[heap] Remove max executable size configuration.

src/ppc/assembler-ppc.cc

Index: src/ppc/assembler-ppc.cc
diff --git a/src/ppc/assembler-ppc.cc b/src/ppc/assembler-ppc.cc
index ec6330a351d225f143506d9ffa96f755c0e76ad1..d3c57a479b75c89f1fca675c24ecf1602b4f3264 100644
--- a/src/ppc/assembler-ppc.cc
+++ b/src/ppc/assembler-ppc.cc
@@ -1984,7 +1984,14 @@ void Assembler::GrowBuffer(int needed) {
   if (space < needed) {
     desc.buffer_size += needed - space;
   }
-  CHECK_GT(desc.buffer_size, 0);  // no overflow
+
+  // Some internal data structures overflow for very large buffers,
+  // they must ensure that kMaximalBufferSize is not too large.
+  if (desc.buffer_size > kMaximalBufferSize ||
+      static_cast<size_t>(desc.buffer_size) >
+          isolate_data().max_old_generation_size_) {
+    V8::FatalProcessOutOfMemory("Assembler::GrowBuffer");
+  }
 
   // Set up new buffer.
   desc.buffer = NewArray<byte>(desc.buffer_size);