Revert "Tweak inlining heuristics."

This reverts commit fcb7613d3aaa9a6802800b6e957aaad51cedf6dc.

Change-Id: Idc0df6a2f68e8b5aa740bb1259f19c2953811510
diff --git a/compiler/optimizing/inliner.cc b/compiler/optimizing/inliner.cc
index 6d5f6eb..db11709 100644
--- a/compiler/optimizing/inliner.cc
+++ b/compiler/optimizing/inliner.cc
@@ -42,14 +42,7 @@
 
 namespace art {
 
-static constexpr size_t kMaximumNumberOfHInstructions = 32;
-
-// Limit the number of dex registers that we accumulate while inlining
-// to avoid creating large amount of nested environments.
-static constexpr size_t kMaximumNumberOfCumulatedDexRegisters = 64;
-
-// Avoid inlining within a huge method due to memory pressure.
-static constexpr size_t kMaximumCodeUnitSize = 4096;
+static constexpr size_t kMaximumNumberOfHInstructions = 12;
 
 void HInliner::Run() {
   const CompilerOptions& compiler_options = compiler_driver_->GetCompilerOptions();
@@ -57,9 +50,6 @@
       || (compiler_options.GetInlineMaxCodeUnits() == 0)) {
     return;
   }
-  if (caller_compilation_unit_.GetCodeItem()->insns_size_in_code_units_ > kMaximumCodeUnitSize) {
-    return;
-  }
   if (graph_->IsDebuggable()) {
     // For simplicity, we currently never inline when the graph is debuggable. This avoids
     // doing some logic in the runtime to discover if a method could have been inlined.
@@ -587,7 +577,6 @@
                      compiler_driver_,
                      handles_,
                      stats_,
-                     total_number_of_dex_registers_ + code_item->registers_size_,
                      depth_ + 1);
     inliner.Run();
     number_of_instructions_budget += inliner.number_of_inlined_instructions_;
@@ -619,10 +608,6 @@
   HReversePostOrderIterator it(*callee_graph);
   it.Advance();  // Past the entry block, it does not contain instructions that prevent inlining.
   size_t number_of_instructions = 0;
-
-  bool can_inline_environment =
-      total_number_of_dex_registers_ < kMaximumNumberOfCumulatedDexRegisters;
-
   for (; !it.Done(); it.Advance()) {
     HBasicBlock* block = it.Current();
     if (block->IsLoopHeader()) {
@@ -636,17 +621,10 @@
          instr_it.Advance()) {
       if (number_of_instructions++ ==  number_of_instructions_budget) {
         VLOG(compiler) << "Method " << PrettyMethod(method_index, callee_dex_file)
-                       << " is not inlined because its caller has reached"
-                       << " its instruction budget limit.";
+                       << " could not be inlined because it is too big.";
         return false;
       }
       HInstruction* current = instr_it.Current();
-      if (!can_inline_environment && current->NeedsEnvironment()) {
-        VLOG(compiler) << "Method " << PrettyMethod(method_index, callee_dex_file)
-                       << " is not inlined because its caller has reached"
-                       << " its environment budget limit.";
-        return false;
-      }
 
       if (current->IsInvokeInterface()) {
         // Disable inlining of interface calls. The cost in case of entering the