Extensionality Improvement in Main.gmk & Docs.gmk to generate docs

[Archana Nogriya]

If we have a conditional variable to set "
hotspot-$(JVM_VARIANT_MAIN)-gensrc" target then this can give way to 
alternate VMs like eclipse openj9 to extend that to set it appropriately.

diff --git a/make/Main.gmk b/make/Main.gmk
index 731e9c9934..444a835cb4 100644
--- a/make/Main.gmk
+++ b/make/Main.gmk
@@ -830,7 +830,8 @@ else
   docs-reference-api-modulegraph: exploded-image buildtools-modules
 
   # The gensrc steps for hotspot and jdk.jdi create html spec files.
-  docs-jdk-specs: jdk.jdi-gensrc \
+  JVM_DOCS_SPEC_TARGET ?= hotspot-$(JVM_VARIANT_MAIN)-gensrc
+  docs-jdk-specs: $(JVM_DOCS_SPEC_TARGET) jdk.jdi-gensrc \
       docs-jdk-index


######################################################################################

diff --git a/make/Docs.gmk b/make/Docs.gmk
index 644ffbf74a..73ffb8ebd2 100644
--- a/make/Docs.gmk
+++ b/make/Docs.gmk
@@ -561,12 +561,12 @@ $(eval $(call SetupCopyFiles, COPY_JDWP_PROTOCOL, \
 JDK_SPECS_TARGETS += $(COPY_JDWP_PROTOCOL)
 
#  Get jvmti.html from the main jvm variant (all variants' jvmti.html are 
identical).
-JVMTI_HTML := 
$(HOTSPOT_OUTPUTDIR)/variant-$(JVM_VARIANT_MAIN)/gensrc/jvmtifiles/jvmti.html
-$(eval $(call SetupCopyFiles, COPY_JVMTI_HTML, \
-    FILES := $(JVMTI_HTML), \
-    DEST := $(DOCS_OUTPUTDIR)/specs, \
-))
-JDK_SPECS_TARGETS += $(COPY_JVMTI_HTML)
+JVMTI_HTML ?= 
$(HOTSPOT_OUTPUTDIR)/variant-$(JVM_VARIANT_MAIN)/gensrc/jvmtifiles/jvmti.html
+$(eval $(call SetupCopyFiles, COPY_JVMTI_HTML, \
+    FILES := $(JVMTI_HTML), \
+    DEST := $(DOCS_OUTPUTDIR)/specs, \
+))
+JDK_SPECS_TARGETS += $(COPY_JVMTI_HTML)
 
Note: This proposal has been tested in local.

Thanks and Regards
Archana Nogriya 
IBM Java Runtime, Open Java Developer
IBM Hursley
Tel: Internal - 247073, External - +44 (0) 1962 81 7073
Office Mobile: 07500095480
Email: archana.nogriya at uk.ibm.com

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