PPC: temp fix for constant pool sharing issue

Sharing WasmCall/StubCall will lead to relocation
being processed more than once in NativeModule::AddCode
for wasm.

R=joransiu@ca.ibm.com

Change-Id: I88d9a1a956fe36ef81e0a4c61d7dedf868bdf9a3
Reviewed-on: https://chromium-review.googlesource.com/c/1344510
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#57700}

src/ppc/assembler-ppc.h

@@ -1441,10 +1441,13 @@ class Assembler : public AssemblerBase {
   void RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data = 0);
   ConstantPoolEntry::Access ConstantPoolAddEntry(RelocInfo::Mode rmode,
                                                  intptr_t value) {
-    bool sharing_ok = RelocInfo::IsNone(rmode) ||
-                      (!options().record_reloc_info_for_serialization &&
-                       RelocInfo::IsShareableRelocMode(rmode) &&
-                       !is_constant_pool_entry_sharing_blocked());
+    bool sharing_ok =
+        RelocInfo::IsNone(rmode) ||
+        (!options().record_reloc_info_for_serialization &&
+         RelocInfo::IsShareableRelocMode(rmode) &&
+         !is_constant_pool_entry_sharing_blocked() &&
+         // TODO(johnyan): make the following rmode shareable
+         !RelocInfo::IsWasmCall(rmode) && !RelocInfo::IsWasmStubCall(rmode));
     return constant_pool_builder_.AddEntry(pc_offset(), value, sharing_ok);
   }
   ConstantPoolEntry::Access ConstantPoolAddEntry(Double value) {