed/OpenJ9.gmk
index 22a5b982e0..4687395ede 100644
--- a/closed/OpenJ9.gmk
+++ b/closed/OpenJ9.gmk
@@ -305,6 +305,13 @@ else # OPENJ9_ENABLE_OPENJDK_METHODHANDLES
   FEATURE_SED_SCRIPT += $(call SedDisable,opt_openjdkMethodhandle)
 endif # OPENJ9_ENABLE_OPENJDK_METHODHANDLES
 
+# Adjust snapshots enablement flags.
+ifeq (true,$(OPENJ9_ENABLE_SNAPSHOTS))
+  FEATURE_SED_SCRIPT += $(call SedEnable,opt_snapshots)
+else # OPENJ9_ENABLE_SNAPSHOTS
+  FEATURE_SED_SCRIPT += $(call SedDisable,opt_snapshots)
+endif # OPENJ9_ENABLE_SNAPSHOTS
+
 # Disable windows rebase.
 SPEC_SED_SCRIPT += $(call SedDisable,uma_windowsRebase)
 
@@ -477,6 +484,12 @@ ifeq (true,$(OPENJ9_ENABLE_CMAKE))
     CMAKE_ARGS += -DJ9VM_OPT_OPENJDK_METHODHANDLE=OFF
   endif # OPENJ9_ENABLE_OPENJDK_METHODHANDLES
 
+  ifeq (true,$(OPENJ9_ENABLE_SNAPSHOTS))
+    CMAKE_ARGS += -DJ9VM_OPT_SNAPSHOTS=ON
+  else # OPENJ9_ENABLE_SNAPSHOTS
+    CMAKE_ARGS += -DJ9VM_OPT_SNAPSHOTS=OFF
+  endif # OPENJ9_ENABLE_SNAPSHOTS
+
   # Propagate configure option '--disable-warnings-as-errors-omr' to OMR.
   ifeq (false,$(WARNINGS_AS_ERRORS_OMR))
     CMAKE_ARGS += -DOMR_WARNINGS_AS_ERRORS=OFF
diff --git a/closed/autoconf/custom-hook.m4 b/closed/autoconf/custom-hook.m4
index deb337a38b..d01cb1d6e2 100644
--- a/closed/autoconf/custom-hook.m4
+++ b/closed/autoconf/custom-hook.m4
@@ -49,6 +49,7 @@ AC_DEFUN_ONCE([CUSTOM_EARLY_HOOK],
   OPENJ9_CONFIGURE_JITSERVER
   OPENJ9_CONFIGURE_NUMA
   OPENJ9_CONFIGURE_OPENJDK_METHODHANDLES
+  OPENJ9_CONFIGURE_SNAPSHOTS
   OPENJ9_CONFIGURE_WARNINGS
   OPENJ9_THIRD_PARTY_REQUIREMENTS
   OPENJ9_CHECK_NASM_VERSION
@@ -521,6 +522,25 @@ AC_DEFUN([OPENJ9_CONFIGURE_OPENJDK_METHODHANDLES],
   AC_SUBST(OPENJ9_ENABLE_OPENJDK_METHODHANDLES)
 ])
 
+AC_DEFUN([OPENJ9_CONFIGURE_SNAPSHOTS],
+[
+  AC_MSG_CHECKING([for snapshot support])
+  AC_ARG_ENABLE([snapshots], [AS_HELP_STRING([--enable-snapshots],
+      [enable RAM persistence snapshots @<:@disabled@:>@])])
+  OPENJ9_ENABLE_SNAPSHOTS=false
+  if test "x$enable_snapshots" = xyes ; then
+    AC_MSG_RESULT([yes (explicitly enabled)])
+    OPENJ9_ENABLE_SNAPSHOTS=true
+  elif test "x$enable_snapshots" = xno ; then
+    AC_MSG_RESULT([no (explicitly disabled)])
+  elif test "x$enable_snapshots" = x ; then
+    AC_MSG_RESULT([no (default)])
+  else
+    AC_MSG_ERROR([--enable-snapshots accepts no argument])
+  fi
+  AC_SUBST(OPENJ9_ENABLE_SNAPSHOTS)
+])
+
 AC_DEFUN([OPENJ9_PLATFORM_SETUP],
 [
   AC_ARG_WITH(noncompressedrefs, [AS_HELP_STRING([--with-noncompressedrefs],
diff --git a/closed/autoconf/custom-spec.gmk.in b/closed/autoconf/custom-spec.gmk.in
index 2ea6623745..fd4bd3bb47 100644
--- a/closed/autoconf/custom-spec.gmk.in
+++ b/closed/autoconf/custom-spec.gmk.in
@@ -62,6 +62,7 @@ OPENJ9_ENABLE_DEMOS                 := @OPENJ9_ENABLE_DEMOS@
 OPENJ9_ENABLE_JFR                   := @OPENJ9_ENABLE_JFR@
 OPENJ9_ENABLE_JITSERVER             := @OPENJ9_ENABLE_JITSERVER@
 OPENJ9_ENABLE_OPENJDK_METHODHANDLES := @OPENJ9_ENABLE_OPENJDK_METHODHANDLES@
+OPENJ9_ENABLE_SNAPSHOTS             := @OPENJ9_ENABLE_SNAPSHOTS@
 
 # for constructing version output
 COMPILER_VERSION_STRING := @COMPILER_VERSION_STRING@