[aarch64-port-dev ] [12] RFR(S): 8207247 AARCH64: Enable Minimal and Client VM builds

[Andrew Dinn]

On 29/08/18 16:34, Andrew Haley wrote:
> On 08/29/2018 03:19 PM, Aleksei Voitylov wrote:
>> here is an updated webrev: 
>> http://cr.openjdk.java.net/~avoitylov/webrev.8207247.02
>>
>> I'm not sure it looks cleaner since in_scratch_emit_size is a C2-only 
>> concept, though. This was the reason I changed it.
> 
> Yeah, I get that, but I want to keep the code history as clean as
> possible.
One minimal change which would clarify the code would be to rename
in_scratch_emit_size to a name that does not drag in the C2-specific
details:

   // We need a trampoline if branches are far.
   if (far_branches()) {
+    bool avoid_emit = false;
+#ifdef COMPILER2
     // We don't want to emit a trampoline if C2 is generating dummy
     // code during its branch shortening phase.
     CompileTask* task = ciEnv::current()->task();
-    bool in_scratch_emit_size =
+    avoid_emit =
       (task != NULL && is_c2_compile(task->comp_level()) &&
        Compile::current()->in_scratch_emit_size());
+#endif
     if (!avoid_emit) {
       address stub = emit_trampoline_stub(offset(), entry.target());
       if (stub == NULL) {
         return NULL; // CodeCache is full
       }

Even better would be to use do_emit and reverse the logic but that
requires a slightly larger (but not much more complex) change:

   // We need a trampoline if branches are far.
   if (far_branches()) {
+    bool so_emit = true;
+#ifdef COMPILER2
     // We don't want to emit a trampoline if C2 is generating dummy
     // code during its branch shortening phase.
     CompileTask* task = ciEnv::current()->task();
-    bool in_scratch_emit_size =
-      (task != NULL && is_c2_compile(task->comp_level()) &&
-       Compile::current()->in_scratch_emit_size());
+    do_emit =
+      !(task != NULL && is_c2_compile(task->comp_level()) &&
+        Compile::current()->in_scratch_emit_size());
+#endif
     if (do_emit) {
       address stub = emit_trampoline_stub(offset(), entry.target());
       if (stub == NULL) {
         return NULL; // CodeCache is full
       }

regards,


Andrew Dinn
-----------
Senior Principal Software Engineer
Red Hat UK Ltd
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